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   8388篇
  免费   596篇
  国内免费   63篇
耳鼻咽喉   91篇
儿科学   253篇
妇产科学   236篇
基础医学   859篇
口腔科学   352篇
临床医学   803篇
内科学   1943篇
皮肤病学   295篇
神经病学   486篇
特种医学   349篇
外国民族医学   3篇
外科学   1338篇
综合类   245篇
现状与发展   30篇
一般理论   5篇
预防医学   527篇
眼科学   173篇
药学   524篇
中国医学   43篇
肿瘤学   492篇
  2024年   26篇
  2023年   277篇
  2022年   233篇
  2021年   409篇
  2020年   289篇
  2019年   330篇
  2018年   456篇
  2017年   262篇
  2016年   248篇
  2015年   307篇
  2014年   416篇
  2013年   445篇
  2012年   639篇
  2011年   603篇
  2010年   392篇
  2009年   338篇
  2008年   448篇
  2007年   384篇
  2006年   356篇
  2005年   346篇
  2004年   285篇
  2003年   245篇
  2002年   204篇
  2001年   73篇
  2000年   66篇
  1999年   70篇
  1998年   58篇
  1997年   69篇
  1996年   65篇
  1995年   52篇
  1994年   50篇
  1993年   47篇
  1992年   31篇
  1991年   52篇
  1990年   31篇
  1989年   54篇
  1988年   41篇
  1987年   43篇
  1986年   20篇
  1985年   30篇
  1984年   21篇
  1983年   15篇
  1982年   20篇
  1981年   20篇
  1980年   24篇
  1979年   16篇
  1978年   19篇
  1976年   17篇
  1975年   18篇
  1974年   19篇
排序方式: 共有9047条查询结果,搜索用时 15 毫秒
61.
62.
The aim of this study was to characterize timing, kinetic, and magnitude of CMV‐specific immune response after hematopoietic stem cell transplantation (HSCT) and its ability to predict CMV replication and clinical outcomes. Using cell surface and intracellular cytokine staining by flow cytometry, CMV‐specific T‐cell response was measured in blood, while CMV viral load and chimerism were determined by real‐time PCR. Patients that reconstituted CMV‐specific T‐cell response within 6 weeks after Allo‐SCT showed a more robust immune response (CD8+: 0.7 cells/μl vs. 0.3/μl; P‐value = 0.01), less incidence of CMV replication (33% vs. 89.5%; P‐value = 0.007), reduced viral loads (1.81 log copies/ml vs. 0 copies/ml; P‐value = 0.04), and better overall survival (72%; CI: 0.53–0.96 vs. 42% CI: 0.24–0.71; P‐value = 0.07) than patients with a delayed immune reconstitution. Viremic patients had significantly higher transplant‐related mortality than nonviremic patients after 1 year (33% CI: 0.15–0.52 vs. 0% CI: 0.05–0.34; P‐value = 0.01). Risk factors independently associated with viral replication were receptor pretransplant CMV‐positive serostatus (P‐value = 0.02) and acquiring CMV‐specific T‐cell response after 6 weeks post‐transplantation (P‐value = 0.009). In conclusion, timing of acquiring a positive CMV‐specific T‐cell immune response after transplantation may identify patients with different risk for viral replication and different clinical outcomes, including survival.  相似文献   
63.
Depression commonly overlaps with uremic symptoms, but anxiety is less commonly studied among renal patients. The symptoms of medical illness, along with the psychological and social stresses that often accompany a debilitating chronic disease, are thought to produce deleterious psychological consequences. We sought to determine the prevalence and predictors of anxiety and depression among Saudi dialysis patients in Makkah. A cross-sectional study of anxiety and depression among end-stage renal disease (ESRD) patients in Makkah was conducted in November 2011. The Hospital Anxiety and Depression Scale (HADS) was used to screen for anxiety and depression. Participants’ demographic data, possible stressors and past psychiatric history were obtained. All participants were Saudi ESRD patients on maintenance hemodialysis. According to HADS, 57 (21.1%) patients were probable cases of anxiety and 63 (23.3%) were probable cases of depression. Only 32 (11.3%) were diagnosed with depression or anxiety before ESRD onset. Age was a significant predictor of anxiety and depression diagnoses. Major family problems (p?=?0.001) were also a significant predictor of anxiety. Anxiety and depressive symptoms are prevalent among ESRD patients in Makkah, and anxiety can be predicted by family factors. Early detection, management and family support might improve clinical outcomes.  相似文献   
64.
The aim of the current study is to assess the impact of disease‐free interval (DFI) following treatment of primary localized breast cancer on the outcomes of patients with subsequent metastatic breast cancer treated with first‐line docetaxel chemotherapy. This study is a combined analysis of patient‐level raw data of 604 metastatic breast cancer patients referred for docetaxel first‐line chemotherapy in two clinical trials. Overall survival and time to progression were evaluated according to DFI through Kaplan‐Meier analysis. Multivariate analysis of factors affecting overall survival and time to progression was then conducted through Cox regression analysis. For the overall cohort, shorter DFI is associated with worse overall survival (P < 0.0001). When classified by the hormone receptor status, the shorter interval was associated with worse overall survival in both hormone receptor positive and negative patients (P = 0.009; P = 0.018; respectively). Likewise, shorter DFI is associated with shorter time to progression (P < 0.0001) in the overall cohort. When classified by the hormone receptor status, the shorter interval was associated with shorter time to progression for hormone receptor negative but not positive patients (P = 0.001; P = 0.070; respectively). In multivariate Cox regression analysis, the following factors were associated with worse overall survival: shorter DFI (P < 0.0001), poorer ECOG performance score (P = 0.008) and lower body mass index (P = 0.018). Likewise, in multivariate Cox regression analysis, the following factors were associated with shorter time to progression: shorter DFI (P < 0.0001) and hormone receptor negative status (P = 0.025). Shorter DFI was associated with worse overall survival and shorter time to progression among patients receiving first‐line docetaxel chemotherapy.  相似文献   
65.
We aimed to evaluate the use of diffusion‐weighted imaging (DWI) in the assessment of the varicocele effect on testicular parenchyma and spermatogenesis, with estimation of apparent diffusion coefficient (ADC) value changes in the testicular parenchyma. We prospectively evaluated 30 consecutive patients (18 patients with bilateral varicocele and 12 patients with unilateral varicocele) and 10 healthy controls. US and DWI were performed to all patients. A total of 80 testes were included, which divided into three groups: group A: testes ipsilateral to the varicocele (n = 48, 60%); group B: testes contralateral to the varicocele (n = 12, 15%); and group C: normal testes of the control (n = 20, 25%). There was a statistically significant difference in mean ADC value between all groups (p‐value < 0.001). In groups A and B, there was a negative correlation between mean ADC values and varicocele grade as well as pampiniformis venous diameter. In group A, there was a significant positive correlation between mean ADC value and sperm count (p‐value = 0.01, r‐value = 0.48) as well as sperm motility (p‐value = 0.04, r‐value = 0.33). DWI sequence can be used to evaluate the sequel of varicocele, with decreased ADC values that are significantly correlated with abnormal semen parameters. Thus, ADC values may be considered as an ancillary indicator of testicular parenchyma changes.  相似文献   
66.
Shah OJ  Dar MA  Wani NA  Robbani I  Zargar SA 《Digestive surgery》2004,21(2):108-13; discussion 113
BACKGROUND: Post-cholecystectomy syndrome encompasses numerous biliary, pancreatic and other entities. Biliary ascariasis is a common cause of adult biliary disease in an endemic area. Post-cholecystectomy biliary ascariasis, a cause of post- cholecystectomy syndrome although not yet defined is frequently seen in this part of the world. METHOD: Between Jan. 1990 and Jan. 2001, 104 cases of post-cholecystectomy biliary ascariasis were seen. Ultrasonography was found to be an excellent tool for diagnosing and monitoring of the worms inside the biliary tract. Endoscopic retrograde cholangiopancreatography had both diagnostic and therapeutic value. RESULTS: The majority (68.2%) of patients responded to conservative treatment. Surgical treatment was advocated in 18.2%, which included 2 patients with liver abscesses. Endoscopic extraction of worms was successful in 48.2%. CONCLUSION: Post-cholecystectomy biliary ascariasis as a cause of post-cholecystectomy syndrome needs to be included in the list of causes for post-cholecystectomy syndrome. Although the majority of patients respond to conservative treatment but endoscopic extraction or surgical intervention may be needed. Routine deworming of patients undergoing cholecystectomy both preoperatively and postoperatively should be done in all patients in endemic areas of ascariasis. Although this entity is rare in Europe and United States, due to population migration and increased travel, it is necessary for surgeons in these countries to be aware of this condition.  相似文献   
67.
68.
Disease status assessment of neuroblastoma patients requires computed tomography (or magnetic resonance imaging), bone scan, metaiodobenzylguanidine (MIBG) scan, bone marrow tests, and urine catecholamine measurements. There is no clinical experience concerning the evaluation of these patients by means of technetium-99m (99mTc)-somatostatin analog scintigraphy. Furthermore, these radiopharmaceuticals are promising imaging agents owing to their lower cost, availability, dosimetry, and ease of preparation. An 8-year-old boy already diagnosed with stage-IV neuroblastoma received chemotherapy. In the follow-up, after obtaining the parents’ informed consent, iodin 131 (131I)-MIBG and 99mTc-6-hydrazinopyridine-3-carboxylic acid (HYNIC)-octreotide scans were done on separate days to evaluate tumor extension. Even as the 131I-IBG scan showed mild diffuse uptake in the projection of both lung hili, the 99mTc-HYNIC-octreotide scan showed multiple axial and appendicular bone uptakes and paravertebral, abdominal, mediastinal, and supraclavicular ganglionar uptakes. The 99mTc-HYNIC-octreotide showed much more lesion extension than the 131I-MIBG. Therefore, 99mTc-HYNIC-octreotide may be a promising radiopharmaceutical for the evaluation of neuroblastoma patients. This finding justifies the pre liminary evaluation of this tracer in the context of a clinical trial.  相似文献   
69.

Background

There is a paucity of literature comparing laparoscopic to robotic inguinal hernia repair. We present a single surgeon’s transition from laparoscopic totally extraperitoneal (L-TEP) to robotic transabdominal preperitoneal (R-TAPP) inguinal hernia repair and compare outcomes from the two approaches.

Methods

This retrospective review and analysis of prospectively collected data compare outcomes during the transition from L-TEP to R-TAPP inguinal hernia repair by a single surgeon at one institution. Operating times and surgical outcomes and complications are analyzed. All consecutive L-TEP cases from November 2012 to August 2014 and all consecutive R-TAPP cases from March 2013 to October 2015 were included in the analysis.

Results

A total of 157 and 118 patients underwent L-TEP and R-TAPP inguinal hernia repair, respectively. The groups were similar regarding demographics and ASA class. A significantly higher number of complex cases were performed in the R-TAPP group compared to L-TEP group (n = 11 vs. n = 1, p = 0.0001). Mean surgical times were nearly identical (69.12 ± 35.13 min, R-TAPP; 69.05 ± 26.31, L-TEP) as were intraoperative and postoperative complication rates—despite the significantly higher number of complex cases in the R-TAPP group.

Conclusions

This is the largest study in the literature comparing a single surgeon’s experience transitioning from L-TEP to R-TAPP inguinal hernia repair. Results from the R-TAPP cases were similar to those achieved from laparoscopic cases. The robotic platform may have facilitated the execution of complex hernia cases during the proficiency phase.
  相似文献   
70.
The Peritraumatic Distress Inventory (PDI) is a well-known self-report questionnaire indexing the distress experienced during and shortly after a most stressful or traumatic event. Although sociodemographic factors contributing to peritraumatic distress have been previously investigated, no research has examined the nature and severity of peritraumatic distress reactions in a non-clinical, community sample as a function of age. An international sample of 5621 adult participants were grouped according the World Health Organization's age stratification protocol. Mean scores and item endorsement on the PDI were compared across groups with respect to their worst experience of the COVID-19 pandemic. A significant between-group difference was found, F(55,615) = 30.74, p < 0.001, n2 = 0.027 whereby participants aged 18–39 years old reported the highest levels of peritraumatic distress. This group also endorsed a higher proportion of items on the PDI's two main factors (emotional distress and physical reactions), and were more likely to endorse feelings of helplessness, than older participants. It appears that severity of peritraumatic distress during the pandemic has affected younger people the most. Results are discussed in light of clinical implications.  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