全文获取类型
收费全文 | 108172篇 |
免费 | 7689篇 |
国内免费 | 4697篇 |
专业分类
耳鼻咽喉 | 931篇 |
儿科学 | 1958篇 |
妇产科学 | 1171篇 |
基础医学 | 16645篇 |
口腔科学 | 2502篇 |
临床医学 | 8656篇 |
内科学 | 17661篇 |
皮肤病学 | 1470篇 |
神经病学 | 9724篇 |
特种医学 | 1776篇 |
外国民族医学 | 18篇 |
外科学 | 7577篇 |
综合类 | 17500篇 |
现状与发展 | 22篇 |
预防医学 | 5741篇 |
眼科学 | 2856篇 |
药学 | 13810篇 |
19篇 | |
中国医学 | 4282篇 |
肿瘤学 | 6239篇 |
出版年
2024年 | 231篇 |
2023年 | 1185篇 |
2022年 | 2813篇 |
2021年 | 3870篇 |
2020年 | 3114篇 |
2019年 | 2766篇 |
2018年 | 2751篇 |
2017年 | 3087篇 |
2016年 | 3439篇 |
2015年 | 3866篇 |
2014年 | 6417篇 |
2013年 | 7246篇 |
2012年 | 6696篇 |
2011年 | 7331篇 |
2010年 | 6020篇 |
2009年 | 5825篇 |
2008年 | 5992篇 |
2007年 | 5839篇 |
2006年 | 5274篇 |
2005年 | 4962篇 |
2004年 | 4080篇 |
2003年 | 3568篇 |
2002年 | 2795篇 |
2001年 | 2435篇 |
2000年 | 2099篇 |
1999年 | 1849篇 |
1998年 | 1718篇 |
1997年 | 1534篇 |
1996年 | 1309篇 |
1995年 | 1094篇 |
1994年 | 1022篇 |
1993年 | 856篇 |
1992年 | 787篇 |
1991年 | 749篇 |
1990年 | 622篇 |
1989年 | 541篇 |
1988年 | 484篇 |
1987年 | 464篇 |
1986年 | 418篇 |
1985年 | 613篇 |
1984年 | 523篇 |
1983年 | 356篇 |
1982年 | 438篇 |
1981年 | 337篇 |
1980年 | 298篇 |
1979年 | 191篇 |
1978年 | 165篇 |
1977年 | 139篇 |
1976年 | 117篇 |
1975年 | 73篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
C. J. HARRISON J. W. L. PUNTIS G. M. DURBIN P. GORNALL I. W. BOOTH 《Acta paediatrica (Oslo, Norway : 1992)》1991,80(11):1113-1116
ABSTRACT. Two atypical cases of colitis due to cow's milk protein intolerance (CMPI) are reported, affecting preterm infants. One developed a toxic dilatation of the colon and responded well to a casein hydrolysate based feed. The second presented insidiously and failed to tolerate a casein hydrolysate, but responded well to a chicken-based modular feed. 相似文献
82.
Summary. Parameters were obtained from the reproductive organs of ethanol-fed, gossypol-treated Sprague Dawley rats. The experimental animals were fed either on a normal (15.17%) or low protein (8.00%) diet. Measurements included reproductive organ weights, seminal characteristics, serum concentration of testosterone and histological, stereological and histomorphometric evaluation of the testis. The testis size, length and diameter of the seminiferous tubule had the least values in the protein-malnourished, gossy-pol-treated rats (3.01±0.26 g, 0.56 ± 0.03 m, 281.34±11.30 μn), in comparison to corresponding animals which had received ethanol simultaneously with gossypol (3.40 ± 0.25, 0.71±0.06m, 314.42 ± 11.61 μn). As gossypol and ethanol are both associated with reduced reproductive capacity, this unexpected but interesting finding lends support to the hypothesis that either a normal dietary protein or ethanol consumption may modify the action of gossypol on body tissues, including the testis. This effect, presumably mediated through changes caused to the bioavailability of gossypol, modifies its antifertility activity. The present observation further highlights the need to consider the concurrent administration of other drugs, such as alcohol, and the nutritional status in the evaluation of gossypol for various potential uses. 相似文献
83.
84.
Kousaku Matsubara M.D. Kei Suzuki M.D. Ying Wei Lin M.D. Toshiyuki Yamamoto M.D. Shigeru Ohta M.D. 《Pediatrics international》1991,33(4):482-487
We present two female siblings with familial juvenile nephronophthisis (FJN) which was diagnosed at the early stage of renal failure. Diagnosis was made during the investigation of anemia in case 1 and by a subsequent family survey in case 2. Most patients with FJN are not identified until the terminal stage of renal failure and such cases have rarely been reported in Japan. Case 2 had a reduction in the maximum urinary concentration ability but no azotemia, and among the FJN patients reported in Japan so far she has the least advanced renal disease. Histological examination of the renal biopsy in case 1 showed typical findings of FJN, such as thickening and lamination of the tubular basement membrane (TBM), interstitial fibrosis, and round cell infiltration of the interstitium. In case 2, renal biopsy revealed an irregular marked thickening of the TBM with trivial interstitial changes and a normal glomerular appearance. The histology of these two cases suggests that the TBM may be the primary site affected in FJN. 相似文献
85.
GP SCHWAB AL BLUM E BODNER B DALLEMAGNE K GLASER H KOOP F PACE W RÖSCH JR SIEWERT G WETSCHER 《Journal of gastroenterology and hepatology》1997,12(12):785-789
Gastroesophageal reflux disease (GERD) is the most common disease of the upper gastrointestinal tract. With the introduction of proton pump inhibitors medical treatment of GERD has been significantly improved. However, the development of laparoscopic antireflux surgery resulted in an increasing interest of surgeons in this disease. An interactive meeting was organized in order to develop an agreement between gastoenterologists and surgeons regarding therapeutic decisions and this is the main topic of this paper. 相似文献
86.
Efficient RT-PCR on platelet mRNA after long-term storage 总被引:1,自引:0,他引:1
We have developed a procedure permitting RT-PCR from mRNA even after a long-term storage (1 year) of platelet samples in ethanol (EtOH-platelets) at −80°C. To validate our method, we have analysed the human platelet alloantigen system (HPA-1) which is coded by β3 mRNA. We have also demonstrated the efficiency of amplification of part of the coding region for (i) αIIb subunit mRNA, (ii) αv subunit mRNA, and (iii) the seven transmembrane domain thrombin receptor mRNA. 相似文献
87.
88.
89.
硬膜外腔阻滞对胸部手术应激反应的影响 总被引:33,自引:1,他引:32
目的 观察硬膜外腔阻滞对胸部手术应激激素和细胞因子的影响。方法20例食管癌手术病人,随机分为两组,每组10例,即全麻复令硬膜外腔阻滞(GEA)组和全麻(GA)组,分别测定麻醉诱导前、手术2h、手术4h、术毕、术后1d及术后3d的血浆去甲肾上腺素、肾上腺素、血清促肾上腺皮质激素(ACTH)、皮质醇、C-反应蛋白、IL-6及IL-10的水平。结果 血浆去甲肾上腺素和血清皮质醇GEA组术中术后无显著改变,但GA组术毕和术后1d显著升高(P<0.05),术后3d恢复至术前水平,组间比较前者有显著差异(P<0.05)。两组血浆肾上腺素、IL-10术中术后均无显著变化。两组血清ACTH、IL-6及CRP术中术后均显著升高(P<0.05),组间比较无显著差异。结论 硬膜外腔阻滞可以减轻胸部手术的应激反应。IL-6是较CRP更灵敏的反映组织损伤的炎性指标。 相似文献
90.
Alexandra H. Heussner Evelyn O'Brien Daniel R. Dietrich 《Experimental and toxicologic pathology》2002,54(2):151-159
The mycotoxin ochratoxin A (OTA) is a potent renal carcinogen in rodents and induces renal fibrosis in pigs. Furthermore, OTA has been associated with the development of renal tumors and nephropathies in humans. Large species- and sex-differences are observed in sensitivity toward OTA-mediated toxicity and carcinogenicity, yet neither the mechanism(s) resulting in OTA toxicity nor the reasons for the observed species- and sex-specificities are known. This paper investigated variations in OTA handling viz binding to renal proteins which could possibly explain the observed differences in OTA susceptibility in vivo and in vitro. The results obtained via a modification of a standard receptor-binding assay demonstrated the presence of at least one homogeneous binding component in renal cortical homogenates from pig, mouse, rat and humans. This component was shown to bind OTA in a specific and saturable manner. A range of compounds selected for their affinity for steroid receptors and/or for various known organic anion transporters were employed in a competition assay to answer the question whether this homogenous OTA binding component represents a steroid-like receptor component or one of the known organic anion transporters of the kidney. Although many of the compounds were able to compete with OTA for protein-binding, the competition patterns displayed a distinct species specificity and did not correspond to the competition patterns associated with presently known organic anion transporters of the kidney in the mouse, rat or human. The data thus suggests the presence of a new organic anion transporter or more likely, a cytosolic binding component of unknown function with high affinity and capacity for OTA binding in humans, rats, mice and possibly pigs. 相似文献