全文获取类型
收费全文 | 1115082篇 |
免费 | 76148篇 |
国内免费 | 1431篇 |
专业分类
耳鼻咽喉 | 15354篇 |
儿科学 | 35775篇 |
妇产科学 | 29429篇 |
基础医学 | 158924篇 |
口腔科学 | 30628篇 |
临床医学 | 100014篇 |
内科学 | 211376篇 |
皮肤病学 | 24994篇 |
神经病学 | 84681篇 |
特种医学 | 44558篇 |
外国民族医学 | 202篇 |
外科学 | 168455篇 |
综合类 | 22733篇 |
现状与发展 | 1篇 |
一般理论 | 288篇 |
预防医学 | 79420篇 |
眼科学 | 25406篇 |
药学 | 89504篇 |
7篇 | |
中国医学 | 2872篇 |
肿瘤学 | 68040篇 |
出版年
2019年 | 8364篇 |
2018年 | 11964篇 |
2017年 | 9386篇 |
2016年 | 10641篇 |
2015年 | 11892篇 |
2014年 | 16117篇 |
2013年 | 23466篇 |
2012年 | 32349篇 |
2011年 | 34105篇 |
2010年 | 19992篇 |
2009年 | 18838篇 |
2008年 | 31666篇 |
2007年 | 33924篇 |
2006年 | 34519篇 |
2005年 | 32813篇 |
2004年 | 31378篇 |
2003年 | 30138篇 |
2002年 | 29052篇 |
2001年 | 61203篇 |
2000年 | 62606篇 |
1999年 | 52087篇 |
1998年 | 12964篇 |
1997年 | 11417篇 |
1996年 | 11420篇 |
1995年 | 10739篇 |
1994年 | 9740篇 |
1993年 | 9269篇 |
1992年 | 38774篇 |
1991年 | 37233篇 |
1990年 | 36635篇 |
1989年 | 35158篇 |
1988年 | 31670篇 |
1987年 | 30785篇 |
1986年 | 29032篇 |
1985年 | 27211篇 |
1984年 | 19848篇 |
1983年 | 16664篇 |
1982年 | 9201篇 |
1979年 | 17547篇 |
1978年 | 11835篇 |
1977年 | 10576篇 |
1976年 | 9193篇 |
1975年 | 10388篇 |
1974年 | 12032篇 |
1973年 | 11636篇 |
1972年 | 11102篇 |
1971年 | 10420篇 |
1970年 | 9542篇 |
1969年 | 9256篇 |
1968年 | 8191篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
991.
992.
Serum level of sex hormone-binding globulin (SHBG) was measured by immunoradiometric assay in fifty two breast cancer patients and twenty nine healthy female volunteers. The results are as follows: 1) Although the serum SHBG concentration showed no significant difference between the breast cancer group and the healthy control group, the serum SHBG concentration in postmenopause was significantly higher in the breast cancer group (63.8 +/- 31.2nmol/ml/ml; mean +/- S.D.) than in the healthy control group (40.1 +/- 15.4nmol/ml). 2) Subsequently in the postmenopausal breast cancer group, the serum SHBG concentration was significantly higher in the estrogen receptor (ER)-negative cancer group (97.8 +/- 12.7nmol/ml) than in the ER-positive cancer group (55.8 +/- 32.1nol/ml). 3) No significant relationships were showed between the serum SHBG concentration and obesity or serum estradiol concentration in postmenopausal patients. 4) The serum SHBG concentration showed significant decrease 3 months after radical operation for breast cancer in postmenopausal patients. These results suggest the possibility of the SHBG synthesis in breast cancer tissue. 相似文献
993.
994.
Production of interleukin-1 by glomerular macrophages in nephrotoxic serum nephritis 总被引:1,自引:0,他引:1
K Matsumoto 《American journal of nephrology》1990,10(6):502-506
995.
K Suzuki Y Ichinose K Hashimoto K Matsumoto T Suzuki K Imai H Yamanaka 《Hinyokika kiyo. Acta urologica Japonica》1990,36(5):557-560
Transrectal ultrasonotomography is useful in following patients with benign prostatic hypertrophy, because prostatic shape and weight are precisely assumed. We studied the effect of chlormadinone acetate (CMA) on benign prostatic hypertrophy. CMA (50 mg/day) was administered to 30 patients with benign prostatic hypertrophy. Weight reduction over 10% of the gland was noticed in 24 cases (80%). Mictional conditions were improved in 70% subjectively and in 71.4% objectively. However, the number of nocturia decreased in only 18.9%. Reduction rate of the weight was unrelated with the weight of prostate before administration of CMA. Duration of administration of CMA and the reduction rate were estimated. There was no definite difference in reduction rate for the first 15 months, but there was a slightly high reduction rate after administration of CMA for more than 24 months. In 3 cases, the shape and weight of prostate were studied after discontinuation of CMA. The size of prostate showed a tendency to increase gradually. 相似文献
996.
K Ohtsuka K Tsuji Y Nakagawa H Ueda O Ozawa T Uchida T Ichikawa 《Journal of nutritional science and vitaminology》1990,36(3):265-276
O-beta-D-Galactopyranosyl-(1----4)-O-beta-D-galactopyranosyl-(1----4)-D- glucopyranose (designated as 4'GL) is produced from lactose by Cryptococcus laurentii. The influence of chronic ingestion of 4'GL on body weight gain, organ weight, serum lipids, and liver lipids was investigated in rats. The body weight gains of the 5% and 10% 4'GL-diet groups were higher than that of the control group. Food intake and fecal dry weight were significantly increased (p less than 0.05) by 4'GL feeding. The 4'GL diet produced a significant increase (p less than 0.01) in the wet weight and contents of both the cecum and the colon. However, no significant increase was observed in the weight of the stomach, small intestine, liver, or other organs. The effects of 4'GL on serum and liver lipid levels were not observed in this experiment. The digestion of 4'GL was measured in vitro using the artificial gastric juice, alpha-amylase of human saliva, alpha-amylase of hog pancreas, and mucosa of rat intestine. 4'GL was not hydrolyzed by these enzymes. Long-term ingestion of 4'GL did not cause any induction of 4'GL hydrolyzing enzyme activity in the rat small intestine. 相似文献
997.
998.
F Salomon R K?rprich J Biscoping J Strobel 《Klinische Monatsbl?tter für Augenheilkunde》1990,196(1):26-29
Local anesthetics injected retrobulbarly are detectable in the aqueous humor. From 40 patients who received a total dose of 140 mg lidocaine, 15 mg bupivacaine, and 30 mg etidocaine, samples of aqueous humor were taken between 30 and 90 minutes after administration (average 57 minutes). The mean lidocaine concentration was 1.02 micrograms/ml, that of bupivacaine 0.075 micrograms/ml. Etidocaine, used only for facial nerve block in front of the ear, could not be detected in the aqueous humor. All three substances were found in the central venous blood. It therefore appears unlikely that any of them are transported via the blood-aqueous barrier, whether actively or passively. Local anesthetics can inhibit corneal cell proliferation and result in lens opacification when administered into the conjunctival sac. It may be that local anesthetics detected in the aqueous humor have similar effects resulting from contact with the cornea and lens. 相似文献
999.
A new method of refractive corneal surgery is presented. With the q-switched Nd:YAG-laser Visulas (Zeiss-Oberkochen) we succeed in altering the optical power of the cornea of rabbits, pigs and humans. The number of applied laser spots and the distribution pattern influence the way and the amount of change of refraction. The method, clinical and histological features, complications and prospects of the Nd: YAG laser keratorhexis are described. 相似文献
1000.
Lifetime toxicity/carcinogenicity studies of FD & C Blue No. 1 (brilliant blue FCF) in rats and mice
FD & C Blue No. 1 was fed to Charles River CD rats and CD-1 mice as a dietary admixture in lifetime toxicity/carcinogenicity studies. The rat study was conducted with an in utero phase in which the compound was administered to the F0 generation rats (60/sex/group) at dietary concentrations of 0.0%, 0.0%, 0.1%, 1.0% or 2.0%. After randomly selecting the F1 animals, the lifetime phase was initiated at the same levels with 70 rats/sex/group, including two control groups. The maximum exposure times were 116 and 111 wk for males and females, respectively. The no-observed-adverse-effect levels are dietary concentrations of 2.0% for males (1072 mg/kg body weight/day), and 1.0% for females (631 mg/kg/day) based on a 15.0% decrease in terminal body weight and decreased survival in the high-dose females compared with the combined control groups. Charles River CD-1 mice (60/sex/group) were fed FD & C Blue No. 1 as a dietary admixture at levels of 0.0%, 0.0%, 0.5%, 1.5% or 5.0% in a lifetime toxicity/carcinogenicity study. The maximum exposure time was 104 wk for both males and females. No consistent, significant compound-related adverse effects were noted. The no-observed-adverse-effect level established in this study is a dietary concentration of 5.0% (7354 mg/kg/day and 8966 mg/kg/day for male and female mice, respectively. 相似文献