首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   68篇
  免费   1篇
耳鼻咽喉   3篇
儿科学   3篇
妇产科学   1篇
基础医学   8篇
临床医学   2篇
内科学   23篇
神经病学   1篇
外科学   8篇
预防医学   4篇
药学   9篇
肿瘤学   7篇
  2021年   1篇
  2019年   5篇
  2018年   2篇
  2015年   1篇
  2014年   2篇
  2013年   4篇
  2012年   1篇
  2011年   2篇
  2010年   1篇
  2009年   3篇
  2008年   3篇
  2007年   2篇
  2006年   1篇
  2005年   3篇
  2004年   2篇
  2003年   4篇
  2002年   4篇
  2001年   2篇
  2000年   4篇
  1999年   3篇
  1992年   4篇
  1991年   1篇
  1990年   1篇
  1989年   1篇
  1988年   3篇
  1987年   5篇
  1986年   1篇
  1984年   2篇
  1983年   1篇
排序方式: 共有69条查询结果,搜索用时 0 毫秒
41.

Introduction

COPD is a highly prevalent but underdiagnosed disease, due to the limited availability of forced spirometry (FS) in primary care (PC). Microspirometers are inexpensive, easy-to-use devices that can measure FEV6 and FEV1/FEV6, and may help reduce underdiagnosis. The aim of this study was to validate the Piko-6 COPD screening device by demonstrating a good correlation with standard FS.

Methods

FS and Piko-6 determinations were made in 155 patients suspected of having COPD. The correlations, ROC curves, and Youden's index of both methods were compared, taking FS as the gold standard.

Results

FEV1, FVC and FEV6 correlation coefficients and FEV1/FVC and FEV1/FEV6 ratios were 0.87 (CI 0.836-0.909), 0.729 (CI 064-0.795) and 0.947 (95% CI 0.928-0.961), respectively. The ROC curve for FEV1 determined by Piko-6 achieved an area under the curve of 0.86 (95% CI: 0.78-0.92). Youden's index with a cut-off point of 0.70 for FEV1/FEV6 was 0.97.

Conclusions

Piko-6 may be useful for COPD screening in PC. Measurements obtained with this device correlate well with those determined by FS, particularly the FEV1/FEV6 ratio. This, combined with its low cost and ease of use, may contribute to reducing COPD underdiagnosis, although its exact role in the diagnostic process remains to be determined.  相似文献   
42.
43.
44.
Lingual abscess is an unusual condition but it may become a life-threatening entity. It presents as a very painful swelling of the tongue that, in its early stages, can be managed by antibiotic treatment. When the airway is obstructed, drainage is required by an open incision or aspiration with a large bore needle. We report a case who consulted on two occasions for a lingual abscess, which opened spontaneously. Due to the rarity of recurrent cases, the causes, diagnosis and treatments will be reviewed.  相似文献   
45.
46.
47.
Folylpolyglutamyl synthetase (FPGS), partially purified from murine L1210 leukemia and Sarcoma 180 cells and the proliferative fraction of luminal epithelium from mouse small intestine (the site of limiting toxicity to folate analogues), was examined for its ability to utilize various 4-aminofolates as substrates. For tumor-derived FPGS, aminopterin was the most preferred substrate overall, exhibiting the lowest value for apparent Km and highest Vmax. The other analogues and folic acid exhibited nearly 2-fold lower Vmax. Folic acid exhibited a 3-fold higher Km than aminopterin. Alkylation of aminopterin (methotrexate) or carbon for nitrogen substitution (10-deazaaminopterin) at N-10 increased Km 3- to 6-fold, while alkylation at C10 (10-ethyl-10-deazaaminopterin) restored Km to near equivalency with aminopterin. For FPGS derived from proliferative intestinal epithelium, aminopterin was also the preferred substrate, but the value for Vmax (derived with crude cell-free extract) was 6-fold lower than for tumor cell FPGS. Values for Vmax (derived with partially purified FPGS) for the other 4-aminofolate analogues and folic acid were similar (methotrexate) or 2-fold (10-ethyl-10-deazaaminopterin) and 5-fold (folic acid) lower than for aminopterin. The value for Km derived with aminopterin was similar to that derived for either tumor cell FPGS. The value for folic acid was 2-fold higher, and alkylation of aminopterin (methotrexate) or carbon to nitrogen substitution (10-deazaaminopterin) at N-10 with (10-ethyl-10-deazaaminopterin) or without alkylation markedly increased Km (27-, 90-, and greater than 100-fold, respectively, for methotrexate, 10-ethyl-10-deazaaminopterin, and 10-deazaaminopterin). In other studies, it was found that the diglutamate of aminopterin (aminopterin +G1) was a relatively poor substrate for FPGS derived from all three sources compared with methotrexate diglutamate, both in respect to values for Km and Vmax that were measured in each case. Findings with FPGS derived from L1210 cells were confirmed by high-pressure liquid chromatography analysis of product formation during the reaction with the parent compounds. The significance of the results presented here to the question of relative toxicity and therapeutic activity of these analogues is discussed.  相似文献   
48.
49.
The effects of exposure to permethrin on gametes, fertilization and embryonic development were examined in medaka (Oryzias latipes). Following range finding (25, 50, 100, 200 or 300 microg/l) and duration of exposure (0, 120, 144, 168, 192, 216, or 240-h) assays, the relative sensitivity was studied when initiation of exposure to permethrin (100 microg/l, for 192-h) occurred at one of four different stages, i.e., unfertilized egg (0-h), late morula (5-h), early neurula (24-h), and early organogenesis (40-h). The later exposure interval proved the most sensitive. Also, differences were observed in rates of recovery in larvae initially affected following the earliest exposure treatment (0-h, gametes prior to fertilization). Permethrin (100 microg/l) did not affect fertilization success and no lethal effects were observed in embryos. Sublethal effects were primarily observed at hatch. Toxicity endpoints in larvae included: delayed swim bladder inflation; inability of hatchling to respond to stimulus; uncoordinated movements, myoskeletal defects and transient enlargement of gall bladder. These changes were characteristic for all hatchlings exposed to nominal concentrations of 50 microg/l. While certain of the above alterations were reversed within 72-h after hatching, lack of swim bladder inflation and inability to respond to stimuli were two features that persisted with significant incidences. Based on persistence of sublethal effects, results from this work indicate the importance of exposures to gametes and to embryos prior to water hardening. The approach taken herein may better reflect environmental risk conditions than assays limited to exposure of embryonated eggs.  相似文献   
50.
Summary The pharmacokinetics of cefoxitin was studied in 6 healthy volunteers and in 5 patients with a pleural effusion after administration of a single dose of 30 mg/kg i.v. infusion. The serum and pleural fluid concentrations of cefoxitin were determined microbiologically. The elimination half-life of the antibiotic from pleural fluid in all cases was 2–3fold longer than from serum, which shows a difference between the kinetic elimination processes of the antibiotic from the two fluids. The slow elimination of cefoxitin from pleural fluid facilitates its accumulation in this compartment during a multiple dosage regimen.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号