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991.
患儿女,4个半月。全身色素斑4个月,起水疱10天。查体:全身弥漫性灰褐色色素斑,表面见较多水疱、大疱及糜烂结痂,尼氏征阴性,Darier征阳性。皮损组织病理检查显示真皮浅层及血管周围见较多单一核细胞浸润,G iem sa染色阳性。诊断为大疱性色素性荨麻疹。  相似文献   
992.
We are able to identify the different risk factors involved in the development of the disorder from a study of the childhood of a schizophrenic patient. More specifically, we will define the perinatal risk factors : season and place of birth, viral exposure during pregnancy and obstetric complications. Developmental factors will also be discussed. Socialisation, language, psychomotor and cognitive development disorders are all developmental difficulties seen during the childhood of the schizophrenic patient. Finally we will finish by discussing a few psychosocial risk factors.  相似文献   
993.
994.
OBJECTIVE: To describe the cumulative incidence of and risk factors for tuberculosis (TB) infection among medical students. DESIGN: In 1999, a cohort study of medical students with negative results (induration < 10 mm) on tuberculin skin test (TST) was performed. Students who had undergone two-step testing in 1998 were retested. SETTINGS: University and teaching hospital and referral center for TB and acquired immunodeficiency syndrome, and the Health Sciences Building of the Medical School of the Federal University of Rio de Janeiro, Brazil. PARTICIPANTS: A sample of 618 consecutive medical students with negative TST results who had been tested 12 months before were approached. Information about sociodemographic characteristics, bacille Calmette-Guérin vaccination history, and potential exposures to TB was obtained using a standardized questionnaire. Four hundred fourteen (67%) students completed the study. Students were at two different levels of their training programs (juniors = no contact with patients; seniors = intensive contact with patients). RESULTS: Of 414 participants, 16 (3.9%; 95% confidence interval, 1.06% to 12.1%) had converted to a positive reaction after 1 year. In a multivariate logistic regression analysis, higher level of clinical training was confirmed to be an independent factor associated with TST conversion (odds ratio, 4.77; 95% confidence interval, 1.01 to 22.46; P= .048). CONCLUSION: Senior medical students are at increased risk of Mycobacterium tuberculosis infection in this setting. Therefore, a program of routine tuberculin skin testing and specific TB infection control guidelines are needed for this population.  相似文献   
995.
996.

Background  

B7-H4, a co-inhibitory molecule of the B7 family, can restrain T cell proliferation, cytokine secretion and the development of cytotoxicity. B7-H4 is expressed in tumor tissues at a higher level than in normal tissues, and has a potential effect to protect tumors from anti-tumor immune responses. This case-control study was carried out to determine the potential influences of B7-H4 gene polymorphisms on the susceptibility and progression of breast cancer in Han women of Northeast China.  相似文献   
997.
998.
999.
OBJECTIVES: To evaluate the diagnostic value of intraoral palpation at the lateral pterygoid (LP) area as part of the physical examination to detect myofascial pain, according to modified research diagnostic criteria for temporomandibular disorders. STUDY DESIGN: Forty-four women composed the myofascial pain group, and 33 symptom-free age-matched were the control group. One examiner calibrated and blinded to group distribution performed 2 intraoral bilateral palpations of the lateral pterygoid. RESULTS: The LP area palpation showed sensitivity and specificity values of 79.55% and 77.27%, respectively, and positive and negative likelihood ratios of 3.50 and 0.26, respectively. CONCLUSIONS: Palpation at the LP area did not reach acceptable values of specificity, and care must be taken when judging positive response to this procedure.  相似文献   
1000.
AIMS: To evaluate the usefulness of plasma hydroxy-metronidazole/metronidazole (OH-MET/MET) ratios as a dynamic liver function test in ethanol abusers with or without liver cirrhosis. METHODS: Metronidazole was administered intravenously for 20 min to healthy volunteers, and to patients with alcohol-induced, non-cirrhotic hepatopathy and liver cirrhosis. Plasma concentrations of metronidazole and hydroxy-metronidazole were measured by high performance liquid chromatography in samples collected 5, 10, 20 and 30 min after the metronidazole infusion. RESULTS: Patients with non-cirrhotic alcoholic hepatopathy had significantly elevated aminotransferase levels compared to healthy volunteers and Child A patients. Child-Pugh C patients had significantly prolonged prothrombin times when compared to healthy volunteers and patients with non-cirrhotic hepatopathy. Metronidazole metabolism, as measured by the OH-MET/MET ratio following the intravenous administration of 500 mg of the drug, was significantly impaired in all ethanol-abusing individuals, including patients with non-cirrhotic alcoholic hepatopathy. CONCLUSIONS: Metronidazole metabolism was impaired in ethanol abusers, even in the absence of liver cirrhosis, indicating that ethanol was capable of affecting liver function in the early stages of alcohol-induced liver disease.  相似文献   
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