全文获取类型
收费全文 | 2167904篇 |
免费 | 167066篇 |
国内免费 | 4353篇 |
专业分类
耳鼻咽喉 | 29416篇 |
儿科学 | 66437篇 |
妇产科学 | 59461篇 |
基础医学 | 307680篇 |
口腔科学 | 61925篇 |
临床医学 | 193274篇 |
内科学 | 429537篇 |
皮肤病学 | 48766篇 |
神经病学 | 175476篇 |
特种医学 | 83276篇 |
外国民族医学 | 536篇 |
外科学 | 334814篇 |
综合类 | 47169篇 |
现状与发展 | 4篇 |
一般理论 | 691篇 |
预防医学 | 161720篇 |
眼科学 | 49561篇 |
药学 | 159020篇 |
5篇 | |
中国医学 | 4865篇 |
肿瘤学 | 125690篇 |
出版年
2019年 | 16224篇 |
2018年 | 23325篇 |
2017年 | 17979篇 |
2016年 | 20118篇 |
2015年 | 22665篇 |
2014年 | 31657篇 |
2013年 | 47150篇 |
2012年 | 64000篇 |
2011年 | 67484篇 |
2010年 | 39817篇 |
2009年 | 38186篇 |
2008年 | 63740篇 |
2007年 | 67322篇 |
2006年 | 68376篇 |
2005年 | 66198篇 |
2004年 | 63428篇 |
2003年 | 60865篇 |
2002年 | 59081篇 |
2001年 | 114697篇 |
2000年 | 117666篇 |
1999年 | 97734篇 |
1998年 | 25674篇 |
1997年 | 22949篇 |
1996年 | 23071篇 |
1995年 | 21849篇 |
1994年 | 19950篇 |
1993年 | 18608篇 |
1992年 | 74280篇 |
1991年 | 71058篇 |
1990年 | 68354篇 |
1989年 | 65897篇 |
1988年 | 60353篇 |
1987年 | 58917篇 |
1986年 | 54841篇 |
1985年 | 52596篇 |
1984年 | 38933篇 |
1983年 | 32834篇 |
1982年 | 18845篇 |
1981年 | 16563篇 |
1979年 | 34347篇 |
1978年 | 23716篇 |
1977年 | 19953篇 |
1976年 | 18198篇 |
1975年 | 19153篇 |
1974年 | 23261篇 |
1973年 | 22271篇 |
1972年 | 20936篇 |
1971年 | 19368篇 |
1970年 | 18426篇 |
1969年 | 17219篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
G F Watts L Gregory R Naoumova C Kubal K M Shaw 《European journal of clinical nutrition》1988,42(8):697-702
The onset of diabetic nephropathy is characterized by subclinical elevation of urinary albumin excretion, so-called 'microalbuminuria' (M). Dietary assessments were carried out in 15 insulin-dependent diabetic patients with persistent M and an equal number with persistently normal albumin excretion. The groups were matched for sex, age, duration of diabetes, body mass index, insulin dose and glycosylated haemoglobin; there were no significant differences in systemic blood pressure, glomerular filtration rate, blood glucose and serum albumin concentrations between the groups; retinopathy was significantly more frequent in patients with M. Diabetics with persistent M were found to consume a significantly larger amount of fat (expressed as grams and percentage of total energy) and a significantly smaller percentage of total energy as carbohydrate than patients with normal albumin excretion; total dietary energy was larger in those with persistent M, but the difference was not significant. No significant differences were found in protein and fibre intakes between the groups. Our findings suggest that an excess in the dietary consumption of fat relative to carbohydrate might play an important role in the pathogenesis of early nephropathy in insulin-dependent diabetes mellitus. We emphasize the importance of careful attention to nutrient intake in the prevention and treatment of diabetic complications. 相似文献
992.
Treatment versus no treatment in chronic open angle glaucoma 总被引:1,自引:0,他引:1
In a controlled randomized study 15 patients (20 eyes) with chronic open angle glaucoma and visual field defects were followed by greater than 1 year, 12 of them were followed for 3 years. Half of the group were untreated controls, the other half treated with pressure reducing medical therapy. At least 5 consecutive computerized visual fields were recorded (COMPETER) on each eye, and the linear regression coefficient was calculated. With the reservation for uncontrolled compliance no significant difference in the line of favourable effect of pressure reduction could be spotted, in spite of an average pressure reduction in the treated group of 4 mmHg. More important than this result, which is open to criticism for the smallness of the material, uncontrolled compliance etc, is the lesson that a randomized experiment with treated and non-treated glaucoma cases carried out in accordance with the Helsingfors convention is hardly feasible. 相似文献
993.
The YAG (yttrium aluminum garnet) laser has been recommended for anterior capsulotomies. One major complication is elevated intraocular pressure. We report a study of the biochemical content of the aqueous humor after a YAG laser anterior capsulotomy. We analyzed 6-keto-prostaglandin F1 alpha, thromboxane B2 and protein concentrations in the aqueous humor of human eyes. The average values of protein, 6-keto-prostaglandin F1 alpha, and thromboxane B2 in the control eyes were 81.3 +/- 14.0 mg/dL, 17 +/- 30 pg/mL, and 10 +/- 10 pg/mL, respectively. These values were elevated to 182.4 +/- 81.3 mg/dL, 401 +/- 55 pg/mL, and 576 +/- 148 pg/mL, respectively, after YAG laser anterior capsulotomy. The samples with a moderate level of 6-keto-prostaglandin F1 alpha (less than 300 pg/mL) had negligible changes of thromboxane. The elevation of thromboxane was obvious only when prostaglandin levels rose above 300 pg/mL. 相似文献
994.
S de Bustros J T Thompson R G Michels T A Rice B M Glaser 《The British journal of ophthalmology》1988,72(9):692-695
We used vitreous surgery to remove idiopathic epiretinal membranes from the macular area in 70 consecutive cases. The abnormal tissue was successfully removed in each case. Vision improved postoperatively in 61 eyes (87%), remained unchanged in six eyes (9%), and worsened in three eyes (4%). However, at the time of final examination vision was improved in only 47 eyes (67%), primarily because of the occurrence or progression of nuclear sclerosis, which occurred in 38 of 60 phakic eyes (63%). Four preoperative factors were associated with final visual acuity of 20/60 or better: (1) initial vision of 20/100 or better, (2) shorter preoperative duration of blurred vision, (3) thin epiretinal membrane, and (4) absence of traction retinal detachment. 相似文献
995.
Of 7 plasmids we tested, the plasmid pORF2 was eliminated in vitro with the most efficiency by treatment with subinhibitory concentrations of novobiocin, coumermycin and 10 quinolones. It showed a cure rate of 43% by enoxacin; 12% by novobiocin, pefloxacin, ciprofloxacin and CI-934; 7% by coumermycin and ofloxacin; 9% by amifloxacin; and 4% by AM-833. On the other hand, pSC194, pBR322 and pMH612 were poorly cured in vitro by quinolones, except pSC194 which was cured 33% by enoxacin. R1, pP1603, and pUB110 were unaffected by the treatment. Mice were challenged intraperitoneally with a 2XLD50 of Escherichia coli carrying the ORF2 plasmid and were treated per os with 1 X or 1/2 X ED50 of either enoxacin or CI-934. The frequency of loss of ampicillin resistance determined 3 h after treatment shows curing effects of 92% for CI-934, 89% for enoxacin and 20% for untreated control. 相似文献
996.
997.
998.
S C Joseph 《Journal of urban health》1988,64(6):506-512
999.
1000.