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101.
A previously undescribed cause of abnormal uterine bleeding is presented. Nine of 310 women evaluated by sonohysterography for abnormal bleeding demonstrated an 8 to 17 mm gap in the anterior lower uterine segment myometrium at the site of prior cesarean deliveries. All women were premenopausal and had a history of 2 to 12 days of postmenstrual spotting. Presumably a lack of coordinated muscular contractions occurs around the cesarean scar, allowing the defect to collect menstrual debris. Subsequently, the debris leaches out through the cervix for several days after the majority of menstrual flow has ceased.  相似文献   
102.
The primate orbitofrontal cortex is a site of convergence of information from primary taste, olfactory, and somatosensory cortical areas. We describe the responses of a population of single neurons in the orbitofrontal cortex that responds to fat in the mouth. The neurons respond, when fatty foods are being eaten, to pure fat such as glyceryl trioleate and also to substances with a similar texture but different chemical composition such as paraffin oil (hydrocarbon) and silicone oil [Si(CH3)2O)n]. This is evidence that the neurons respond to the oral texture of fat, sensed by the somatosensory system. Some of the population of neurons respond unimodally to the texture of fat. Other single neurons show convergence of taste inputs, and others of olfactory inputs, onto single neurons that respond to fat. For example, neurons were found that responded to the mouth feel of fat and the taste of monosodium glutamate (both found in milk), or to the mouth feel of fat and to odor. Feeding to satiety reduces the responses of these neurons to the fatty food eaten, but the neurons still respond to some other foods that have not been fed to satiety. Thus sensory-specific satiety for fat is represented in the responses of single neurons in the primate orbitofrontal cortex. Fat is an important constituent of food that affects its palatability and nutritional effects. The findings described provide evidence that the reward value (or pleasantness) of the mouth feel of fat is represented in the primate orbitofrontal cortex and that the representation is relevant to appetite.  相似文献   
103.
The frog intermediate lobe consists of a single endocrine cell type, the melanotrope cells, which are under the tonic inhibitory control of dopamine. Separation of dispersed pars intermedia cells in a Percoll density gradient has revealed the existence of two melanotrope cell subpopulations, referred to as high-density (HD) and low-density (LD) cells. The aim of the present study was to investigate the effects of dopamine on each of these melanotrope cell subsets. Increasing doses of dopamine, ranging from 10(-9)-10(-6) M, inhibited the release of alpha-melanocyte-stimulating hormone (alpha-MSH) in LD (but not in HD) melanotrope cells. In addition, dopamine provoked a significant reduction of the rate of acetylation of alpha-MSH in LD cells but not in HD cells. Similarly, dopamine significantly decreased the accumulation of POMC messenger RNA in LD cells, whereas it did not affect POMC gene expression in the HD melanotrope subset. On the other hand, microfluorimetric studies revealed that dopamine induced a significant reduction of KCl-stimulated cytosolic free calcium concentration in both LD and HD cells. The present study provides additional evidence for functional heterogeneity of melanotrope cells in the frog pars intermedia. Because dopamine plays a pivotal role in the regulation of alpha-MSH secretion, these data suggest the involvement of cell heterogeneity in the physiological process of background color adaptation in amphibians.  相似文献   
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We reviewed all the cases of Squamous Cell Carcinoma in people under 40 years of age, diagnosed histologically at the Dermatopathology Laboratory of the Santa Maria Hospital, from January 1985 to December 1993. The 19 cases detected were analysed for age, sex, occupation, anatomical site of the tumor, evolution, smoke and alcoholic habits, skin phototypes, immunosuppression, previous viral infections, previous radiotherapy or PUVA therapy and associated diseases. A prevalence of an occupation involving more exposure to the sun was found. Males were more affected than females (2.2/1). In 37% of the patients we detected heavy alcoholic habits. The most frequent anatomical site was the lower lip (42%). Patients with skin phototype I were more affected (53%).  相似文献   
106.
Bronchiolitis obliterans, a form of chronic allograft rejection characterized by progressive fibrous obliteration of the airways, is the major obstacle limiting prolonged survival of lung transplant recipients. To date, no effective therapy against this fatal complication exists. Interleukin-10 (IL-10), an anti-inflammatory and immunosuppressive cytokine, inhibits various T cell and antigen-presenting cell functions. We examined the effect of IL-10 in an animal model for bronchiolitis obliterans. A heterotopic tracheal transplant model was used. IL-10 was administered to the recipient either in its recombinant form by osmotic minipump or by adenoviral-mediated IL-10 gene transfer (Ad5E1mIL-10). Successful gene transfection and expression was confirmed by measuring circulating IL-10 protein. Tracheal allografts were assessed histologically based on a scoring system. IL-10 administration (in recombinant form or by gene transfer) inhibited the development of fibrous airway obliteration 3 weeks after transplantation in comparison to untreated controls (p < 0.05). This was demonstrated only if the delivery was initiated 5 days after transplantation and not if it was started at the time of transplantation. A single administration of the gene construct was sufficient to achieve the desired effect. We have shown that IL-10 can prevent the development of airway fibro-obliteration in this model. Gene transfection at a site distant from a graft can be used to produce a desired effect on the graft. IL-10 may be of major importance in the control of post-transplant bronchiolitis obliterans. The timing of its administration is critical and further studies are required to determine the mechanisms underlying the observed effects of IL-10.  相似文献   
107.
To analyze protein degradation in mitochondria and the role of molecular chaperone proteins in this process, bovine apocytochrome P450scc was employed as a model protein. When imported into isolated yeast mitochondria, P450scc was mislocalized to the matrix and rapidly degraded. This proteolytic breakdown was mediated by the ATP-dependent PIM1 protease, a Lon-like protease in the mitochondrial matrix, in cooperation with the mtHsp70 system. In addition, a derivative of P450scc was studied to which a heterologous transmembrane region was fused at the amino terminus. This protein became anchored to the inner membrane upon import and was degraded by the membrane-embedded, ATP-dependent m-AAA protease. Again, degradation depended on the mtHsp70 system; it was inhibited at non-permissive temperature in mitochondria carrying temperature-sensitive mutant forms of Ssc1p, Mdj1p, or Mge1p. These results demonstrate overlapping substrate specificities of PIM1 and the m-AAA protease, and they assign a central role to the mtHsp70 system during the degradation of misfolded polypeptides by both proteases.  相似文献   
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