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1.
Summary The effects of two types of acute exercise (1 h treadmill running at 20 m· min–1, or 6 × 10-s periods at 43 m · min–1, 0° inclination), as well as two training regimes (endurance and sprint) on the sensitivity of epitrochlearis muscle [fast twitch (FT) fibres] to insulin were measured in vitro in rats. The hormone concentration in the incubation medium producing the half maximal stimulation of lactate (la) production and glycogen synthesis was determined and used as an index of the muscle insulin sensitivity. A single period of moderate endurance as well as the sprint-type exercise increased the sensitivity of la production to insulin although the rate of la production enhanced markedly only after sprint exercise at 10 and 100 U· ml–1 of insulin. These effects persisted for up to 2 h after the termination of exercise. Both types of exercise significantly decreased the muscle glycogen content, causing a moderate enhancement in the insulin-stimulated rates of glycogen synthesis in vitro for up to 2 h after exercise. However, a significant increase in the sensitivity of this process to insulin was found only in the muscle removed 0.25 h after the sprint effort. Training of the sprint and endurance types increased insulin-stimulated rates of glycolysis 24 h after the last period of exercise. The sensitivity of this process to insulin was also increased at this instant. Both types of training increased the basal and maximal rates of glycogen snythesis, as well as the sensitivity of this process to insulin at the 24th following the last training session. It was concluded that in the epitrochlearis muscle, containing mainly FT fibres, both moderate and intensive exercise (acute and repeated) were effective in increasing sensitivity of glucose utilization to insulin. Thus, the response in this muscle type to increased physical activity differs from that reported previously in the soleus muscle, representing the slow-twitch, oxidative fibres in which sprint exercise did not produce any changes in the muscle insulin sensitivity.  相似文献   
2.
Up to 80 % of illness episodes are first defined, diagnosed and treated at the household-level. In the developing world especially, approximately half the population has no access to public health services. It is obvious then that other sources of care will be used. We examined the availability of proprietary drugs in communities, and the extent and reasons for their use in the treatment of childhood malaria on the Kenyan Coast. Retail outlets are extensively used as the first tier of health care for illnesses considered to be mild or mundane. However, the wide range, types and formulations of over-the- counter (OTC) drugs including antimalarials available in these retail outlets constitute a major health hazard. Yet, both users and proprietors of retail outlets know little or nothing about the drugs and thus use or sell them inappropriately. Even, children are treated promptly by purchase of OTC drugs. The policy implications of these findings are discussed.  相似文献   
3.
PURPOSE: Invasive mucinous carcinoma of the ovary (mucinous epithelial ovarian cancer [mEOC]) is a histologic subgroup of epithelial ovarian cancer (EOC). Chemotherapy for mEOC is chosen according to guidelines established for EOC. The purpose of this study is to determine whether this is appropriate. PATIENTS AND METHODS: Women with advanced mEOC (International Federation of Gynecology and Obstetrics stage III or IV) who underwent first-line platinum-based chemotherapy were compared with women with other histologic subtypes of EOC in a case-controlled study. RESULTS: Eighty-one patients (27 cases, 54 controls) treated with platinum-based regimens were analyzed. The response rates for cases and controls were 26.3% (95% CI, 9.2% to 51.2%) and 64.9% (95% CI, 47.5% to 79.8%), respectively (P=.01). The odds ratio for complete or partial response to chemotherapy for mEOC was 0.19 (95% CI, 0.06 to 0.66; P=.009) compared with other histologic subtypes of EOC. Median progression-free survival was 5.7 months (95% CI, 1.9 to 9.6 months) versus 14.1 months (95% CI, 12.0 to 16.2 months; P<.001) and overall survival was 12.0 months (95% CI, 8.0 to 15.6 months) versus 36.7 months (95% CI, 25.2 to 48.2 months; P<.001) for cases and controls, respectively. The hazard ratio for progression and death was 2.94 (95% CI, 1.71 to 5.07; P<.001) and 3.08 (95% CI, 1.69 to 5.6; P<.001), respectively, for mEOC patients as compared with controls. CONCLUSION: Patients with advanced mEOC have a poorer response to platinum-based first-line chemotherapy compared with patients with other histologic subtypes of EOC, and their survival is worse. Specific alternative therapeutic approaches should be sought for this group of patients, perhaps involving fluorouracil-based chemotherapy.  相似文献   
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Viruses use many different strategies to evade host immune responses. In the case of SARS-CoV-2, its Spike mutates rapidly to escape from neutralizing antibodies. In addition to this strategy, ORF8, a small accessory protein encoded by SARS-CoV-2, helps immune evasion by reducing the susceptibility of SARS-CoV-2-infected cells to the cytotoxic CD8+ T cell response. Interestingly, among all accessory proteins, ORF8 is rapidly evolving and a deletion in this protein has been linked to milder disease. Here, we studied the effect of ORF8 on peripheral blood mononuclear cells (PBMC). Specifically, we found that ORF8 can bind monocytes as well as NK cells. Strikingly, ORF8 binds CD16a (FcγRIIIA) with nanomolar affinity and decreases the overall level of CD16 at the surface of monocytes and, to a lesser extent, NK cells. This decrease significantly reduces the capacity of PBMCs and particularly monocytes to mediate antibody-dependent cellular cytotoxicity (ADCC). Overall, our data identifies a new immune-evasion activity used by SARS-CoV-2 to escape humoral responses.  相似文献   
7.
The production of metallo-β-lactamases is the most important strategy by which pathogenic bacteria become resistant to currently known β-lactam antibiotics. The emergence of these enzymes is particularly concerning for the future treatment of bacterial infections. There are no clinically available drugs capable of inhibiting any of the metallo-β-lactamases, so there is an urgent need to find such inhibitors. In this review, an up-to-date status of the inhibitors investigated for the inhibition of metallo-β-lactamases has been given so that this rich source of structural information of presently known metallo-β-lactamases could be helpful in generating a broad-spectrum potent inhibitor of metallo-β-lactamases.  相似文献   
8.

Purpose

The occurrence of portal vascular anomalies in Down syndrome has been sporadically reported in the literature. These rare disorders have a wide spectrum of anatomical and clinical presentations. The aim of this communication was to describe the clinical course, imaging features, and management approaches in patients with this association.

Methods

We conducted a comprehensive search of the databases of the Vascular Anomalies Center and the Department of Radiology at Children's Hospital Boston for patients with Down syndrome and portal vascular anomalies. Medical records and imaging studies of varying modalities were reviewed.

Results

Three children with Down syndrome and portal anomalies (portosystemic shunt, simple arterioportal shunt, complex arterioportal shunt) were managed at our institution. The portosystemic shunt was clinically insignificant and resolved without any intervention. The simple arterioportal shunt was successfully treated with embolization. The complex arterioportal shunt was associated with major congenital cardiac defects and the child ultimately expired despite a decrease in the arterioportal shunting after embolization.

Conclusions

Three is a wide spectrum of clinical and anatomical features of portal vascular shunts in Down syndrome. The management approach should be tailored based on the severity of symptoms. Percutaneous embolization can offer a safe, effective, and minimally invasive alternative to the surgical approach in selective cases.  相似文献   
9.
Abstract  A case report and review of an extraskeletal neuroectodermal tumour of the vagina. Background  Ewing’s sarcoma (ES) and primitive neuroectodermal tumours (PNETs) account for approximately 6–10% of primary malignant bone tumours and, following osteosarcoma, are the second most common group of bone sarcomas in children. Ewing’s sarcoma rarely affects the genitourinary tract. Case summary  We report a rare case of extraskeletal Ewing’s sarcoma diagnosed in a 47-year-old Indian woman presenting with a simple cystic lesion in the posterior wall of the vagina. The histopathology revealed a rare presentation of a primitive malignant extraskeletal neuroectodermal tumour. Conclusion  As our PubMed review found only six previously reported cases of vaginal extraskeletal Ewing’s sarcoma. Presentation as vaginal masses helped in early disease detection.  相似文献   
10.
European Journal of Clinical Microbiology & Infectious Diseases - The purpose of this study was to estimate the impact of pneumococcal conjugate vaccine-13 (PCV-13) introduction into the...  相似文献   
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