全文获取类型
收费全文 | 1455篇 |
免费 | 134篇 |
国内免费 | 2篇 |
专业分类
耳鼻咽喉 | 15篇 |
儿科学 | 75篇 |
妇产科学 | 11篇 |
基础医学 | 250篇 |
口腔科学 | 20篇 |
临床医学 | 191篇 |
内科学 | 336篇 |
皮肤病学 | 22篇 |
神经病学 | 99篇 |
特种医学 | 91篇 |
外科学 | 154篇 |
综合类 | 17篇 |
一般理论 | 2篇 |
预防医学 | 97篇 |
眼科学 | 8篇 |
药学 | 119篇 |
肿瘤学 | 84篇 |
出版年
2021年 | 17篇 |
2019年 | 21篇 |
2018年 | 15篇 |
2017年 | 8篇 |
2016年 | 15篇 |
2015年 | 22篇 |
2014年 | 19篇 |
2013年 | 40篇 |
2012年 | 49篇 |
2011年 | 49篇 |
2010年 | 26篇 |
2009年 | 23篇 |
2008年 | 58篇 |
2007年 | 52篇 |
2006年 | 57篇 |
2005年 | 41篇 |
2004年 | 54篇 |
2003年 | 50篇 |
2002年 | 51篇 |
2001年 | 40篇 |
2000年 | 58篇 |
1999年 | 37篇 |
1998年 | 28篇 |
1997年 | 25篇 |
1996年 | 23篇 |
1995年 | 26篇 |
1994年 | 20篇 |
1993年 | 20篇 |
1992年 | 47篇 |
1991年 | 50篇 |
1990年 | 44篇 |
1989年 | 44篇 |
1988年 | 46篇 |
1987年 | 46篇 |
1986年 | 40篇 |
1985年 | 41篇 |
1984年 | 38篇 |
1983年 | 19篇 |
1982年 | 22篇 |
1981年 | 20篇 |
1980年 | 8篇 |
1979年 | 17篇 |
1978年 | 16篇 |
1977年 | 12篇 |
1976年 | 16篇 |
1975年 | 11篇 |
1974年 | 14篇 |
1973年 | 14篇 |
1968年 | 11篇 |
1967年 | 11篇 |
排序方式: 共有1591条查询结果,搜索用时 0 毫秒
1.
This study examined the immunoregulatory role of recombinant interleukin 4 (IL-4), also known as B-cell stimulating factor 1, on the generation of cytotoxic effector cells from normal and leukaemic human blood mononuclear cells. When tested on cells from normal individuals, the addition of IL-4 to mixed lymphocyte cultures led to a dose-dependent proliferation of T-helper cells (CD3, 4 positive) with a concomitant decrease in phenotypic and functional cytotoxic T cells and natural killer (NK) cells. IL-4 also inhibited the interleukin-2 (IL-2)-induced generation of lymphokine-activated killer (LAK) activity when added at the beginning of mixed lymphocyte culture. When tested on mature leukaemic NK cells, IL-4 also inhibited the ability of IL-2 to induce LAK function using a short-term culture system. These results show that IL-4 acts on both normal and leukaemic cells and suggests that it acts at more than one level during the development of LAK function. 相似文献
2.
A digital test of pelvic muscle strength for evaluation of a pelvic muscle exercise (PME) program was developed with a sample of 338 incontinent women living at home. Factors of perceived pressure, alteration of the vertical plane, and time were combined to form a 7-point scale ranging from 0 to 4. Test-retest for the anteroposterior score was r = .65, p less than .01 with interrater reliability, r = .91, p less than .01. Relationship to other variables and further development of the measure are discussed. 相似文献
3.
A L Whall G L Gillis D Yankou D E Booth C A Beel-Bates 《Journal of gerontological nursing》1992,18(10):13-17
A significant number of nursing home residents exhibit behavior disturbances that are disruptive to the living and working environment in the nursing home. The most common disruptive behaviors cited by licensed nursing personnel included hitting/slapping, verbally aggressive remarks, screaming, pacing, wandering, and repetitive verbal requests. Self-injurious behavior, property destruction, and hiding things were not mentioned. Many of the nursing strategies listed by nursing staff as being used to alleviate disruptive behaviors are traditional care activities, eg, talking to and counseling patients, touching, or altering care. However, chemical and physical restraints were also frequently listed. 相似文献
4.
Sequential contrast-enhanced MR imaging of the penis 总被引:1,自引:0,他引:1
5.
A R Vadiee E J Shannon T P Gillis R N Mshana R C Hastings 《International journal of leprosy and other mycobacterial diseases : official organ of the International Leprosy Association》1988,56(3):422-427
The kinetics of antibody responses of Mycobacterium leprae-infected armadillos to phenolic glycolipid-I (PGL-I) were studied by means of ELISA. The levels of both IgG and IgM antibodies to PGL-I increased with time. Some animals were less susceptible to disseminations of M. leprae infection and lived longer than others. These animals had high absorbance values (greater than 0.7) for IgG anti-PGL-I compared to more susceptible armadillos that had lower absorbance values for IgG anti-PGL-I. 相似文献
6.
P J Gatti K J Hill A M Da Silva W P Norman R A Gillis 《The Journal of pharmacology and experimental therapeutics》1988,245(1):373-380
The purpose of our study was to determine whether clonidine exerts its centrally mediated hypotensive action at three sites that influence arterial pressure located in the medulla, specifically associated with the intermediate area of the ventrolateral medulla. The "intermediate area" lies approximately 1.5 mm caudal to the border of the trapezoid body (caudal border) and 4 mm lateral to the midline. One of the sites that influence arterial pressure lies in the nucleus reticularis rostroventrolateralis. The second site lies in close proximity to the rostral part of the nucleus reticularis lateralis (rLRN) and also near the A1 area. The third site lies in the most rostral area and medial to the nucleus reticularis rostroventrolateralis, that is in the nucleus paragigantocellularis lateralis. Unilateral microinjections of 0.22 and 0.43 nmol of clonidine into the rLRN produced dose-dependent decreases in arterial pressure. The 0.43 nmol dose of clonidine had no effect when unilaterally or bilaterally microinjected into either the nucleus reticularis rostroventrolateralis or into the nucleus paragigantocellularis lateralis. Microinjection of the alpha-2 adrenoceptor antagonist, idazoxan (16.6 nmol), unilaterally into rLRN had no effect per se, but prevented the hypotensive effect of a subsequent microinjection of clonidine. Similarly, bilateral microinjection of idazoxan into rLRN counteracted the hypotensive effect of i.v. administered clonidine. These data indicate that clonidine acts at alpha-2 adrenoceptors in the rLRN to produce hypotension. 相似文献
7.
We report on a child with giant congenital aortic aneurysm, sternal defect, hemangiomas of face, supraumbilical raphé, and review the only two other cases reported to date. Congenital aortic aneurysm is an ominous malformation that has to be systematically searched in children with the sternal malformation/vascular dysplasia complex. 相似文献
8.
Ethanol fixation of sputum sediments for DNA-based detection of Mycobacterium tuberculosis. 下载免费PDF全文
The effect of ethanol fixation on PCR detection and viability of Mycobacterium tuberculosis in human sputum sediments was evaluated. M. tuberculosis seeded into sputum sediments was efficiently killed when treated for 1 h with 50, 70, or 95% ethanol. PCR amplification of a 123-bp fragment of the M. tuberculosis-specific IS6110 was not affected in ethanol-treated samples even when fixation was extended to 24 h. Ethanol fixation of sputum sediments did not affect the PCR detection of M. tuberculosis in clinical samples. PCR results from ethanol-treated clinical samples containing M. tuberculosis (smear positive and smear negative) or other respiratory pathogens correlated directly with the results by conventional detection methods for M. tuberculosis. Our results show that ethanol fixation of human sputum sediments containing M. tuberculosis significantly reduces the potential exposure of workers to viable M. tuberculosis without affecting DNA analysis by PCR. Also, ethanol fixation of sputum sediments provides a simple and inexpensive way to store and transport clinical specimens identified for DNA-based diagnostics without refrigeration. 相似文献
9.
10.
Competitive, enzyme-linked immunosorbent assay for toxic shock syndrome toxin 1. 总被引:5,自引:7,他引:5 下载免费PDF全文
We developed a competitive, enzyme-linked immunosorbent assay for the quantitation of toxic shock syndrome toxin 1 (TSST-1). Polyvalent immunoglobulin G from immunized rabbits was used as the capture antibody, and alkaline phosphatase conjugated to purified toxin served as the indicator enzyme. A standard curve was generated with each experiment, from which the concentration of toxin in culture supernatants was extrapolated. The assay was useful for determining toxin concentrations of 0.03 to 0.5 micrograms/ml, which is a substantial, practical improvement over immunodiffusion methods. Staphylococcal enterotoxins A through E were not significantly cross-reactive in the assay, and staphylococcal protein A did not interfere with quantitation of TSST-1. By testing a variety of staphylococcal strains, we found 100% concordance between toxin determinations made with our assay and those made by the investigators from whom the strains were obtained. The competitive, enzyme-linked immunosorbent assay is a highly reproducible, inexpensive means of determining TSST-1 concentrations and may have broad applicability in the field of toxic shock research. 相似文献