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   849篇
  免费   83篇
  国内免费   18篇
耳鼻咽喉   2篇
儿科学   17篇
妇产科学   22篇
基础医学   124篇
口腔科学   16篇
临床医学   142篇
内科学   169篇
皮肤病学   10篇
神经病学   57篇
特种医学   18篇
外科学   68篇
综合类   54篇
一般理论   1篇
预防医学   101篇
药学   49篇
中国医学   8篇
肿瘤学   92篇
  2023年   11篇
  2022年   19篇
  2021年   38篇
  2020年   18篇
  2019年   30篇
  2018年   34篇
  2017年   26篇
  2016年   24篇
  2015年   38篇
  2014年   44篇
  2013年   49篇
  2012年   66篇
  2011年   59篇
  2010年   32篇
  2009年   33篇
  2008年   56篇
  2007年   63篇
  2006年   42篇
  2005年   86篇
  2004年   31篇
  2003年   40篇
  2002年   37篇
  2001年   3篇
  2000年   2篇
  1999年   11篇
  1998年   8篇
  1997年   8篇
  1996年   3篇
  1995年   4篇
  1994年   4篇
  1993年   4篇
  1992年   7篇
  1991年   5篇
  1990年   2篇
  1988年   4篇
  1987年   2篇
  1986年   4篇
  1985年   2篇
  1984年   1篇
排序方式: 共有950条查询结果,搜索用时 46 毫秒
1.
耳源性脑疝25例,抢救成功者19例。采用单纯脑脓肿穿刺抽脓抢救脑疝6例,仅1例成功;开颅减压术抢救脑疝20例,18例抢救成功。本组临床实践和文献报道都说明耳源性脑疝一旦发生应即刻行开颅减压术,能卓有成效地抢救生命  相似文献   
2.
谢渭芬  曹蕙婷 《免疫学杂志》1994,10(1):56-58,62
制备出两株分泌抗PⅢP(Ⅲ型前胶原肽)单克隆抗体的杂交瘤细胞株。竞争抑制ELISA试验表明:两株单抗与PCI(Ⅰ型前胶原)及CⅢ(Ⅲ型胶原)无交叉反应。Dot-ELISA示两株单抗钧针对PⅢP构象决定簇。应用所制备的单抗对人肝细胞癌组织及大鼠、小鼠成纤维母细胞进行免疫定位。结果显示两种成纤维母细胞呈明显膜阳性;肝癌细胞浆内呈粗颗粒状染色,提示肝癌细胞具有合成Ⅲ型前胶原的能力。  相似文献   
3.
囊性肾癌的CT、超声影像分析(附13例报告)   总被引:8,自引:1,他引:7  
目的 探讨囊性肾癌的CT、超声特点及诊断价值。资料与方法 回顾性分析13例经手术病理证实的囊性肾癌的CT和超声表现。结果 CT及超声对囊性。肾癌的诊断准确性高,其主要特点为囊壁及分隔的不规则增厚、囊壁结节、钙化,囊液混浊,实性部分增强后强化,实性部分或分隔上出现彩色血流。结论 CT及超声检查对囊性肾癌有较高的诊断价值,但对不典型者可误诊为良性囊肿,应行超声引导下穿刺活检。  相似文献   
4.
5.
6.
BACKGROUND: Children with poorly controlled asthma are at high risk of airway remodeling, sleep disruption, school absenteeism, and limited participation in activities. OBJECTIVE: To determine asthma prevalence and characterize disease severity and burden in school-aged children. METHOD: A case-finding study was conducted via a multiple-choice questionnaire and asthma algorithm. Items used for analysis include physician diagnosis of asthma, symptom severity, and health care utilization. The chi2 test was used to determine the significance of differences among cases. Logistic regression was used to evaluate the association of patient factors and asthma indicators. RESULTS: Of the 5,417 children surveyed, 1,341 (25%) were classified as being at risk of asthma. Of these asthma cases, 55% were positive by diagnosis and algorithm (active), 10% were positive per algorithm alone (suspected), and 35% were positive per diagnosis alone (nonactive). Only 14% of all asthma cases reported experiencing no respiratory symptoms (< 1% active, 2% suspected, and 40% nonactive) compared with 75% of noncases. Also, 75% of noncases reported never missing school compared with 19%, 33%, and 54% of active, suspected, and nonactive asthma cases. African American race, Medicaid enrollment, and male sex were independent predictors of asthma risk. Similarly, African American race, Medicaid enrollment, age, and persistent asthma were independent predictors of emergency department use among asthma cases. DISCUSSION: Prevalence of active symptoms suggestive of poor asthma control was extremely high among urban, minority children enrolled in Arkansas' largest public school district. Poor asthma control greatly affects quality of life, including school attendance and performance. Interventions should raise expectations and emphasize the importance of achieving asthma control.  相似文献   
7.
BACKGROUND: Little is known about the level of knowledge and comfort with bariatric surgery among family practice physicians. METHODS: Surveys were sent to all family practitioners in Connecticut querying the practice type and knowledge of bariatric surgery. The results were analyzed for the prevalence of opinion. RESULTS: Of 620 surveys sent out, 129 (21%) were completed. Of the 129 respondents, 73% were men, aged 31-79 years, and 92% were board certified, with an average of 19 years' experience. The average body mass index of respondents was 26 kg/m2 (range 16-40). Only 4% of respondents had a body mass index >30 kg/m2. Physicians reported a patient obesity rate of 43%. Of the 129 respondents, 88% believed obesity was difficult to control with diet and exercise alone. Only 6% thought obesity was best controlled surgically. Also, 85% of respondents had referred a patient for gastric bypass, although only 57% were comfortable explaining the procedure. The most common reason for refusal to refer was fear of complications and death. Additionally, 55% correctly listed a body mass index of 40 kg/m2 as qualifying for bariatric surgery without comorbidities; 48% identified the mortality rate of surgery as <1%, with 4% of respondents reporting >10%; and 84% were familiar with gastric bypass, 66% with LapBand, 33% with vertical banded gastroplasty, and 5% with duodenal switch. The respondents believed that nausea was the most common side effect, followed by anemia and fatigue. Finally, 53% believed bowel obstruction was common. CONCLUSIONS: The results of our study have shown that misconceptions about bariatric surgery exist in the family practice community despite the increasing frequency of these procedures. Educational programs need to be designed to assist family practitioners in treating and referring obese patients.  相似文献   
8.
目的 探讨胆囊息肉样痛变的诊断及治疗。方法 回顾性总结分析胆囊息肉样病变56例的临床资料。结果 胆固醇性息肉多为多发且直径小于10mm。结论 B超诊断胆囊息肉是最有效的方法,同时胆固醇性息肉的治疗应注意调节和控制胆固醇代谢,对单发息肉直径大于10mm以上,伴有胆囊结石病人,应该采取手术治疗。  相似文献   
9.
Presently, in our society, thousands of children, adolescents, and adults are physically, mentally, and emotionally traumatized from exposure to domestic violence (DV). Exposure to DV, defined here as male violence against their female partners, occurs among all ethnic, cultural, socioeconomic, geographical, and racial groups. DV can lead to depression, negative self‐esteem, and general psychological distress in women. Children exposed to DV have an increased risk of behavioral, emotional, and social problems. DV shelters often provide group counseling and support services for battered women, children, and adolescents residing there, but the programs do not reach the majority of women living in the broader community. Furthermore, few studies have examined the effectiveness and efficacy of support group treatment intervention programs for battered women and children. This is due, in part, to the methodological difficulties inherent in this design. As a way to meet the needs of families that have experienced DV, academic researchers from a Midwestern university and a director of counseling services from a local domestic violence agency have partnered to offer a psycho‐educational intervention designed to  相似文献   
10.
Telomere proteins protect the chromosomal terminus from nucleolytic degradation and end-to-end fusion, and they may contribute to telomere length control and the regulation of telomerase. The current studies investigate the effect of Oxytricha single-stranded telomere DNA-binding protein subunits α and β on telomerase elongation of telomeric DNA. A native agarose gel system was used to evaluate telomere DNA-binding protein complex composition, and the ability of telomerase to use these complexes as substrates was characterized. Efficient elongation occurred in the presence of the α subunit. Moreover, the α–DNA cross-linked complex was a substrate for telomerase. At higher α concentrations, two α subunits bound to the 16-nucleotide single-stranded DNA substrate and rendered it inaccessible to telomerase. The formation of this α·DNA·α complex may contribute to regulation of telomere length. The α·β·DNA ternary complex was not a substrate for telomerase. Even when telomerase was prebound to telomeric DNA, the addition of α and β inhibited elongation, suggesting that these telomere protein subunits have a greater affinity for the DNA and are able to displace telomerase. In addition, the ternary complex was not a substrate for terminal deoxynucleotidyltransferase. We conclude that the telomere protein inhibits telomerase by rendering the telomeric DNA inaccessible, thereby helping to maintain telomere length.  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