全文获取类型
收费全文 | 997388篇 |
免费 | 75238篇 |
国内免费 | 2616篇 |
专业分类
耳鼻咽喉 | 12961篇 |
儿科学 | 34464篇 |
妇产科学 | 28460篇 |
基础医学 | 145276篇 |
口腔科学 | 27714篇 |
临床医学 | 90265篇 |
内科学 | 193542篇 |
皮肤病学 | 22912篇 |
神经病学 | 79106篇 |
特种医学 | 38385篇 |
外国民族医学 | 305篇 |
外科学 | 149483篇 |
综合类 | 23738篇 |
一般理论 | 385篇 |
预防医学 | 77818篇 |
眼科学 | 22606篇 |
药学 | 71860篇 |
3篇 | |
中国医学 | 2030篇 |
肿瘤学 | 53929篇 |
出版年
2018年 | 10555篇 |
2017年 | 8235篇 |
2016年 | 9373篇 |
2015年 | 10594篇 |
2014年 | 14415篇 |
2013年 | 22000篇 |
2012年 | 28981篇 |
2011年 | 30824篇 |
2010年 | 18487篇 |
2009年 | 17435篇 |
2008年 | 28788篇 |
2007年 | 30459篇 |
2006年 | 30959篇 |
2005年 | 29637篇 |
2004年 | 28924篇 |
2003年 | 27796篇 |
2002年 | 26812篇 |
2001年 | 46924篇 |
2000年 | 48033篇 |
1999年 | 40262篇 |
1998年 | 11177篇 |
1997年 | 10095篇 |
1996年 | 10160篇 |
1995年 | 9775篇 |
1994年 | 9090篇 |
1993年 | 8480篇 |
1992年 | 32248篇 |
1991年 | 31458篇 |
1990年 | 31006篇 |
1989年 | 29874篇 |
1988年 | 27167篇 |
1987年 | 27325篇 |
1986年 | 25434篇 |
1985年 | 24601篇 |
1984年 | 18397篇 |
1983年 | 15515篇 |
1982年 | 9288篇 |
1981年 | 8375篇 |
1979年 | 16859篇 |
1978年 | 12217篇 |
1977年 | 10314篇 |
1976年 | 9754篇 |
1975年 | 10178篇 |
1974年 | 12317篇 |
1973年 | 11843篇 |
1972年 | 10884篇 |
1971年 | 10113篇 |
1970年 | 9375篇 |
1969年 | 8724篇 |
1968年 | 8104篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
221.
G Benton R C Thomas B G Nickerson J C McQuitty J Okikawa 《American journal of diseases of children (1960)》1989,143(6):678-681
Studies of adults suggest that metered-dose inhalers with spacers are as effective as hand-held nebulizers for bronchodilator delivery. We studied 13 children with acute asthma. They received two puffs every 2 minutes from metered-dose inhalers with spacers (range, 4 to 14 puffs) titrated until improvement stopped. Peak expiratory flow increased 34% for metered-dose inhalers with spacers after the first 2 puffs and increased 87% for metered-dose inhalers with spacers after dose titration. After titration, respiratory rate decreased by 12%, heart rate increased by 2%, and breath sounds improved in 92% of the patients. We concluded that the metered-dose inhalers with spacers are an effective device for the treatment of asthma in the pediatric emergency department and that the use of metered-dose inhalers with spacers with titration can achieve significant bronchodilation in the treatment of patients with acute asthma. 相似文献
222.
Experimental results in female rats with marginal magnesium deficiency a and clinical results in over 100 female tetanic patients suggest the deleterious influence of magnesium on oro-facial tissues. 相似文献
223.
Extensive clinical experience and anecdotal evidence indicate that application of laser technology has improved the management of many congenital and acquired diseases of the head and neck in pediatric patients. The general principles of laser surgery, with respect to laser-tissue interaction, must be adhered to at all times to achieve the best surgical effect. Improperly used, the laser can damage normal tissue in the infant's or child's larynx, with devastating consequences. 相似文献
224.
225.
Phase I study of high-dose cytosine arabinoside and etoposide in patients with advanced malignancies
Bayard L. Powell Hyman B. Muss Robert L. Capizzi Mary E. Caponera Douglas R. White Patricia J. Zekan James N. Atkins Don V. Jackson Jr. Frederick Richards II John B. Craig Julia M. Cruz Charles L. Spurr 《Cancer chemotherapy and pharmacology》1987,19(3):250-252
Summary Cytosine arabinsodie (ara-C) and etoposide (VP-16) display synergy in the laboratory. Twenty-six patients participated in a phase I study of high-dose ara-C in combination with VP-16. The dose of VP-16 was held constant at 50 mg/m2 as an intermittent infusion over 33 h; escalating doses of ara-C were given as infusions during hours 9–12 and 21–24. Myelosuppression was the dose-limiting toxicity and occurred with doses considerably less than those expected from studies of the two drugs as single agents. The suggested initial doses for phase II trials with this schedule are 750 mg/m2×2 doses of ara-C and 50 mg/m2 of VP-16. Nonhematologic toxicity was minimal; therefore, further dose escalation is feasible in patients in whom myelosuppression is acceptable.Supported in part by grants from the National Cancer Institute (CA-12197 and CA-09422) and the American Cancer Society CF-85-182 相似文献
226.
4-Aminopyridine affects synaptosomal protein phosphorylation in rat hippocampal slices 总被引:2,自引:0,他引:2
Rat brain hippocampal slices were incubated with or without the convulsant 4-aminopyridine (4-AP). From these slices a crude mitochondrial/synaptosomal membrane fraction was prepared and analyzed for endogenous protein phosphorylation. 4-AP (10(-5) M) stimulated the phosphorylation of a 50 kDa protein by 86%. The phosphorylation of this 50 kDa protein is Ca2+/calmodulin-dependent and we suggest that this protein is the lower molecular weight subunit of Ca2+/calmodulin-dependent protein kinase II (CaMK II). 相似文献
227.
228.
The relationship between the immunoglobulin kappa light chain allotypes and autoantibodies was studied in a series of seven human monoclonal kappa-bearing IgM antibodies with Rheumatoid Factor (RF) activity, two IgM anti-low density lipoprotein (LDL) antibodies, and one IgM anti-intermediate filament (IF) antibody. Residues at amino acid positions 153 and 191 related to the Km allotypes in human kappa chains were determined by an HPLC tryptic fingerprint and corroborated by amino acid sequence analysis. All the autoantibodies shared similar variable regions derived from the V kappa IIIb gene(s). The seven RF and the anti-IF were associated with the Km(3) constant region allotype whereas the two anti-LDL were associated with the Km(1,2) allotype. Thus, monoclonal autoantibodies showed the same Km allotypic distribution as the normal population. However, although the number of samples is small, it seems likely that a preferential association may exist between particular V kappa genes and Km alleles in the generation of autoantibodies with different specificities. 相似文献
229.
R W Wulkan L Zwang T L Liem B G Blijenberg B Leijnse 《Zeitschrift für klinische Chemie und klinische Biochemie》1987,25(10):719-722
An expert system for evaluation of X-ray diffraction patterns of urinary calculi is described and evaluated. The software was developed using the PERSONAL CONSULTANT expert system shell from Texas Instruments. 相似文献
230.
The authors have presented the results of a 14-day open randomized trial of the efficacy of 3 calcium inlet blocking agents: nifedipine, verapamil and phendilin in 61 patients with Raynaud's syndrome. In the group of patients receiving 30-80 mg of nifedipine (20) there was a significant decrease in the frequency and expression of Raynaud's syndrome attacks, a positive effect of varying degree was noted in 19 patients. The drug raised slightly the skin and muscular blood flow and skin temperature. The use of 120-360 mg of verapamil in 21 patients caused no significant inhibition of Raynaud's syndrome and rise of hemocirculation. Phendilin (150-300 mg) though being comparable with nifedipine in efficacy, often produced side-effects resulting in the drug cancellation (8 out of 20). The efficacy of the calcium inlet blocking agents, especially nifedipine, for therapy of Raynaud's syndrome was emphasized. 相似文献