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   408篇
  免费   22篇
  国内免费   32篇
儿科学   7篇
妇产科学   5篇
基础医学   27篇
口腔科学   14篇
临床医学   34篇
内科学   60篇
皮肤病学   12篇
神经病学   7篇
特种医学   114篇
外科学   24篇
综合类   86篇
预防医学   6篇
眼科学   3篇
药学   47篇
肿瘤学   16篇
  2022年   2篇
  2021年   3篇
  2020年   2篇
  2019年   1篇
  2018年   2篇
  2017年   4篇
  2016年   6篇
  2015年   5篇
  2014年   6篇
  2013年   11篇
  2012年   10篇
  2011年   8篇
  2010年   11篇
  2009年   15篇
  2008年   16篇
  2007年   28篇
  2006年   18篇
  2005年   15篇
  2004年   5篇
  2003年   8篇
  2002年   5篇
  2001年   8篇
  2000年   6篇
  1999年   9篇
  1998年   34篇
  1997年   23篇
  1996年   20篇
  1995年   19篇
  1994年   18篇
  1993年   15篇
  1992年   1篇
  1991年   6篇
  1990年   6篇
  1989年   16篇
  1988年   17篇
  1987年   11篇
  1986年   10篇
  1985年   4篇
  1984年   9篇
  1983年   9篇
  1982年   6篇
  1981年   10篇
  1980年   8篇
  1979年   1篇
  1978年   4篇
  1977年   3篇
  1976年   1篇
  1975年   7篇
排序方式: 共有462条查询结果,搜索用时 15 毫秒
91.
92.
A correct diagnosis and an understanding of the aetiology and dynamics of the processes involved in tooth resorption is critical to effective management. Tooth resorptions can be classified as: (1) trauma induced; (2) infection induced; or (3) hyperplastic invasive. Some transient trauma induced resorptions require no treatment but must be carefully monitored to check that there are no complicating issues such as infection. In cases of trauma induced replacement resorption, a multidisciplinary approach is usually necessary to ensure an optimal long-term solution. Infection induced tooth resorptions require the removal of the invading micro-organisms by endodontic therapy including intra-canal medication which can also facilitate repair of the resorbed tooth structure. The hyperplastic invasive tooth resorptions pose considerable challenges in management due to the complexity and aggressive nature of the resorptive process. With careful case selection and complete inactivation of resorptive tissue successful management can be achieved.  相似文献   
93.
The serotonin (5HT3) antagonist ondansetron was compared in a randomised study with metoclopramide and dexamethasone for the prevention of chemotherapy induced emesis. Thirty children aged 1-15 years with acute lymphoblastic leukaemia received 'intensification modules' according to the MRC United Kingdom acute lymphoblastic leukaemia regimen UKALL XI. This contains the moderately emetogenic drugs daunorubicin, etoposide, and cytarabine. Fifteen children received an intravenous loading dose of ondansetron followed by intravenous or oral doses 12 hourly for five days. Fifteen children received intravenous metoclopramide every six hours for three days with a loading dose of dexamethasone, repeated every eight hours for three days intravenously or orally. Efficacy was assessed by a diary card documenting the incidence of nausea, retching, or vomiting. In the 24 hour period after starting chemotherapy, ondansetron was more effective, with a complete or major response rate of 93%, compared with 33% using metoclopramide/dexamethasone.  相似文献   
94.
争光霉素A6和它在争光霉素复合物的地位   总被引:8,自引:0,他引:8  
争光霉素A5已鉴别为Bleomycin A6,在争光霉素复合物中所占比例一般在10%左右,在某些批样中可高达15%以上。文献报告Bleomycin A6在天然产的Bleomyein复合物中只有痕量。通过向发酵培养基中加入特定组分的末端胺可大大提高其特定组分在复合物中的含量比而其它组分的产生则不同程度地被抑制。但Bleomyein A6例外,即使向培养基中加入其末端胺精胺(0.3mg/ml),在所产生的复合物中大大增多的组分是Bleomyein A6,而Bleomycin A6仍只有痕量。这表明争光霉素产生菌有和Bleomycin产生菌明显不同的特点。  相似文献   
95.
96.
A survey for estimation of goitre in school children in the Rural Health Training Centre, Shirur area was undertaken. A total of 4664 students from 17 schools were surveyed. The goitre prevalence was found to be 59.8% with visible goitre rate of 6.2% in pre- and peri-adolescent (10–19 years) age group. Thus a highly endemic goitre focus was located in Shirur, area in Pune District (Maharashtra). This area is located on the eastern tail-end slopes of Sahyadri Hills in Balaghat ranges, situated at an altitude of 533 metres. The area is generally drought prone and receives scanty rain, with poor agricultural practices. Environmental deficiency of iodine was found to be the main cause for this high prevalence of goitre.KEY WORDS: Goitre endemic, Iodine  相似文献   
97.
Analysis of Rorschach response patterns of 30 adolescent schizophrenics and an equal number of age and sex matched normal adolescents was undertaken. Two of the five Thiesen''s patterns associated with schizophrenia, namely pattern C and D, occurred significantly more frequently in Rorschach responses of adolescent schizophrenics as compared to normal controls.KEY WORDS: Rorschach test, Schizophrenia  相似文献   
98.
Background Although eccrine poroma (EP) occurs preferentially in palmoplantar areas, pigmented variants of EP have not been documented on the palms and soles. Objectives We seek to confirm the notion regarding lack of pigmented EP on palmoplantar areas and determine whether the absence of pigmentation in palmoplantar EPs is due to lack of expression of melanocyte‐stimulating cytokines by tumour cells. Methods We searched the PubMed and Web of Science databases (1966–2006) for reports of pigmented EPs. In addition, a total of 17 EPs were collected from our pathology department. The presence of melanin was examined with haematoxylin‐eosin sections, and melanocyte colonization was shown by immunohistochemical stains for tyrosinase. In addition, immunohistochemical staining with antibodies to melanocyte‐stimulating cytokines, including endothelin‐1, stem cell factor, and nerve growth factor, was done on these tumours. Results A review of the literature revealed 15 pigmented EP reports, none of which were located in palmoplantar areas. Among 17 EPs collected from our pathology department, 7 occurred in palmoplantar areas and 10 in non‐palmoplantar areas. Three of the palmoplantar EPs and three of the non‐palmoplantar EPs showed positive staining with melanocyte‐stimulating cytokines. However, none of the palmoplantar EPs contained melanocytes or melanin pigment, wheras the three non‐palmoplantar EPs that stained positively with melanocyte‐stimulating cytokines were colonized with melanocytes and showed pigmentation clinically. Conclusions The expression of melanocyte‐stimulating factors by tumour cells is associated with melanocyte colonization in non‐palmoplantar EPs but not palmoplantar EPs. Therefore, the presence of melanocyte‐stimulating cytokines per se is not sufficient by itself to induce melanocyte colonization. Certain characteristics of palmoplantar skin, such as the dermal components of these anatomical sites, may play a role in inhibiting melanocyte colonization of EPs.  相似文献   
99.

Background

170 million people are infected with the Hepatitis C virus (HCV) around the world. Approximately 50%-70% patients infected with HCV develop chronic liver disease. Haemodialysis patients constitute an especially important group with high HCV prevalence. Outbreaks of HCV infection in dialysis units have been documented. Detection of anti-HCV antibodies is a convenient and conventional mode of documentation. However, in this group, it has it''s own caveats.

Methods

48 patients who had undergone or were on haemodialysis (HD) and had undergone a minimum of 15 dialysis sittings were studied. HCV infection was documented both by anti-HCV antibody detection and HCV RNA testing. A comparative evaluation of results by both tests was done.

Results

Out of a total of 48 patients, HCV RNA was detected in 38 (79.16%) and anti-HCV antibodies in 13(27.07%). Out of 48 patients 10(20.83%) were negative for both parameters. 22.91% (11/48) of patients were positive for both HCV RNA and anti-HCV antibody. 56.25% (27/48) were HCV RNA positive but anti-HCV antibodies were not detectable in their sera. 2 patients (04.16%) had a positive anti-HCV antibody status despite HCV RNA being negative. In 20.83% (10/48) both parameters were undetectable.

Conclusion

Chronic liver disease (CLD), particularly due to HCV infection, is a major complication amongst haemodialysis (HD) patients. Without reliable assays for antigenemia and the inability of antibody tests to define viremia in all cases, the detection of viral nucleic acid is necessary for diagnosis of active HCV infection.Key Words: Hepatitis C virus, Haemodialysis  相似文献   
100.
目的:探讨瞬时性受体电位通道香草酸受体5、6与骨代谢的关系。资料来源:应用计算机检索PubMed数据库1999-01/2006-07相关瞬时性受体电位通道方面的文献,检索词“TRPV”,限定文献语言种类为English。资料选择:对资料进行初审,选取包括瞬时性受体电位通道香草酸受体5、6的文献,开始查找全文。纳入标准:对两者及瞬时性受体电位通道家族进行研究的文章。排除标准:研究内容局限于瞬时性受体电位通道香草酸受体1~4的文章。资料提炼:共检索到106篇关于瞬时性受体电位通道香草酸受体的文献,最终纳入30篇符合标准的文献。资料综合:瞬时性受体电位通道香草酸受体5、6是瞬时性受体电位通道超家族中的成员,是专门的上皮样钙离子通道。目前研究已经证明它们在肠道和肾脏等组织中有表达,并对跨细胞钙离子转运起着关键性调控作用。但在骨组织中表达情况相关报道较少,在骨代谢机制上的研究更少,本文针对目前两者与骨代谢的关系进行综述。结论:深入研究瞬时性受体电位通道香草酸受体5、6钙离子通道在骨代谢中的作用,对于那些与骨代谢相关疾病的治疗将能从分子水平上找到解决的方法。  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