全文获取类型
收费全文 | 1503篇 |
免费 | 79篇 |
国内免费 | 3篇 |
专业分类
耳鼻咽喉 | 54篇 |
儿科学 | 71篇 |
妇产科学 | 58篇 |
基础医学 | 134篇 |
口腔科学 | 41篇 |
临床医学 | 112篇 |
内科学 | 452篇 |
皮肤病学 | 25篇 |
神经病学 | 61篇 |
特种医学 | 47篇 |
外科学 | 304篇 |
综合类 | 14篇 |
预防医学 | 45篇 |
眼科学 | 105篇 |
药学 | 41篇 |
肿瘤学 | 21篇 |
出版年
2023年 | 8篇 |
2022年 | 17篇 |
2021年 | 38篇 |
2020年 | 28篇 |
2019年 | 31篇 |
2018年 | 42篇 |
2017年 | 30篇 |
2016年 | 39篇 |
2015年 | 61篇 |
2014年 | 55篇 |
2013年 | 69篇 |
2012年 | 90篇 |
2011年 | 79篇 |
2010年 | 46篇 |
2009年 | 40篇 |
2008年 | 80篇 |
2007年 | 80篇 |
2006年 | 94篇 |
2005年 | 73篇 |
2004年 | 65篇 |
2003年 | 48篇 |
2002年 | 53篇 |
2001年 | 34篇 |
2000年 | 34篇 |
1999年 | 31篇 |
1998年 | 13篇 |
1996年 | 5篇 |
1995年 | 8篇 |
1994年 | 6篇 |
1993年 | 5篇 |
1992年 | 24篇 |
1991年 | 29篇 |
1990年 | 21篇 |
1989年 | 24篇 |
1988年 | 13篇 |
1987年 | 14篇 |
1986年 | 16篇 |
1985年 | 11篇 |
1984年 | 11篇 |
1983年 | 5篇 |
1982年 | 6篇 |
1979年 | 17篇 |
1978年 | 11篇 |
1977年 | 6篇 |
1974年 | 6篇 |
1973年 | 7篇 |
1971年 | 6篇 |
1969年 | 7篇 |
1967年 | 8篇 |
1965年 | 5篇 |
排序方式: 共有1585条查询结果,搜索用时 62 毫秒
31.
Ismail Ustunel Nuray Acar Burcu Gemici Ozlem Ozbey Imren Edizer Hakan Soylu Filiz Tepekoy Vecihe Nimet Izgut-Uysal 《Acta histochemica》2014
Apelin has been identified as an endogenous ligand of the orphan G-protein-coupled apelin receptor (APJR). These receptors are widely expressed in the central nervous system and periphery and play a role in the regulation of fluid and glucose homeostasis, feeding behavior, vessel formation, cell proliferation and immunity. We aimed to investigate whether water immersion and restraint stress have effects on apelin and APJR expression and apoptosis in heart tissue of male Wistar rats. The cardiac tissues were obtained from control, water immersion and restraint stress (WIRS) and apelin antagonist (F13A) + WIRS groups of rats and embedded in paraffin wax. Immunohistochemical staining methods were used to localize apelin, APJR and TUNEL immunopositive cells. H-SCORE was used for semi-quantitative determinations. Apelin protein levels were determined by Western blot in the cardiac tissues and plasma corticosteroid levels were measured by enzyme immunoassay (EIA). Apelin immunolocalization was found especially in endothelial cells and mast cells and faintly in cardiomyocytes, APJR immunostaining was shown in endothelial cells and cardiomyocytes, and TUNEL reaction was observed in endothelial cells and in some fibroblasts. Apelin expression was significantly increased in the WIRS and F13A + WIRS groups compared to the control group. The APJR reaction was similar in all groups. The number of TUNEL-positive cells was significantly higher in the F13A + WIRS group than that of the control group. Our study showed that WIRS for 6 h increased plasma corticosterone levels and cardiac apelin expression in rats. The increased levels of apelin inhibited stress-induced apoptosis in heart. These results may be important for the therapeutic approach to a variety of stress-related heart disease. 相似文献
32.
The main purpose of this study was to investigate the relation between carotid intima-media thickness (CIMT) and coronary artery disease (CAD) complexity. Consecutive patients (n = 360) with CAD confirmed by coronary angiography were enrolled. Mean CIMT and the overall SYNTAX score (SXscore) were 0.87 ± 0.12 mm and 15 ± 9, respectively. In univariate analysis, there was a significant correlation between the overall SXscore and CIMT (r = .42, P < .001), age (r = .23, P < .001), hypertension (r = .27, P = 0.001), diabetes (r = 0.11, P = 0.02), smoking (r = .24, P = .01), dyslipidemia (r = .2, P = 0.03), and β-blocker use (r = .19, P < .001). In multivariate analysis, CIMT (β = .34, P < .001) and age (β = .11, P < .019) were independently associated with SXscore. We have demonstrated a significant relation between CIMT and SXscore. Although this study is correlative and no causative conclusions can be drawn, our findings suggest that increased CIMT could reflect complex coronary artery lesions. 相似文献
33.
34.
S. Said Kökçam Şakir Tekin Adil Kartal Murat Ayaz Mustafa Şahin Fahreddin Acar Murat Çakir Yusuf Küçükbağriaçik 《The Journal of surgical research》2013
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35.
36.
Ahmet Akcay Gurkan Acar Abdullah Sokmen Gulizar Sokmen Ekrem Dogan Hayriye Sayarlioglu 《Renal failure》2013,35(6):464-469
Background. Insulin resistance was an independent predictor of cardiovascular mortality in uremic patients without diabetes. Rosiglitazone (ROS) improves insulin sensitivity in the liver, muscle, and adipose tissue. We prospectively investigated the effects of ROS on cardiac functions by standard (SDE) and tissue Doppler echocardiography (TDI) in continuous ambulatory peritoneal dialysis (CAPD) patients. Methods. A total of 24 CAPD patients (13 males, 11 females; mean age 42.2 ± 14.8 years) were included. Routine blood samples were examined. Left and right ventricular functions were assessed, and myocardial performance index (MPI) was calculated by SDE and TDI at baseline and after 12-month ROS therapy. Left and right atrial volumes were measured and indexed to body surface area. Results. When compared with baseline, after 12 months of ROS treatment, it was shown that early (E) and late (A) diastolic velocities of atrioventricular valves, E/A ratio, mitral E-wave deceleration time (DT), isovolumetric relaxation time (IVRT), and MPI were similar (p > 0.05). Also, no significant changes were detected in LV dimensions, LV mass index, LVEF, LA volume index, or RA volume index measured by SDE before and after ROS therapy (p > 0.05). Left and right ventricular function parameters measured by TDI including Sm, Em, Am, Em/Am ratio, E/Em ratio, and MPI were similar. Conclusion. It was found that there was no negative effect of long-term ROS therapy on cardiac functions measured by SDE and TDI in CAPD patients. 相似文献
37.
38.
Objectives: This research aimed to evaluate pre-operatively and post-operatively the olfactory function of patients who had undergone surgery in our clinic for chronic nasal blockage via the Connecticut Chemosensory Clinical Research Center (CCCRC) smell test.Method: Thirty-seven patients (24 females, 13 males) were enrolled in this study. All had undergone surgery in our clinic due to chronic nasal blockage (not for smell dysfunction), having been diagnosed with septal deviation in conjunction with concha bullosa and/or inferior turbinate hypertrophy. This is a prospective study without a control group. The mean age was 33.74?±?8.98 (range =19–54). All of the operations were performed under general anesthesia. CCCRC smell tests were performed on every patient before the operation and at post-operative 1st week, 6th week, 6th month, and 1st year.Results: In this study, we found that septoplasty, in conjunction with middle concha surgery and/or inferior concha radiofrequency, did not affect the olfactory function negatively.Conclusion: Although nasal surgery has the potential to affect the smell function negatively, it was found that olfactory function was not affected after the surgery during a considerably long follow-up period. Moreover, an improvement in smell function was detected at post-operative 6th month and 1st year. 相似文献
39.
Acar Baver Kose Ozkan Unal Melih Turan Adil Kati Yusuf Alper Guler Ferhat 《European journal of orthopaedic surgery & traumatology : orthopedie traumatologie》2020,30(1):163-173
European Journal of Orthopaedic Surgery & Traumatology - This retrospective study aimed to compare the clinical and radiological outcomes of patients who underwent biplane chevron medial... 相似文献