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   966篇
  免费   43篇
  国内免费   8篇
耳鼻咽喉   36篇
儿科学   66篇
妇产科学   38篇
基础医学   86篇
口腔科学   29篇
临床医学   71篇
内科学   216篇
皮肤病学   36篇
神经病学   54篇
特种医学   8篇
外科学   273篇
综合类   6篇
预防医学   20篇
眼科学   33篇
药学   28篇
中国医学   1篇
肿瘤学   16篇
  2024年   2篇
  2023年   11篇
  2022年   17篇
  2021年   36篇
  2020年   23篇
  2019年   26篇
  2018年   29篇
  2017年   22篇
  2016年   38篇
  2015年   44篇
  2014年   38篇
  2013年   47篇
  2012年   65篇
  2011年   60篇
  2010年   31篇
  2009年   39篇
  2008年   69篇
  2007年   82篇
  2006年   63篇
  2005年   54篇
  2004年   57篇
  2003年   26篇
  2002年   37篇
  2001年   32篇
  2000年   39篇
  1999年   10篇
  1998年   8篇
  1997年   6篇
  1996年   1篇
  1994年   1篇
  1992年   2篇
  1989年   1篇
  1987年   1篇
排序方式: 共有1017条查询结果,搜索用时 0 毫秒
11.
12.
New antibiotic options are urgently needed for the treatment of carbapenem-resistant Enterobacteriaceae infections. We report a 64-year-old female with prolonged hospitalization following an intestinal transplant who developed refractory bacteremia due to a serine carbapenemase-producing pandrug-resistant isolate of Klebsiella pneumoniae. After failing multiple antimicrobial regimens, the patient was successfully treated.  相似文献   
13.
Objective: The aim of this study was to evaluate whether exposure to second-hand smoke affected the six-minute walk test (6MWT) of obese non-asthmatic pediatric cases.Methods: Obese pediatric patients (body mass index >95th p) with no existing co-morbidities were included in the study. Smoke exposure was assessed with a self-reported questionnaire completed by the parents. The subjects were divided into two groups: Group 1 consisting of obese children exposed to passive smoking and Group 2 of obese children not exposed to passive smoking. In addition to 6MWT, spirometric flow and volume, including forced expiratory volume in 1 s and peak expiratory flow rate, were also measured in all subjects. The results of the 6MWT were assessed to determine any association with passive smoking.Results: The study included 75 obese pediatric cases (40 male, 35 female) with a mean age of 9.06±0.97 years. The 6MWT results in Group 1 was 501.88±62.12 meters and in Group 2 559.63±72.93 meters. The difference was statistically significant (p=0.001).Conclusions: Passive smoking may negatively affect the respiratory and cardiovascular capacity in obese children, who are already at risk of lower cardiopulmonary function. The evaluation of 6MWT in these pediatric patients may be useful for monitoring and families should be warned about potential problems due to smoking.  相似文献   
14.
Tekin G  Sivri N  Tekin YK  Topal E  Erbay AR  Yetkin E 《Angiology》2012,63(7):552-555
We assessed the clinical echocardiograhic, hematological, and biochemical parameters in patients with dilated cardiomyopathy (DCMP) and control individuals mainly focusing on the mean platelet volume (MPV) in terms of DCMP and left ventricle (LV) thrombus formation. Consecutive patients (n = 251) with DCMP and 266 patients without DCMP were studied. Mean platelet volume was significantly greater in patients with DCMP than in control patients (P < .05 for all comparisons). Comparing DCMP patients with LV thrombus (19 patients, 8%) and without LV thrombus (232 patients, 92%) showed that the prevalence of smokers was significantly higher and ejection fraction was significantly lower in patients with LV thrombus. We have shown that patients with DCMP have significantly higher MPV suggesting more platelet activation and the MPV of patients with DCMP and LV thrombus is comparable to those of patients without LV thrombus.  相似文献   
15.

Purpose

Postoperative hypocalcemia is a frequently encountered complication of thyroid surgery. Since hypocalcemic symptoms are closely associated with sex, the aim of this study is to investigate the effects of sex steroids on muscle tissue under hypocalcemic conditions.

Methods

Six groups consisting of control male (M), control female (F), gonadectomized male (M−), gonadectomized female (F−), estradiol-applied gonadectomized male (MX), and testosterone-applied gonadectomized female (FX) rats were used. Contraction recordings were obtained from soleus muscle flaps. Maximal tension (PT), frequency required for 50% of PT (F50), contraction velocity at F50 (V50), and changes in contraction values (d[PT], d[F50], d[V50]) between normocalcemic and hypocalcemic conditions were calculated.

Results

d[PT], d[F50], and d[V50] were significantly higher in M− and MX groups compared with control M group. Whereas d[PT], d[F50], and d[V50] parameters of the F− group were significantly higher than control F group, d[F50] and d[PT] of the FX group showed no significant change and d[V50] for the FX group was significantly lower. A comparison of control groups showed that d[PT], d[F50], and d[V50] of the F group were significantly higher than those of the M group.

Conclusion

Whereas absence of both testosterone and estradiol caused an increase in hypocalcemia-induced changes in contraction parameters of rat skeletal muscle, presence or application of testosterone clearly stabilized contraction parameters.  相似文献   
16.
The purposes of this study were to detect the prevalence of ownership of a home sphygmomanometer among hypertensive subjects through a nation-wide survey, to investigate parameters affecting ownership of a sphygmomanometer, to compare how home blood pressure monitoring (HBPM) was actually used in daily practice with some aspects of the current guidelines, and to discuss what we implemented to increase the reliability of HBPM in a developing country. A total of 2747 hypertensive patients from 34 cities, representative of the Turkish population, were enrolled in the study. A multiple-choice questionnaire was administered to each participant using the computer-assisted telephone interviewing method. Among 2747 hypertensive patients, 1281 of them (46.6%) had a home sphygmomanometer. Most of the patients were using wrist devices. The factors associated with ownership of a sphygmomanometer were female gender, older age, obesity, higher educational status, higher income level, living in urban areas, awareness of hypertension and anti-hypertensive drug usage. Only 16% of the devices were used on the advice of a physician. The patients learned usage of their device mainly from the sellers and their relatives. The ownership of a home sphygmomanometer is common among hypertensive patients in Turkey, but regular monitoring of blood pressure before physician visits is rare despite common ownership of these devices. Daily practice of HBPM in Turkey was far from the recommendations of the current guidelines. More effort is needed to improve the reliability of HBPM.  相似文献   
17.
18.
19.
Intestinal ischemia/reperfusion (I/R) is a complex phenomenon that causes destruction of both local and remote tissues. The objective of this study was to investigate the possible participation of oxidized low-density lipoproteins (oxLDLs) and inducible nitric oxide synthase (iNOS) expression in renal tissue damage after intestinal I/R. The superior mesenteric artery was blocked for 30 minutes, followed by 24 hours of reperfusion. At the end of the reperfusion period, renal tissues were removed; the presence of oxLDL, superoxide dismutase enzyme activity, malondialdehyde levels, and iNOS expression were evaluated. I/R resulted in positive oxLDL staining in renal tissue. Compared with control rats, tissue from the I/R group showed significantly higher malondialdehyde levels and lower superoxide dismutase enzyme activity. Strong and diffuse iNOS expression was present in the I/R group. Our findings support the hypothesis that I/R of intestinal tissue results in oxidative and nitrosative stress and enhances lipid peroxidation in the end organ. These data show that oxLDL accumulates in rat renal tissue after intestinal I/R. Antioxidant strategies may provide organ protection in patients with reperfusion injury, at least by affecting interactions with free radicals, nitric oxide, and oxLDL. This study demonstrates for the first time that oxLDL may play a role in renal tissue damage after intestinal I/R. Antioxidant strategies may be beneficial for protection from reperfusion injury.  相似文献   
20.
Background and aims. Patients with end stage renal disease (ESRD) have many musculoskeletal abnormalities, including hand dysfunction. The Sollerman test evaluates hand grip function in daily activities. The relationships between Sollerman test (dominant hand) with Duruoz's Hand Index (DHI), Health Assessment Questionnaire (HAQ), and Beck Depression Inventory (BDI) tests have not been investigated previously. The aims of this study are to evaluate hand grip function using the Sollerman test in hemodialysis (HD) patients, correlate this test with other measures evaluating hand function or psychosocial status, and investigate factors that can affect Sollerman test. Methods. One-hundred twenty HD patients (64 male, 56 female, mean age 51 ± 1.4 years, mean duration of HD therapy 5.3 ± 3.7 years) were included in this study. The HAQ, DHI, and BDI scores were determined by standard techniques. All patients underwent the Jamar grip test and Sollerman test for the dominant (D) and non-dominant hand (ND). Results. We found a positive correlation between Sollerman test (dominant hand) with Sollerman test-ND, Jamar-D, and Jamar-ND tests. There were negative correlations between Sollerman test with age, HAQ, BDI, and DHI tests. Conclusions. The relationships between Sollerman test (dominant hand) with DHI, HAQ, and BDI tests have not been investigated previously. This study showed the correlations between the Sollerman test (dominant hand) and other tests (either positive or negative). Psychosocial problems can affect hand functions.  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