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   59821篇
  免费   4943篇
  国内免费   2908篇
耳鼻咽喉   522篇
儿科学   754篇
妇产科学   748篇
基础医学   8374篇
口腔科学   981篇
临床医学   6996篇
内科学   9685篇
皮肤病学   1045篇
神经病学   3948篇
特种医学   2511篇
外国民族医学   26篇
外科学   6460篇
综合类   6601篇
现状与发展   12篇
一般理论   10篇
预防医学   3818篇
眼科学   1502篇
药学   6179篇
  38篇
中国医学   2470篇
肿瘤学   4992篇
  2024年   166篇
  2023年   906篇
  2022年   2242篇
  2021年   3007篇
  2020年   1965篇
  2019年   1902篇
  2018年   2069篇
  2017年   1777篇
  2016年   1912篇
  2015年   2766篇
  2014年   3305篇
  2013年   3343篇
  2012年   4792篇
  2011年   5081篇
  2010年   2956篇
  2009年   2401篇
  2008年   3355篇
  2007年   3149篇
  2006年   2963篇
  2005年   2859篇
  2004年   2135篇
  2003年   1777篇
  2002年   1570篇
  2001年   1260篇
  2000年   1335篇
  1999年   1277篇
  1998年   677篇
  1997年   622篇
  1996年   475篇
  1995年   432篇
  1994年   335篇
  1993年   259篇
  1992年   386篇
  1991年   349篇
  1990年   293篇
  1989年   259篇
  1988年   220篇
  1987年   202篇
  1986年   181篇
  1985年   146篇
  1984年   79篇
  1983年   70篇
  1982年   49篇
  1981年   39篇
  1980年   36篇
  1979年   49篇
  1978年   30篇
  1977年   22篇
  1974年   26篇
  1971年   21篇
排序方式: 共有10000条查询结果,搜索用时 22 毫秒
31.
男性慢性胃炎患者人格特征初探   总被引:4,自引:0,他引:4  
本文采用卡氏十六种人格因素量表,对纤维胃十二肠镜和活体组织病理检查确诊,剔除可能影响调查的疾患之后的56例慢性胃炎患者做了测查,结果与中国男性成人常模对照,提示男性慢性胃炎患者的主要人格特征有:严谨、保守、忧郁、紧张、顺从、依赖、有焦虑倾向,非内向个性,不属于心理不健康人群,而与消化性溃疡个性特征有所不同,但是,矫治其人格缺损及属必要。  相似文献   
32.
论医学生和谐就业伦理观的培养   总被引:3,自引:3,他引:0  
结合目前医学生在就业过程中出现的不和谐伦理现象,分析了其主客观原因,提出了医学生和谐就业伦理观培养的现实途径.  相似文献   
33.
BACKGROUND/PURPOSE: Bartonella henselaeis the causative agent of cat scratch disease (CSD), manifesting as fever and acute regional lymphadenopathy. Although serologic testing is the reference method for diagnosis, successful use of immunohistochemical (IHC) stain of regional lymph nodes for the diagnosis of CSD has been reported. To determine the characterization and diagnostic potential of IHC in lymphadenopathy of CSD, lymph nodes were excised from patients with suspected CSD for further evaluation. METHODS: Polyclonal antibody-based IHC studies were performed for the detection of B. henselae. Between January 2001 and December 2004, the reference laboratory of the Center for Disease Control, Taiwan, received a total of 377 sera from 352 reported suspected CSD cases. Twenty-three formalin-fixed paraffin-embedded lymph nodes from 16 patients and two skin biopsies from two patients suspected of having CSD were included in this study. Nine of them were serologically confirmed to have CSD and the others were seronegative but suspected to have CSD by the attending physicians. Seven lymph node specimens were obtained from tuberculosis patients for comparison. RESULTS: We demonstrated that the microorganisms existed in the cytoplasm of histiocytes within the granulomatous lesions in nine lymph nodes and one skin biopsy. Among the nine lymph nodes with IHC (+) stains, three were seronegative. On the other hand, three cases were IHC (+) and six cases were IHC (-) among nine seronegative patients. In addition, two seronegative patients with skin biopsy showed one IHC (+) and one IHC (-). CONCLUSION: IHC can contribute to the etiologic diagnosis of B. henselaelymphadenopathy when serology and molecular techniques are not available.  相似文献   
34.
BACKGROUND CONTEXT: Posterior lumbar interbody fusion (PLIF) is a popular method of arthrodesis for surgical treatment of instabilities and degenerative conditions of the spine. With the introduction of threaded titanium cage devices, surgeons began performing PLIF procedures using these cages as stand-alone devices. Complications have been reported, however, including pseudarthrosis with persistent pain. Outcomes after revision surgical treatment for these patients with failed PLIF are not known. PURPOSE: To prospectively evaluate clinical outcomes of revision fusion surgery in patients who previously underwent posterior lumbar interbody fusion with stand-alone metallic cages resulting in pseudarthrosis. STUDY DESIGN/SETTING: Prospective case series. METHODS: Nineteen patients referred to the senior author were evaluated and diagnosed with pseudoarthrosis having previously undergone a PLIF procedure with stand-alone metallic cages. History, physical exam, and imaging studies were performed preoperatively and postoperatively. All underwent revision posterolateral fusion with iliac crest graft and pedicle screw instrumentation. Patient demographics, SF-36, and Oswestry Disability Index (ODI) data were collected prior to surgery and two years postoperatively. RESULTS: Patients undergoing revision fusion surgery were found to have had extensive facetectomies and pseudarthrosis intraoperatively. Outcomes data was collected on eighteen of nineteen patients (95%). Mean clinical follow up was 3.2 years (range 2.5-3.5 years). Seventeen patients (94%) achieved a solid fusion. Improvement was noted in seven of eight SF-36 sub-categories, but was significant only in two (Physical Function and Role Emotional). There was no significant difference in ODI scores. CONCLUSIONS: Pseudarthrosis should be considered in the differential diagnosis if severe symptoms persist in patients who undergo PLIF with stand-alone metallic cages. Successful revision fusion did not always correlate with improved clinical outcomes in these challenging patients undergoing further surgery. Performing PLIF using stand-alone metallic cages, especially after total resection of the facet joints, is not advocated unless supplemental instrumentation is utilized.  相似文献   
35.
Background: Despite the fact that obesity is a known risk factor for cardiovascular disease, many studies have failed to demonstrate that obesity is independently associated with an increased risk of cardiovascular morbidity and mortality in nondiabetic patients undergoing coronary artery bypass graft surgery. The authors investigated the influence of obesity on adverse postoperative outcomes in diabetic and nondiabetic patients after primary coronary artery bypass surgery.

Methods: A retrospective cohort study of patients undergoing primary coronary artery bypass surgery (n = 9,862) between January 1995 and December 2004 at the Texas Heart Institute was performed. Diabetic (n = 3,374) and nondiabetic patients (n = 6,488) were classified into five groups, according to their body mass index: normal weight (n = 2,148), overweight (n = 4,257), mild obesity (n = 2,298), moderate obesity (n = 785), or morbid obesity (n = 338). Multivariate, stepwise logistic regression was performed controlling for patient demographics, medical history, and preoperative medications to determine whether obesity was independently associated with an increased risk of adverse postoperative outcomes.

Results: Obesity in nondiabetic patients was not independently associated with an increased risk of adverse postoperative outcomes. In contrast, obesity in diabetic patients was independently associated with a significantly increased risk of postoperative respiratory failure (odds ratio [OR], 2.26; 95% confidence interval [CI], 1.41-3.61; P < 0.001), ventricular tachycardia (OR, 2.27; 95% CI, 1.18-4.35; P < 0.02), atrial fibrillation (OR, 1.56; 95% CI, 1.03-2.38; P < 0.04), atrial flutter (OR, 2.38; 95% CI, 1.29-4.40; P < 0.01), renal insufficiency (OR, 1.66; 95% CI, 1.10-3.41; P < 0.03), and leg wound infection (OR, 5.34; 95% CI, 2.27-12.54; P < 0.001). Obesity in diabetic patients was not independently associated with an increased risk of mortality, stroke, myocardial infarction, sepsis, or sternal wound infection.  相似文献   

36.
37.
38.
39.
BACKGROUND: The tuberous breast presents a problem for which many surgical solutions have been described. Current teaching describes how the tuberous breast deformity is the result of skin shortage as well as herniation of breast tissue through the nipple-areola complex. However, through careful clinical observation we now believe that the only abnormality present is herniation of breast tissue through the nipple-areola complex. METHODS: Using this principle, we have refined a one-stage surgical procedure that can be used to correct any type of tuberous breast deformity. Since 2001 we have performed our technique on a series of 13 tuberous breasts of widely varying appearances in eight patients (age 17-24 years) with a follow up varying between 3 and 56 months. Our new understanding of the tuberous breast deformity has also made it possible to develop an objective, reproducible method for defining the tuberous breast based on the degree of areola herniation. RESULTS: All patients reported high levels of satisfaction with the procedure. Assessment of the results by an independent panel of attending surgeons showed all results to be good/excellent. Moreover, the results have improved with time and no revisions have been needed. Our method of defining the tuberous breast (based on the ratio of areola herniation:areola diameter) enabled us to identify a cut-off to decide (objectively) when a breast was tuberous. This allowed us to anticipate when an areola reduction/tightening procedure would be necessary to avoid a 'double-bubble' deformity. CONCLUSION: We propose a one-stage surgical procedure which is applicable to all degrees of tuberous breast deformity. The results appear to confirm our theory that the only abnormality present in the tuberous breast is herniation of breast tissue through the nipple-areola complex. In patients with small breasts and a tuberous deformity, correction of the herniation changes the tuberous breast into a simple hypoplastic breast. The volume deficit can then be corrected by augmentation (if desired by the patient). In patients with sufficient breast volume, correction of the herniation alone will correct the deformity.  相似文献   
40.
Objective To compare the clinical efficacy of postoperative intraperitoneal chemotherapy combined with systemic chemotherapy to systemic chemotherapy alone for serosa-involved colorectal cancer. Methods According to the criteria of serosa-involving in colorectal cancer, 332 cases were divided into 2 groups prospectively without randomization. Study group (n=166) was treated with intraperitoneal chemotherapy combined with systemic chemotherapy, and control group (n=166) with systemic chemotherapy alone. Incidence of local recurrence, peritoneal metastasis, hepatic metastasis, other distant metastasis and 3-year, 5-year overall survival (OS) rate of two groups were compared. Results 3-year and 5-year OS rates of stage Ⅱ B in study group were similar to those in control group (χ2=0.612,P=0.434). The above rates of stage Ⅲ in study group were higher than those in control group (χ2=3.989,P=0.046). Either the study group or the control group, the 3-year and 5-year OS rates of patients undergone laparoscopic surgery or open surgery were similar (P=0.839, P=0.172). Incidences of local recurrence, peritoneal metastasis and hepatic metastasis in study group were 1.9%, 3.8% and 3.8% respetively, lower than those in control group (8.2%,9.5% and 10.1%,P<0.05). Distant metastasis rate in study group was similar to that in control group. In study group, intraperitoneal chemotherapy regimen with Oxaliplatin had lower rates of peritoneal metastasis and hepatic metastasis as compared to that with Cisplatin (0.9% vs 8.8% ,P=0.019), while the incidences of local recurrence and other distant metastasis were similar. Conclusions Postoperative intraperitoneal chemotherapy combined with systemic chemotherapy improves 3-year and 5-year overall survival rates in patients with stage Ⅲ serosa-involved colorectal cancer, and decreases local recurrence, peritoneal metastasis and liver metastasis rate, especially when intraperitoneal chemotherapy regimen contains Oxaliphtin. Comparing with open surgery, laparoscopic surgery dose not improve 3-year and S-year overall survival rates in patients receiving combined chemotherapy or systemic chemotherapy alone.  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