全文获取类型
收费全文 | 51152篇 |
免费 | 2685篇 |
国内免费 | 178篇 |
专业分类
耳鼻咽喉 | 738篇 |
儿科学 | 2949篇 |
妇产科学 | 914篇 |
基础医学 | 6076篇 |
口腔科学 | 1413篇 |
临床医学 | 3687篇 |
内科学 | 10055篇 |
皮肤病学 | 1459篇 |
神经病学 | 3077篇 |
特种医学 | 1407篇 |
外国民族医学 | 2篇 |
外科学 | 7721篇 |
综合类 | 1439篇 |
一般理论 | 21篇 |
预防医学 | 2895篇 |
眼科学 | 1704篇 |
药学 | 4781篇 |
1篇 | |
中国医学 | 400篇 |
肿瘤学 | 3276篇 |
出版年
2023年 | 385篇 |
2022年 | 1062篇 |
2021年 | 1926篇 |
2020年 | 1039篇 |
2019年 | 1292篇 |
2018年 | 1866篇 |
2017年 | 1262篇 |
2016年 | 1577篇 |
2015年 | 1595篇 |
2014年 | 2315篇 |
2013年 | 2705篇 |
2012年 | 3947篇 |
2011年 | 3943篇 |
2010年 | 2254篇 |
2009年 | 1805篇 |
2008年 | 2777篇 |
2007年 | 2815篇 |
2006年 | 2647篇 |
2005年 | 2347篇 |
2004年 | 2183篇 |
2003年 | 1882篇 |
2002年 | 1656篇 |
2001年 | 965篇 |
2000年 | 914篇 |
1999年 | 789篇 |
1998年 | 327篇 |
1997年 | 262篇 |
1996年 | 271篇 |
1995年 | 233篇 |
1994年 | 193篇 |
1993年 | 153篇 |
1992年 | 421篇 |
1991年 | 395篇 |
1990年 | 414篇 |
1989年 | 386篇 |
1988年 | 331篇 |
1987年 | 302篇 |
1986年 | 285篇 |
1985年 | 275篇 |
1984年 | 215篇 |
1983年 | 167篇 |
1982年 | 100篇 |
1981年 | 103篇 |
1980年 | 89篇 |
1979年 | 141篇 |
1978年 | 94篇 |
1977年 | 105篇 |
1974年 | 86篇 |
1973年 | 80篇 |
1971年 | 76篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
A. Ríos A.I. López-Navas M.A. Ayala G. Garrido M.J. Sebastián J. Carrillo Á. Sánchez J. Flores-Medina J.J. Ruiz-Manzanera A.M. Hernández P. Ramírez P. Parrilla 《Transplantation proceedings》2019,51(2):258-260
The Latin American population has a double way of immigration, one toward the United States by proximity and another toward Spain by sociocultural affinity. This population increase is affecting organ donation and transplantation in receiving countries.
Objective
To analyze the brain death (BD) concept knowledge in the Dominican Republic immigrant population in Florida (United States) and Spain.Method
Population under study: Population born in the Dominican Republic, resident in Florida (United States) and in Spain. Inclusion criteria: Population older than 15 years stratified by age and sex. Assessment instrument: Donation attitude questionnaire PCID-DTO-Ríos. Fieldwork: Random selection based on stratification. Immigration support association collaboration in Florida and Spain was needed to locate potential respondents. Completion was anonymous and self-administered, with verbal consent.Results
A total of 123 respondents, 57 residents in Spain and 66 in Florida, have been included in the study. The 27% (n = 33) of the respondents knowledgeable of the BD concept consider it the death of an individual. Of the remainder, 52% (n = 64) do not know about it, and the remaining 21% (n = 26) believe it does not mean the death of a patient. No differences were observed regarding migration countries (P > .05). There was no association of the BD concept with other psychosocial factors analyzed or with the attitude toward organ donation.Conclusions
Knowledge of the BD concept among the Dominican immigrant population is similar in Spain and Florida, and, unlike most studies, there is no objective association with the attitude toward organ donation. 相似文献3.
4.
Pankaj Kumar Mishra 《European journal of cardio-thoracic surgery》2006,29(5):861-2; author reply 862
5.
6.
Palat Balachandran M.S. M.Ch. Shaleen Agarwal M.S. M.Ch. Narendra Krishnani M.D. Chandra M. Pandey Ph.D. Ashok Kumar M.S. M.Ch. Sadiq S. Sikora M.S. Rajan Saxena M.S. Vinay K. Kapoor M.S. 《Journal of gastrointestinal surgery》2006,10(6):848-854
The aim of this study was to examine the predictors of long-term survival (>24 months) in patients with gall bladder cancer.
A retrospective review of 117 cases of gall bladder cancer resected between 1989 and 2000. The resections included 80 simple
cholecystectomies and 37 extended procedures. Patients with survival >24 months (n=44) were compared with those having survival
<24 months (n=73) for 17 prognostic factors. Overall median survival was 16 months with a 5-year survival of 27%. T status
(P=.000) and adjuvant chemoradiotherapy (P=.001) were independent predictors of long-term survival. Survival advantage was
seen in T3N+ve disease (P=.007) with extended procedures. Complete (R0) resection was attained in 30 patients with a 5-year
survival advantage of 30% as compared with incomplete (R1) resection (P=.0002). Adjuvant chemoradiotherapy improved survival
in simple cholecystectomy group (P=.0008) but no advantage was seen after extended procedures. Stage III (P=.001) and node-positive
disease (P=.0005) had significant benefit with adjuvant therapy. Poor differentiation and vascular invasion were associated
with poor long-term survival. R0 resection was associated with prolonged survival. Extended procedures improved survival in
patients with T3N+ve disease. Addition of chemoradiotherapy made significant improvement in long-term survival in stage III
and node-positive lesions and in patients undergoing simple cholecystectomy. R0 resection predicted long-term survival in
gall bladder cancer. T3 N+ve disease had better survival after extended procedures. Adjuvant chemoradiotherapy improved survival
in stage III and node-positive disease. Poor differentiation and vascular invasion were adverse predictors of survival. 相似文献
7.
Surender Kumar Yachha Rakesh Aggarwal S Srinivas Anshu Srivastava Sanjay K Somani Srivenu Itha 《Indian journal of gastroenterology》2006,25(3):132-135
BACKGROUND: We prospectively evaluated the usefulness of IgA tissue transglutaminase antibodies (IgA tTG) in the initial diagnosis of celiac disease (CD) and compared its diagnostic potential with that of IgA anti-endomysial antibodies (IgA EMA) and anti-IgA and IgG gliadin antibodies (AGA and AGG, respectively). METHODS: Sera of 23 untreated children fulfilling the revised ESPGHAN criteria for diagnosis of CD (Group I; mean age 10.8 y); 19 disease controls (Group II; mean age 8.5 y) presenting with chronic diarrhea, short stature or both; and 22 healthy children (Group III; mean age 8.8 y) were studied. These were tested in a blinded manner for AGA, AGG, IgA tTG (guinea pig as antigen) and IgA EMA. RESULTS: In Group I, IgA EMA was positive in 19, IgA tTG in 17, AGA in 14 and AGG in 17 patients. In Group II, these tests were positive in 1, 0, 2 and 14 patients, respectively and in Group III, in 0, 0, 0 and 1 child, respectively. Analyzing data from Group I and II, IgA EMA, IgA tTG, AGA and AGG had sensitivity rates of 83%, 74%, 61% and 74%, respectively; the specificity rates were 95%, 100%, 89% and 26%; positive predictive values were 95%, 100%, 88% and 55% and negative predictive values were 82%, 74%, 65% and 45%, respectively. CONCLUSION: IgA tTG is useful for the diagnosis of CD, with sensitivity and specificity rates comparable to those of EMA and this test is well suited for use in tropical countries like India. 相似文献
8.
Adalberto Parra Jorge Ramírez-Peredo Rocío Hidalgo Amelia Morales-Toquero Gabriela Velásquez-Ramírez Alejandro Ruiz-Argüelles Guillermo J Ruiz-Argüelles 《Biology of blood and marrow transplantation》2006,12(5):566-572
We compared the functional status of the hypothalamic dopaminergic tone in patients given an allogeneic hematopoietic stem cell transplantation (allo-HSCT) with chronic graft-versus-host disease (GVHD) with that observed in patients with allo-HSCT without chronic GVHD and in healthy controls. The effect of acute dopaminergic blockade with intravenous metoclopramide on serum prolactin (PRL) concentrations was evaluated. Twenty volunteers, 20 to 52 years of age, seronegative for both hepatitis C virus and the human immunodeficiency virus, were studied: (1) 10 clinically healthy men (group 1), and (2) 9 patients with leukemia, and 1 patient with refractory aplastic anemia who underwent allo-HSCT, 5 of whom (3 men and 2 women) developed chronic GVHD (group 2), and 5 (3 men and 2 women) who did not develop chronic GVHD (group 3). Serum PRL concentrations were measured both fasting and after intravenous administration of metoclopramide (10-mg bolus). The area under the PRL curve was calculated. Patients in group 2 were older than those in groups 1 and 3 (P<.018), but their body mass index was similar. Fasting serum PRL concentrations were similar among the 3 groups; however, group 2 had higher PRL concentrations throughout the test (P<.001) and a greater area under the PRL curve than groups 1 and 3 (P<.001), without differences between the last 2 groups. The differences remained significant after adjustment for age (P<.01). Our results in a small group of patients with chronic GVHD after allo-HSCT suggest the existence of an increased functional level of their hypothalamic dopamine tone, which would favor a tendency toward a diminished endogenous production, release of pituitary PRL, or both. This could represent an adaptive mechanism aiming to maintain circulating PRL concentrations within a physiological range. 相似文献
9.
10.
Chromogenic ionophore-based methods for spectrophotometric assay of sodium and potassium in serum and plasma 总被引:1,自引:0,他引:1
A Kumar E Chapoteau B P Czech C R Gebauer M Z Chimenti O Raimondo 《Clinical chemistry》1988,34(9):1709-1712
We report spectrophotometric methods for quantifying sodium and potassium in serum and plasma without sample pretreatment or solvent-extraction steps. The methods are based on novel chromogenic ionophores characterized by molecular structures highly preorganized for binding, which result in exceptionally high sensitivity and selectivity (negligible responses to sodium at 80 to 200 mmol/L in the potassium assay and to potassium at 0 to 10 mmol/L in the sodium assay). The within-run imprecisions are comparable with those for ion-selective electrodes (for K, 1.0% at 4.5 mmol/L; for Na, 1.1% at 136 mmol/L); the analytical range is 2-10 mmol/L for potassium, 80-170 mmol/L for sodium. The results for greater than 100 patients' samples correlated well with results obtained with ion-selective electrodes (r = 0.99 for K, 0.97 for Na). The ready-to-use aqueous reagents will be available under the trade name of ChromoLyte for use with Technicon's RA family of clinical analyzers. 相似文献