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991.
In the United States over 450,000 participants finished a marathon in 2002. Some of them will present to an Emergency Department (ED) with a variety of gastrointestinal complaints. The diagnosis of ischemic colitis should be considered in patients who present with bloody diarrhea. We describe three patients who presented to our ED with abdominal pain and bloody diarrhea after a marathon. Gastrointestinal complaints with emphasis on mesenteric ischemia and ischemic colitis are discussed.  相似文献   
992.
In the rat, the Na,K-ATPase alpha4 isoform exhibits unique enzymatic characteristics and is important for sperm motility. In this work, we studied expression, localization and function of alpha4 in human spermatozoa. We show two catalytically active Na,K-ATPase alpha polypeptides with different ouabain affinity and identified expression of alpha1, alpha4, beta1 and beta3 isoforms in the gametes. In addition, human sperm presented two Na,K-ATPases composed of alpha4, alpha4beta1 and alpha4beta3. Kinetic analysis of these isozymes produced in insect cells showed that, compared with human alpha1beta1, alpha4beta1 and alpha4beta3 exhibit higher Na(+) and lower K(+) affinity and higher sensitivity to ouabain. These particular enzymatic properties suggested a role for alpha4 in sperm function. Using computer-assisted sperm analysis (CASA), we found that ouabain inhibition of alpha4 significantly decreased percentage sperm motility. In contrast, ouabain did not affect linearity of forward progression, amplitude of lateral head displacement, beat cross frequency and sperm straight-line, curvilinear or average path velocities. This suggests a primary role of alpha4 in flagellar motility. Accordingly, we found alpha4 in the sperm tail, predominating in the mid-piece of the flagellum. Therefore, similar to the rat ortholog, human Na,K-ATPase alpha4 isoform has a distinct activity that is essential for sperm function.  相似文献   
993.
994.
995.
Malabsorption in psoriatic patients: cause or consequence?   总被引:1,自引:0,他引:1  
OBJECTIVE: The etiopathogenesis of psoriasis is still unclear. Associations between gut and skin diseases are well known, since psoriatic patients show a high prevalence of coeliac disease. Small-bowel abnormalities can cause clinical or, more frequently, laboratory alterations that give rise to malabsorption. The aim of the study was to evaluate the prevalence of malabsorption in psoriatic patients. MATERIAL AND METHODS: Fifty-five (29 M, 26 F, mean age 51+/-8 years) psoriatic patients in the Dermatology Centre of our hospital and 65 healthy controls (36 M, 29 F, mean age 47+/-9 years) were screened for malabsorption using a D-xylose test. Psoriatic subjects who resulted positive were further investigated in order to reach a better characterization of the malabsorption using serum antigliadin, anti-endomysium and anti-transglutaminase antibodies, H2 lactulose breath test, the parasitological faecal test and colonoscopy with retrograde ileoscopy. RESULTS: Altered D-xylose absorption was found in 60% (33/55) of psoriatic patients and in 3% (2/65) of controls. Of the former, 6% had coeliac disease, 21% had bacterial overgrowth, 3% had parasitic infections and 1 patient presented eosinophilic gastroenteritis. CONCLUSIONS: Malabsorption was more prevalent among psoriatic patients than among controls. Coeliac disease, bacterial overgrowth, parasitic infestations and eosinophilic gastroenteritis could be possible causes of malabsorption in these patients. Further studies are needed to clarify the pathogenesis and possible causative associations between gut and skin diseases.  相似文献   
996.
997.
Psoriasis is a common inflammatory disease affecting 1% of the Brazilian population. Th17 and Th1cells are involved with the immunopathogenisis of psoriasis. In this article it is discussed the interaction between the innate immunity (especially dendritic cells and keratinocytes) and adaptive immunity (T lymphocytes) in the pathogenesis of psoriasis.  相似文献   
998.
We describe a 73-year-old woman with a long-standing history of annular, hyperkeratotic papules that began on the palms and soles and gradually spread to her trunk, extremities, and face. The clinical presentation and biopsy findings were consistent with PPPD, which is a rare subtype of porokeratosis that begins on the palms and soles and gradually spreads to the trunk and extremities. Owing to the risk of malignant degeneration in porokeratosis, patients should be closely monitored with total body skin examinations. There is no definitive treatment for PPPD. Oral retinoids are sometimes helpful although relapses are common after discontinuation of therapy.  相似文献   
999.
ABSTRACT

The aim of this study was to assess patterns of alcohol consumption and alcohol related problems in a sample of lesbian and gay NYC residents. There were no differences between lesbian (n = 93) and gay (n = 90) subgroups with regard to alcohol use and health related variables. The average number of drinking days reported for the previous 30 day period was 6.87 (SD 7.0) and 16% of the sample reported consuming more than 4 drinks per drinking day. Age, educational level, and feelings of excessive restlessness were associated with alcohol use. Although there have been reports of increased rates of alcohol use and alcohol related problems in the lesbian and gay population, this is not reflected in this sample.  相似文献   
1000.
The cytotoxicity of doxorubicin bound to poly(butyl cyanoacrylate) nanoparticles (Dox-PBCA-NP) was investigated in the rat glioma cell lines GS-9L, F-98 and RG-2. MTT and LDH assays were used as cytotoxic assays. In general, the cytotoxicity of nanoparticle-bound doxorubicin (Dox) was enhanced compared to the free drug in solution. However, responses of the cell lines towards the drug effects were different. In the case of free Dox in solution, this difference correlated with different intracellular concentrations of Dox, which in turn, depended on the level of P-glycoprotein (P-gp) expression in these cell lines. Accordingly, the 9L gliosarcoma (GS-9L) cells, which appeared to be most resistant towards Dox, were characterized by the highest P-gp expression.

Additionally, the influence of surfactants on the cytotoxic effect was investigated at different Dox concentrations. It was shown that the presence of polysorbate 80 (Tween® 80) in the nanoparticle formulation significantly enhanced the cytotoxicity, whereas poloxamer 188 (Pluronic® F68) and poloxamine 908 (Tetronic® 908) had a negligible influence.  相似文献   
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