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   1228篇
  免费   61篇
  国内免费   1篇
耳鼻咽喉   50篇
儿科学   102篇
妇产科学   42篇
基础医学   99篇
口腔科学   42篇
临床医学   119篇
内科学   330篇
皮肤病学   36篇
神经病学   51篇
特种医学   35篇
外科学   179篇
综合类   15篇
预防医学   37篇
眼科学   16篇
药学   106篇
中国医学   4篇
肿瘤学   27篇
  2023年   8篇
  2022年   14篇
  2021年   13篇
  2020年   20篇
  2019年   28篇
  2018年   30篇
  2017年   21篇
  2016年   48篇
  2015年   36篇
  2014年   50篇
  2013年   63篇
  2012年   92篇
  2011年   92篇
  2010年   44篇
  2009年   43篇
  2008年   88篇
  2007年   106篇
  2006年   102篇
  2005年   103篇
  2004年   62篇
  2003年   43篇
  2002年   47篇
  2001年   25篇
  2000年   15篇
  1999年   10篇
  1997年   6篇
  1996年   2篇
  1995年   4篇
  1992年   7篇
  1991年   6篇
  1990年   7篇
  1989年   4篇
  1988年   8篇
  1987年   5篇
  1986年   5篇
  1985年   7篇
  1984年   2篇
  1983年   1篇
  1982年   3篇
  1980年   1篇
  1979年   2篇
  1978年   3篇
  1977年   1篇
  1976年   1篇
  1975年   2篇
  1974年   2篇
  1973年   2篇
  1972年   2篇
  1971年   1篇
  1970年   2篇
排序方式: 共有1290条查询结果,搜索用时 312 毫秒
31.
Angiographic prevalence of myocardial bridging.   总被引:2,自引:0,他引:2  
OBJECTIVE: Muscle fibers overlying the intramyocardial segment of an epicardial coronary artery are termed myocardial bridging. Variable prevalence has been described at autopsy and angiographic series with small and large sample sizes. The aim of the study was to investigate the angiographic prevalence of myocardial bridging in 25982 patients from Turkey. METHODS: We performed a retrospective study, evaluated the cases with myocardial bridging among patients undergone selective coronary angiography, and searched the angiographic prevalence of myocardial bridging in a very large sample size. We studied also the correlation between the severity of the bridging and risk factors for coronary artery disease. RESULTS: Among 25982 patients we found 316 cases of myocardial bridging in a retrospective manner. The total prevalence was 1.22%. Although, 96.52% of patients with myocardial bridging had the lesion in the left anterior descending coronary artery (LAD) as expected, distribution of bridges between mid- and distal segments were almost equal (52.79% and 47.21%, respectively). We subclassified patients in two groups, Group A (<50% of systolic compression) and Group B (>or=50% of systolic compression), according to the amount of systolic compression of LAD and studied relationship of risk factors for coronary artery disease between groups. Another subclassification was also made for patients having myocardial bridging without coronary or valvular heart disease and hypertrophic obstructive cardiomyopathy; Group 1 (<50% of systolic compression) and Group 2 (>or=50% of systolic compression). In these patients we studied correlation between the severity of the myocardial bridging and risk factors for coronary artery disease. The prevalence of bridges in circumflex and right coronary arteries individually and in all arteries as combination was also studied. CONCLUSION: In a very large group of patients from Turkey undergone selective coronary artery angiography, the angiographic prevalence of myocardial bridging was slightly higher than expected. Only diabetes mellitus as a risk factor for coronary artery disease was higher in groups representing <50% of systolic compression (Group A and 1) than in groups representing >or=50% of systolic compression (Group B and 2) but the importance of this result is not known.  相似文献   
32.
33.
Functional limitations for the vitamin K cycle, caused either by mutations in gamma-glutamyl carboxylase or vitamin K epoxide reductase genes, result in hereditary deficiency of vitamin K-dependent coagulation factors (VKCFD1 and VKCFD2, respectively). Patients suffering from VKCFD often share several other anatomical irregularities which are not related to haemostasis. Here we report on nine patients, eight of them previously unreported, who presented with VKCFD1. All were examined with special attention to vitamin K-dependent coagulation factors as well as to bone and heart development and to other anatomical signs of embryonal vitamin K deficiency. In total, we detected ten mutations in the gamma-glutamyl carboxylase gene of which seven have not been previously reported. Most interestingly, additional non-bleeding phenotypes were observed in all patients including midfacial hypoplasia, premature osteoporosis, cochlear hearing loss, heart valve defects, pulmonary stenosis, or pseudoxanthoma elasticum-like phenotype. Undercarboxylated matrix Gla protein, osteocalcin, and periostin appear to be responsible for these defects which are also observed in cases of fetal warfarin syndrome.  相似文献   
34.
Carpal tunnel syndrome (CTS) is one of the most frequent extra-articular manifestations of rheumatoid arthritis (RA). High frequency ultrasonography (US) is a sensitive and specific method in diagnosis of CTS. This study is aimed to: firstly assess diameter frequency of CTS in RA with US and compare with a control group; secondly, investigate relationship of CTS with disease activity. One hundred consecutive RA patients (women/men: 78/22) fulfilling ACR 1987 RA criteria and 45 healthy controls (women/control: 34/11) were enrolled into study. Disease activity parameters, RA and CTS patient global assessment and health assessment questionnaire (HAQ-DI) were recorded. Both patient and control group were questioned about secondary causes of CTS, and Katz hand diagram, Boston CTS questionnaire and Phalen ve Tinel tests were applied once for each hand. Wrist joint and carpal tunnel were assessed with US grey scale and power Doppler US, then cross-sectional area of median nerve (CSA) was calculated. Patients with median nerve CSA between 10.0 and 13.0 mm(2) were evaluated with electromyography (EMG). CTS was diagnosed if CSA of median nerve >13.0 mm(2) or CTS was shown with NCS. Although there was no difference between RA patients and controls in age, sex, history of DM (+) and goitre, CTS was more frequent in RA group (respectively, 17.0% vs. 4.4%, P = 0.038). In RA group with CTS, age, history of DM, disease duration, HAQ-DI score, CTS patient global score, Boston symptom severity and functional status scores were elevated compared to without CTS [respectively, 57 (36-73) vs. 50 (24-76), P = 0.041; 35.3% vs. 6.0%, P < 0.001; 108 (12-396) months vs. 72 (6-360) months, P = 0.036; 1.93 (0.75-2.87) vs. 1.125 (0-2.75), P = 0.013; 52 (1-97) vs. 25 (0-91), P = 0.001; 2.81 (1.18-4.17) vs. 2.0 (1.0-4.01), P = 0.01; 3.37 (1.37-5.0) vs. 2.25 (1.0-5.0), P = 0.008]. No difference was found between CTS (+) and (-) RA patients in acute phase reactants, disease activity and US findings (P > 0.05). Sensitivity of Katz hand diagram was higher than Tinel and Phalen tests (respectively, 100, 60.0, 66.7%). Boston symptom and functional scores of RA patients with CTS diagnosed by EMG were increased than patients CTS (-) by EMG [respectively, 3.05 (1.90-4.27) vs. 1.55 (1.0-2.90), P = 0.002; 3.25 (1.73-3.82) vs. 1.12 (1.0-2.10), P = 0.008]. CTS frequency in RA was found higher than normal population, especially in patients with additional risk factors of CTS. There was no relationship between CTS and disease activity. CTS group had long disease duration and worse functional status. CTS could be a result of the chronic course in RA. In patient with CSA between 10 and 13 mm(2), Boston CTS questionnaire might give additional idea about CTS.  相似文献   
35.

Background  

Cancer cachexia is a devastating condition leading to loss of function and independence, decreased performance status, decreased quality of life, and poor prognosis. Adipokines play a role in a wide variety of physiological or pathological processes, including immunity and inflammation, in addition to having significant effects on metabolism and lipogenesis. The objective of the present study was to investigate the relationship of adipokines and systemic inflammation in weight-losing advanced-stage non-small-cell lung cancer (NSCLC) patients.  相似文献   
36.
The home-based exercise therapy recommended to the patients with ankylosing spondylitis (AS) is a simply applicable and cheap method. The aim of this study was to investigate the effects of home-based exercise therapy on pain, mobility, function, disease activity, quality of life, and respiratory functions in patients with AS. Eighty patients diagnosed with AS according to the modified New York criteria were included in the study. Home-based exercise program including range of motion, stretching, strengthening, posture, and respiratory exercises was practically demonstrated by a physiotherapist. A training and exercise manual booklet was given to all patients. Patients following home-based exercise program five times a week at least 30 min per session (exercise group) for 3 months were compared with those exercising less than five times a week (control group). Visual analog scale pain (VASp) values at baseline were significantly higher in the exercise group. The exercise group showed improvements in VASp, tragus–wall distance, morning stiffness, finger–floor distance, modified Schober's test, chest expansion, the Bath Ankylosing Spondylitis Disease Activity Index, the Bath Ankylosing Spondylitis Functional Index, Ankylosing Spondylitis Quality of Life Questionnaire (ASQoL), forced expiratory volume in first second, and forced vital capacity at third month. There was significant difference in ASQoL scores between the two groups in favor of the exercise group at third month. Regular home-based exercise therapy should be a part of main therapy in patients with AS. Physicians should recommend that patients with AS do exercise at least five times a week at least 30 min per session.  相似文献   
37.
Abstract Objective. Isolated systolic hypertension (ISH) is generally encountered in elderly patients and there are scarce data regarding the renin-angiotensin-aldosterone system (RAAS) activity in patients with ISH. We aimed to determine the plasma renin activity (PRA), plasma aldosterone levels (PAL) and aldosterone/PRA ratio (PAL/PRA) in patients (age >50 years) with ISH and to compare these values with patients with essential hypertension (EH) as well as subjects with normal blood pressure values (control) who have similar age and cardiovascular risk profile. Methods. Consecutively, 42 untreated ISH patients, 30 patients with EH and 29 normal subjects were included in the study. Parameters were presented as median (interquartile range). Results. There were no significant differences regarding age, gender and other cardiovascular risk factors among groups. As expected, systolic, diastolic blood pressure and pulse pressure values were significantly different among groups. Besides, PRA values were found to be significantly lower in patients with ISH (0.4 [0.2-1.1] ng/ml/h) compared with the EH (0.95 [0.5-2.6] ng/ml/h, p =0.024) and control (1.3 [0.7-2.1] ng/ml/h, p =0.001) groups. Although, PAL were similar among groups, PAL/PRA ratio was significantly higher in ISH group (134.1 [73-224]) compared with those with EH (42.2 [35-84], p <0.001) and the control group (53.3 [30-106], p =0.001). No significant difference was present with respect to PAL/PRA ratio between EH and control groups. Conclusions. Our findings suggested that in patients with ISH, despite lower PRA levels, PAL/PRA ratio is significantly higher compared with the patients with EH and subjects with normal blood pressure. Since higher PAL/PRA levels is an indicator of relative aldosterone excess, medications blocking RAAS activity including aldosterone antagonists may have useful cardiovascular consequences in addition to their antihypertensive effects in ISH.  相似文献   
38.
Sule S  Fivush B  Neu A  Furth S 《Lupus》2012,21(11):1208-1213
Background: Systemic lupus erythematosus (SLE) is an autoimmune disease that can affect almost any organ system, including the kidneys. Using a large national dataset, our goal was to compare the morbidity as measured by hospitalization and mortality rates between hemodialysis patients with end-stage renal disease (ESRD) secondary to SLE to those with ESRD due to other causes. Methods: The risk of hospitalization was calculated by Poisson regression with clustering for repeated measures using the United States Renal Data System (USRDS) Hospitalization Analytic File in strata of pediatric and adult patients. Cox proportional hazard ratio was used to assess the mortality risk in hospitalized patients. Subjects were censored at transplantation or end of follow-up. Results: Adult patients with ESRD secondary to SLE were hospitalized more frequently than other adults (incidence rate ratio (IRR): 1.43, 95% confidence interval (CI): 1.15-1.77) and had a higher risk of death (hazard ratio (HR): 1.89, 95% CI: 1.66-2.5). Mortality was higher in hospitalized pediatric patients with SLE compared to pediatric patients with other causes of ESRD (HR: 2.01, 95% CI: 1.75-2.31) and adults with SLE (HR: 2.05, 95% CI: 1.79-2.34). Conclusion: Our study demonstrates that there is a trend toward increased hospitalization rates in pediatric and adult patients with SLE. Among these hospitalized patients with SLE, there is an increased risk of death due to cardiovascular disease.  相似文献   
39.
Cardiovascular problems are a major cause of morbidity and mortality in patients with autosomal dominant polycystic kidney disease (ADPKD). Endothelial dysfunction (ED), which is an early manifestation of vascular injury, has been shown in patients with ADPKD. Statins have a beneficial effect in the reversal of ED. The aim of this study was to investigate the effects of a statin, simvastatin, on ED in patients with ADPKD. Sixteen patients with ADPKD having well-preserved renal function were included in the study. Endothelial function of the brachial artery was evaluated by using high-resolution vascular ultrasound. Endothelial-dependent dilatation (EDD) was expressed as the percentage change in the brachial artery diameter from baseline to reactive hyperemia. After the baseline evaluations of EDDs, patients were started treatment with simvastatin at a dose of 40 mg/day and were treated for six months. EDDs were recalculated after one and six months of therapy. Interleukin-6 (IL-6) and high-sensitivity C-reactive protein were also measured as markers of inflammation. Baseline EDD was 11.3 ± 6.9% in patients with ADPKD. After one month of simvastatin treatment, EDD increased significantly to 14.6 ± 4.6 % (P = 0.016 versus baseline). Endothelial-dependent dilatation further increased significantly to 18.9 ± 7.5 % (P = 0.011 versus baseline, P = 0.048 versus first month) after six months of therapy. There was also a significant decrease in the level of IL-6 from 21.6 ± 21.7 pg/mL to 9.1 ± 3.5 pg/mL (P= 0.002).

Six months of simvastatin therapy resulted in a significant improvement of ED in patients with ADPKD. This finding may be in part related to the pleiotropic effects of simvastatin.  相似文献   
40.
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