全文获取类型
收费全文 | 16223篇 |
免费 | 841篇 |
国内免费 | 90篇 |
专业分类
耳鼻咽喉 | 107篇 |
儿科学 | 266篇 |
妇产科学 | 239篇 |
基础医学 | 1893篇 |
口腔科学 | 402篇 |
临床医学 | 1071篇 |
内科学 | 4195篇 |
皮肤病学 | 223篇 |
神经病学 | 1064篇 |
特种医学 | 750篇 |
外科学 | 2930篇 |
综合类 | 63篇 |
预防医学 | 365篇 |
眼科学 | 288篇 |
药学 | 1225篇 |
中国医学 | 28篇 |
肿瘤学 | 2045篇 |
出版年
2023年 | 112篇 |
2022年 | 261篇 |
2021年 | 397篇 |
2020年 | 195篇 |
2019年 | 271篇 |
2018年 | 339篇 |
2017年 | 310篇 |
2016年 | 373篇 |
2015年 | 352篇 |
2014年 | 444篇 |
2013年 | 563篇 |
2012年 | 831篇 |
2011年 | 986篇 |
2010年 | 508篇 |
2009年 | 442篇 |
2008年 | 829篇 |
2007年 | 829篇 |
2006年 | 806篇 |
2005年 | 751篇 |
2004年 | 834篇 |
2003年 | 765篇 |
2002年 | 762篇 |
2001年 | 496篇 |
2000年 | 475篇 |
1999年 | 464篇 |
1998年 | 178篇 |
1997年 | 145篇 |
1996年 | 144篇 |
1995年 | 119篇 |
1994年 | 102篇 |
1993年 | 70篇 |
1992年 | 261篇 |
1991年 | 212篇 |
1990年 | 234篇 |
1989年 | 269篇 |
1988年 | 265篇 |
1987年 | 249篇 |
1986年 | 219篇 |
1985年 | 219篇 |
1984年 | 124篇 |
1983年 | 118篇 |
1982年 | 48篇 |
1979年 | 105篇 |
1978年 | 69篇 |
1977年 | 49篇 |
1974年 | 42篇 |
1972年 | 51篇 |
1971年 | 52篇 |
1970年 | 47篇 |
1969年 | 57篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
1.
2.
3.
Hideki Kawaguchi Kazuko Masuo Tomohiro Katsuya Ken Sugimoto Hiromi Rakugi Toshio Ogihara Michael L Tuck 《Hypertension research》2006,29(12):951-959
High blood pressure (BP) is a major determinant of cardiovascular events in obesity. The beta2- and beta3-adrenoceptor polymorphisms are associated with obesity and hypertension. In the present study, we examine the relationships of beta2- and beta3-adrenoceptor polymorphisms with further weight gain-induced BP elevation in obese subjects. Changes in BP, body weight, total body fat-mass, waist-to-hip ratio, plasma norepinephrine (NE) and leptin levels, and beta2(Arg16Gly)- and beta3(Trp64Arg)-adrenoceptor polymorphisms were measured periodically over a 5-year period in 55 entry obese (body mass index [BMI]> or =25.0 kg/m(2)) normotensive (BP<140/90 mmHg) men. BP elevation and weight gain were defined as > or =10% increases from entry levels over 5 years in mean BP or BMI. Obese subjects with weight gain, BP elevation or weight gain-induced BP elevation had higher frequencies of the Gly16 allele of Arg16GIy and Arg64 allele of Trp64Arg. Subjects carrying the Gly16 or Arg64 alleles had significantly greater total fat-mass and waist-to-hip ratio at entry and over a 5-year period compared to the subjects who did not carry these polymorphisms. Subjects carrying the Gly16 allele had similar levels of plasma NE, higher levels of plasma leptin and a lower slope of the regression lines between plasma leptin and NE levels. Those carrying the Arg64 allele had higher plasma NE levels at entry and over a 5-year period compared to the subjects without the Arg64 allele, but plasma leptin levels and slopes were similar. The findings demonstrate that the Arg64 allele of the beta3-adrenoceptor polymorphisms relates to weight gain-induced BP elevation accompanying high plasma NE (heightened sympathetic activity) in obese men. The Gly16 allele of the beta2-adrenoceptor polymorphisms links to weight gain-induced BP elevation associated with leptin resistance. beta2- and beta3-adrenoceptor polymorphisms could predict the future BP elevation and further weight gain-induced BP elevation in originally obese subjects. 相似文献
4.
S Yamaguchi H Fujii S Kaneko S Yachiku F Inada T Anzai T Kobayashi K Furuta H Ishida 《Nihon Hinyōkika Gakkai zasshi. The japanese journal of urology》1991,82(10):1561-1567
Ultrasonotomograms of 22 kidneys were obtained in 11 patients with renal-acute renal failure (renal-ARF). The underlying diseases of renal-ARF were acute tubular necrosis in 8 patients and acute on-set chronic glomerulonephritis in 3 patients. They were treated by hemodialysis in 10 patients and intermittent peritoneal dialysis in 1 patient. Ultrasonic measurement of the size of kidneys revealed that the thickness (anterior-posterior diameter) and the ratio of thickness to length (T/L) were greater in patients with ARF than in those with chronic renal failure and normal renal function. The patients with a low value of T/L (under 0.60) had a significantly greater urine volume than those with high a value of T/L (0.60 or more). The sonographic features of renal-ARF kidneys were marked increase in parenchymal echogenicity and appearance of hypoechoic swollen renal pyramids with sharpness of the corticomedullary border. In the course of ARF, these sonographic changes gradually disappeared when the patients had recovered from ARF. However, the prognosis was poor in patients with severer sonographic findings. We believe that repeated ultrasonic examination of the kidneys in patients with renal-ARF is useful for not only differential diagnosis of post-renal urinary obstruction but evaluating the course of ARF. 相似文献
5.
6.
Yuko Kamio Yurika Saito Naoki Utoguchi Masuo Kondoh Naoya Koizumi Makiko Fujii Yoshiteru Watanabe 《Journal of controlled release》2005,102(3):563-568
Some physiological substances, including acetylcholine and nitric oxide, are useful candidates for stimulation of intestinal absorption of drugs. In the present study, we elucidated the ability of epinephrine (Epi) to stimulate the intestinal absorption of drugs. We evaluated the ability of Epi to enhance absorption of macromolecules using dextran (Mw 4000 Da), which is poorly absorbed from the intestine, as a model compound in situ in a closed loop of the rat jejunum. Treatment of the jejunum with Epi resulted in significant increase in absorption of dextran in a dose-dependent fashion. The area under the curve (AUC) from 0 to 4 h in the Epi-treated jejunum was 13-fold higher than that in the vehicle-treated jejunum. The absorption-enhancing activity of Epi was 40-fold higher than that of caprate, a clinically used absorption-enhancer of drugs. In the experimental conditions used in this study, histological injury of the mucosa and perturbation of the mucosal membrane were not observed in the Epi-treated jejunum. Treatment with an antagonist of alpha-adrenergic receptors attenuated the stimulation of intestinal absorption by Epi, and treatment with an agonist of alpha-adrenergic receptors resulted in enhancement of intestinal absorption. While an antagonist of beta-adrenergic receptors enhanced the absorption-enhancing effect of Epi, an agonist of beta-adrenergic receptors stimulated intestinal absorption. These results indicate that stimulation of adrenergic receptors may be a novel strategy for intestinal absorption of drugs. 相似文献
7.
8.
Takanori Kikuchi Naoshi Fukui Tomohiro Sakuta Toshijiro Yamaguchi Hiroya Sakai Hiromi Oda 《Journal of orthopaedic science》1997,2(1):31-39
The midportion of the anterior cruciate ligament (ACL) of rabbits was partially transected, and the effect of hyaluronan (HA) on its healing was determined. A 1% solution of HA (HA group) or physiological phosphate-buffered saline (control group) was administered intraarticularly, at 0.1 ml/kg body weight, once a week from 1 week after the operation. Two, 4, and 6 weeks after the initiation of HA administration, the ACLs were examined grossly, histologically and immunohistochemically. At 2 weeks, the lacerated portions were completely covered with scar-like tissue in both groups. These tissue areas were smaller in the HA group than in the control group. Histologically in the HA group, the regularity of collagen fibers (indicating the maturity of regenerated collagen fibers) had increased compared to findings in the control group, and the number of fibroblastic cells decreased gradually at a significantly faster rate. The number of inflammatory cells and blood vessels decreased gradually in both groups, with these values being lower in the HA group at each time point but not significantly so. Immunohistochemical examination of the repaired tissue revealed strong staining with anti-chondroitin sulfate proteoglycan antibody in the HA group 2 weeks after the first HA administration. The staining gradually became reduced, with the rate of reduction being faster in the HA group than in the control group. The stimulation of chondroitin sulfate proteoglycan production and the faster reduction of it in the HA group suggests that HA facilitated tissue repair and inhibited the formation of scar tissue. 相似文献
9.
10.
H Meguro O Arimasu H Sohda J Yoshida K Togasaki R Fujii 《The Japanese journal of antibiotics》1986,39(4):1007-1019
A new beta-lactamase-stable oral cephem antibiotic, cefixime (CFIX), was evaluated for safety, efficacy and pharmacokinetics in children. CFIX was effective in 19 of 20 cases (95%) with bacterial infections. The drug was especially effective against the cases of pneumonia due to beta-lactamase-producing H. influenzae or B. catarrhalis. Pharmacokinetic parameters of CFIX (3 mg/kg) with premeal administration were as follows: Kel 0.328 +/- 0.066 hr-1, T 1/2 2.14 +/- 0.36 hrs, AUC 10.9 +/- 8.7 micrograms X hr/ml, and Vd/F 1.64 +/- 1.42 L/kg. In most of the cases tested, the urinary excretion rate in 12 hours was 5 to 17%. A dose of 3 mg/kg twice daily seems to be adequate for a regular treatment. 相似文献