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31.
Background: Lichen sclerosus (LS) has been identified with increased frequency in families,often associated with HLA markers, mainly DQ7. A genetic co‐etiology seems likely in this setting. Moreover, there is an association of LS with autoimmune disorders, such as the presence of anti‐thyroid peroxidase autoantibodies (anti‐TPO), a hallmark of autoimmune thyroid diseases. Patients and Methods: In 3 families affected by LS, we verified their HLA markers, and identified previously undiagnosed cases of LS and autoimmune disorders. 30 individuals were examined with history, skin biopsy, HLA class I and II typing by PCR‐SSP, and measurement of anti‐TPO, free thyroxine and thyroidstimulating hormones (TSH) levels. Results: There were 8 cases of LS, 50 % of them anti‐TPO+. Autoimmune disorders were found in 40 % (total) and in 87.5 % of those affected. Most common HLA markers were B*15, B*57, CW*03, CW*07, CW*18, DRB1*04, DRB1*07, DRB4*. The three latter have been previously associated with LS. Conclusion: New cases of LS and autoimmune disorders can be detected in first degree relatives of patients with LS. The presence of anti‐TPO antibodies strongly suggests autoimmune thyroiditis. There is intra‐familial association between the haplotype HLA‐B*15 ‐DRB1*04 ‐DRB4* and anti‐TPO,emphasizing their link with thyroiditis. New familial approaches might help to make clear the pathogenesis of LS and its association with autoimmune diseases.  相似文献   
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OBJECTIVE: An epidemiological investigation was conducted to determine risk factors for adverse reactions among patients in hospitals and the possibility of extrinsic or intrinsic contamination of intravenous solutions. DESIGN: A retrospective cohort study was conducted to identify solutions associated with adverse reactions. Implicated lots were cultured for bacteria, and endotoxin concentrations were measured. SETTING: Five hospitals in the state of Pernambuco, Brazil, were investigated from February through March 2002. PATIENTS: Surgical inpatients or outpatients receiving intravenous solutions during the study period. RESULTS: Of 355 surgical patients or outpatients treated at hospitals, 28 (8%) developed illness within a mean of 2.5 hours after exposure to intravenous solutions implicated in adverse reactions; 5 (17.9%) of the case patients died. Laboratory testing of bottles from the lots of Ringer's lactate solution implicated in deaths demonstrated a high mean endotoxin concentration of 88.3 endotoxin units (EU)/mL (range, 9.7-298.0 EU/mL), compared with the permitted limit in Brazil of <0.5 EU/mL. Testing of metronidazole implicated in adverse reactions at another hospital and produced by the same company that manufactured the lots Ringer's lactate solution also showed high endotoxin concentrations (mean level, 8.3 EU/mL [range, 5.0-58.3 EU/mL]). The outbreak was controlled after a national recall of the implicated brand of intravenous solutions. CONCLUSIONS: Case patient status was associated with use of Ringer's lactate solution and metronidazole from large bottles, both of which were produced by the same company. High endotoxin concentrations were demonstrated in unopened bottles of implicated products, which is consistent with intrinsic contamination. The high mortality rate may have been compounded by the fact that clinicians administered additional volumes of contaminated 0.9% isotonic sodium chloride solution in response to hypotension or bleeding to some surgical patients. No additional case patients were identified after a national recall of products, inspection, closure of the implicated company's manufacturing facility, and establishment of random quality-control testing of intravenous solutions.  相似文献   
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Nucleus raphe magnus (NRM) is one of the cellular groups of the brainstem that is involved in the physiologic responses to hypoxia and contains nitric oxide (NO) synthase. In the present study, we assessed the role of NO pathway in the NRM on the hypoxic ventilatory response (HVR) and anapyrexia (a regulated decrease in body temperature). To this end, pulmonary ventilation (VE) and body temperature (Tb) of male Wistar rats were measured before and after microinjection of N-monomethyl-L-arginine (L-NMMA, a nonselective nitric oxide synthase inhibitor, 12.5 microg/0.1 microl) into the NRM, followed by hypoxia. Control rats received microinjection of saline. Under resting conditions, L-NMMA treatment did not affect pulmonary VE or Tb. Typical hypoxia-induced hyperventilation and anapyrexia were observed after saline treatment. L-NMMA into the NRM reduced the HVR but did not affect hypoxia-induced anapyrexia. In conclusion, the present study indicates that NO in the NRM is involved in HVR, exerts an inhibitory modulation on the NRM neurons but does not mediate hypoxia-induced anapyrexia.  相似文献   
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In the routine of a hospital, during my nursing practice of providing care to patients with pain, it was shown to me as reaching beyond a biological sphere included in an existential dimension. Something in this experience disturbed me and I felt the need to understand these people suffering from pain, asking how they understand their pain and what is the meaning of experiencing painful chronic situations. In the attempt to find a way to obtain such understanding, I searched for some ideas stemming from phenomenology. Then, I interviewed the subjects individually based on the central question: "How is your experience with pain? Tell me about this". After the analysis, I was able to understand that pain is a way to narrow the horizon of possibilities and transformations in existence. It is not only the physical body that is ill, but also life is affected in its various dimensions, fundamentally with regard to the family, work and self-relation world.  相似文献   
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To clarify the mechanism of tumorigenesis in papillary thyroid carcinoma (PTC) and ascertain whether genomic changes correlate with histologic features, we conducted a comprehensive molecular evaluation of PTC using comparative genomic hybridization (CGH) and microsatellite instability (MSI) analysis in a set of 17 histologically well-characterized PTC specimens. To our knowledge, this is the first study that evaluates chromosomal and nucleotide instability in the same PTC tumor specimens. Four of 15 samples (27%) had aberrations detected by CGH. All four had a partial or complete gain of chromosome 20, and 3 of 4 had a partial or complete loss of chromosome 13. No MSI was detected in any of the PTC samples (n=16), and all samples examined by immunohistochemistry (n=9) expressed the DNA repair enzymes hmlh1 and hmsh2. All PTC samples with abnormal CGH had vascular invasion or invasion of the thyroid capsule, and there was a significant correlation between the presence of chromosomal aberrations and capsular/vascular invasion (P=0.026). We conclude that although chromosomal and microsatellite instability are uncommon in PTC, tumors with chromosomal aberrations are more likely to be associated with invasion.  相似文献   
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BACKGROUND: Liver disorders are the major manifestations of schistosomiasis mansoni. Factors that account for increased concentrations of cholestasis-indicating enzymes in the hepatosplenic form of the disease are unknown. OBJECTIVE: To assess the correlation between increased gamma-glutamyltransferase serum levels and both the parasitic load and ultrasound alterations in patients with schistosomiasis. PATIENTS AND METHODS: Twenty-five patients with the chronic form of schistosomiasis were assessed for the presence or absence of increased enzymatic levels, for the parasitic load (low x medium/high) and for ultrasound parameters. Furthermore, analysis of prothrombin time and a platelet count were performed. RESULTS: Of the 25 patients, 13 showed increased gamma-glutamyltransferase plasma levels. No significant correlation was found between increased gamma-glutamyltransferase levels and the parasitic load, or between increased enzyme levels and ultrasound alterations. Nor did the prothrombin index or the platelet count differ between the two groups (normal gamma-glutamyltransferase levels and increased gamma-glutamyltransferase levels). CONCLUSION: The parasitic load explains no rise in gamma-glutamyltransferase plasma levels in patients with the chronic form of schistosomiasis, and conventional ultrasound is not a sensitive method to detect the alteration suggested by the increased enzyme level in those patients.  相似文献   
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BACKGROUND: Topical tretinoin has been used for a long time to improve photoaged skin, but this therapy takes quite a few months to show some clinical changes. Because of that, we think tretinoin peeling would be an excellent choice for improvement of photoaged skin. OBECTIVE: Our objective was to show the clinical and histologic modifications of the skin after five sessions of tretinoin peeling. METHODS: The authors studied the clinical and histologic modification that occurred in 15 female patients after conducting tretinoin peeling procedures twice a week in concentrations of 1-5%. Conventional sectioning of punch biopsy specimens was conducted before and after the treatment. RESULTS: Clinical improvement was observed in the skin texture and appearance. Through histologic examinations, a decrease in the corneous layer and an increase in the epidermal thickness were noticed, inducing an improvement of its stratification, as well as the formation of cristae cutis. CONCLUSION: It was concluded that the peeling conducted with serial tretinoin showed good clinical and histologic results, especially for the treatment of photoaged skins I and II, melasma, ephelis, and acne degree I, as well as being practical, quick, and easily accomplished with no side effects.  相似文献   
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