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991.
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Background: Aortic stiffness assessed by brachio-ankle pulse wave velocity (baPWV) can be used to predict cardiovascular events. However, baPWV is dependent on blood pressure. Antihypertensive drugs have been reported to reduce baPWV; but it is difficult to determine if this effect is associated with lowered blood pressure or reduced arterial stiffness.Objectives: The primary end point of this study was to assess whether antihypertensive drugs reduce arterial stiffness as estimated by cardio-ankle vascular index (CAVI). The secondary end point was to compare the effects of 2 widely used drugs, the calcium-channel blocker amlodipine and the angiotensin II receptor blocker candesartan, on arterial stiffness.Methods: Between October 2005 and September 2006, consecutive Japanese outpatients with essential hypertension (EHT) (defined as using antihypertensive drugs at screening, systolic blood pressure [SBP] > 140 mm Hg, or diastolic BP [DBP] >90 mm Hg) were assigned to treatment for 24 weeks with either amlodipine (5-10 mg/d) or candesartan (8-12 mg/d). Arterial stiffness was evaluated with CAVI before and after 24 weeks of treatment. Relative change in arterial stiffness from baseline was also compared. The evaluator was blinded to treatment.Results: Twenty patients (11 men, 9 women; mean [SD] age, 62 [10] years) were included in the study. There were no significant differences in clinical characteristics between the 2 groups. At baseline, mean (SD) CAVI was not significantly different in the amlodipine group compared with the candesartan group (8.93 [0.93] vs 8.46 [1.34], respectively). During the 24-week treatment period, mean SBP and DBP decreased significantly in both the amlodipine (14/10 mm Hg; P = 0.006 and P = 0.005) and the candesartan groups (13/11 mm Hg; P = 0.033 and P = 0.005). Amlodipine was associated with a significant change in CAVI from baseline (8.93 [0.93] vs 8.60 [1.50]; P = 0.017), whereas candesartan was not (8.46 [1.34] vs 8.81 [1.20]). The percentage change in CAVI was significantly different in the amlodipine group compared with the candesartan group (−7.14 [8.83] vs 5.85 [16.0], respectively; P = 0.038). After 24 weeks of treatment, the CAVI of the amlodipine group was still numerically larger than baseline CAVI of the candesartan group, although the difference was not statistically significant. Furthermore, there was no significant difference in absolute CAVI between the 2 groups after 24 weeks, but the relative change from baseline was significant in favor of amlodipine. Logistic regression analysis revealed that amlodipine improved CAVI independent of its antihypertensive effect.Conclusion: These data suggest that amlodipine and candesartan had different effects on aortic stiffness estimated by CAVI, despite similar effects on brachial blood pressure after 24 weeks of treatment in these Japanese patients with EHT.  相似文献   
995.
Brack T  Thüer I  Clarenbach CF  Senn O  Noll G  Russi EW  Bloch KE 《Chest》2007,132(5):1463-1471
BACKGROUND: Cheyne-Stokes respiration (CSR) frequently occurs in patients with severe heart failure during sleep and may increase mortality. Daytime CSR supposedly poses an even greater risk, but its prevalence and prognostic importance remain elusive. Therefore, we investigated the circadian prevalence of CSR and its influence on survival in patients with heart failure. METHODS: In 60 consecutive ambulatory patients (mean age+/-SE, 58.0+/-1.5 years; 6 women) with stable severe heart failure (left ventricular ejection fraction, 26+/-1%; New York Heart Association [NYHA] class, 2.6+/-0.1), the breathing pattern was unobtrusively monitored during 24 h of usual activities with a portable respiratory inductive plethysmograph. RESULTS: During nights, 62% of patients had >or=15 periodic breathing cycles per hour; during days, the corresponding prevalence was 16%. CSR prevailed in 32+/-3% of the night and in 10+/-2% of the day, with peaks at 4:00 am, 2:00 pm, and 6:00 pm. Eighteen patients with CSR during >or=10% of the daytime lived shorter without heart transplantation than 42 patients with <10% of daytime CSR (p<0.05) during 836+/-27 days of follow-up. CSR during >or=10% of the daytime was an independent predictor of mortality (hazard ratio, 3.8; 95% confidence interval, 1.1 to 12.7; p<0.05) when controlling for age, sex, brain natriuretic peptide, left ventricular ejection fraction, and NYHA class. CONCLUSIONS: CSR occurs in 62% of patients with severe heart failure at night and in 16% during the day. Since daytime CSR is associated with reduced survival, solely performing sleep studies may not allow to adequately assess prognosis and tailor treatment in patients with severe heart failure.  相似文献   
996.
997.
肝细胞生长因子拮抗剂NK4抑制肿瘤的机制   总被引:1,自引:0,他引:1  
0 引言 肝细胞生长因子(hepatocyte growth factor,HGF)是由间质细胞产生的细胞因子,作用于肿瘤细胞表面的跨膜受体c-Met蛋白,引起肿瘤细胞的浸润、转移,而且HGF对新生血管的生成起促进作用.1997年Date等[1]用胰弹性蛋白酶对重组人HGF进行消化裂解,发现了一种新的全面拮抗HGF生物活性功能的拮抗剂-NK4.  相似文献   
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999.
The objective of this study is to determine if there was a difference in rate of post-transplantation urinary tract infection (UTI) in patients who have an indwelling catheter inserted using sterile versus clean technique. UTI is the most common nosocomial infection in the post-transplantation period. We aim to describe risk factors associated with postoperative UTI in our institution and determine if there was a difference between those who have an indwelling catheter inserted using sterile versus clean technique. Risk factors for UTIs can be divided into recipient, donor, and procedure related factors. While an indwelling urinary catheter increases the risk of infection, it is vital for post-operative fluid balance monitoring. Given the morbidity of UTIs in transplant recipients, a number of studies have investigated modifiable risk factors; however, investigation of the technique of indwelling catheter insertion at the time of renal transplantation is yet to be examined. A retrospective analysis of a contemporaneously maintained database was performed of renal transplant recipients over a 2-year period from 2019–2021. Patients were divided into sterile versus clean technique, defined as the use of sterile gloves, gown and fenestrated drape following a surgical scrub, or sterile gloves alone following the use of alcohol-based hand sanitiser respectively. A p value of <0.05 was considered statistically significant. One hundred sixty-nine patients were included in analysis, with 31 UTIs (18.3%) within 30 days of renal transplantation. Female gender and autosomal dominant polycystic kidney disease were associated with a higher rate of UTI. One hundred twenty-three patients had a catheter inserted via sterile technique, and 46 with clean technique, with no significant difference in rate of post-operative UTI (p = 0.52). Inserting an indwelling catheter either by sterile or clean technique at the time of renal transplantation was not associated with the rate of postoperative UTI within 30 days.  相似文献   
1000.
We report on five SARS-CoV-2 congregate setting outbreaks at U.S. Operation Allies Welcome Safe Havens/military facilities. Outbreak data were collected, and attack rates were calculated for various populations. Even in vaccinated populations, there was rapid spread, illustrating the importance of institutional prevention and mitigation policies in congregate settings.  相似文献   
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