全文获取类型
收费全文 | 1530篇 |
免费 | 103篇 |
国内免费 | 7篇 |
专业分类
耳鼻咽喉 | 28篇 |
儿科学 | 122篇 |
妇产科学 | 25篇 |
基础医学 | 248篇 |
口腔科学 | 20篇 |
临床医学 | 124篇 |
内科学 | 252篇 |
皮肤病学 | 19篇 |
神经病学 | 155篇 |
特种医学 | 39篇 |
外科学 | 179篇 |
综合类 | 9篇 |
一般理论 | 1篇 |
预防医学 | 169篇 |
眼科学 | 23篇 |
药学 | 128篇 |
中国医学 | 3篇 |
肿瘤学 | 96篇 |
出版年
2024年 | 2篇 |
2023年 | 15篇 |
2022年 | 24篇 |
2021年 | 65篇 |
2020年 | 47篇 |
2019年 | 48篇 |
2018年 | 66篇 |
2017年 | 47篇 |
2016年 | 56篇 |
2015年 | 45篇 |
2014年 | 64篇 |
2013年 | 89篇 |
2012年 | 133篇 |
2011年 | 115篇 |
2010年 | 74篇 |
2009年 | 57篇 |
2008年 | 107篇 |
2007年 | 90篇 |
2006年 | 79篇 |
2005年 | 71篇 |
2004年 | 76篇 |
2003年 | 58篇 |
2002年 | 69篇 |
2001年 | 15篇 |
2000年 | 17篇 |
1999年 | 14篇 |
1998年 | 12篇 |
1997年 | 8篇 |
1996年 | 6篇 |
1995年 | 8篇 |
1994年 | 6篇 |
1993年 | 3篇 |
1992年 | 7篇 |
1991年 | 3篇 |
1990年 | 3篇 |
1989年 | 3篇 |
1988年 | 2篇 |
1987年 | 3篇 |
1986年 | 4篇 |
1985年 | 3篇 |
1984年 | 5篇 |
1983年 | 6篇 |
1982年 | 2篇 |
1981年 | 2篇 |
1980年 | 1篇 |
1979年 | 2篇 |
1978年 | 6篇 |
1977年 | 2篇 |
排序方式: 共有1640条查询结果,搜索用时 31 毫秒
71.
72.
Antibodies against follicle-stimulating hormone (anti-FSH) are present in infertile female sera. Follicle-stimulating hormone as antigen is present in female sera and introduced to the genital tract mucosa as a constituent of semen. The female immune system is activated by semen constituents during insemination to induce mucosal tolerance. We found that circulating anti-FSH IgA correlated with IgA against sperm surface antigens in female patients undergoing IVF. Our results suggest that anti-FSH and anti-sperm IgA could share antigenic origin, being induced possibly by mucosal tolerance to semen. 相似文献
73.
Singh G Singh AT Abraham A Bhat B Mukherjee A Verma R Agarwal SK Jha S Mukherjee R Burman AC 《Journal of ethnopharmacology》2008,117(1):123-129
Terminalia arjuna has been marked as a potential cardioprotective agent since vedic period. The present study was aimed to investigate the effects of butanolic fraction of Terminalia arjuna bark (TA-05) on Doxorubicin (Dox)-induced cardiotoxicity. Male wistar rats were used as in vivo model for the study. TA-05 was administered orally to Wistar rats at different doses (0.42 mg/kg, 0.85 mg/kg, 1.7 mg/kg, 3.4 mg/kg and 6.8 mg/kg) for 6 days/week for 4 weeks. Thereafter, all the animals except saline and TA-05-treated controls were administered 20 mg/kg Dox intraperitonially. There was a significant decrease in myocardial superoxide dismutase (38.94%) and reduced glutathione (23.84%) in animals treated with Dox. Concurrently marked increase in serum creatine kinase-MB (CKMB) activity (48.11%) as well as increase in extent of lipid peroxidation (2.55-fold) was reported. Co-treatment of TA-05 and Dox resulted in an increase in the cardiac antioxidant enzymes, decrease in serum CKMB levels and reduction in lipid peroxidation as compared to Dox-treated animals. Electron microscopic studies in Dox-treated animals revealed mitochondrial swelling, Z-band disarray, focal dilatation of smooth endoplasmic reticulum (SER) and lipid inclusions, whereas the concurrent administration of TA-05 led to a lesser degree of Dox-induced histological alterations. These findings suggest that butanolic fraction of Terminalia arjuna bark has protective effects against Dox-induced cardiotoxicity and may have potential as a cardioprotective agent. 相似文献
74.
75.
Soubhagya R. Nayak Ashwin Krishnamurthy SJ Madhan Kumar Latha V. Prabhu Bhagath Kumar Potu Sujatha D’Costa Anu Vinod Ranade 《Hand (New York, N.Y.)》2010,5(1):31-36
The superficial palmar arch (SPA) and its contributing arteries are highly variable. The palmar type of median artery (PMA)
can be involved in the formation of the SPA by replacing the superficial palmar branch of the radial artery (RA) or the ulnar
artery (UA). The present study was undertaken to investigate the presence of the PMA and its contribution in the formation
of SPA in 42 cadavers (84 upper limbs) of Indian origin. When there was a PMA, its outer diameter was measured in the carpal
tunnel. The PMA was found in 13 upper limbs (15.4%), and of these ten incidences (11.9%), the PMA took part in the formation
of SPA, and in three instances (3.5%), the PMA did not make up part of the SPA. Out of the ten cases in which the PMA contributed
to the formation of SPA, in six cases (7.1%), the PMA anastomosed with the UA; in three cases (3.5%), the PMA anastomosed
with both the UA and the RA, and in one incidence (1.1%), the PMA joined the arteria radialis indicis (deep branch of the
RA) to complete the SPA. The outer diameters of the median arteries varied between 0.8 and 2.6 mm with the mean value of 1.7 mm.
The present study concludes that the median–ulnar type of SPA was the most common type of SPA when the PMA was encountered
as a source of superficial arterial arcade of the hand, followed by the radial–median–ulnar type. The vascular patterns found
in this study are important to hand surgeons. The present study of PMA origin, course, and its contribution to the SPA will
add to the existing knowledge of the vascular anatomy of forearm and hand. 相似文献
76.
77.
Meenu Jain Shaleen Kumar Punita Lal Anu Tiwari Uday C Ghoshal Balraj Mittal 《Cancer epidemiology, biomarkers & prevention》2007,16(1):178-181
GSTM3 is involved in detoxification of carcinogens and may be important in modulating cancer susceptibility. GSTM3 genotype frequencies were determined in peripheral blood DNA of 149 esophageal cancer patients and 200 nonmalignant controls using the PCR followed by PAGE. Patients who were heterozygous carriers of GSTM3 AB genotype had an enhanced risk for developing esophageal cancer [odds ratio (OR), 2.1; 95% confidence interval (95% CI), 1.1-3.7; P = 0.01]. In males, the risk due to GSTM3 AB genotype increased further (OR, 3.4; 95% CI, 1.7-6.8; P = 0.000). Interaction of GSTM3 AB + BB and GSTM1 null genotypes marginally modulated risk (OR, 2.3; 95% CI, 1.1-3.7; P = 0.01). Association with histology (adenocarcinoma: OR, 3.4; 95% CI, 1.1-10.9; P = 0.03) and tumor site (middle third location: OR, 2.2; 95% CI, 1.1-4.4; P = 0.01; lower third location: OR, 2.6; 95% CI, 1.2-5.6; P = 0.01) was also documented. Our results suggest that GSTM3 polymorphism may influence esophageal cancer susceptibility, in particular modulating the risk for adenocarcinoma histology and tumors of the mid and lower third region. 相似文献
78.
M Heikinheimo H Jalanko J Leisti K L Kolho R Salonen H Von Koskull P Aula 《Prenatal diagnosis》1984,4(2):147-150
Concentration of pregnancy-specific beta 1-glycoprotein (SP1) was studied in second and third trimester amniotic fluid from pregnancies with various fetal developmental disorders. The material consisted of 26 cases with chromosomal disorders and 19 cases with non-chromosomal fetal malformations. The SP1 concentration was elevated in two cases of Meckel's syndrome (mean +2.7-4.0 S.D.) as well as in one case of fetal triploidy (mean +22 S.D.), while it was normal in all other 14 different fetal disorders. 相似文献
79.
80.
Bass CE Griffin G Grier M Mahadevan A Razdan RK Martin BR 《Pharmacology, biochemistry, and behavior》2002,74(1):31-40
The central cannabinoid receptor (CB(1)) antagonist, SR-141716A, has been used extensively to ascertain that cannabinoids interact with the CB(1) receptor. SR-141716A has been shown to produce effects opposite of cannabinoids when administered alone. It has been theorized that SR-141716A may act as an inverse agonist at the CB(1) receptor or by disinhibiting an endogenous cannabinoid tone. In an effort to ascertain the exact interaction between SR-141716A and the CB(1) receptor, we have conducted a structure-activity relationship study to compare CB(1) receptor affinity of SR-141716A analogs with their ability to produce an increase in locomotor activity. SR-141716A produced a significant increase in locomotor activity in mice within the first hour of administration. Twenty SR-141716A analogs from five different chemical series were also tested. Our data implicate particular regions of the SR-141716A molecule that may be involved in stimulation and depression of locomotor activity. When the K(I) of the analogs was plotted against the percent stimulation that each analog produced, it is evident that there is no correlation between the ability of the analogs to stimulate locomotor activity and their affinity for the CB(1) receptor. [35S]GTPgammaS binding data indicate that SR-141716A and five of the analogs are inverse agonists. However, none of the analogs demonstrating inverse agonism produce stimulation of locomotor activity. It is therefore concluded that the SR-141716A-induced stimulation in locomotor activity is not the result of inverse agonist activity at the CB(1) receptor or by disinhibition of an endogenous tone. 相似文献