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   11359篇
  免费   622篇
  国内免费   40篇
耳鼻咽喉   217篇
儿科学   372篇
妇产科学   206篇
基础医学   1328篇
口腔科学   313篇
临床医学   729篇
内科学   2941篇
皮肤病学   353篇
神经病学   741篇
特种医学   237篇
外国民族医学   1篇
外科学   1789篇
综合类   121篇
一般理论   4篇
预防医学   822篇
眼科学   299篇
药学   830篇
中国医学   50篇
肿瘤学   668篇
  2023年   60篇
  2022年   105篇
  2021年   319篇
  2020年   165篇
  2019年   313篇
  2018年   471篇
  2017年   264篇
  2016年   262篇
  2015年   270篇
  2014年   362篇
  2013年   498篇
  2012年   826篇
  2011年   913篇
  2010年   431篇
  2009年   362篇
  2008年   745篇
  2007年   752篇
  2006年   762篇
  2005年   695篇
  2004年   635篇
  2003年   570篇
  2002年   530篇
  2001年   184篇
  2000年   199篇
  1999年   187篇
  1998年   60篇
  1997年   46篇
  1996年   54篇
  1995年   48篇
  1994年   38篇
  1993年   22篇
  1992年   66篇
  1991年   58篇
  1990年   55篇
  1989年   52篇
  1988年   45篇
  1987年   59篇
  1986年   51篇
  1985年   44篇
  1984年   38篇
  1983年   43篇
  1982年   31篇
  1981年   27篇
  1980年   20篇
  1979年   31篇
  1978年   22篇
  1977年   19篇
  1975年   17篇
  1974年   33篇
  1973年   18篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
991.
The number of foreign residents in Spain increased significantly with Moroccans and Algerians as the 2 largest nationalities. However, there are no studies that analyze their awareness of living kidney donation although an increasing number of patients of these nationalities are included on the waiting list.The aim of this study is to analyze the attitude toward living kidney donation among the population of Spain residents born in Algeria.

Methods

The study population was Spain residents born in Algeria. A sample of the population older than 15 years was obtained randomly and stratified by age and sex. Attitude was assessed using a validated questionnaire on psychosocial aspects toward living kidney donation (PCID-DVR Rios). A random selection of people to be surveyed was carried out.

Results

Of the 420 respondents, 64% of respondents are in favor of related living kidney donation (family or friends). The remaining 36% were against or undecided. The factors associated with this attitude are personal reasons and family (P < .001). Psychosocial factors are not related to this attitude (P < .001). The following factors were associated with this attitude: (1) not being concerned about the possible mutilation of the body after donation (P < .001) and (2) evaluation of the risk from living kidney donation (P < .001).

Conclusions

The attitude toward related living kidney donation among the population of Spain residents born in Algeria is unfavorable. Only 64% would do it, and it is associated with affective factors and the evaluation of the risk from living kidney donation.  相似文献   
992.

Introduction

The immunorejection in xenotransplantation has mostly been studied from the host's immune system activation point of view and there is very little information about the graft-vs-host reaction.

Objectives

To validate an enzyme-linked immunosorbent assay (ELISA) test for porcine IgM and IgG quantitation, the assessment of porcine IgG and IgM in sera samples from baboons after liver orthotopic xenotransplantation or in human plasma after xenotransfusion through pig organs, and to assess the presence of porcine immunoglobulin in a baboon after plasmapheresis to a complete change of plasma after 4 passages through pig liver.

Materials and Methods

Two commercial ELISA kits for pig IgG and IgM quantitation were evaluated for cross reactivity with samples from baboons, Rhesus monkeys, squirrel monkeys, and humans. Then, samples from 18 baboons after orthotopic liver xenotransplantation were studied for porcine IgG and IgM. To understand the phenomenon, human plasma samples after xenotransfusion 1, 2, 3, or 4 times through liver or kidney were assessed for porcine IgG presence and finally, the porcine IgG were quantified in sera samples obtained during more than 4 years from a baboon after plasmapheresis with baboon plasma after xenotransfusion 4 times through a pig liver.

Results

Porcine IgG and IgM were found in samples from xenotransplanted baboon during all survival. The quantity of porcine IgG in plasma after xenotransfusion correlated with the number of passages through the pig liver, and the IgG were completely cleared from the baboon 16 days after plasmapheresis and complete substitution of plasma after 4 xenotransfusions through a pig liver.  相似文献   
993.
Living kidney related donations (LKRD) should be promoted because of the current deficit of organs for transplantation. The objective of the study was to analyze the attitude of Spanish veterinary students toward LKRD, because they may influence public opinion in the future, and to determine the factors that condition it.

Methods

A sociological, interdisciplinary, multicenter, and observational study was carried out in the veterinary students enrolled in Spain (n = 9000) in the university academic year 2010–2011. A sample of 2815 students was stratified by geographical area and academic year. The students' attitude toward LKRD was assessed using a psychosocial validated questionnaire (PCID-DVR Rios), was self-administered, and was completed anonymously. Veterinary schools were randomly selected. The questionnaire was applied to each academic year at compulsory sessions. Statistical analysis was preformed using t test, χ2 test, and logistic regression analysis.

Results

The completion rate was 95% (n = 2683); 93% (n = 2504) were in favor of LKRD and 36% (n = 945) supported unrelated living kidney donation. The following variables were associated with having a more favorable attitude: (1) sex (P < .001), (2) being a student of southern universities (P = .03), (3) attitude toward deceased donation (P < .001), (4) having a father (P < .001) or a mother (P < .001) in favor of organ donation, and (5) having discussed the subject with friends (P = .03) or family (P = .02). However, only 60% would accept a kidney from a relative.

Conclusion

Spanish veterinary students have a favorable attitude toward LKRD. However, only 60% would accept a kidney from a relative.  相似文献   
994.
The Senegalese population is an emerging group in Europe. The number of foreign residents in Spain, France, and Italy has increased significantly. However, there are no studies that analyze their awareness of organ donation and transplantation.

Objective

To analyze the attitude toward organ donation among the population born in Senegal residing in Spain.

Methods

The study population was born in Senegal and resides in Spain. A sample of the population older than 15 years was obtained randomly and stratified by age and sex according to census data and immigrant support associations. Attitude was assessed using a validated questionnaire on psychosocial aspects toward organ donation (PCID-DTO Rios). A random selection of people to be surveyed was carried out. Assistance from African immigration support associations in Spain was needed to advise on the location of potential respondents. The survey was self-administered and completed anonymously.

Results

A sample of 295 respondents was included in the study. Attitude toward deceased donation was favorable in 37% (n = 109) of respondents; 35% (n = 104) were against and 28% (n = 82) were undecided.Several variables were associated with having a more favorable attitude (P < .05): sex, having discussed donation with the family, not being concerned about the possible mutilation of the body after donation, the respondent's religion, and knowledge of one's partner's attitude in favor of organ donation.

Conclusions

The attitude toward organ donation among the population born in Senegal and residing in Spain is unfavorable, and it is associated with psychosocial factors.  相似文献   
995.

Introduction

Awareness about organ donation among the general population is fundamental to organ donation programs. It is important to determine the factors that influence attitudes toward organ donation within the general population in order to carry out cost-effective campaigns.

Objective

To analyze the attitude toward organ donation among Santiago, Cuba, citizens.

Methods

The study population encompassed residents in Santiago, Cuba. A sample population of residents older than 15 years was obtained randomly and stratified by age and sex. Attitude was assessed using a validated questionnaire on psychosocial aspects toward organ donation and transplant (PCID-DTO Ríos). Available census data were used. The survey was self-administered and completed anonymously.

Results

Of the 455 respondents, 70% of respondents are in favour of cadaveric donation, 16% are against, and 14% were undecided. Several variables were associated with having a more favorable attitude. And in the multivariate analysis, the following variables continue to feature as independent variables: 1. knowledge of the concept of brain death [OR = 2.386 (4.761–1.194); P = .014]; 2. being in favor of donating a family member's organs [OR = 3.067 (5.952–1.584); P = .001]; 3. a partner's favorable attitude [OR = 5.795 (1.477–22.731); P = .012]; 4. being an atheist/agnostic as the religious beliefs [OR = 1.845 (3.289–1.038); P = .037]; 5. not being concerned about the possible mutilation of the body after donation [OR = 7.437 (2.918–18.955); P < .001]; 6. not accepting other treatment options after death, such as inhumation [OR = 3.048 (5.714–1.626); P = .001].

Conclusions

The attitude toward cadaveric organ donation among the Santiago, Cuba population is favorable and it is associated with several psychosocial factors.  相似文献   
996.
997.
998.
Oxidative stress is implicated in the pathogenesis of non-alcoholic fatty liver disease (NAFLD). In the present study, hepatic and plasma oxidative stress-related parameters were measured and correlated with clinical and histological findings in 31 NAFLD patients showing increased body mass index. Liver protein carbonyl content was enhanced by 403% in patients with steatosis (n=15) compared with control values (n=12), whereas glutathione content, superoxide dismutase (SOD) activity and the ferric reducing ability of plasma (FRAP) were decreased by 57%, 48% and 21% (P<0.05) respectively. No changes in microsomal p-nitrophenol hydroxylation and the total content of cytochrome P450 (CYP) or CYP2E1 were observed. Patients with steatohepatitis (n=16) exhibited protein carbonyl content comparable with that of controls, whereas glutathione content, SOD and catalase activities were decreased by 27%, 64% and 48% (P<0.05). In addition, FRAP values in patients with steatohepatitis were reduced by 33% and 15% (P<0.05) when compared with controls and patients with steatosis respectively, whereas p-nitrophenol hydroxylation (52%) and CYP2E1 content (142%) were significantly increased (P<0.05) compared with controls. It is concluded that oxidative stress is developed in the liver of NAFLD patients with steatosis and is exacerbated further in patients with steatohepatitis, which is associated with CYP2E1 induction. Substantial protein oxidation is followed by proteolysis of the modified proteins, which may explain the co-existence of a diminished antioxidant capacity and protein oxidation in the liver of patients with steatohepatitis.  相似文献   
999.
1000.
Direct myocardial revascularization techniques has earned great acceptance in the treatment of ischemic coronary syndromes in the past two decades. Almost since its beginnings the procedure was done with the aid of extracorporeal circulation, since the technical accessibility with cardiac standstill further helped to evolve the procedure. As years went by, complications due to the use of the pump became evident, such as microembolism, bleeding disorders, and others. Besides this, there is a special group of patients, those with high surgical risk, with preexisting pulmonary, hepatic or cerebral disease, who benefit a great deal when bypass grafting procedure is done without the pump. In this article we delineate the indications, contraindications, and the procedure itself based in our personal experience, reporting our first five patients with this technique.  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