全文获取类型
收费全文 | 1011366篇 |
免费 | 76242篇 |
国内免费 | 2635篇 |
专业分类
耳鼻咽喉 | 13132篇 |
儿科学 | 34907篇 |
妇产科学 | 28720篇 |
基础医学 | 147198篇 |
口腔科学 | 27901篇 |
临床医学 | 92057篇 |
内科学 | 196428篇 |
皮肤病学 | 23149篇 |
神经病学 | 80616篇 |
特种医学 | 38736篇 |
外国民族医学 | 307篇 |
外科学 | 150957篇 |
综合类 | 23885篇 |
一般理论 | 396篇 |
预防医学 | 79405篇 |
眼科学 | 22915篇 |
药学 | 72756篇 |
3篇 | |
中国医学 | 2056篇 |
肿瘤学 | 54719篇 |
出版年
2018年 | 10890篇 |
2017年 | 8517篇 |
2016年 | 9663篇 |
2015年 | 10918篇 |
2014年 | 14901篇 |
2013年 | 22661篇 |
2012年 | 30030篇 |
2011年 | 31932篇 |
2010年 | 19040篇 |
2009年 | 17960篇 |
2008年 | 29693篇 |
2007年 | 31377篇 |
2006年 | 31861篇 |
2005年 | 30535篇 |
2004年 | 29815篇 |
2003年 | 28614篇 |
2002年 | 27555篇 |
2001年 | 47047篇 |
2000年 | 48129篇 |
1999年 | 40408篇 |
1998年 | 11340篇 |
1997年 | 10218篇 |
1996年 | 10280篇 |
1995年 | 9881篇 |
1994年 | 9175篇 |
1993年 | 8562篇 |
1992年 | 32319篇 |
1991年 | 31544篇 |
1990年 | 31070篇 |
1989年 | 29933篇 |
1988年 | 27227篇 |
1987年 | 27394篇 |
1986年 | 25504篇 |
1985年 | 24660篇 |
1984年 | 18458篇 |
1983年 | 15562篇 |
1982年 | 9329篇 |
1981年 | 8418篇 |
1979年 | 16892篇 |
1978年 | 12246篇 |
1977年 | 10339篇 |
1976年 | 9783篇 |
1975年 | 10215篇 |
1974年 | 12345篇 |
1973年 | 11860篇 |
1972年 | 10909篇 |
1971年 | 10129篇 |
1970年 | 9401篇 |
1969年 | 8740篇 |
1968年 | 8121篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
91.
Recurrent erosion 总被引:1,自引:0,他引:1
92.
R W Hertle A B Leahey S Bloom D B Schaffer S Bartlett 《Ophthalmic plastic and reconstructive surgery》1990,6(4):278-282
Chorioretinal folds have been reported as a result of many intraocular and extraocular inflammatory processes or tumors. Visual loss is usually secondary to a combination of the underlying process and chorioretinal folds involving the macula. We report a patient who developed decreased vision, metamorphopsia, chorioretinal folds, and a lamellar macular hole secondary to global compression by a bone fragment. The chorioretinal folds regressed and his vision stabilized following surgical decompression. Chorioretinal folds and lamellar macular hold formation are previously unrecognized complications of reconstructive craniofacial surgery. 相似文献
93.
J. M. Falletta B. Cushing S. Lauer B. Bell D. H. Mahoney R. Castleberry R. A. Krance 《Investigational new drugs》1990,8(2):167-170
Summary We conducted a phase I clinical study of aziridinylbenzoquinone (Diaziquone, AZQ) given as a 4 hour infusion weekly × 4. Forty-five children with recurrent acute leukemia and 33 children with various advanced solid tumors participated. Severe myelosuppression was the dose limiting toxic effect, occurring in all patients at the upper dose levels. Gastrointestinal and hepatic toxicities were infrequent and not severe. No allergic reactions occurred. Objective tumor regression was noted in 3 of 25 patients with a CNS tumor and in 6 of 45 patients with acute leukemia. For phase II trials the recommended dosage of Diaziquone given by this schedule is 18 mg/M2×4 for patients with a solid tumor, and is 30 mg/M2/week × 4 for children with acute leukemia. 相似文献
94.
95.
SRIVASTAVA Z. I.; MATHUR N.; RASTOGI S. K.; GUPTA B. N. 《Occupational medicine (Oxford, England)》1988,38(4):134-136
Eighty-nine cases of chronic bronchitis were matched against167 asymptomatic controls from the glass bangle industry ofFirozabad. Factors of age, social status, smoking habit andduration of exposure were studied. Duration of exposure wasfound to be a factor contributing significantly to the causationof disease.
Requests for reprints should be addressed to: Dr B. N. Gupta, Division of Epidemilogy, Industrial Toxicology Research Centre, Mahatma Gandhi Marg, Lucknow P.O. Box 80, 226001, India 相似文献
96.
The composition of the clientele from an ophthalmological practitioner's office is described with special reference to the occurrence of glaucoma and disc haemorrhages (h in singular; hh in plural). This study could not be planned as an epidemiological survey and gives no clue to sensitivity or specificity of hh in glaucoma. During a period of about 10 years ending with 1986 there were 731 patients with h and/or glaucoma. When detected, 185 patients had h but no glaucoma, 33 had both h and glaucoma and 513 had glaucoma but no h. During the follow-up period hh were detected in 83 cases of glaucoma, and glaucoma developed in 27 cases with hh. The detection rate of hh among glaucoma was low but steady, indicating that hh may occur at any stage of the glaucoma process. This study shows no predilection for hh in cases with general hypertension or diabetes, nor is the frequency of hh among pseudoexfoliation cases significantly lower than among cases without this stigma. 相似文献
97.
Isotretinoin (Accutane Capsules) is a synthetic vitamin A compound used for treatment of recalcitrant cystic acne. It has numerous ocular toxic side effects which include anterior segment inflammation, dry eye syndrome, contact lens intolerance, altered refraction, photosensitivity, and reduced night vision. Eye care practitioners should be aware of these potential side effects and be prepared to communicate with the prescribing physician if side effects present. 相似文献
98.
Although extracellular matrix (ECM) glycoproteins play important roles in neural development, their levels are generally believed to decrease in the adult brain. Immunohistochemical analysis indicates that the anti-adhesive ECM glycoprotein SPARC/osteonectin, which contains a follistatin ‘module’, is expressed in the adult rabbit nervous system. In the cerebellum, SPARC is present in Bergmann glia, with a strong signal along their radial fibres. SPARC, while enriched in membrane fractions, is not a transmembrane protein. In the hippocampus, colocalization of SPARC is observed in cells which express the astrocytic marker GFAP. The expression of SPARC by a subset of astrocytes, particularly in synaptic enriched areas, suggests a continuing role for the ECM in the adult brain. 相似文献
99.
Xu Dai-gen He Han-zhen Zhang Guo-gao B. Gansewendt H. Peter H. M. Bolt 《华中科技大学学报(医学英德文版)》1993,13(2):100-104
Monohalogenated methanes (methyl chloride, methyl bromide and methyl iodide) are mutagenic and carcinogenic. The possible mechanism of these effects, DNA methylation, was studied. DNA adducts from orgnas of F344 rats exposed to these chemicals were separated and identified with high performance liquid chromatography (HPLC) and gaschro-matography/massspectrometry (GC/ MS). DNA adducts, 7-methylguanine (7-MeG) and O6-Methylguanine(08-MeG), incorporation of14C into de novo synthesis of nucleobases could be observed in enzymatic DNA hydrolysates by HPLC and determination of the radioactivity in the fractions. The formation of DNA add,ue,ts in the studied organs was only quantitatively different. The formation of O6-MeG was further pioved by analysing the acidic hydrolysates using HPLC with non-radioactive O6MeG as internal standard. 7-MeG and 3-MeA were identified with GC/MS analysis. 相似文献
100.
P. A. Milligan P. E. McGill C. W. Howden A. W. Kelman B. Whiting 《European journal of clinical pharmacology》1993,45(6):507-512
Summary A randomised crossover study was performed in subjects with rheumatoid arthritis (or other arthropathies) to investigate if any alteration in the steady pharmacokinetics of the NSAID piroxicam (a drug which is extensively metabolised via cytochrome P450) or its major metabolites occurred as a result of coadministering either cimetidine or nizatidine.Twelve females and 2 males with mean age, weight, and albumin concentrations of 58 years, 61 kg, and 40 g·L–1 respectively, completed the study. Comparisons were made between the following parameters: plasma piroxicam AUCs [AUC0-24(P)], plasma 5-hydroxypiroxicam AUCs [AUC0-24(5-OHP)], the ratio of these i.e. AUC0-24(5-OHP):AUC0-24(p), the % piroxicam daily dose excreted in urine as 5-hydroxypiroxicam (before and after glucuronidase incubation); and the mean of the steady state trough piroxicam, and 5-hydroxypiroxicam concentrations (obtained during each study phase in addition to the wash-out period).A statistically significant difference as a result of initiating either cimetidine or nizatidine was obtained only for the ratio AUC0-23(5-OHP):AUC0-24(P). This was indicative of a weak potential to inhibit piroxicam hydroxylation.No clinically significant alteration in the steady state pharmacokinetics of piroxicam occurred in these subjects as a result of cimetidine or nizatidine coadministration. Consequently it is unlikely that any adverse events would arise from these combinations. 相似文献