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131.
Recombinant human granulocyte-macrophage colony-stimulating factor (rHuGM-CSF) has been reported to increase the leukocyte count in subhuman primates subjected to total-body irradiation and in patients with the acquired immunodeficiency syndrome. We administered this substance to 19 patients with breast cancer or melanoma treated with high-dose combination chemotherapy and autologous bone marrow support. Groups of three or four patients were treated with 2.0, 4.0, 8.0, 16.0, or 32.0 micrograms per kilogram of body weight per day of glycosylated rHuGM-CSF by continuous intravenous infusion for 14 days, beginning three hours after bone marrow infusion. Total leukocyte and granulocyte recovery was accelerated in these patients as compared with 24 historical controls matched for age, diagnosis, and treatment. Leukocyte counts (mean +/- SD) obtained 14 days after transplantation were 1511 +/- 1003 per microliter in patients given 2 to 8 micrograms per kilogram per day, 2575 +/- 2304 in those given 16 micrograms, and 3120 +/- 1744 in those given 32 micrograms, as compared with 863 +/- 645 per microliter in the controls. No consistent effect on platelet counts was noted. Toxic effects were generally mild and not clearly dose-related in patients given 2 to 16 micrograms per kilogram per day. Edema, weight gain, or myalgias occurred in all patients given 32 micrograms per kilogram; marked weight gain, generalized edema, pleural effusions, and hypotension developed in two patients, one of whom also had acute renal failure. Our results indicate that rHuGM-CSF can accelerate myeloid recovery after high-dose chemotherapy and autologous bone marrow transplantation, over a range of doses that can be tolerated. In this setting the ability to increase the dose is limited by the development of myalgias and fluid retention.  相似文献   
132.
IL-10 has a protective role in experimental autoimmune uveoretinitis   总被引:8,自引:0,他引:8  
The role of IL-10 in the regulation of ocular autoimmune disease was studied in experimental autoimmune uveoretinitis (EAU) elicited in mice by immunization with the retinal antigen interphotoreceptor retinoid binding protein. IL-10-deficient mice were susceptible to EAU, indicating that pathogenesis can occur without presence of IL-10. Treatment of normal mice with IL-10 for 5 days after uveitogenic immunization ameliorated subsequent EAU scores, and down-regulated antigen-specific production of tumor necrosis factor-alpha and IFN- gamma. A concomitant treatment with IL-4 further reduced disease, and resulted in emergence of antigen-specific IL-4 and IL-10 production, as well as in enhancement of the IgG1 antibody isotype. IL-4 by itself was not protective. Only IL-10, but not IL-4, was able to inhibit the function of differentiated uveitogenic T cells in culture. Expression of mRNA for Th1 and Th2 cytokines in the eye during the course of EAU showed that while a Th1 pattern predominated early, IL-10 mRNA expression coincided with down-regulation of the Th1 response and resolution of EAU. Systemic neutralization of IL-10 during the expression phase of EAU resulted in elevated disease scores. Our results suggest that endogenous IL-10 limits expression of EAU and may play a role in the natural resolution of disease. The data further suggest that exogenous IL-10 may be useful in therapeutic control of autoimmune uveitis. While IL-10 by itself is sufficient to suppress Th1 effector development and function, a concomitant administration of IL-4 is required to shift the autoimmune response towards a non-pathogenic Th2 pathway.   相似文献   
133.
Summary A cortico-cancellous flap from the anterolateral aspect of the upper third of the tibia was presented. Sixty lower limbs of fresh cadavers were dissected. The vascular bundle includes the anterior tibial artery and its recurrent collateral branches and recurrent and muscllo periostal arteries. The flap is harvested with the interosseous membrane and can be used either free or pedicled. We used this flap for two patients suffering from pseudarthrosis. Long range clinical and radiological results are good.
Le transfert osseux vascularisé tibial superieur
Résumé Les auteurs décrivent un transfert ostéo-periosté vascularisé, prélevé sur la face antéro-latérale de l'extremité supérieure du tibia. L'étude anatomique porte sur soixante membres inférieurs, conservés au froid. La vascularisation métaphysaire du transfert provient de la branche récurrente tibiale antérieure et de ses rameaux, la vascularisation diaphysaire étant issue des branches musculo-périostiées proximales. Le transfert vascularisé est prélevé avec la membrane interosseuse et peut être pediculé ou libre. L'expérience clinique porte sur deux cas de pseudarthroses multiopérées. Les résultats cliniques et radiologiques sont bons à long terme.
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134.
The second case of virilism as a late manifestation of Bardet-Biedl syndrome (BBS) is described, with endocrine and histological evaluation. Both cases manifested ovulatory cycles and developed virilism in adulthood. Elevated plasma testosterone and 17-OH-progesterone were not suppressed by dexamethasone but were suppressed by medroxyprogesterone acetate. Peripheral and ovarian venous blood obtained at the time of surgery demonstrated a marked gradient for testosterone in both ovaries and for progesterone in the ovary bearing the corpus luteum. Histological evaluation of the ovaries demonstrated bilateral ovarian stromal hyperplasia with focal hyperthecosis. Bilateral ovariectomy resulted in complete correction of the endocrine abnormality, although the established hirsutism remains a mark of previous androgen excess.  相似文献   
135.
Distribution of metastases at necrospy in colorectal cancer   总被引:2,自引:0,他引:2  
A series of 372 necropsies on patients with colorectal cancer (CRC) was examined retrospectively. Patients were excluded if the primary tumour was not removed, if the operation was palliative or if death occurred within three months of operation. Only 43 cases remained after these exclusions and of these six died of intercurrent disease. The 37 remaining patients were all thought to have undergone a curative resection, following which they died with recurrent tumour. They represent the group of patients who might have benefited from adjuvant chemotherapy. The pattern of metastases and the cause of death was examined in these 37 patients. Local recurrence was found more commonly (25 cases, 68 per cent) than hepatic metastases (21 cases, 57 per cent) or metastases at other sites. This finding indicates that excision of the primary tumour must be as complete as possible and that adjuvant therapies must be directed both locally as well as systemically.  相似文献   
136.
We describe a syndrome identified in three consanguineous families who had two and probably four common ancestors five generations ago. The syndrome is characterized by profound dysfunction of the central nervous system, silver-leaden colored hair, abnormal melanosomes and melanocytes, and abnormal inclusion bodies in fibroblasts, bone marrow histiocytes and lymphocytes which appear to represent abnormal lysosomal bodies. Because of the biochemical relationships between melanin-melanosomes and neuromelanin, we think that all the manifestations of the condition are related to and represent pleiotropic effects of a newly identified gene in man in its homozygous state. Biochemical reactions of the cells of these patients indicate presence of tyrosinase in the melanosomes.and show that the substance accumulated in cultured fibroblasts and in the bone marrow histiocytes is a PAS and Oil-red-O positive material but is Oil-red-O negative after extraction; it has the typical reactions of melanin withe the Masson and Fontana stain, but cannot be considered typical melanin, since without stain it is colorless. The ultrastructural studies showed round granules with variable matrix, similar in fibroblast and bone marrow, and with variable intensity of reaction to osmium. This mutation principally affects the neuroectoderm, but also the mesoderm.  相似文献   
137.
Human complement component H was found to modify greatly the binding of C3-coated particles to lymphocytes. We used an experimental model in which lymphocytes were mixed successively with various amounts of H and C3b-coated erythrocytes. At least three mechanisms were postulated to interpret the phenomenon: (i) release of endogenous I by lymphocytes triggered by H through specific binding sites, (ii) cleavage of iC3b by I, promoted by complement receptor type one, and (iii) inhibition of immune adherence by H. Such qualitative and quantitative changes in C3-coated particle recognition by the binding sites might mediate important functions of lymphocytes.  相似文献   
138.
It is well established that modification of lysines in histone molecules correlates with gene expression and chromatin structure. It is not known whether this operates entirely at a local level, e.g. through the recruitment of specific proteins, or whether histone modifications might impact on more long-range aspects of chromatin organization. There is a distinctive organization of chromatin within the nucleus and the chromatin at the nuclear periphery of mammalian cells appears to be hypoacetylated. Previously it had been suggested that inhibition of histone deacetylases by TSA causes a gross remodeling of nuclear structure, specifically the recruitment of centromeric heterochromatin to the nuclear periphery. Here, we have quantified the nuclear organization of histone modifications and the localization of centromeric domains in human cells before and after TSA treatment. TSA alters the nuclear distribution of histone acetylation, but not that of histone methylation. TSA elevates levels of histone acetylation at the nuclear periphery but we see no alteration in the position of centromeric domains in the nuclei of treated cells. We conclude that the distinctive nuclear localization of centromeric domains is independent of histone acetylation.  相似文献   
139.
Previous research suggests that the female sex hormones may moderate cardiovascular and mood responses to cigarette smoking and abstinence. To test this possibility, acute effects of cigarette smoking on cardiovascular reactivity and mood were examined in 12 oral contraceptive users and 12 nonusers across two menstrual phases (early and late cycle). After overnight deprivation, each participant attended two sessions in which they first sham-smoked and then smoked two standard cigarettes, via a quantified smoke delivery system. Oral contraceptive users exhibited larger cigarette smoking-induced increases in heart rate compared with nonusers. In addition, cigarette smoking-induced cardiovascular changes varied with both the phase of the menstrual cycle and oral contraceptive use. No menstrual phase-dependent effects were observed for tobacco withdrawal symptoms, premenstrual symptoms, or moods prior to smoking. Cardiovascular hyperreactivity to cigarette smoke in oral contraceptive users may help explain the mechanisms by which smoking and oral contraceptive use contribute to an elevated risk for coronary heart disease.  相似文献   
140.
Incidental neuroblastoma in infants   总被引:2,自引:0,他引:2  
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