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51.
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Background and purpose:

W/Wv and wild-type murine bladders were studied to determine whether the W/Wv phenotype, which causes a reduction in, but not abolition of, tyrosine kinase activity, is a useful tool to study the function of bladder interstitial cells of Cajal (ICC).

Experimental approach:

Immunohistochemistry, tension recordings and microelectrode recordings of membrane potential were performed on wild-type and mutant bladders.

Key results:

Wild-type and W/Wv detrusors contained c-Kit- and vimentin-immunopositive cells in comparable quantities, distribution and morphology. Electrical field stimulation evoked tetrodotoxin-sensitive contractions in wild-type and W/Wv detrusor strips. Atropine reduced wild-type responses by 50% whereas a 25% reduction occurred in W/Wv strips. The atropine-insensitive component was blocked by pyridoxal-5-phosphate-6-azophenyl-2′,4′-disulphonic acid in both tissue types. Wild-type and W/Wv detrusors had similar resting membrane potentials of −48 mV. Spontaneous electrical activity in both tissue types comprised action potentials and unitary potentials. Action potentials were nifedipine-sensitive whereas unitary potentials were not. Excitatory junction potentials were evoked by single pulses in both tissues. These were reduced by atropine in wild-type tissues but not in W/Wv preparations. The atropine-insensitive component was abolished by pyridoxal-5-phosphate-6-azophenyl-2′,4′-disulphonic acid in both preparations.

Conclusions and implications:

Bladders from W/Wv mice contain c-Kit- and vimentin-immunopositive ICC. There are similarities in the electrical and contractile properties of W/Wv and wild-type detrusors. However, significant differences were found in the pharmacology of the responses to neurogenic stimulation with an apparent up-regulation of the purinergic component. These findings indicate that the W/Wv strain may not be the best model to study ICC function in the bladder.  相似文献   
53.

Background  

Influenza surveillance systems provide important and timely information to health service providers on trends in the circulation of influenza virus and other upper respiratory tract infections. Online dissemination of surveillance data is useful for risk communication to health care professionals, the media and the general public. We reviewed national influenza surveillance websites from around the world to describe the main features of surveillance data dissemination.  相似文献   
54.
Background Renal transplant recipients (RTR) have a well recognized increased risk of cutaneous malignancy. A clinical observation that RTR with skin cancer often had multiple seborrhoeic warts prompted an investigation in RTR into the relationship between seborrhoeic warts and skin cancer and an exploration into potential risk factors for seborrhoeic warts in this population, including infection with human papillomavirus (HPV). Methods This was a case control study involving 308 RTR. Clinical examinations identified seborrhoeic warts. Histological records reviewed to look for evidence of prior cutaneous malignancy. Seroprevalence of antibodies to 34 different HPV types tested using multiplex serology. Odds ratios (OR) calculated using unconditional logistic regression analysis to look for associations between skin cancer, HPV infection and seborrhoeic warts, controlling for potential confounding factors of gender, age and time since transplantation. Results Seborrhoeic warts were associated with non‐melanoma skin cancer [OR = 3.7; 95% confidence intervals (CI) ranging from 1.6–8.9; P = 0.002] when confounding factors of gender, age and time since transplantation were controlled for. There was also an association between seborrhoeic warts and viral warts (OR = 3.0, CI: 1.6–5.4; P < 0.0001), but no association between seborrhoeic warts and infection with single or multiple HPV types. Conclusions Seborrhoeic warts are associated with cutaneous malignancy, but not with any of the HPV types tested. The reasons for this association are unclear. RTR with multiple seborrhoeic warts may require more regular cutaneous examination to monitor for early signs of skin cancer.  相似文献   
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The 12th Congress of the (IPTA) event in Austin, Texas, had over 400 attendees from 40 countries. The attendees included a diverse mix of pediatric transplant professionals from several specialties including physicians, surgeons, scientists, nurses, organ procurement personnel, advance transplant providers, pharmacists, administrators, fellows, residents, and students. The 4-day event featured nearly 200 abstracts, 90 oral presentations, 24 mini oral presentations, and more than 80 poster presentations. All of these presentations encouraged vibrant discussions and supported the exchange of new clinical and basic science information regarding clinical care management, basic science research, socioeconomic, and ethical and organ donation issues relevant to pediatric transplantation. We briefly describe here the highest scored presented abstracts at IPTA 2023 that are divided into two categories: clinical and basic sciences.  相似文献   
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Infants hospitalized for bronchiolitis associated with respiratory syncytial virus are isolated for the duration of their hospitalization. This article reviews whether a negative rapid antigenic test could be used to shorten the duration of isolation measures. Rapid respiratory syncytial virus tests were performed from day 3 on alternate days in all patients hospitalized for bronchiolitis. Isolation measures were removed when the test result was negative. The result of the antigenic test was confirmed by viral culture and polymerase chain reaction. Surveillance of nosocomial cases was performed daily. Forty-one patients were analyzed. On day 3, 51.2% of patients were negative by viral culture and 56.1% were negative by rapid testing. On day 5, a further 26.8% were negative by viral culture and 31.7% by rapid testing. The rapid antigen test had a low sensitivity at 60% and a specificity of 76% compared with viral cultures; therefore this test alone cannot be used to lift isolation measures.  相似文献   
59.
血小板冷藏会使血管假性血友病因子受体复合物(von Willebrand factor receptor complex)聚集成簇。巨噬细胞αMβ2 整合素结合在成簇复合物的GPIbα亚基,导致输注的冷藏血小板被快速清除。因此输注用血小板不能冷藏,但现在的室温保存方式也存在很大缺点。我们已证明αMβ2是一种凝集素,它能识别GPIbα的N-连接葡聚糖上暴露的β-N-乙酰葡萄胺。冷藏血小板的酶促半乳糖苷化阻止了αMβ2的这种识别,延长了有  相似文献   
60.
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