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   1016篇
  免费   37篇
  国内免费   16篇
耳鼻咽喉   26篇
儿科学   25篇
妇产科学   51篇
基础医学   62篇
口腔科学   44篇
临床医学   105篇
内科学   238篇
皮肤病学   9篇
神经病学   70篇
特种医学   84篇
外科学   225篇
综合类   10篇
预防医学   33篇
眼科学   31篇
药学   34篇
肿瘤学   22篇
  2024年   1篇
  2023年   2篇
  2022年   12篇
  2021年   20篇
  2020年   17篇
  2019年   21篇
  2018年   19篇
  2017年   17篇
  2016年   29篇
  2015年   26篇
  2014年   50篇
  2013年   61篇
  2012年   76篇
  2011年   76篇
  2010年   45篇
  2009年   37篇
  2008年   88篇
  2007年   87篇
  2006年   73篇
  2005年   89篇
  2004年   72篇
  2003年   46篇
  2002年   25篇
  2001年   12篇
  2000年   9篇
  1999年   11篇
  1998年   4篇
  1997年   3篇
  1996年   7篇
  1995年   1篇
  1994年   3篇
  1993年   3篇
  1992年   8篇
  1991年   4篇
  1990年   6篇
  1989年   2篇
  1988年   3篇
  1982年   1篇
  1981年   1篇
  1974年   2篇
排序方式: 共有1069条查询结果,搜索用时 15 毫秒
81.
Carotid MR angiography: phase II study of safety and efficacy for MS-325   总被引:3,自引:0,他引:3  
PURPOSE: To evaluate the safety and efficacy of MS-325 in patients suspected of having carotid arterial disease. MATERIALS AND METHODS: Fifty carotid arteries in 26 patients were imaged with three-dimensional spoiled gradient-recalled-echo magnetic resonance (MR) angiography at 5 and 50 minutes after injection of MS-325. MS-325 was administered intravenously as a single dose of 0.01, 0.03, or 0.05 mmol per kilogram of body weight as determined with a dose randomization scheme for four, nine, and 13 patients, respectively. Safety, including clinical laboratory changes and electrocardiographic monitoring, was assessed until approximately 3 days after injection. Conventional contrast agent-enhanced angiography was used as the standard of reference. Independent readers blinded to the dose interpreted the MR angiographic and conventional images. Images were assessed for location and extent of carotid arterial stenosis. RESULTS: There were no severe or serious adverse events. For the determination of clinically significant stenosis (>70%) on the 5-minute images, sensitivity, specificity, and accuracy (P =.07, three-way comparison) were 100%, 100%, and 100%; 63%, 100%, and 88%; and 40%, 75%, and 55% at 0.01, 0.03, and 0.05 mmol/kg, respectively. Sensitivity and specificity for images at 50 minutes after MS-325 administration showed the same trends as the 5-minute images. CONCLUSION: Overall accuracy for MS-325-enhanced carotid MR angiography performed during steady-state conditions of circulating contrast agent approximately 5 minutes after injection was high (88%-100%) at 0.03 and 0.01 mmol/kg. MS-325 was well tolerated at all evaluated doses.  相似文献   
82.
The aim of the present prospective controlled study was to examine the influence of 17beta-estradiol and tibolone on tumor necrosis factor-alpha (TNF-alpha) levels in healthy women with surgical menopause. Forty-five surgically menopausal women were included in the study. Thirty women were randomized to receive tibolone 2.5 mg or 17beta-estradiol 2 mg daily for 16 weeks. Fifteen surgically menopausal women who refused hormone therapy served as controls. Serum was collected from the subjects at baseline and at the end of the study for TNF-alpha assay. Neither tibolone nor 17beta-estradiol showed a significant influence on TNF-alpha level at the end of 16 weeks in comparison with baseline. Although tibolone induced a trend toward decreased level of TNF-alpha (3.30 +/- 0.42 vs. 2.56 +/- 1.94 microg/dl), this was non-significant. The slight increase observed in TNF-alpha level in the control group was also insignificant (3.60 +/- 1.20 vs. 4.10 +/- 0.70 microg/dl). Overall, these results demonstrate no significant effects of either tibolone or 17beta-estradiol on circulating TNF-alpha level in surgically menopausal women. However, the significant difference achieved between the tibolone and control group after treatment is promising and needs to be investigated in trials with longer treatment periods.  相似文献   
83.
Use of the transfemoral route for venous catheterization has been considered contraindicated in patients with inferior vena caval (IVC) filters. The transjugular route has been used instead in such patients when subsequent diagnostic or therapeutic procedures are required. Many radiologists, however, are more accustomed to the transfemoral approach, and may not find the transjugular route a desirable alternative. We describe seven patients with previously placed IVC filters in whom the transfemoral route was used to perform pulmonary arteriography (five patients) or to place additional IVC filters (two patients). After venographic confirmation of caval patency, filters were catheterized under fluoroscopic control and the procedures were performed. All procedures were technically successful; no complications occurred. We believe the transfemoral route to be a safe and feasible approach for performing venous procedures in selected patients with IVC filters, obviating the less familiar and potentially more hazardous transjugular approach.  相似文献   
84.
85.
86.
87.
The only beneficial agent for the treatment of chronic delta hepatitis (CDH) is interferon (IFN). However, there is no consensus on the best dosage or duration of IFN therapy. As ribavirin (RBV) increases the sustained response when added to IFN in chronic hepatitis C, probably because of its immunomodulatory effect, we aimed to investigate the efficacy of 2-year IFN treatment and whether RBV had any additive effect to IFN in CDH. METHODS: Patients (n = 31) with CDH were randomized with a 1:2 ratio as 10 patients (3 females/7 males, age 39 +/- 9) receiving IFN monotherapy (9 MU IFN-alpha2a three times weekly) and 21 patients (8 females/13 males, age 38 +/- 11) receiving IFN plus RBV for 2 years (IFN at the same dosage and RBV at 1000-1200 mg/day). Alanine transferase normalization and hepatitis delta virus (HDV) RNA negativity at the end of treatment and at the end of the follow-up period (at least 6 months following 2-year treatment) were primary endpoints of the study. In addition, virological response and biochemical response were determined separately. RESULTS: Eight of 31 patients (25%) had cirrhosis in liver biopsies. Six patients from the IFN monotherapy group and 12 patients from the combination group had biochemical response. Five patients from the IFN monotherapy group and 11 patients from the combination group had virological response at the end of therapy. Two patients from the IFN group and five patients from the combination group had sustained biochemical response at the end of the follow-up period. Hepatitis B virus (HBV) activations with HBV DNA positivity were observed in two patients (one from the IFN monotherapy group, one from the combination group). Two patients (20%) in the IFN group and five patients (23.5%) in IFN plus RBV group remained as virological responders at the end of the follow-up period (P > 0.05). None of the patients with liver cirrhosis were responsive at the end of the follow-up period. CONCLUSION: Almost 20% of the patients with CDH were responsive to 2-year IFN treatment at the end of the follow-up period and no additional effect of RBV was observed. Patients with advanced liver disease failed to respond to treatment.  相似文献   
88.
BACKGROUND: Behcet's disease (BD) is characterized with remissions and exacerbations. However, to date, there is no study to investigate a possible association of disease activity (active versus inactive disease period) with cardiovascular complications. METHODS: Forty patients with BD were evaluated in both active and in inactive disease period. For the control group 45 healthy volunteers, age and sex matched, were registered. Subjects with at least a 15-day lesion-free period were regarded in inactive disease period, and subjects with any oral, skin, and/or genital lesion was regarded as in active disease period. In each subject coronary diastolic peak flow velocities (DPFV) were measured at baseline and after dipyridamole infusion (0.84 mg/kg over 6 minutes) using an Acuson Sequoia C256 echocardiography system. Coronary flow reserve (CFR) was defined as the ratio of hyperemic to baseline DPFV. RESULTS: CFR values were significantly lower in BD patients compared to the controls (2.57+/-0.50 versus 2.87+/-0.53, P = 0.006). In active disease period, basal DPFV (24.6+/-7.5 versus 27.3+/-6.6, P = 0.019) was significantly higher than in the inactive disease period. In the active disease period hyperemic DPFV (61.7+/-14.9 versus 56.8+/-16.7, P = 0.015) values decreased significantly. Therefore, in the active disease period CFR significantly decreased from 2.57+/-0.50 to 2.09+/-0.46, P<0.001. The only independent predictor of CFR within the active disease period was the disease duration (beta = -0.384, P = 0.012). CONCLUSION: Within the active disease period, coronary microvascular function is more prominently impaired in BD patients. Therefore, BD patients are possibly more vulnerable to cardiovascular manifestations when they are in an active disease period.  相似文献   
89.
90.

Background

Providing sufficient information during a preanesthetic interview may help improve patient understanding and decrease anxiety related to spinal anesthesia. We investigated the effect of video‐based education on anxiety and satisfaction in patients about to undergo spinal anesthesia.

Methods

A total of 198 patients scheduled for minor elective surgery under spinal anesthesia were prospectively enrolled. The State‐Trait Anxiety Inventory (State‐Trait Anxiety Inventory/State and State‐Trait Anxiety Inventory/Trait) questionnaires and visual analog scale were used to measure anxiety levels before the standard anesthesia evaluation was initiated. Then, 100 patients in Group 1 received written, verbal, and video‐based education, whereas 98 patients in Group 2 received only written and verbal instructions regarding spinal anesthesia. Then all participants completed the State‐Trait Anxiety Inventory/State and visual analog scale to evaluate anxiety. Finally, a 5‐point Likert scale was used to measure satisfaction during postoperative period.

Results

No differences were found in the State‐Trait Anxiety Inventory/State, State‐Trait Anxiety Inventory/Trait, or visual analog scale scores between the two groups before the information period. The State‐Trait Anxiety Inventory/State scores evaluating anxiety during the post‐information period were differed in both groups and they found as 36.5 ± 10.0 in Group 1 and 39.6 ± 8.6 in Group 2 (p = 0.033). The 5‐point Likert scale scores to measure satisfaction were stated as 4.5 ± 0.6 in Group 1 and 3.5 ± 1.2 in Group 2 (p < 0.001).

Conclusions

Providing video‐based information during the preanesthetic interview alleviated anxiety and increased satisfaction in patients undergoing spinal anesthesia.  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