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   242篇
  免费   7篇
  国内免费   13篇
耳鼻咽喉   1篇
儿科学   23篇
妇产科学   12篇
基础医学   32篇
口腔科学   1篇
临床医学   20篇
内科学   49篇
皮肤病学   5篇
神经病学   3篇
特种医学   20篇
外科学   51篇
综合类   9篇
预防医学   18篇
药学   11篇
肿瘤学   7篇
  2021年   3篇
  2019年   6篇
  2017年   2篇
  2016年   3篇
  2015年   2篇
  2014年   5篇
  2013年   9篇
  2012年   10篇
  2011年   14篇
  2010年   13篇
  2009年   8篇
  2008年   12篇
  2007年   21篇
  2006年   10篇
  2005年   10篇
  2004年   4篇
  2003年   11篇
  2002年   3篇
  2001年   10篇
  2000年   4篇
  1999年   7篇
  1998年   10篇
  1997年   6篇
  1996年   2篇
  1995年   2篇
  1994年   3篇
  1993年   2篇
  1992年   3篇
  1991年   4篇
  1990年   8篇
  1989年   3篇
  1988年   3篇
  1987年   3篇
  1986年   3篇
  1985年   5篇
  1984年   2篇
  1983年   3篇
  1982年   7篇
  1981年   3篇
  1980年   3篇
  1979年   2篇
  1974年   1篇
  1972年   2篇
  1971年   2篇
  1970年   2篇
  1969年   1篇
  1968年   2篇
  1967年   1篇
  1935年   1篇
  1931年   1篇
排序方式: 共有262条查询结果,搜索用时 15 毫秒
51.
Endothelin-1 (ET-1) has been shown to have a constrictor effect on the airways and parenchyma; however, the roles of the ETA and ETB receptors in the ET-1-induced changes in the airway and tissue compartments have not been fully explored. Low-frequency pulmonary impedance (ZL) was measured in anaesthetized, paralysed, open-chest guinea-pigs. ZL spectra were fitted by a model to estimate airway resistance (Raw) and inertance (Iaw), and coefficients of tissue damping (G) and elastance (H), and hysteresivity (eta = G/H). Two successive doses of ET-1 (0.05 and 0.2 nmol x kg(-1)) each evoked significant dose-related increases in Raw, G, H and eta. Pretreatment with 20 nmol x kg(-1) BQ-610 (a highly selective ETA receptor antagonist) resulted in a significantly decreased elevation only in H after the lower dose of ET-1. However, all parameters changed significantly less on the administration of ET-1 after pretreatment with 80 nmol-kg(-1) BQ-610, with 20 nmol x kg(-1) ETR-P1/fl (a novel ETA receptor antagonist) or with 20 nmol x kg(-1) IRL 1038 (an ETB receptor antagonist). The results of the separate assessments of the airway and tissue mechanics demonstrate that endothelin-1 induces airway and parenchymal constriction via stimulation of both receptor types in both compartments.  相似文献   
52.
53.
54.
Lorenzo  RL; Bradford  BF; Black  J; Smith  CD 《Radiology》1985,157(1):79-80
Three children aged 17 months to 17 years developed right-sided peripheral lung abscesses. Clinical signs were fever and cough. Laboratory cultures were negative, and the patients did not respond to appropriate antibiotic coverage. Under fluoroscopic guidance, purulent material was removed from the abscesses by needle aspiration. The patients became afebrile within 24 hours; none suffered complications of bleeding or pneumothorax. Cultures of the aspirate were positive for microorganisms sensitive to the prescribed treatments. A simple aspiration technique is described and proposed as useful for selected patients when surgical drainage is recommended. There was no morbidity in our cases, and recovery from a typically prolonged course was shortened by the procedure.  相似文献   
55.
L Varga  L Asztalos 《Orvosi hetilap》1990,131(21):1143-1146
Nicolau syndrome is a rare complication, which occurs after intramuscular injections of various drugs, particularly antirheumatic drugs. During one year, the authors observed this syndrome in three patients, who had received intramuscular injections of Ketazon. The aetiology of the syndrome is not yet known, but it is often caused by accidental intraarterial injections of the drug. Since there is no specific therapy for the syndrome, the authors insist on the possibility of preventing it.  相似文献   
56.
Summary.  TT virus (TTV) genogroup 1 infection has an increased prevalence in solid organ transplant recipients. In this study, the presence of TTV in renal transplant recipients was examined by two PCR methods, one capable of detecting most TTV genotypes (UTR-PCR), the other specific to genogroup 1 (N22-PCR). The N22-PCR detected TTV in 57% (53/92) of the renal transplant patients and in 20% (13/66) of the healthy individuals, while the prevalence of TTV with the UTR-PCR was above 90% in both the control and the patient groups. The N22-PCR was used in longitudinal studies of 31 renal transplant recipients, these PCR products were sequenced and aligned. TTV status was not associated with the patients’ age at transplantation, male to female ratio and the time lag between kidney transplantation and the TTV test. During the follow-up consistent TTV status was found in 26 patients, while two initially TTV positive patients converted to negative and three initially negative patients converted to positive. The TTV variants varied among the tested patients, but were the same in the consecutive samples of each patient, indicating that TTV infection was persistent in renal transplant recipients and novel infection occured rarely in the post-transplant period. Received October 2, 2002; accepted December 27, 2002 Published online March 13, 2003  相似文献   
57.
Kidney transplantation is indicated for end-stage renal disease. Autosomal dominant polycystic kidney disease (ADPKD) causes structural degeneration of the kidney and eventually becomes end-stage renal disease. ADPKD patients usually have several renal and nonrenal complications. We analyzed our kidney transplantation activities between 1991 and 2010 regarding ADPKD. We followed up with patients to December 31, 2016. Data were collected as patient and graft survival rates, the prevalence of polycystic manifestation of the gastrointestinal tract and other organs, and the attendance of urinary tract infection. Among the 734 kidney transplantations, 10.9% (n = 80) had an ADPKD. Four patients (5%) had diverticulum perforation. The prevalence of post-transplantation urinary tract infection was higher in ADPKD patients (55.9%) compared to non-ADPKD patients (44.1%). The 1-, 3-, and 5-year overall survival rates in ADPKD recipients versus non-ADPKD patients are 77.5%, 70.0%, and 67.5% versus 86.4%, 83.0%, and 80.1%, respectively. Patients with ADPKD were transplanted at an elder age compared to others (median: 47.5 years vs. 39.9 years). Female patients had longer graft survival times than males. ADPKD implies multiple cystic degeneration of the kidneys; however, it can cause structural degeneration in other organs. It is typical for ADPKD patients to have an acute abdominal-like syndrome. Immunosuppressive drugs can hide the clinical picture, which makes early diagnosis difficult.  相似文献   
58.
Apolipoprotein (apo) B-48 is the only specific marker of intestinal lipoproteins. We evaluated a novel enzyme-linked immunosorbent assay (ELISA) standardized with recombinant apo B-48 to measure apo B-48 in plasma and triglyceride-rich lipoproteins (TRLs, density <1.006 g/mL). Coefficients of variation were less than 2.5%. Assay values correlated well (r = 0.82, P < .001) with values obtained by gel scanning of TRLs (n = 75 samples); however, the gel scanning method yielded values that were about 50% lower than ELISA values. About 60% to 70% of apo B-48 was found in TRLs. In 12 healthy subjects, median fasting plasma apo B-48 levels were 0.51 mg/dL and were increased by 121% to 147% in the fed state. In 63 obese subjects, median fasting apo B-48 values were 0.82 mg/dL; and feeding resulted in almost no change in total cholesterol, non–high-density lipoprotein cholesterol, or total apo B values, whereas triglyceride, remnant lipoprotein cholesterol, and apo B-48 levels were significantly higher (P < .05; by +73%, +58%, and +106%), and direct low-density lipoprotein cholesterol and direct high-density lipoprotein cholesterol were significantly lower (P < .001, by −13% and −20%) than fasting values. Relative to controls, 270 hyperlipidemic subjects had significantly higher (P < .001, +115%) fasting total apo B and higher apo B-48 values (P = .06, +37%). Our data indicate that the apo B-48 ELISA tested provides highly reproducible results and is excellent for research studies. Median apo B-48 values in healthy subjects are about 0.5 mg/dL and increase more than 100% in the fed state. Elevated levels are observed in obese and hyperlipidemic subjects.  相似文献   
59.
玻璃纤维桩在严重缺损牙齿修复中的应用   总被引:3,自引:1,他引:2  
目的:在自行研制了弹性模量介于牙釉质和牙本质之间的玻璃纤维增强树脂桩的基础上,追踪观察其在严重缺损牙齿修复中的效果。方法:选择2005-08/2006-10在桂林医学院附属医院行桩核冠修复并能配合修复后半年复查的患者69例,用自行研制的直径分别为1.4,1.8,2.1mm的圆柱形玻璃纤维/树脂复合材料桩钉对84个严重缺损牙进行桩核冠修复,其中52个前牙,32个后牙;桩修复体直径为2.1mm者22个,1.8mm者39个,1.4mm者23个。半年后进行临床和X射线复查,桩完好、根完好、核完好及冠未脱落或松动者为纤维桩修复成功;同时观察有无材料宿主反应。结果:84个桩核冠修复体复查有2个桩和1个核松动、脱落,修复成功率为96.4%;前后牙及不同直径桩修复成功率的对比差异无显著性意义(P>0.05);所有利用纤维桩修复缺损患牙的患者均未发现有材料宿主反应。结论:玻璃纤维增强树脂桩的力学性能达到修复要求,桩可通用于各牙位,直径1.4,1.8和2.1mm等3种规格的桩都适用于临床修复。初步证明玻璃纤维增强树脂桩是一种有价值的修复方式,但还需进行更长期和更大样本的临床观察。  相似文献   
60.
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