全文获取类型
收费全文 | 4259篇 |
免费 | 236篇 |
国内免费 | 80篇 |
专业分类
耳鼻咽喉 | 26篇 |
儿科学 | 129篇 |
妇产科学 | 100篇 |
基础医学 | 748篇 |
口腔科学 | 169篇 |
临床医学 | 422篇 |
内科学 | 673篇 |
皮肤病学 | 141篇 |
神经病学 | 398篇 |
特种医学 | 389篇 |
外科学 | 590篇 |
综合类 | 49篇 |
一般理论 | 1篇 |
预防医学 | 189篇 |
眼科学 | 94篇 |
药学 | 207篇 |
中国医学 | 8篇 |
肿瘤学 | 242篇 |
出版年
2022年 | 23篇 |
2021年 | 49篇 |
2020年 | 38篇 |
2019年 | 40篇 |
2018年 | 73篇 |
2017年 | 53篇 |
2016年 | 65篇 |
2015年 | 100篇 |
2014年 | 109篇 |
2013年 | 111篇 |
2012年 | 183篇 |
2011年 | 198篇 |
2010年 | 150篇 |
2009年 | 173篇 |
2008年 | 174篇 |
2007年 | 195篇 |
2006年 | 173篇 |
2005年 | 145篇 |
2004年 | 163篇 |
2003年 | 124篇 |
2002年 | 119篇 |
2001年 | 102篇 |
2000年 | 134篇 |
1999年 | 113篇 |
1998年 | 105篇 |
1997年 | 95篇 |
1996年 | 83篇 |
1995年 | 73篇 |
1994年 | 60篇 |
1993年 | 65篇 |
1992年 | 74篇 |
1991年 | 54篇 |
1990年 | 77篇 |
1989年 | 87篇 |
1988年 | 75篇 |
1987年 | 54篇 |
1986年 | 44篇 |
1985年 | 66篇 |
1984年 | 44篇 |
1983年 | 22篇 |
1982年 | 24篇 |
1980年 | 26篇 |
1979年 | 30篇 |
1978年 | 25篇 |
1977年 | 36篇 |
1976年 | 26篇 |
1975年 | 28篇 |
1974年 | 26篇 |
1971年 | 26篇 |
1880年 | 32篇 |
排序方式: 共有4575条查询结果,搜索用时 31 毫秒
1.
Paul J. Devlin Brian W. McCrindle James K. Kirklin Eugene H. Blackstone William M. DeCampli Christopher A. Caldarone Ali Dodge-Khatami Pirooz Eghtesady James M. Meza Peter J. Gruber Kristine J. Guleserian Bahaaladin Alsoufi Linda M. Lambert James E. OBrien Erle H. Austin Jeffrey P. Jacobs Tara Karamlou 《The Journal of thoracic and cardiovascular surgery》2019,157(2):684-695.e8
Objective
Arch obstruction after the Norwood procedure is common and contributes to mortality. We determined the prevalence, associated factors, and practice variability of arch reintervention and assessed whether arch reintervention is associated with mortality.Methods
From 2005 to 2017, 593 neonates in the Congenital Heart Surgeons' Society Critical Left Heart Obstruction cohort underwent a Norwood procedure. Median follow-up was 3.7 years. Multivariable parametric models, including a modulated renewal analysis, were performed.Results
Of the 593 neonates, 146 (25%) underwent 218 reinterventions for arch obstruction after the Norwood procedure: catheter-based (n = 168) or surgical (n = 50) at a median age of 4.3 months (quartile 1-quartile 3, 2.6-5.7). Interdigitation of the distal aortic anastomosis was protective against arch reintervention. Development of ≥ moderate tricuspid valve regurgitation and right ventricular dysfunction at any point was associated with arch reintervention. Nonsignificant variables for arch reintervention included shunt type and preoperative aortic measurements. Surgical arch reintervention was protective against arch reintervention, but transcatheter reintervention was associated with increased reintervention. Arch reintervention was not associated with increased mortality. There was wide institutional variation in incidence of arch reintervention (range, 0-40 reinterventions per 100 years patient follow-up) and in preintervention gradient (range, 0-64 mm Hg).Conclusions
Interdigitation of the distal aortic anastomosis during the Norwood procedure decreased the risk of arch reintervention. Surgical arch reintervention is more definitive than transcatheter. Arch reintervention after the Norwood procedure is not associated with increased mortality. Serial surveillance for arch obstruction, integrated with changes in right ventricular function and tricuspid valve regurgitation, is recommended after the Norwood procedure to improve outcomes. 相似文献2.
Mycophenolate mofetil (MMF) is increasingly used to prevent acute and chronic rejection following kidney transplantation and in autoimmune diseases. Here, we report on a patient after kidney transplantation, who developed an acute inflammatory syndrome characterized by fever and oligoarthritis within 1 week after increasing the MMF dosage. MMF was discontinued resulting in a complete resolution of the syndrome within 48 h. We demonstrated in vitro that the patient's phorbol myristate acetate (PMA-) and formyl Met-Leu-Phe (fMLP-) stimulated polymorphonuclear neutrophils (PMNs) developed increased oxidative burst when incubated with MMF. This report demonstrates that MMF can also induce acute inflammatory syndrome in patients following kidney transplantation and that this syndrome might be due to a paradox, pro-inflammatory reaction of PMNs. 相似文献
3.
P Avalos-Peralta† A Herrera† JJ Ríos-Martín‡ AM Pérez-Bernal† D Moreno-Ramírez† F Camacho† 《Journal of the European Academy of Dermatology and Venereology》2006,20(1):79-83
We report the case of a patient with a 13-year history of pemphigus vulgaris (PV) treated with immunosuppressive agents, prednisone and mycophenolate mofetil who had developed lesions of Kaposi's sarcoma (KS) on a sole plaque of PV that had been previously treated with intralesional injections of steroids. The lesions were surgically removed and polymerase chain reaction (PCR) demonstrated human herpesvirus-8 (HHV-8) DNA. There were neither recurrences nor later dissemination of KS following gradual decrease of the immunosuppressive therapy. We suggest that the treatment with intralesional steroids may have influenced the local reactivation of a latent infection of the virus, determining the appearance of this localized KS. 相似文献
4.
5-Amino-4-imidazolecarboxamide (AICA) riboside, the nucleoside corresponding to AICA ribotide (AICAR or ZMP), an intermediate of the de novo pathway of purine biosynthesis, was found to exert a dose-dependent inhibition on gluconeogenesis in isolated rat hepatocytes. Production of glucose from lactate-pyruvate mixtures was half-maximally inhibited by approximately 100 microM and completely suppressed by 500 microM AICA riboside. AICA riboside also inhibited the production of glucose from all other gluconeogenic precursors investigated, i.e., fructose, dihydroxyacetone, and L-proline. Measurements of intermediates of the glycolytic-gluconeogenic pathway showed that AICA riboside provoked elevations of triose phosphates and fructose-1,6-bisphosphate and decreases in fructose-6-phosphate and glucose-6-phosphate. The effects of AICA riboside persisted when the cells were washed 10 min after its addition but were suppressed by 5-iodotubercidin, an inhibitor of adenosine kinase. AICA riboside provoked a dose-dependent buildup of normally undetectable Z nucleotides. After 20 min of incubation with 500 microM AICA riboside, ZMP, ZTP, and ZDP reached 3, 0.3, and 0.1 mumol/g cells, respectively. Concentrations of ATP were not significantly modified by addition of up to 500 microM AICA riboside when the cells were incubated with lactate-pyruvate but decreased with fructose or dihydroxyacetone. The activity of rat liver fructose-1,6-bisphosphatase was inhibited by ZMP with an apparent Ki of 370 microM. It is concluded that AICA riboside exerts a suppressive effect on gluconeogenesis because it provokes an accumulation of ZMP, which inhibits fructose-1,6-bisphosphatase.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
5.
Thymuses of rats that had been: a) gamma-irradiated [500 cGy whole-body radiation (R)], or b) thermally injured [20% BSA dorsal, scald burn (TI)], or c) combined injured [irradiation followed by burn (CI)] were studied for involution and recovery processes after sublethal treatments. The expression of surface antigens on thymic cells before and after injuries was evaluated using the monoclonal antibodies (mcAB) MRC OX4, MRC OX7, MRC OX8, W3/13 HLK, and W3/25 and flow cytometric analysis. Thymic cellularity decreased to less than 1% of normal (N), age-matched rats by 4 days after R or CI. Recovery reached 60% to 70% of N by 28 days post treatments. TI caused a biphasic thymic recovery pattern with nadirs of 40% of N on days 7 and 21. Recovery at day 28 was similar to that after R and CI. Expression of OX7, OX8, W3/13, and W3/25 antigens all reached nadirs of 40% of N by day 4 after R and CI. Recovery of antigen expression, except for W3/25, was near completion by day 7 after R and CI. Changes in antigen expression after TI were less pronounced for all mcAB tested. Decreases in labeling of thymocytes with the helper T-cell marker, W3/25, observed after TI, could not be correlated with elevated expressions of the suppressor/cytotoxic T-lymphocyte antigen, OX8. Variations in relative labeling of nonlymphoid thymic cells with OX4 (Ia-antigen) reflected the disappearance and recovery of radiosensitive lymphoid thymocytes. The similarity of results after R and CI demonstrate that the model of CI is 'radiation-dominated.' The addition of burn injury to radiation trauma had no synergistically damaging effect on the parameters studied. 相似文献
6.
CM Reid M. Nelson P. Beckinsale P. Ryan LMH Wing LJ Beilin MA Brown GLR Jennings CI Johnston J. Marley JJ McNeil TO Morgan J. Shaw ID Steven MJ West 《Clinical and experimental pharmacology & physiology》1997,24(5):370-373
1. The present study aimed to determine the feasibility of conducting a 5 year cardiovascular outcome trial of the treatment of 6000 elderly hypertensive patients in Australian general practices. 2. General practitioners (GPs) were invited to participate by mail and personal follow-up. Patient records were reviewed to identify subjects for a blood pressure (BP) screening programme. Blood pressure was measured on three occasions and eligible subjects were included if the average BP was 160 mmHg systolic or 90 mmHg diastolic if systolic BP was 140 mmHg. 3. Seven hundred and forty-one GPs were approached and 89 were enrolled in the study (12% of mail invites and 75% of those receiving a personal contact). In 16 practices where screening was completed, 82 000 records were reviewed to identify 4% patients eligible for screening. Twenty-two per cent of eligible subjects attended screening. Of 1938 subjects screened, 180 (9%) had BP 5=160/90 mmHg. Forty-seven percent of subjects (n = 916) were receiving antihypertensive therapy and 184 (20%) were withdrawn from therapy. One hundred and sixteen (63%) of these subjects had BP return to study entry levels within 6 weeks. Fifty-seven newly diagnosed and 81 previously treated subjects were randomized (7% of the screened population). 4. Based on the high participation rate of GPs, the response rate of patients to attend a BP screening programme and the 7% randomization to screening ratio for entry into the study, the ANBP2 pilot study has demonstrated that it is feasible to recruit subjects from Australian general practices to a cardiovascular outcome trial. 相似文献
7.
8.
S M Haffner K K Gruber P A Morales H P Hazuda R A Valdez B D Mitchell M P Stern 《American journal of epidemiology》1992,136(9):1060-1068
There is considerable evidence that lipoprotein(a) (Lp(a)) is a strong independent risk factor for coronary heart disease. Based on their risk factor profile, Mexican Americans have an increased risk of coronary heart disease, yet Mexican Americans have coronary heart disease mortality similar to or lower than that of non-Hispanic whites. The authors therefore attempted to determine whether Mexican Americans had decreased Lp(a) concentrations relative to non-Hispanic whites in the San Antonio Heart Study, a population-based study of diabetes and cardiovascular disease. Lp(a) concentrations (mg/dl) were significantly lower in Mexican Americans (n = 316) than in non-Hispanic whites (n = 242) (men: 10.4 vs. 16.3; women: 11.5 vs. 16.4). In addition, the proportion of persons with Lp(a) concentrations of > or = 30 mg/dl (the threshold at which increased risk of coronary heart disease is believed to occur) was significantly higher in non-Hispanic whites than in Mexican Americans (18.6% vs. 7.6%; Mantel-Haenszel odds ratio (adjusted for sex) = 2.79). Age, obesity, body fat distribution, cigarette smoking, alcohol consumption, and glucose and insulin concentrations were not significantly related to Lp(a) levels. Decreased Lp(a) concentrations may account in part for Mexican Americans' relative protection from coronary heart disease mortality. 相似文献
9.
U F Gruber 《Anti-cancer drugs》1990,1(2):187-197
Long lasting occupational exposure to asbestos dust may cause skin corns, benign pleural effusion, hyaline plaques of the parietal pleura, diffuse thickening of the pulmonary pleura, and asbestosis, i.e. diffuse interstitial pulmonary fibrosis. Malignant disorders include lung cancer and mesothelioma of the pleura, peritoneum and pericardium. In general, many years elapse from first exposure to the appearance of symptoms. Almost all these diseases are the result of dusty working conditions more than 20 years ago. In spite of the fact that the general public is invariably exposed to small amounts of the material, asbestos is not a public health problem. Even living in a building containing sprayed asbestos is calculated to produce a lifetime risk of death which is negligible. There is no evidence to indicate that ingested asbestos fibres represent a major health problem. 相似文献
10.
Effects of sex on differences in awareness, treatment, and control of high blood pressure 总被引:1,自引:0,他引:1
Our purpose was to explain the reasons for sex differentials in the awareness, treatment, and control of hypertension by identifying major social and behavioral predictors of these three sequential stages of high blood pressure control. We analyzed data on all 1,433 hypertensive subjects from the First Connecticut Blood Pressure Survey. Hypertensive women were more likely than hypertensive men to be aware of their high blood pressure (odds ratio = 1.40; confidence interval = 1.10-1.79) and to have controlled levels of blood pressure (odds ratio = 1.62; confidence interval = 1.08-2.44). Men and women who were aware of their hypertension were equally likely to be treated. Sex still explained differences in awareness and control of hypertension after adjusting for other significant variables. We conclude that sex is an important predictive covariate for adjustment in explaining differences in awareness and control of high blood pressure. Health care professionals should be aware of the differential role of sex when informing and treating hypertensive patients. 相似文献