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11.
Hypertrichosis lanuginosa (without gingival hyperplasia) is described in a mother and son; the latter also had photophobia, infantile genitalia, growth retardation, hypotension, low IQ and dental abnormalities (hyperdontia, permanence of deciduous and delayed eruption of permanent teeth). Both have normal dermatoglyphics. Some clinical findings are discussed. The presence of this syndrome in a mother and son supports an autosomal mode of inheritance (with variable expressivity). Hypertrichosis lanuginosa is a pure monomultidysplasia and may be classified with the tricho-odontic sub-group of the ectodermal dysplasias.  相似文献   
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Alport's syndrome is characterized clinically by a nonimmune glomerulopathy, often accompanied by sensorineural hearing loss and lens abnormalities, frequently due to mutations in the COL4A5 gene. The association of AS with diffuse leiomyomatosis, a benign proliferation of smooth muscle that occurs most often in the esophagus, trachea, and female genitalia, has been reported. Recently, a deletion involving both the COL4A5 and COL4A6 genes has been reported in four unrelated families. We report an additional case with Alport's syndrome associated with leiomyomatosis carrying a deletion of both COL4A5 and COL4A6 genes. A detailed characterization of the genomic region involved in the deletion event has been performed. Our results demonstrate that the deletion removed exon l of COL4A5 and exons l and 2 of COL4A6. © 1994 Wiley-Liss, Inc.  相似文献   
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Leptin, a peptide hormone normally associated with body weight homeostasis, is implicated in the generation of obesity-induced hypertension. Administration of leptin increases sympathetic nerve activity and blood pressure; however, the neural circuity involved in this pressor effect is not clearly defined. In this review we describe experiments in which pseudorabies virus was injected into the heart, kidney and the vasculature within skeletal muscle to reveal the distribution of neurones in the hypothalamus that project to these cardiovascular tissues. This distribution is compared to the well-documented distribution of leptin receptors. Finally we discuss microinjection studies designed to examine the effect of leptin, in these regions, on sympathetic nerve discharge and arterial blood pressure. Leptin injected directly into the ventromedial hypothalamus, arcuate nucleus and lateral hypothalamic area (particularly the perifornical area) increased lumbar sympathetic nerve activity. In addition, microinjection into the ventromedial hypothalamus and parvocellular paraventricular nucleus increased blood pressure. Our results demonstrate a discrete set of hypothalamic pathways that may underlie the involvement of leptin in obesity-induced hypertension.  相似文献   
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Perception of our own bodies is based on integration of visual and tactile inputs, notably by neurons in the brain's parietal lobes. Here we report a behavioural consequence of this integration process. Simply viewing the arm can speed up reactions to an invisible tactile stimulus on the arm. We observed this visual enhancement effect only when a tactile task required spatial computation within a topographic map of the body surface and the judgements made were close to the limits of performance. This effect of viewing the body surface was absent or reversed in tasks that either did not require a spatial computation or in which judgements were well above performance limits. We consider possible mechanisms by which vision may influence tactile processing.  相似文献   
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To assess the efficacy of quinolones in the prophylaxis of infections in neutropenic patients with acute non-lymphocytic leukemia, and to evaluate the emergence of quinolone resistance in two University Hospitals in Brazil, we retrospectively compared 101 consecutive episodes of neutropenia managed with quinolone prophylaxis between 1989 and November 1993, and 26 previous episodes without prophylaxis, and reviewed the results of in vitro sensitivity of Gram-negative strains to quinolones in the same period. Prophylaxis with quinolones resulted in less episodes of bacteremias (21% vs. 69%, p=10(-7)), including Gram-negative bacteremias (6% vs. 38%, p=10(-5)), with no statistically significant difference in the death rate (18% vs. 31%, p=0.14, 95% confidence interval -6-32). The resistance of Gramnegative strains to quinolones rose from 7% to 18% between 1990 and 1993 (p=10(-5)). The resistance against ceftazidime and amikacin, the agents used in the empirical antibiotic therapy, increased in the same proportion as the quinolones. Given the limited benefit of quinolones as prophylaxis and the increasing number of quinolone-resistant Gram-negative strains observed in our hospitals, the use of quinolones as prophylaxis must be seriously questioned. A stricter control of the use of quinolones in these hospitals might decrease resistance.  相似文献   
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The resistance of cancer cells to anti-neoplastic agents is a major attribute of malignancy. Kinetic drug resistance develops as the tumor burden increases, and is reversible when the cell mass can be reduced. Genetic drug resistance, in contrast, results in the acquisition of possibly irreversible resistance by random cell mutation. The latter mechanism, and one of its corollaries, that rapidly alternating drug regimens could prevent the advent of new resistant cell lines, have been the subject of many studies in the last decade. The endpoint to evaluate in such studies should be an increase in failure-free survival, since such prevention cannot have any influence in the complete remission rates. A review of the clinical trials in Hodgkin's disease suggests that failure-free survival rates are in fact improved with the alternating schedules. On the other hand, dose-intensification is presently under study as a means of overcoming kinetic drug resistance, thereby increasing the complete remission rates, and has recently proved effective in the prolongation of survival in different malignancies. Further understanding of the mechanisms of drug resistance and the prospective appraisal of the combination of both high-dose therapy and alternating drug treatments should result in a better outcome, mostly for patients with large tumor burdens or other high risk factors.  相似文献   
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Two sets of benzotriazinone and benzoyltriazole derivatives were prepared and tested for local anaesthetic activity in comparison with lidocaine. Several of the prepared compounds exhibited a fairly good activity comparable or superior to that of lidocaine. The presence of a benzotriazinone or a benzoyltriazole moiety as an aromatic system was quite profitable for both the intensity and duration of activity. The acute toxicity in mice of the four most potent compounds of the series was also assessed. Compound 1b, which has an anaesthetic activity comparable to that of lidocaine, was also characterized by a more favourable therapeutic index. All compounds were tested in vitro to evaluate their negative chronotropic action in isolated rat right atria.  相似文献   
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