Showing papers by "Medical University of South Carolina published in 1981"
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01 Jan 1981TL;DR: Dedications Contributors Preface Acknowledgements 1. Preinvasive Disease of the Cervix, William T. Creasman, 2. Role of Laparoscopic Surgery in Gynecologic Malignancies, Robert S. Zahn, and 3. Tumor Immunology, Host Defense Mechanisms, and Biologic Therapy, Philip J. DiSaia.
Abstract: Dedications Contributors Preface Acknowledgements 1. Preinvasive Disease of the Cervix, William T. Creasman 2. Preinvasive Disease of the Vagina and Vulva and Related Disorders, William T. Creasman 3. Invasive Cervical Cancer, Bradley J. Monk and Krishnansu S. Tewaria 4. Endometrial Hyperplasia, Estrogen Therapy, and the Prevention of Endometrial Cancer, Joan L. Walker and Rosemary E. Zuna 5. Adenocarcinoma of the Uterus, William T. Creasman 6. Sarcoma of the Uterus, D. Scott McMeekin 7. Gestational Trophoblastic Disease, John Soper and William T. Creasman 8. Invasive Cancer of the Vulva, Frederick B. Stehman 9. Invasive Cancer of the Vagina and Urethra, Brian M. Slomovitz and Robert L. Coleman 10. The Adnexal Mass and Early Ovarian Cancer, Philip J. DiSaia 11. Epithelial Ovarian Cancer, Larry J. Copeland 12. Germ Cell, Stromal, and Other Ovarian Tumors, Michael A. Bidus, Christopher M. Zahn and G. Scott Rose 13. Fallopian Tube Cancer, Jan S. Sunde, Keith J. Kaplan and G. Scott Rose 14. Breast Diseases, James V. Fiorica 15. Colorectal and Bladder Cancer, Philip J. DiSaia 16. Cancer in Pregnancy, Krishnansu S. Tewari 17. Complications of Disease and Therapy, Daniel L. Clarke-Pearson 18. Basic Principles of Chemotherapy, Christina S. Chu and Stephen C. Rubin 19. Tumor Immunology, Host Defense Mechanisms, and Biologic Therapy, Philip J. DiSaia 20. Genes and Cancer, David G. Mutch and Philip J. DiSaia 21. Palliative Care and Quality of Life, Bradley J. Monk and Lari Wenzel 22. Role of Laparoscopic Surgery in Gynecologic Malignancies, Robert S.Mannel 23. Epidemiology of Commonly Used Statistical Terms, and Analysis of Clinical Studies, Wendy R. Brewster APPENDICES A. Staging, William T. Creasman B. Modified from Common Terminology Criteria for Adverse Events (CTCAE), Philip J. DiSaia C. Blood Component Therapy, Philip J. DiSaia D. Suggested Recommendations for Routine Cancer Screening, William T. Creasman E. Nutritional Therapy, Philip J. DiSaia F. Basic Principles in Gynecologic Radiotherapy, Catheryn M. Yashar Index
700 citations
307 citations
TL;DR: In this article, the results of a longitudinal investigation of victim reactions to rape were reported, finding that victims were significantly more anxious, fearful, suspicious, and confused than non-victims for at least a year after their assaults.
Abstract: After reviewing previous work on psychological effects of a rape experience, this paper reports the results of a longitudinal investigation of victim reactions to rape. Adult victims (N = 20) were assessed at 1 month, 6 months, and 1 year postrape, and a group of matched non-victims (N = 20) were assessed at similar intervals. Findings were that victims were significantly more anxious, fearful, suspicious, and confused than nonvictims for at least a year after their assaults. However, there was significant improvement on those as well as other measures of personality and mood state over time, particularly between 1 and 6 months. Implications of these findings with regard to both social learning and feminist theory and therapy are discussed.
201 citations
TL;DR: The results suggest that warfarin may be useful in the treatment of SCCL and also support the hypothesis that the blood coagulation mechanism may be involved in the growth and spread of cancer in man.
Abstract: In a controlled, randomized study, survival of patients with small cell carcinoma of the lung (SCCL) was prolonged on addition of warfarin sodium to combination chemotherapy plus radiation therapy. Median survival for 25 control patients was 24 weeks and for 25 warfarin-treated patients was 50 weeks. This difference could not be accounted for by differences between groups in performance status, extent of disease, age, or sex. The survival advantage associated with warfarin administration was observed both for patients with extensive disease and for those who failed to achieve complete or partial remission. The warfarin-treated group also demonstrated a significantly increased time to first evidence of disease progression. These results suggest that warfarin may be useful in the treatment of SCCL and also support the hypothesis that the blood coagulation mechanism may be involved in the growth and spread of cancer in man. ( JAMA 1981;245:831-835)
197 citations
TL;DR: The increased levels of calcium in the lesion tissue confirm the previous morphologic finding of calcium deposits within axons in the lesions, and significantly elevated over control values within 45 min post-trauma.
186 citations
TL;DR: The Golgi Rapid and Kopsch techniques have been used to provide material for an examination of the internal neuronal organization of cortical area VII of the Macaca monkey and are hoped that this anatomical survey will provide a better foundation for physiological explorations of the region.
Abstract: The Golgi Rapid and Kopsch techniques have been used to provide material for an examination of the internal neuronal organization of cortical area VII of the Macaca monkey. The afferent and efferent relationships of area VII, as shown by axoplasmic transport tracing techniques in our own material and in previous studies in other laboratories, are reviewed. Comparison is made between the internal organisation of VI and VII cortex in terms of (1) the marked different in spiny and nonspiny neurons populations of granular layer 4, (2) the difference in relationship of lamina 6 pyramidal neurons to the overlying layers with a shift away from any relationship to granular layer 4 in VII, and (3) differences in the organization of VI lamina 4B and VII lamina 3B--both similarly placed, fiber-rich bands in the two cortical areas. The extrinsic relationships of VI and VII with the lateral geniculate nucleus, superior colliculus, pulvinar, peristriate cortex, cortical area STS, and with each other are compared in terms of laminar locations of efferent neurons and afferent axon terminal fields. It is hoped that this anatomical survey will provide a better foundation for physiological explorations of the region.
174 citations
TL;DR: In this article, the authors found that the incidence of secondary amenorrhea is higher in younger, nulliparous female runners and may be related to delayed onset of menarche.
161 citations
TL;DR: It is concluded that SHBG and the factor T/SHBG separate the hirsute population better than any of the androgens studied.
133 citations
TL;DR: The location of glycine next to the carboxyl terminal prolinamide of calcitonin is consistent with indications that glycine is required for the enzymatic amidation of proline to the prolinamines in cellular biosynthesis.
Abstract: Recombinant DNA techniques were used to analyze the structure of the messenger RNA encoding a precursor of calcitonin, a small calcium-regulating hormone of 32 amino acids. Analyses of the nucleotide sequences of cloned complementary DNA's comprising the entire coding sequence of the messenger RNA revealed that calcitonin is flanked at both its amino and carboxyl termini by peptide extensions linked to the hormone by short sequences of basic amino acids. The location of glycine next to the carboxyl terminal prolinamide of calcitonin is consistent with indications that glycine is required for the enzymatic amidation of proline to the prolinamide. During cellular biosynthesis, calcitonin arises from a large precursor protein by cleavages at both amino and carboxyl terminal residues of the hormone. These findings raise questions concerning the regulation of these cleavages and the potential biological functions of the precursor extensions derived from these cleavages.
126 citations
TL;DR: The most striking change was observed in low density lipoprotein cholesterol levels, which were more markedly increased in poor controlled females than in poorly controlled males, and in total, low density cholesterol levels were significantly increased in male patients in poor control.
Abstract: Plasma and lipoprotein cholesterol and triglycerides, glucose and haemoglobin A1c concentrations were measured in 106 patients (56 males) with insulin-dependent diabetes mellitus (age range 2–22 years) and 36 normal volunteers (19 males) with similar age and sex distribution. The diabetic patients were further divided into three subgroups: “good”, fair and poor control, based on 24 h glycosuria and haemoglobin A1c concentrations. Total, low density lipoprotein and very low density lipoprotein cholesterol levels were significantly increased in male patients in poor control when compared with the group in “good” control and with normal subjects. Triglyceride and very low density lipoprotein triglyceride levels were also significantly increased in poorly controlled males. The most significant difference however was a decrease of high density lipoprotein cholesterol in male patients in poor control. There was a significant inverse correlation between haemoglobin A1c and high density lipoprotein cholesterol (r = -0.63) and a direct correlation between haemoglobin A1c and low density lipoprotein cholesterol (r = 0.35) and triglycerides (r = 0.62) in the male diabetics. The findings were similar in females. The most striking change was observed in low density lipoprotein cholesterol levels, which were more markedly increased in poorly controlled females than in poorly controlled males. No statistical singificant differences were found between the groups in good and fair control for any of the plasma and lipoprotein lipids studied. A significant difference however was found between the groups in poor and fair control. There was a significant correlation in females between haemoglobin A1c and low density lipoprotein cholesterol levels (r = 0.43), haemoglobin A1c and triglycerides levels (r = 0.54) and an inverse correlation between haemoglobin A1c and high density lipoprotein cholesterol (r = -0.59).
121 citations
TL;DR: Comparison of the distribution of callosal axons and transneuronal label suggests that regions of murid cortex similar to areas 18, 19 and lateral suprasylvian cortex in cats may be located posteriorly in area 18a.
TL;DR: In this article, a statistical procedure for the estimation of the parameters of the canonical cusp catastrophe model is presented, which is computationally no more complicated than multiple regression, and is based on the method of moments.
Abstract: Before catastrophe models can achieve scientific legitimacy, they must be subjected to empirical tests with real data. This research report provides the details of a recently developed statistical procedure for the estimation of the parameters of the canonical cusp catastrophe model. The procedure is computationally no more complicated than multiple regression, and is based on the method of moments. As an example of the use of this estimation technique, it is shown that extroversion can be used as a splitting factor in the prediction of driving speed after the ingestion of alcohol. This is an example in which catastrophe theory supplies a nontrivial and successful description of the effect of a higher-level system characteristic (extroversion-introversion) on a lower-level measure of system performance (driving speed). Of course, catastrophe models can be used in and between all system levels.
TL;DR: Samples of human cerebral cortex were obtained from twelve autopsied patients with Alzheimer's disease or “normal” aging and a hypothesis concerning the role of NF proteins in senile cerebral amyloid is presented.
Abstract: Samples of human cerebral cortex were obtained from twelve autopsied patients with Alzheimer's disease or "normal" aging. Rabbit or goat anti-human antisera to the following plasma proteins: IgG, F(ab')2, Fc, kappa and lambda light chains, IgM, IgA, fibrinogen, albumin, C3, lysozyme, haptoglobin, macroglobulin, and microglobulin; antibodies to the following intracellular proteins: glial fibrillary acidic (GFA) protein, filamin, actin, non-muscle myosin, tubulin, cholinergic vesicle proteins, and neurofilament (NF) proteins were utilized in the immunoglobulin peroxidase bridge. Amyloid cores of classical or perivascular plaques and dyshoric angiopathy exhibited a strong reaction for intact IgG and for both of its light chains, moderate reactions for lysozyme, fibrinogen, albumin and IgA, and weak reactions for IgM, C3, Fc, F(ab')2, haptoglobin, macroglobulin and microglobulin. Antibodies to all three NF proteins, individually and pooled, stained dyshoric and plaque amyloid, while antibodies to other intracellular proteins did not. The coronae of classical plaques and many primitive plaques stained for GFA, but inconsistently for IgG, both light chains, lysozyme, actin, tubulin, and NF proteins. Affected vessels of three patients with Congophilic angiopathy were reactive for all plasma proteins (especially IgG, fibrinogen, and albumin) and for NF proteins. NF staining in Congophilic blood vessels, although variable, revealed a peripheral or adventitial distribution, whereas plasma proteins tended to be localized in the media of the vessel wall. The distributions of Congo red and NF positivity were often identical. Both NF and Congo red staining was sensitive to oxidation. Isolated NF proteins were Congophilic and capable of displaying apple-green birefringence. A hypothesis concerning the role of NF proteins in senile cerebral amyloid is presented.
TL;DR: Intraocular HRP injections in E16-21 embryos show that during the normal development of the central optic projections in hooded and albino rats many optic axons grow through the chiasm into the contralateral eye, but this retino-retinal projection disappears shortly after birth.
TL;DR: It is important to realize that disruption of the menstrual cycle, ranging from mild changes in flow to amenorrhea, is a relatively common problem for the female athlete engaged in strenuous endurance sports, and no evidence exists at present to indicate conclusively that this menstrual dysfunction is harmful to thefemale athlete's reproductive system.
TL;DR: The maturation of tectal tissue transplanted from fetal rats to the midbrain of newborns is examined and the distribution of host retinal and cortical afferents within the transplants are characterized.
Abstract: We have examined the maturation of tectal tissue transplanted from fetal rats to the midbrain of newborns and have characterized the distribution of host retinal and cortical afferents within the transplants. The transplants develop characteristic internal order and connections which distinguish them from either embryonic cortex or retina placed in the same region. Host retinal afferents project to clearly circumscribed regions, where they synapse mainly on small dendrites or dendritic spines, and only rarely on vesicle-containing profiles. The retinorecipient areas contain few stained axons in neurofibrillar preparations and are almost always located at the surface of the transplant. There is very little overlap in the input from the two eyes into a single transplant even though the projections from each eye may lie adjacent to one another. Cortical afferents spread more broadly in the transplants, but are largely absent from areas of optic termination and from other more deeply located regions with sparse fiber staining properties. The observations suggest that when placed close to its normal location, tectal tissue can develop a number of features characteristic of normal superior colliculus. Appreciation of the internal order of the transplants makes it possible to investigate the cortical and retinal afferent pathways usingmore » physiological techniques.« less
TL;DR: The results suggest that plasmapheresis combined with immunosuppressive drug therapy may find a place in the management of patients with moderate to severe scleroderma, and implicates circulating factors in the pathogenesis of the disease.
Abstract: In an uncontrolled clinical trial, plasmapheresis combined with prednisone and cyclophosphamide therapy produced clinical improvement in 14 of 15 scleroderma patients with varying degrees of skin and internal organ involvement. All improved patients showed a gradual loosening of hide-bound skin, relaxation of contractures, and healing of cutaneous ulcers, when present. Severe gastrointestinal symptoms were ameliorated in 4 patients, severe polymyositis was largely reversed in 2 patients, and pulmonary and cardiac function was improved in others. After initial improvement, however, 2 patients died during the period of study and another withdrew unimproved. Antinuclear antibody (ANA) liters declined relatively more than total IgG levels with plasmapheresis in 6 of the 9 patients who had elevated titers. Increased levels of endothelial cell cytotoxic activity found in 11 of the 15 patients were significantly reduced by plasmapheresis. Elevated levels of circulating immune complexes were found in only 4 of the 15 patients. Skin biopsies from adjacent sites taken before and after plasmapheresis in 10 patients all showed less swollen dermal collagen with increased ground substance between collagen bundles in the second biopsy. Although the effects of plasmapheresis cannot be dissociated from those of the immunosuppressive drug therapy, our results suggest that plasmapheresis combined with immunosuppressive drug therapy may find a place in the management of patients with moderate to severe scleroderma. This study implicates circulating factors in the pathogenesis of the disease.
TL;DR: During this five-year investigation separate outbreaks of nosocomial infections that were caused by different bacterial species were shown to be related by the presence of plasmids that contained a common transposable DNA sequence.
Abstract: At the Vanderbilt University Medical Center, Nashville, Tennessee, resistance to gentamicin was encountered with increasing frequency among several species of gram-negative bacilli between 1973 and 1977. Representative strains were screened for plasmid DNA content using agarose gel electrophoresis. In strains of Pseudomonas aeruginosa and Serrati marcescens isolated early in the outbreak, gentamicin resistance was mediated by a common 9.8-megadalton nonconjugative plasmid. Either an 80- or a 100-megadalton transferable plasmid coexisted with the nonconjugative plasmid in the isolates of Serratia. Transposition between the 100- and 9.8-megadalton plasmids in this species resulted in the formation of a 105-megadalton conjugative plasmid that mediated gentamicin resistance; this was observed in strains of Serratia and Klebsiella isolated in 1976-1977. Thus, during this five-year investigation separate outbreaks of nosocomial infections that were caused by different bacterial species were shown to be related by the presence of plasmids that contained a common transposable DNA sequence.
TL;DR: Between June 1977 and December 1978, occult testicular leukemia (OTL) was discovered at three years of continual complete remission (CCR) from the time of diagnosis of acute lymphoblastic leukemia (ALL) in 5 of 59 males undergoing bilateral wedge testicular biopsy at 1 of 15 participating Southwest Oncology Group (SWOG) institutions.
Abstract: Between June 1977 and December 1978, occult testicular leukemia (OTL) was discovered at three years of continual complete remission (CCR) from the time of diagnosis of acute lymphoblastic leukemia (ALL) in 5 of 59 (8.5%) of males undergoing bilateral wedge testicular biopsy at 1 of 15 participating Southwest Oncology Group (SWOG) institutions. Forty-six of the 54 males with normal biopsies (78% of the total group of 59) have remained free of recurrent ALL at a median of 18 months (range 13 to 23 months) since the biopsy procedure, whereas eight have relapsed for the first time--five bone marrow (BM), one sclera, one simultaneous BM and testes, and one testes--at a median of 12.5 months (range 4 to 22 months) after the normal testicular biopsy. With aggressive therapy after biopsy in the five boys with OTL, one has died 19 months after biopsy (after two BM relapses), one is alive 21 months after biopsy (after two BM relapses), and three are alive and free of recurrent ALL 13, 16, and 19 months, respectively, since the diagnosis of OTL.
TL;DR: The plastic wrap/culture tripod technique described in this paper allows normal embryonic growth and differentiation from 48 hours (in ovo pre‐incubation age) through at least 10 days of total incubation.
Abstract: Shell-less culture involves culturing chick embryos with associated yolk and albumen outside of the eggshell and shell membranes. The technique allows direct access to and continuous observation of cultured embryos almost to the time of hatching. The plastic wrap/culture tripod technique described in this paper allows normal embryonic growth and differentiation from 48 hours (in ovo pre-incubation age) through at least 10 days of total incubation. As the duration of in ovo pre-incubation is decreased below 36 hours, there is a concomitant increase in the percentage of grossly abnormal embryos associated with decreased survival and retarded growth and differentiation. Survival of embryos pre-incubated for 72 hours through 13 and 18 days of total incubation is greater than 80% and 40%, respectively. The wrap/tripod technique allows substantially better survival and more normal development of cultured embryos than does the petri dish technique of Auerbach et al. (1974). Embryonic growth in 7.8-cm-diameter chambers is significantly greater than in either larger (10.6 cm) or smaller (5.2 cm) diameter chambers. Some gas exchange through the culture chamber walls appears necessary for optimal embryonic survival and growth. Suspending egg contents in either Safeway or Handi-Wrap plastic wrap (both of intermediate permeability) in 7.8-cm tripods resulted in superior growth and/or survival compared to suspension in Silastic sheeting (high permeability), Saran Wrap (low permeability), glass dishes (nonpermeable), or glass dishes lined with an inner layer of Safeway wrap(nonpermeable).
TL;DR: A clinically feasible method to provide objective, quantitative information regarding the quality of a patient's gait is presented and the technique used is simple and economical and requires minimal equipment.
Abstract: The purpose of this paper is to present a clinically feasible method to provide objective, quantitative information regarding the quality of a patient's gait. The technique used is simple and economical and requires minimal equipment. The four basic temporal and distance factors are 1) stride length, 2) step length, 3) cadence, and 4) velocity. The technique requires the following equipment: 1) grid pattern, 2) stop watch, 3) portable tape recorder, 4) tape measure, 5) marking pen, and 6) masking tape. Case examples are provided to demonstrate the use of the data obtained.
TL;DR: Ear-canal sound pressure and cochlear potentials were monitored inthe anesthetized gerbil to study the origins of acoustic emissions produced by transient and continuous stimuli, and strong acoustic and CM distortion products occurred when two primary tones of moderate levels were presented to the ear.
TL;DR: The results suggest that an age-related antigenic determinant(s) present on senescent human RBC is exposed by desialylation of the major sialoglycoprotein component of the RBC membrane.
TL;DR: A hydrophila is becoming more commonly recognized as a lethal pathogen and should be sought when gram negative infection is suspected and one patient survived severe ARDS and gram-negative sepsis.
TL;DR: The lag time between inoculation and onset of diarrhea was probably due to the need for the bacteria first to attach to and then colonize the Peyer's patch lymphoid follicles, and the intestinal mucosa was probably colonized by bacteria shed from the Peyers's patches.
Abstract: A strain of Escherichia coli (RDEC-1) has been described that in rabbits colonizes the intestine; adheres to mucosal epithelial cells of the ileum, cecum, and colon; and causes diarrhea by an unknown mechanism. This study attempted to determine the location of the bacteria in the rabbit intestine during the unexplained six- to seven-day interval between bacterial inoculation and onset of diarrhea. Specimens of ileum, cecum, colon, ileal Peyer's patches, sacculus rotundus, and appendix from control rabbits and from rabbits killed at intervals after inoculation with RDEC-1 bacteria were examined by light and direct fluorescence microscopy. Bacteria in large numbers attach to the tips of the Peyer's patch lymphoid follicles by 24 hr, but they did not attached to ileal, cecal, or colonic mucosa until three days after inoculation. The lag time between inoculation and onset of diarrhea was probably due to the need for the bacteria first to attach to and then colonize the Peyer's patch lymphoid follicles. The intestinal mucosa was probably colonized by bacteria shed from the Peyer's patches.
TL;DR: Sperm antibody (AB) titers, determined by passive hemagglutination and cytotoxicity assays, were found to be elevated in 62 males and 46 females of 103 couples with primary infertility; 15 males and 12 females of 25 couples with secondary infertility; 10 males and 8 females of 18 couples with histories of repeated abortion; 21 males and 17 females of 24 couples in which the husband had a history of prostatitis; and 29 males and 18 females of 38 couples with oligospermia.
TL;DR: Analysis of the data demonstrated that the group receiving multiple family therapy had a larger continuous time of naltrexone ingestion and remained in the treatment program longer than clients who did not receive multiple family Therapy.
TL;DR: The stages of attachment of RDEC-1 bacteria to mucosal epithelial cells were examined using high-voltage electron microscopy of thick sections of ileum and cecum of rabbits with diarrhea to demonstrate several stages of bacterial attachment.
Abstract: RDEC-1 is a strain of Escherichia coli that, in rabbits, attaches to intestinal mucosal epithelial cells bereft of microvillar borders and causes diarrhea by an unknown mechanism. The stages of attachment of RDEC-1 bacteria to mucosal epithelial cells were examined using high-voltage electron microscopy of thick (0.5-micrometers) sections of ileum and cecum of rabbits with diarrhea. The tissues were stained with ruthenium red or antisera to strain RDEC-1 OK antigens. Micrographs, including stereopairs, demonstrated several stages of bacterial attachment. Bacteria were attached to the glycocalyxes of epithelial cell microvilli and to pedestal-like extrusions of the surfaces of epithelial cells lacking microvilli. Structures consistent with bacterial pili were rarely visualized. Attachment to microvilli appeared to be a result of the interaction of polysaccharides of the microvillar glycocalyx and the K antigen of the bacterial capsule.
TL;DR: It is concluded that 7-IHA is a specific inhibitor of Platelet thromboxane synthesis which at the same concentrations does not inhibit arachidonic acid induced platelet aggregation and that inhibition of platelet TXA2 synthesis by throm boxane synthetase inhibitors may not necessarily inhibit arACHidonic Acid induced platelets aggregation.
TL;DR: Electron micrographs provide the most convincing evidence to date to support the hypothesis that myelin figures may be the vehicle whereby the cell rids itself of specific hepatotoxic substances.
Abstract: Livers from mature female rats exposed for up to 36 weeks to dietary levels of Aroclor® 1242 (75 or 150 ppm) and/or commercial grade DDT (75 or 150 ppm) were compared to those from animals receiving basal diets. In earlier studies, reproductive effects of the test substances were assessed. Moreover, the markedly abnormal gross appearance of the livers led to examination of the hepatic effects of PCB and DDT in more detail, at both the light microscope (LM) and electron microscope (EM) levels. Light microscopy revealed focal liver cell necrosis in rats fed PCB, DDT, and PCB-DDT combinations. Higher levels of PCB (150 ppm) increased the severity of necrosis. Feeding both DDT and PCB produced similar effects at 75 ppm, and caused atypical centrolobular regeneration, occasionally forming nodules resembling small tumors. The experimentally induced injury was associated with the marked accumulation of iron-containing pigment in hepatocytes and Kupffer cells. Electron micrographs demonstrated the presence of whorl structures (myelin figures) within liver cell cytoplasm, and for the first time clearly illustrated the endocytotic expulsion of these membranous whorls from hepatocytes into the bile canaliculi and sinusoids. Other ultrastructural changes were similar to those previously reported in rat livers injured by several hepatotoxic substances. Mitochondria enclosed by or projecting into large non-lipid vacuoles were present in several experimental groups. The electron micrographs provide the most convincing evidence to date to support the hypothesis that myelin figures may be the vehicle whereby the cell rids itself of specific hepatotoxic substances.