全文获取类型
收费全文 | 4109篇 |
免费 | 172篇 |
国内免费 | 12篇 |
专业分类
耳鼻咽喉 | 18篇 |
儿科学 | 178篇 |
妇产科学 | 56篇 |
基础医学 | 505篇 |
口腔科学 | 81篇 |
临床医学 | 317篇 |
内科学 | 765篇 |
皮肤病学 | 74篇 |
神经病学 | 307篇 |
特种医学 | 115篇 |
外科学 | 561篇 |
综合类 | 98篇 |
一般理论 | 1篇 |
预防医学 | 238篇 |
眼科学 | 216篇 |
药学 | 473篇 |
中国医学 | 24篇 |
肿瘤学 | 266篇 |
出版年
2023年 | 36篇 |
2022年 | 99篇 |
2021年 | 164篇 |
2020年 | 87篇 |
2019年 | 94篇 |
2018年 | 126篇 |
2017年 | 82篇 |
2016年 | 113篇 |
2015年 | 127篇 |
2014年 | 145篇 |
2013年 | 187篇 |
2012年 | 301篇 |
2011年 | 299篇 |
2010年 | 160篇 |
2009年 | 135篇 |
2008年 | 207篇 |
2007年 | 226篇 |
2006年 | 200篇 |
2005年 | 172篇 |
2004年 | 155篇 |
2003年 | 138篇 |
2002年 | 146篇 |
2001年 | 121篇 |
2000年 | 104篇 |
1999年 | 74篇 |
1998年 | 31篇 |
1997年 | 28篇 |
1996年 | 43篇 |
1995年 | 16篇 |
1994年 | 6篇 |
1993年 | 12篇 |
1992年 | 31篇 |
1991年 | 32篇 |
1990年 | 39篇 |
1989年 | 45篇 |
1988年 | 40篇 |
1987年 | 36篇 |
1986年 | 29篇 |
1985年 | 29篇 |
1984年 | 25篇 |
1983年 | 22篇 |
1982年 | 15篇 |
1981年 | 11篇 |
1980年 | 14篇 |
1979年 | 24篇 |
1977年 | 13篇 |
1974年 | 9篇 |
1973年 | 6篇 |
1971年 | 7篇 |
1970年 | 9篇 |
排序方式: 共有4293条查询结果,搜索用时 15 毫秒
21.
Gm allotypes in blacks with systemic lupus erythematosus 总被引:3,自引:0,他引:3
J A Fedrick J P Pandey Z Chen H H Fudenberg S K Ainsworth R L Dobson 《Human immunology》1983,8(2):177-181
Serum samples were collected from 328 healthy American Blacks and from 61 American Blacks with systemic lupus erythematosus (SLE). Sera were typed for the Gm1,2,3,5,6,13,17, and 21 allotypes as well as for the Km(1) allotype. The frequency of Gm phenotype 1,17;5,6,13 was significantly increased in the SLE patients (p = 0.0001, RR = 3.19, EF = 0.29). Our data suggest the existence of at least two immunoglobulin allotype associated genes that somehow interact to increase susceptibility to SLE in Blacks. To our knowledge, this is the first report of an association of Gm and SLE in Blacks. 相似文献
22.
23.
The effects of several antidepressants on the release of (3H)-norepinephrine (NE) from homogenates of rat cerebral cortex were studied. A continuous superfusion collection system was used in order to differentiate these effects from effects on reuptake. Amitriptyline, maprotiline, mianserin, and trazodone produced a statistically significant decrease in spontaneous tritium efflux when present in the superfusion medium at a concentration of 1.0 M. The other antidepressants studied had no effect. We used a buffer with the K+ concentration raised to 56 mM as a model of depolarization-induced release. Desipramine, fluoxetine, and iprindole (again at 1.0 M) caused a significant decrease in this measure. These results indicate that some of both the tricyclic and atypical antidepressants may alter spontaneous or depolarization-induced release of NE.This work was supported in part by a grant from the Pharmaceutical Manufactures Association Foundation-Medical Student Research Fellowship 相似文献
24.
Burkhard Tönshoff Helio Tedesco-Silva Robert Ettenger Martin Christian Anna Bjerre Luca Dello Strologo Stephen D. Marks Lars Pape Udaykiran Veldandi Patricia Lopez Marc Cousin Priti Pandey Matthias Meier 《American journal of transplantation》2021,21(1):123-137
CRADLE was a 36-month multicenter study in pediatric (≥1 to <18 years) kidney transplant recipients randomized at 4 to 6 weeks posttransplant to receive everolimus + reduced-exposure tacrolimus (EVR + rTAC; n = 52) with corticosteroid withdrawal at 6-month posttransplant or continue mycophenolate mofetil + standard-exposure TAC (MMF + sTAC; n = 54) with corticosteroids. The incidence of composite efficacy failure (biopsy-proven acute rejection [BPAR], graft loss, or death) at month 36 was 9.8% vs 9.6% (difference: 0.2%; 80% confidence interval: −7.3 to 7.7) for EVR + rTAC and MMF + sTAC, respectively, which was driven by BPARs. Graft loss was low (2.1% vs 3.8%) with no deaths. Mean estimated glomerular filtration rate at month 36 was comparable between groups (68.1 vs 67.3 mL/min/1.73 m2). Mean changes (z-score) in height (0.72 vs 0.39; P = .158) and weight (0.61 vs 0.82; P = .453) from randomization to month 36 were comparable, whereas growth in prepubertal patients on EVR + rTAC was better (P = .050) vs MMF + sTAC. The overall incidence of adverse events (AEs) and serious AEs was comparable between groups. Rejection was the leading AE for study drug discontinuation in the EVR + rTAC group. In conclusion, though AE-related study drug discontinuation was higher, an EVR + rTAC regimen represents an alternative treatment option that enables withdrawal of steroids as well as reduction of CNIs for pediatric kidney transplant recipients. ClinicalTrials.gov: NCT01544491. 相似文献
25.
This issue reports selected results from a comprehensive study of infant and child mortality based on the National Family Health Survey data. The analysis distinguishes between neonatal, postneonatal, infant and child mortality since mortality and its causes vary considerably among children of different ages. Hazard regression analysis was used to estimate the effects of each individual variable as the factors that affect infant and child mortality tend to be correlated with each other. The study involves adjusted effects of selected socioeconomic and demographic characteristics on neonatal, postneonatal, infant, and child mortality for children born during the survey. Short birth intervals have a great effect on infant and child mortality. A previous birth interval of less than 24 months increases child mortality by about 67%. Neonatal mortality is highest among children of very young mothers. Child mortality is higher for girls in all states except Tamil Nadu, Kerala, and Goa. Seven groups of children who are especially vulnerable to infant and child mortality were identified. Thus, intervention programs, such as efforts to provide supplemental nutrition and basic immunization to pregnant mothers, infants and young children need to focus on these high-risk groups. Results for many states show elevated mortality rates for girls after the neonatal period. Family health programs aimed at overall improvement in mortality levels should pay attention to providing basic health care and supplemental nutrition to girls. 相似文献
26.
S K Kabra Y Jain R M Pandey T MadhulikaSinghal P Tripathi S Broor P Seth V Seth 《Transactions of the Royal Society of Tropical Medicine and Hygiene》1999,93(3):294-298
An epidemic of dengue haemorrhagic fever (DHF) occurred in Delhi in 1996. A total of 240 children between the age of 4 months to 13 years of either sex, admitted in one hospital, were evaluated. Two hundred and sixteen (90%) children were from Delhi. A clinical diagnosis of dengue fever (DF) was made in 25 (10%), dengue fever with unusual bleeding (DFB) in 22 (9%), DHF in 80 (33%) and dengue shock syndrome (DSS) in 113 (47%) of the children strictly according to the WHO classification. The age peaked at 8 years. There was no association between various grades of severity of illness and age-groups though girls suffered from more severe illness. No association between severity of malnutrition and severity of illness was observed. Tourniquet test was positive in 40% with DF, 18% with DFB, 62% with DHF and 64% with DSS. In DSS haematemesis was present in 55 (49%), epistaxis in 39 (35%), melaena in 27 (24%) and ecchymosis in 34 (30%) patients. Children diagnosed as DFB had haematemesis and epistaxis in 12 (55%) and 10 (45%) respectively. Intravenous fluid requirement was clearly less in DFB patients than in DHF/DSS patients. Unusual clinical features in the form of jaundice were present in 7 (6%), hepatic encephalopathy in 6 (5%) and dengue encephalopathy in 6 (5%) patients. Dengue 2 virus was isolated from 10 of the 50 patients for whom viral culture was done on C6/36 clone of Aedes albopictus cell line. Eighteen patients suffering from DSS died giving an overall case fatality of 7.5%. The mortality rate in DHF/DSS was 9.3%. It is further suggested that DFB is a distinct entity. Most patients could be classified by the WHO classification if a retrospective packed cell volume was used to assess haemoconcentration. We suggest that development of area-specific criteria for diagnosis and management is desirable. 相似文献
27.
Parker JD Thiessen JJ Reilly R Tong JH Stewart DJ Pandey AS 《The Journal of pharmacology and experimental therapeutics》1999,289(1):261-265
Levels of endothelin-1 (ET-1) are elevated in many disease states, although its total body kinetics of elimination are poorly understood. Therefore, it remains uncertain whether the presence of elevated levels of ET-1 in the setting of disease are secondary to changes in production or clearance or some combination thereof. Using a 125I-labeled ET-1 infusion technique, the volume of distribution and kinetics of clearance of endothelin were described in five normal volunteers. Heart rate, blood pressure, right atrial pressure, and arterial blood samples for the counting of 125I and the measurement of ET-1 were obtained at multiple time points before and up to 45 h after the start of the infusion. The radiotracer infusion had no effect on heart rate, blood pressure, right atrial pressure, or endogenous ET-1 levels. ET-1 clearance was best described by a three-compartment model, which revealed that ET-1 has a much longer terminal half-life and volume of distribution than was previously reported. This suggests extensive uptake of ET-1 in various organ systems and slow clearance. These new findings have important implications for the understanding of the pathophysiology of ET-1 in disease states as well as for the understanding and development of ET-1 receptor blockers and endothelin-converting enzyme inhibitors. 相似文献
28.
29.
Barrett JS Hochadel TJ Morales RJ Rohatagi S DeWitt KE Watson SK DiSanto AR 《American journal of therapeutics》1996,3(10):688-698
This open-label, two-phase cross-over study compared the safety and pharmacokinetics of transdermally administered selegiline and orally administered selegiline hydrochloride in elderly men and women (n = 6/gender). Single oral doses of 10 mg selegiline hydrochloride and single 1/2 and 1 selegiline transdermal system (STS) (delivering similar3.4 and 6.3 mg over 24 h) administered topically were safe and well tolerated in all subjects. Plasma concentrations of selegiline (SEL) and its N-desmethylselegiline (DMS), L-amphetamine (AMP), and L-methamphetamine (MET) metabolites were measured using an HPLC/MS/MS method with lower quantitation limits of 10, 50, 200, and 200 pg/mL, respectively. No significant gender-related differences were observed following single 10-mg oral doses of selegiline hydrochloride or single 24-h applications of 1/2 and 1 STS to elderly males and females. The low level of dermal irritation as assessed by erythema and edema rating scales suggests that the STS was similar to Band-Aid (Johnson & Johnson, Skillman, NJ) controls. The transdermal administration of SEL bypasses the first-pass metabolism, that is significant after oral administration (first-pass extraction >90%). Peak plasma levels of 1.19, 23.22, 4.78, and 14.08 ng/mL were observed for SEL, DMS, AMP, and MET after a single 10-mg oral dose to the elderly. By contrast, peak plasma levels of 2.10, 0.85, 1.06, and 2.71 ng/mL were observed for SEL, DMS, AMP, and MET after a single 24-h application of 1 STS. Comparison of dose-corrected areas under the curve (AUCs) (made under the assumption of linear pharmacokinetics) indicate the SEL exposure after transdermal application was more than 50-fold greater than that obtained orally. This increase in systemic SEL exposure at the expense of metabolite formation that is reduced to <70% of that obtained orally for N-DMS, L-AMP, and L-MET is hypothesized to be of therapeutic value in patients with a variety of neurodegenerative and psychiatric disorders. 相似文献
30.