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   1381篇
  免费   69篇
  国内免费   5篇
耳鼻咽喉   29篇
儿科学   99篇
妇产科学   93篇
基础医学   117篇
口腔科学   59篇
临床医学   133篇
内科学   325篇
皮肤病学   55篇
神经病学   90篇
特种医学   61篇
外科学   240篇
综合类   20篇
预防医学   31篇
眼科学   22篇
药学   50篇
中国医学   1篇
肿瘤学   30篇
  2023年   10篇
  2022年   24篇
  2021年   48篇
  2020年   30篇
  2019年   37篇
  2018年   37篇
  2017年   39篇
  2016年   53篇
  2015年   55篇
  2014年   46篇
  2013年   57篇
  2012年   112篇
  2011年   100篇
  2010年   66篇
  2009年   65篇
  2008年   100篇
  2007年   102篇
  2006年   72篇
  2005年   93篇
  2004年   68篇
  2003年   64篇
  2002年   56篇
  2001年   23篇
  2000年   15篇
  1999年   12篇
  1998年   9篇
  1997年   8篇
  1996年   4篇
  1995年   3篇
  1994年   1篇
  1993年   2篇
  1992年   9篇
  1991年   5篇
  1990年   3篇
  1989年   3篇
  1988年   2篇
  1987年   3篇
  1986年   1篇
  1984年   5篇
  1983年   2篇
  1981年   1篇
  1980年   1篇
  1979年   2篇
  1978年   1篇
  1975年   2篇
  1974年   1篇
  1972年   2篇
  1970年   1篇
排序方式: 共有1455条查询结果,搜索用时 15 毫秒
31.
Discoid lupus erythematosus (DLE) is a chronic inflammatory erythematous skin disease that can be triggered by several factors. Rosacea is another skin disease that causes facial redness and tenderness. Demodex mites have been reported in rosacea and DLE patients commonly in the literature. These two diseases can be seen concomitant, mimic each other clinically and share common possible etiologic factors. To assess demodex mite infestation in both clinical and histopathological findings in DLE patients. We retrospectively evaluated the files of 42 patients with DLE who had been diagnosed DLE based on clinical and histopathological findings between August 2018 and August 2019. Demodex positivity was detected 50% of patients (n = 21). Neutrophile percentages in the dermal and perivascular area were higher in the demodex positive patients (4.43%) than in the Demodex negative patients (2.19%). The intensity of demodex mites correlated positively with dermal neutrophile percentages. ANA was negative in 29 patients (69%) and positive in 13 patients (31%). Anti‐dsDNA was negative in serology and follicular plugging was positive in histopathology in all 42 patients (100%). This was a retrospective study. DLE and rosacea share common features in etiopathogenesis and clinical presentation. Inflammation and exacerbations caused by the demodex mites may increase the clinical severity of DLE. Although the position of demodex mites in DLE etiopathogenesis is not known exactly, the presence of high demodex in DLE patients has been determined. Standard skin surface biopsy can be a routine procedure for the evaluation of DLE patients in daily clinical practice.  相似文献   
32.
A new type of coronavirus family (SARS‐CoV‐2), which can be found in humans and animals, with many varieties and clinical symptoms, was first seen in Wuhan, China in late 2019, under the name novel Coronavirus Disease 2019 (COVID‐19). In the literature, cutaneous symptoms related to the disease are generally emphasized. However, it is not yet known whether this new SARS‐CoV‐2 virus, which has entered our lives, plays a role in the etiopathogenesis of dermatological diseases. The patients who were admitted to the dermatology outpatient clinic between 1 April and 15 May 2019, and on 1 April and 15 May 2020 were retrospectively analyzed by searching the hospital automation system and patient files. The reason for the same months to be included in the study was to exclude seasonal effects on the diseases. After pandemic, the number of patients with Pityriasis rosea and Kawasaki disease increased significantly in patients who applied to the dermatology outpatient clinic. Our study is the first study showing Pityriasis rosea increase during the pandemic period. We think that this increase is related to HHV‐6 reactivation. Herein, we wanted to draw attention to two diseases in which Human Herpes 6 (HHV‐6) was accused in etiopathogenesis: Kawasaki disease and Pityriasis rosea.  相似文献   
33.
Although there are alternative methods and drugs for preventing venous thromboembolism (VTE), it is not clear which modality is most suitable and efficacious for patients with severe (stable or unstable) head/spinal injures. The aim of this study was to compare intermittent pneumatic compression devices (IPC) with low-molecular-weight heparin (LMWH) for preventing VTE. We prospectively randomized 120 head/spinal traumatized patients for comparison of IPC with LMWH as a prophylaxis modality against VTE. Venous duplex color-flow Doppler sonography of the lower extremities was performed each week of hospitalization and 1 week after discharge. When there was a suspicion of pulmonary embolism (PE), patients were evaluated with spiral computed tomography. Patients were analyzed for demographic features, injury severity scores, associated injuries, type of head/spinal trauma, complications, transfusion, and incidence of deep venous thrombosis (DVT) and PE. Two patients (3.33%) from the IPC group and 4 patients (6.66%) from the LMWH group died, with their deaths due to PE. Nine other patients also succumbed, unrelated to PE. DVT developed in 4 patients (6.66%) in the IPC group and in 3 patients (5%) in the LMWH group. There was no statistically significant difference regarding a reduction in DVT, PE, or mortality between groups (p = 0.04, p > 0.05, p > 0.05, respectively). IPC can be used safely for prophylaxis of VTE in head/spinal trauma patients.  相似文献   
34.
AIMS: This study was undertaken to compare periodontal conditions, gingival crevicular fluid (GCF) levels of tissue-type plasminogen activator (t-PA), its inhibitor plasminogen activator inhibitor-2 (PAI-2), interleukin-1beta (IL-1beta), prostaglandin E(2) (PGE(2)) in rheumatoid arthritis (RA) patients and control groups. METHODS: Twenty-three RA patients, 17 systemically healthy patients with periodontal disease (PD), and 17 systemically and periodontally healthy subjects were recruited. GCF samples were obtained from two single-rooted teeth. Full-mouth clinical periodontal measurements were recorded at six sites/tooth. GCF samples were analysed using relevant ELISA kits. Data were tested statistically by appropriate tests. RESULTS: Total amounts of t-PA, PAI-2 and PGE(2) in GCF samples of the healthy control group were significantly lower than the other groups (p<0.05). The RA group exhibited a higher total amount of t-PA in GCF samples than the PD group (p<0.05). PAI-2, IL-1beta and PGE(2) total amounts were similar in RA and PD groups (p>0.05). CONCLUSION: The coexistence of RA and periodontitis does not seem to affect clinical periodontal findings or systemic markers of RA. Similar inflammatory mediator levels in RA and PD groups, despite the long-term usage of corticosteroids, non-steroidal anti-inflammatory drugs, suggest that RA patients may have a propensity to overproduce these inflammatory mediators.  相似文献   
35.

Background

This study was performed to evaluate gingival crevicular fluid (GCF) and serum levels of a proliferation inducing ligand (APRIL) and B cell activating factor (BAFF) and compare this to differences between TNF-alpha levels in rheumatoid arthritis (RA), osteoporosis (OPR) and systemically healthy women with periodontal disease (SH).

Design

Gingival crevicular fluid (GCF) and serum samples were obtained before any periodontal intervention from 17 RA, 19 OPR patients and 13 SH women with periodontitis. Full-mouth clinical periodontal measurements were recorded. APRIL, BAFF and TNF-α levels were determined by ELISA. Statistical analysis was performed using multivariate analysis, ANOVA and Spearman correlation.

Results

Pocket depths differed in site-specific comparisons, but otherwise clinical measurements were similar in the three study groups. Multivariate least squares regression ANOVA adjusted for age and for plaque index indicated that total amounts of TNF-α and concentrations of TNF-α, BAFF and APRIL were significantly greater in the RA patients than in the SH group (p < 0.05), and GCF concentrations of BAFF were greater in OPR patients than in SH. Serum TNF-α and BAFF were significantly higher in the RA group compared to SH (p < 0.05) and serum TNF-α was greater in RA than in OPR (p < 0.05). APRIL and BAFF correlated with RANKL levels in GCF and serum (p < 0.05).

Conclusion

Despite long-term usage of anti-inflammatory drugs in the RA and OPR patients, increased TNF-family cytokines, might suggest that these patients have a propensity to overproduce these inflammatory mediators but whether this results from greater disease activity or contribute to greater disease activity remains moot.  相似文献   
36.
37.
38.
BACKGROUND AND PURPOSE: Several methods of assessing disease severity in restless legs syndrome (RLS) have been suggested. The purpose of this study was to examine the relationship between the suggested immobilization test (SIT), the International RLS Study Group rating scale (IRLS), sleep efficiency, and periodic leg movements of sleep index (PLMI). PATIENTS AND METHODS: Forty primary RLS patients with periodic leg movements of sleep were included in this prospective study. Study procedures were all performed during the same night, beginning with IRLS administration and following with SIT and polysomnography (PSG) evaluations, in that order. SIT was composed of two parameters: SIT mean discomfort score (SIT-MDS) and SIT periodic leg movements of wakefulness index (SIT-PLMW). PSG target measures were PLMI and sleep efficiency. Pearson's correlation was used for analysis at a P<0.01 significance level. RESULTS: PSG-PLMI correlated with IRLS (r=0.462; P=0.003) and with SIT-PLMW (r=0.681; P=0.0004). A correlation was also found between IRLS and SIT-MDS (r=0.447; P=0.004), even though SIT-PLMW and IRLS did not correlate with each other (P=0.286). A negative correlation was found between PSG-PLMI and sleep efficiency (r=-0.435; P=0.005). Neither SIT nor IRLS correlated with sleep efficiency. Only SIT discomfort scores from the second half of SIT correlated with SIT-PLMW (r=0.457, P=0.004), and they had a stronger correlation with IRLS (P=0.003). CONCLUSIONS: This study attempted a much needed comprehensive evaluation of the relationship between various RLS severity indicators. Our findings support a strong role of motor dysfunction on sleep quality in RLS, as well as the potential use of SIT-PLMW as a sensitive indicator of RLS severity.  相似文献   
39.
INTRODUCTION: Thrombin activatable fibrinolysis inhibitor (TAFI) is a procarboxypeptidase downregulating plasmin formation, thereby causing a tendency for thrombosis development. Since, Beh?et's disease (BD) is a systemic vasculitis, which is commonly complicated by arterial and venous thrombosis, we aimed to find out plasma TAFI levels in BD, compared with healthy controls. We also searched whether plasma TAFI levels were significantly different between Beh?et's subgroups with and without thrombosis. MATERIALS AND METHODS: In this study, 105 BD patients (M/F: 64/41; mean age 36+/-1 years), followed up by Ege University Rheumatology Department were enrolled. The exclusion criteria were hemophilia, hyperlipidemia, diabetes mellitus, hepatic diseases renal failure, antiphospholipid positivity, oral contraceptive use and pregnancy. Age-and sex-matched healthy controls (n=53) were also included. Plasma TAFI levels were measured by ELISA. Since TAFI is also an acute-phase reactant, we also measured other inflammatory markers such as C-reactive protein (CRP). RESULTS: Plasma TAFI levels were significantly higher in Beh?et's patients (91.1+/-7.4 ng/ml) compared with healthy controls (14.3+/-4.5 ng/ml) (P<0.001), but there were no significant difference between the subgroups with and without thrombosis. In BD, there was no correlation between plasma TAFI levels and CRP. CONCLUSIONS: Regardless of manifest thrombosis, plasma TAFI levels in BD were significantly higher than in healthy controls. High TAFI levels might possibly contribute to the thrombotic tendency in BD. Future studies investigating TAFI gene polymorphism and functional activity are clearly needed, to clarify the exact role of TAFI in Beh?et's thrombosis.  相似文献   
40.

Objective

To investigate the plasma levels of activated thrombin activatable fibrinolysis inhibitor (aTAFI) and thrombomodulin (TM) in Behçet disease (BD) and their relationship with thrombosis.

Methods

Plasma aTAFI and TM levels were measured by ELISA in 89 patients with BD (18 having venous thrombosis) and in 86 healthy controls.

Results

Compared with healthy controls, the BD group had significantly lower levels of aTAFI (13.49 ± 8.88 µg/ml vs. 26.76 ± 11.57 µg/ml, p < 0.0001) and significantly higher levels of TM (3.26 ± 1.85 ng/ml vs. 2.6 ± 0.69 ng/ml, p = 0.0003). Neither aTAFI, nor TM levels differed significantly between BD patients with and without thrombosis (p > 0.05). Despite a tendency to positive correlation (r = 0.37, p = 0.0004) between plasma levels of aTAFI and TM in healthy controls, there was a tendency for negative correlation (r = -0.51, p < 0.0001) between these two parameters in BD patients.

Conclusion

The plasma aTAFI and TM levels do not seem to be related with the presence of thrombosis observed in BD. Increased plasma TM levels in BD may simply reflect endothelial cell activation and dysfunction.  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