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   1625篇
  免费   70篇
  国内免费   1篇
耳鼻咽喉   32篇
儿科学   23篇
妇产科学   14篇
基础医学   179篇
口腔科学   20篇
临床医学   177篇
内科学   334篇
皮肤病学   24篇
神经病学   113篇
特种医学   65篇
外科学   433篇
综合类   10篇
预防医学   130篇
眼科学   3篇
药学   46篇
肿瘤学   93篇
  2020年   14篇
  2019年   17篇
  2018年   20篇
  2017年   14篇
  2016年   20篇
  2015年   17篇
  2014年   27篇
  2013年   54篇
  2012年   52篇
  2011年   60篇
  2010年   29篇
  2009年   39篇
  2008年   81篇
  2007年   78篇
  2006年   64篇
  2005年   71篇
  2004年   67篇
  2003年   75篇
  2002年   63篇
  2001年   43篇
  2000年   62篇
  1999年   49篇
  1998年   25篇
  1997年   15篇
  1996年   20篇
  1995年   19篇
  1994年   24篇
  1993年   23篇
  1992年   41篇
  1991年   42篇
  1990年   42篇
  1989年   26篇
  1988年   38篇
  1987年   25篇
  1986年   33篇
  1985年   27篇
  1984年   22篇
  1983年   20篇
  1982年   17篇
  1980年   11篇
  1979年   26篇
  1978年   17篇
  1977年   13篇
  1976年   17篇
  1975年   10篇
  1974年   15篇
  1973年   14篇
  1972年   12篇
  1971年   10篇
  1967年   19篇
排序方式: 共有1696条查询结果,搜索用时 281 毫秒
51.
52.
Insulin aspart (IAsp), is a rapid-acting analogue of human insulin (HI), for use in the meal related treatment of diabetes mellitus. The degree of glycaemic control achieved by IAsp in comparison with HI after algorithm-driven dose optimisation was tested over 3 months. The prospective, multicentre, randomised, open-label study with parallel groups was performed in 48 centres in 11 countries and included 423 basal-bolus treated patients with Type 1 diabetes. Main outcome measures were blood glucose control assessed by HbA1c, nine-point self-monitored blood glucose profiles, insulin dose, quality of life, hypoglycaemia and adverse events. An algorithm-driven increase occurred in the dose and number of daily injections of basal insulin, particularly in the IAsp group. After 12 weeks of treatment, HbA1c was significantly lower in IAsp compared to HI treated subjects by 0.17 (95% CI 0.30-0.04) (P<0.05). Comparison of the blood glucose profiles showed lower blood glucose levels with IAsp after breakfast (mean 8.4 vs 10.1 mmol/l; P<0.0001) and dinner (8.2 vs 9.3 mmol/l; P<0.01). There were no differences between treatments in the incidence of hypoglycaemic episodes or in the adverse event profiles. The WHO Diabetes Treatment Satisfaction Questionnaire score for perceived hyperglycaemia was lower with Iasp (P=0.005), and patients found the insulin aspart treatment more flexible (P=0.022). The current study underlines the need for optimising the basal insulin regimen in order to take full advantage of the pharmacodynamics of IAsp.  相似文献   
53.
Glucose tolerance and B cell function were assessed in 30 consecutive chronic alcoholic patients without overt diabetes mellitus. Plasma glucose, insulin, and C peptide concentrations were measured during an oral glucose tolerance test. All patients underwent a liver biopsy and an exocrine pancreatic function test (Lundh test). Compared with the controls, the three groups of alcoholic patients (those with histologically normal livers, n = 12; those with steatosis, n = 10; and those with cirrhosis, n = 8) all had a two-fold increase in plasma concentrations of insulin as well as C peptide in the fasting state, despite normal fasting levels of glucose. After oral glucose all groups of patients had elevated plasma levels of glucose, insulin, and C peptide compared with the controls. The C peptide/insulin ratio was similar to that in the controls in all groups of alcoholics. Patients with decreased exocrine pancreatic function (n = 7) had a significantly lower insulin and C peptide response to glucose than the patients with normal exocrine pancreatic function. It is concluded that (1) chronic alcoholics even with histologically normal livers have endogenous insulin resistance, and (2) associated damage to the exocrine pancreas is more common than previously recognized and decompensation of B cell function could be demonstrated in patients with decreased exocrine pancreatic secretion.  相似文献   
54.
55.

Background and objectives

In the United States population, high dietary fiber intake has been associated with a lower risk of inflammation and mortality in individuals with kidney dysfunction. This study aimed to expand such findings to a Northern European population.

Design, setting, participants, & measurements

Dietary fiber intake was calculated from 7-day dietary records in 1110 participants aged 70–71 years from the Uppsala Longitudinal Study of Adult Men (examinations performed during 1991–1995). Dietary fiber was adjusted for total energy intake by the residual method. Renal function was estimated from the concentration of serum cystatin C, and deaths were registered prospectively during a median follow-up of 10.0 years.

Results

Dietary fiber independently and directly associated with eGFR (adjusted difference, 2.6 ml/min per 1.73 m2 per 10 g/d higher; 95% confidence interval [95% CI], 0.3 to 4.9). The odds of C-reactive protein >3 mg/L were lower (linear trend, P=0.002) with higher fiber quartiles. During follow-up, 300 participants died (incidence rate of 2.87 per 100 person-years at risk). Multiplicative interactions were observed between dietary fiber intake and kidney dysfunction in the prediction of mortality. Higher dietary fiber was associated with lower mortality in unadjusted analysis. These associations were stronger in participants with kidney dysfunction (eGFR<60 ml/min per 1.73 m2) (hazard ratio [HR], 0.58; 95% CI, 0.35 to 0.98) than in those without (HR, 1.30; 95% CI, 0.76 to 2.22; P value for interaction, P=0.04), and were mainly explained by a lower incidence of cancer-related deaths (0.25; 95% CI, 0.10 to 0.65) in individuals with kidney dysfunction versus individuals with an eGFR≥60 ml/min per 1.73 m2 (1.61; 95% CI, 0.69 to 3.74; P value for interaction, P=0.01).

Conclusions

High dietary fiber was associated with better kidney function and lower inflammation in community-dwelling elderly men from Sweden. High dietary fiber was also associated with lower (cancer) mortality risk, especially in individuals with kidney dysfunction.  相似文献   
56.
Inorganic nitrate has been shown to reduce oxygen cost during exercise. Since the nitrate-nitrite-NO pathway is facilitated during hypoxia, we investigated the effects of dietary nitrate on oxygen consumption and cardiovascular responses during apnea. These variables were measured in two randomized, double-blind, placebo-controlled, crossover protocols at rest and ergometer exercise in competitive breath-hold divers. Subjects held their breath for predetermined times along with maximum effort apneas after two separate 3-day periods with supplementation of potassium nitrate/placebo.  相似文献   
57.
58.
Objective : The use of heparin-coated surfaces in cardiopulmonary bypass has been shown to decrease the inflammatory response imposed by the contact between blood and artificial surfaces. One would expect this reaction to improve clinical outcome. However, this has been difficult to verify. This investigation is based on an aggregation of two randomized studies from our institution and highlights possible effects of heparin coating on a number of clinically oriented parameters. Design : Departmental analysis of patients subjected to coronary artery bypass surgery using heparin-coated circuits. Cardiopulmonary bypass was employed using either the Carmeda or Duraflo heparin coatings compared with a control. The systemic heparin dose was reduced in the heparin-coated groups (ACT > 250 s) vs control group patients (ACT > 480 s). The effects of heparin coating related to clinical outcome were studied. Results : The use of heparin-coated circuits reduced the mean length of stay in hospital from 7.8 &#45 2.5 to 7.3 &#45 1.8 days ( p = 0.040) and postoperative ventilation time from 9.7 &#45 9.2 to 8.2 &#45 8.5 h ( p = 0.018), blood loss 8 h post surgery from 676 &#45 385 to 540 &#45 245 ml ( p = 0.001), individual perioperative change of haemoglobin loss ( p = 0.001), leukocyte count ( p = 0.000) and creatinine elevation ( p = 0.000), proportion of patients exposed to allogenous blood transfusions 39.2 vs 23.9% ( p = 0.001), postoperative coagulation disturbances 4.4 vs 0.4% ( p = 0.006), postoperative deviations from the normal postoperative course 47.2 vs 36.7% ( p = 0.035), neurological deviations 9.4 vs 3.9% ( p = 0.021) and atrial fibrillation 26.4 vs 18.0% ( p = 0.041). No effects were found with respect to perioperative platelet count, postoperative fever reaction and 5-year survival. Conclusion : Based on several indicators, the use of heparin coating in cardiopulmonary bypass is associated with improved clinical results.  相似文献   
59.
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