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991.
992.
993.
It is generally believed that women are more vulnerable to alcohol's toxic effects than men. Studies in male alcoholics have consistently shown reductions in brain glucose metabolism. However, such studies have not been done in female alcoholics. The purpose of this study was to evaluate if similar or worse brain metabolic abnormalities occurred in female alcoholics. For this purpose, we measured regional brain metabolism with positron emission tomography and [18F]fluorodeoxyglucose in 10 recently detoxified female alcoholics and compared it with that in 12 age-matched female controls. There were no differences between alcoholics and control females in regional brain glucose metabolism whether we used regions of interest analysis or statistical parameter maps methods. These results do not support a higher toxicity for the effects of alcohol in the female brain, as assessed with regional brain glucose metabolism, because metabolic values in female alcoholics did not differ from those of controls, whereas metabolic values in male alcoholics are generally lower than those in controls. However, this study is confounded by the fact that the severity of alcohol use in these female alcoholics was less than that of the male alcoholics previously investigated in positron emission tomography studies. Future studies in male subjects with alcoholism of moderate severity are required to address gender differences in sensitivity to alcohol effects in brain metabolism.  相似文献   
994.
The human vas deferens (VD) is often considered simply as a conduit to transfer mature sperm from the epididymis to the ejaculatory duct. The cells that make up the epithelium of the VD, however, exhibit many characteristics of cells found in more complex epithelia, which are involved in absorption and/or secretion. In the present investigation, morphometry was utilized to characterize in detail the changes incurred by the human VD during its development, growth, and aging and to determine if these changes correlate with testicular maturation. In addition, the specific types of keratins present in the epithelial cells were defined, as well as desmin distribution in the muscular layers, during the various phases of the development, growth, and involution of the human VD. Results of the morphometric study are consistent with the interpretation that the development, growth, and aging of the VD are delayed, but parallel to, the identical phases exhibited by the human testis. Further, a differential expression of distinct keratin types was observed in the VD during the various phases examined in this study. Taken together, these two correlations may suggest that the VD is unlikely to function solely as a conduit for sperm. The rationale for this interpretation is as follows: 1) the complex developmental and maturational changes measured in the present investigation in the human VD are common to other absorptive and/or secretory epithelia; and 2) these changes parallel developmental changes observed in other androgen-dependent epithelia of the male reproductive tract, which also function to contribute components to seminal fluid as well as to provide a conduit for sperm.  相似文献   
995.
BACKGROUND: Intra-arterial regional anaesthesia (IARA) may be useful for ambulatory hand surgery in patients with poor veins. This randomized, double-blind study assessed which of the three doses of lignocaine gives the optimal analgesia with a minimum of adverse effects. METHODS: A preservative-free, alkalinized 0.5% lignocaine 1, 2 or 2.89 mg/kg body weight was injected into the radial arteries of 60 adult patients, allocated to three equal groups, to produce anaesthesia for carpal tunnel releases, capsulotomies, tenosynovectomies, palmar fasciectomies, Z-plastics, arthroplastics, arthrodeses etc. RESULTS: Surgical analgesia and motor block were best in group 3 (P < 0.01), whereas injection and tourniquet pain scores were similar in the three groups. Onset of analgesia was similar in all groups, and varied between 2 and 15 min. Cannulation time, surgery start time and tourniquet time were also similar in all groups, as were operating conditions and patient's acceptance of the method. No significant cardiovascular changes were observed after tourniquet release in any of the groups. Plasma lignocaine concentrations were lowest in group 1 (1 mg/kg) (P < 0.001). Five patients in group 1, seven in group 2 and seventeen in group 3 developed small bruises at the cannulation site (P < 0.001). Six patients (two in group 1, three in group 2 and one in group 3) had minor symptoms of lignocaine toxicity after tourniquet release (NS). No other complications were observed. CONCLUSIONS: The highest dose of lignocaine produces best surgical analgesia, without increasing the risk of toxicity. However, many patients receiving this dose will develop bruises at the injection site, and an occasional patient may need supplemental analgesia.  相似文献   
996.
An organ culture chimera system was used to assess the effect of human immunodeficiency virus type 1 (HIV-1) infection on the T cell-generation capacity of precursors derived from human peripheral blood. Peripheral blood mononuclear cells from HIV-1-infected patients and uninfected controls were placed on fetal thymus lobes of NOD/LtSz-scid/scid mice. Blood from the HIV-1-infected patients consistently produced fewer CD4 and CD8 cells compared with blood from controls (P < .01). Addition of zidovudine to the cultures did not alter this profile. Limit dilution experiments suggested that there were fewer functional precursors in the infected patients. These results were not dependent on the patient's level of peripheral CD4 cells; even samples from patients with normal CD4 cell counts were unable to generate T cells in organ cultures. The results are consistent with a loss in the capacity of HIV-1-infected patients to produce functional T cell progenitors in their peripheral blood.  相似文献   
997.
An ongoing developmental project is described that uses the National Library of Medicine (NLM) GRATEFUL MED software on the BITNET network to access the NLM databases. The objective of the project is to improve biomedical communication capabilities to support health professionals in countries where international telecommunication services are limited. After a successful demonstration of the concept, the system was assembled and tested by the University of Chile and NLM. The full impact of this project will be measured at a later time. This paper describes the concept and testing of the system in Latin American countries.  相似文献   
998.
Although stress fractures are well recognized, their frequency, sequelae and complex aetiology are often under-rated. In this case report, we describe an unusual case of simultaneous bilateral stress fractures of the proximal tibial shaft in a young man, exposed to a sudden increase in unaccustomed joint loading due to his part-time occupation. The pathogenesis is discussed.  相似文献   
999.
Borna disease (BD) is a virus-induced immunopathologic disease of the central nervous system in a variety of species from birds to primates and probably in humans. Severe inflammatory reactions lead to tissue destruction and finally to cortical brain atrophy. After experimental infection of the rat, intraparenchymal CD8+ T cells, MHC class I Ags on Borna disease virus (BDV)-infected neurons, and numerous nerve cell lesions were present. Treatment of BDV-infected rats with the mAb OX-8 directed against CD8+ cells inhibited the immunopathologic reactions and reduced MHC class I Ag expression. Neuronal lesions were minimal and no loss of brain substance could be observed. Because BDV has no acute cytopathic effects, we provide evidence that the presence of CD8+ T cells within the brain parenchyma and the expression of MHC class I Ags on neurons play a major role for immunopathologic brain tissue destruction and virus-infected neurons in vivo can be destroyed by T cell-mediated cytotoxicity.  相似文献   
1000.
Botulinum toxin A was used preoperatively to temporarily paralyze the intrinsic laryngeal muscles to hinder movements during the healing period after operation. In addition, toxin was injected into the cricopharyngeal muscle to allow a better passive drainage of the saliva into the esophagus. We treated six patients. Three suffered from chronic aspiration problems after multiple lower cranial nerve lesions, and three patients were apallic (after stroke and major brain injury). Two weeks before scheduled operation, we injected the toxin into the posterior cricoarytenoid muscles, the aryepiglottic muscles, and the vocalis muscle on both sides, as well as the cricopharyngeal muscle. The amount of injected toxin varied between 1.0 and 1.4 mL, equal to 200 to 280 units of botulinum toxin A (Dysport). After a complete palsy of these muscles (controlled by direct electromyography), a closure of the larynx was performed. After laminotomy and exposure of the intralaryngeal structures, the false vocal cords were mobilized and adapted with sutures. Because involuntary movements of the intralaryngeal musculature were absent, primary healing without complications occurred in all cases. Aspiration and related complications disappeared in all patients. In addition, the intensity of patient care could be considerably reduced. Preoperative use of botulinum toxin A allows sufficient laryngeal closure. This procedure is especially useful in the treatment of children and young adults, preserving the ability of later speech rehabilitation because of the return of voluntary movements of the intrinsic laryngeal muscles 6 months after the injection. Furthermore, this technique, as minimal surgical intervention, can be performed in high-risk patients.  相似文献   
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