全文获取类型
收费全文 | 2264509篇 |
免费 | 168696篇 |
国内免费 | 7405篇 |
专业分类
耳鼻咽喉 | 30370篇 |
儿科学 | 72408篇 |
妇产科学 | 60946篇 |
基础医学 | 314732篇 |
口腔科学 | 63634篇 |
临床医学 | 203739篇 |
内科学 | 448173篇 |
皮肤病学 | 53212篇 |
神经病学 | 181686篇 |
特种医学 | 92299篇 |
外国民族医学 | 472篇 |
外科学 | 349072篇 |
综合类 | 49512篇 |
现状与发展 | 3篇 |
一般理论 | 686篇 |
预防医学 | 171726篇 |
眼科学 | 49738篇 |
药学 | 167979篇 |
10篇 | |
中国医学 | 4585篇 |
肿瘤学 | 125628篇 |
出版年
2018年 | 23410篇 |
2017年 | 18614篇 |
2016年 | 22001篇 |
2015年 | 24135篇 |
2014年 | 33182篇 |
2013年 | 49752篇 |
2012年 | 63467篇 |
2011年 | 68088篇 |
2010年 | 41297篇 |
2009年 | 39331篇 |
2008年 | 63646篇 |
2007年 | 67938篇 |
2006年 | 69209篇 |
2005年 | 66411篇 |
2004年 | 63624篇 |
2003年 | 61834篇 |
2002年 | 59324篇 |
2001年 | 113817篇 |
2000年 | 117527篇 |
1999年 | 97588篇 |
1998年 | 27199篇 |
1997年 | 24211篇 |
1996年 | 24887篇 |
1995年 | 24446篇 |
1994年 | 22629篇 |
1993年 | 21334篇 |
1992年 | 77343篇 |
1991年 | 74963篇 |
1990年 | 72768篇 |
1989年 | 69913篇 |
1988年 | 64029篇 |
1987年 | 62747篇 |
1986年 | 59167篇 |
1985年 | 56603篇 |
1984年 | 42283篇 |
1983年 | 35556篇 |
1982年 | 21232篇 |
1981年 | 18801篇 |
1980年 | 17785篇 |
1979年 | 37975篇 |
1978年 | 26714篇 |
1977年 | 23128篇 |
1976年 | 20789篇 |
1975年 | 22424篇 |
1974年 | 26198篇 |
1973年 | 25202篇 |
1972年 | 23547篇 |
1971年 | 21890篇 |
1970年 | 20054篇 |
1969年 | 19047篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
961.
M K Song W Y Shin N F Adham N V Costea 《The American journal of clinical nutrition》1989,49(4):701-707
The effects of different amounts of dietary zinc on the Zn absorption rate and on Zn, calcium and magnesium concentrations in tissues of MOPC 104E tumor-bearing Balb/c mice were determined. The Zn absorption rate was inversely related to the amounts of Zn in their diets and was lower than that of nontumor-bearing control mice fed a laboratory mice chow. Zn concentrations of tumor-bearing mice were also low compared with control mice but tumor Zn concentrations, regardless of the concentrations of Zn in the diets, were higher than those of normal tissues of the host other than the pancreas. Ca concentrations in tumor and tissues of tumor-bearing mice were higher than in control animals but Mg concentrations in tissues of tumor-bearing mice appeared to be similar to those of control mice. Results suggest that tumor-bearing mice have a lower intestinal Zn absorption capacity and a higher Zn uptake rate causing other tissues to become hypozincemic and hypercalcemic. 相似文献
962.
963.
Dihydroxyacetone (DHA), a browning agent, protects photosensitive rats and humans against long ultraviolet radiation (UVA, 320-400 nm) and visible (blue) light. The photoprotective efficacy of DHA and structurally similar compounds was assessed as prevention of edema in the paws of psoralen-sensitized rats, after exposure to blacklight fluorescent lamps. Methylglyoxal produced a yellow-brown color and provided nearly the same protection as DHA, whereas monohydroxyacetone did not color the skin and afforded little or no protection. Glyceraldehyde provided a moderate amount of protection, which was enhanced by prior exposure of the agent to alkaline pH. A solution of 5-hydroxymethylfurfuraldehyde was yellow and provided minimal protection by staining the skin rather than browning it. We conclude that the ability to produce a brown color in skin is a useful criterion for screening compounds for photoprotective efficacy against UVA radiation. 相似文献
964.
A clinical phase I study for T-2588 was carried out in 25 healthy male volunteers. Each volunteer received T-2588 in one of the following doses: 100 mg capsule or tablet as a single oral administration in fasting or non-fasting state, 200 or 400 mg capsule as a single oral administration in non-fasting state or 300 or 600 mg daily for 14 approximately 15 days as a repeated administration in non-fasting state. The results are summarized below. No subjective or objective adverse effects were noted after a single oral administration. But repeated dose of 300 mg daily for 15 days and 600 mg daily for 14 days brought about abdominal distension in 1 case and soft stool in 1 case, respectively. As an abnormal change in clinical laboratory findings, 1 case with slight increase in transaminase after a single administration and 3 cases with slight increases in transaminase after repeated doses were observed. Time to reach a maximum concentration of T-2525 in blood (Tmax) was longer in subjects at non-fasting states than subjects in fasting states. Maximum blood concentration was lower in the latter than in the former. Urinary excretion rate in 8 hours after an oral administration was 19 approximately 28% and it was higher in non-fasting subject than in fasting subject. No accumulation of T-2588 was noted after repeated doses. 相似文献
965.
966.
H Nakagawa M Kikuhara M Sato K Sakai S Kimura 《Gan to kagaku ryoho. Cancer & chemotherapy》1987,14(9):2767-2770
A 50-year-old woman with bilateral inflammatory breast cancer (T4, N1b, M1, Stage IV) underwent right extended radical mastectomy and left modified radical mastectomy following pre-operative administration of carcinostatics (ADM, 5-FU) and irradiation. However, tumor recurrence was observed at the skin and right pleural cavity after the operation. Adriamycin-containing combination chemotherapy and radiation therapy were performed, but no significant response was obtained. CDDP was then administered intravenously at a daily dose of 62.5 mg/m2 at intervals of 60 days. The pleural effusion disappeared and the extent of skin metastasis was reduced, resulting in partial response which lasted for 90 days. The serum CEA level decreased from 13.1 ng/ml to 2.3 ng/ml. As the side effects of this therapy, slight nausea, vomiting and general fatigue were observed. This result suggested that CDDP is an effective drug for inflammatory breast cancer. 相似文献
967.
Platelet antibodies in systemic lupus erythematosus 总被引:2,自引:0,他引:2
C. Kaplan P. Champeix D. Blanchard J. Y. Muller J. P. Cartron 《British journal of haematology》1987,67(1):89-93
In systemic lupus erythematosus (SLE), the precise cause of the thrombocytopenia is unknown. Since platelet associated IgG is increased in many patients, it has been suggested that the destruction of platelets might be dependent on specific antibodies. In nine patients with SLE, platelet associated immunoglobulins were found together with free serum antibody which bound to platelets from all normal subjects. Using an immunoblotting technique with membrane proteins from normal platelets incubated with patient sera, target antigens were localized on a band of mol wt 108,000 in two cases (B. and N.) and on a band of mol wt 66,000 in a third (M.). When the same technique was applied to autologous platelets of patient N., autoantibody binding to the protein of mol wt 108,000 was demonstrated. The antigenic determinants were not removed from the platelets by enzyme treatment or by disulphide bond reduction, and were localized in the cytoplasmic fraction of the platelets. 相似文献
968.
969.
This research was designed to test the extent to which health education and health services administration students' perceptions of their roles as professionals matched the expectations of professional faculty. These perceptions were found to match in general. However, doubt was cast on the extent to which internships or practicums contributed to this result, since there was no change in student responses between the beginning of the junior year and end of the senior year, a period which includes fieldwork and most of the professional coursework presumed to influence professional development. Additional research is required to test this result with other student populations in other health professions and identify the point at which professional role and task definitions are amenable to change. 相似文献
970.