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101.
102.
Background
Despite extensive research, the five-year survival rate of oral squamous cell carcinoma (OSCC) patients has not improved. Effective treatment of OSCC requires the identification of molecular targets and signaling pathways to design appropriate therapeutic strategies. Several genes from the mTOR signaling pathway are known to be dysregulated in a wide spectrum of cancers. However, not much is known about the involvement of this pathway in tumorigenesis of OSCC. We therefore investigated the role of the tumor suppressor genes, TSC1 and TSC2, and other members of this pathway in tumorigenesis of OSCC. 相似文献103.
L B Dain P Stein A R Krimer R H Asch E P de Fried E H Charreau M Tesone 《Fertility and sterility》1991,55(6):1093-1098
STUDY OBJECTIVE: To examine the progesterone (P) production by cultured granulosa cells and the hormonal content in the follicular fluid (FF) of ovarian-hyperstimulated women. DESIGN: Retrospective. SETTING: Private Fertility Clinic and National Research Institute. PATIENTS: Eighteen patients undergoing in vitro fertilization or gamete intrafallopian transfer programs. RESULTS: Progesterone levels Measured in the culture medium of granulosa cells decreased sixfold with culture time. Human luteinizing hormone (LH) increased P production only when basal P production was less than 1 microgram/mL. Granulosa cell P production in culture was negatively correlated with FF LH-human chorionic gonadotropin (hCG) levels. Follicular fluid follicle-stimulating hormone (FSH) levels were positively correlated with FF P and 17 beta-estradiol (E2) concentrations. Similar results were found between FF LH (hCG) and E2 levels, but there was no relationship between FF LH (hCG) and FF P values. CONCLUSION: The high dose of hCG administered during gonadotropin treatment could induce a decrease in the in vitro granulosa cell P production. 相似文献
104.
Kaplan Carolyn R. Olive David L. Sabella Vincente Asch Ricardo H. Balmaceda Jose P. Riehl Robert M. Groff Terry R. Burns William N. Schenken Robert S. 《Journal of assisted reproduction and genetics》1989,6(5):298-304
Superovulation with intrauterine insemination (SO-IUI) has been suggested as an alternative to gamete intrafallopian transfer (GIFT), despite the absence of controlled or comparative trials. We retrospectively analyzed all GIFT and SO-IUI cycles performed concurrently from January 1985 to August of 1987 at a single university center. Pregnancy rates were significantly better for GIFT than SO-IUI (P<0.001), with an odds ratio of 3.25 (P=0.001). Stepwise multiple logistic regression identifield factors that correlate with pregnancy: absence of endometriosis (P=0.05), infertility<3 years' duration (P=0.002), TMS 30×106 (P=0.005), and treatment with GIFT rather than SO-IUI (P=0.001). These data give a first approximation of the increased efficacy of GIFT versus SO-IUI and provide valuable insight into significant confounding variables to be considered when planning a randomized, prospective trial to evaluate these techniques. 相似文献
105.
F J Rojas A T La T Ord P Patrizio J P Balmaceda S J Silber R H Asch 《Fertility and sterility》1992,58(5):1000-1005
OBJECTIVES: To assess the ability of sperm aspirated from the epididymis of men with congenital absence of the vas deferens to penetrate zona-free hamster oocytes. To directly compare the performance of human epididymal sperm in the zona-free hamster oocyte sperm penetration assay (SPA) with the results of human in vitro fertilization (IVF). DESIGN: Sperm penetration assay was carried out with epididymal sperm retrieved microsurgically, and with ejaculated sperm obtained from fertile donors (internal controls). For direct comparison, SPA was performed with the same epididymal sperm sample used for IVF. PATIENTS, PARTICIPANTS: Men with congenital absence of the vas deferens undergoing sperm aspiration as part of their infertility treatment and control donors who provided ejaculated sperm. RESULTS: Epididymal sperm penetrated SPA with a score of 0% to 30%. The SPA scores for internal controls using ejaculated sperm was 30% to 71%. Linear regression analysis of the association between penetration scores in SPA and fertilization rate in IVF indicated a positive correlation that was highly significative. CONCLUSIONS: These findings using SPA confirm previous reports on the fertilizing potential of human epididymal sperm and its ability to produce normal pregnancies. The good correlation between SPA and human IVF using epididymal sperm suggest that SPA is an excellent bioassay to test laboratory experimental conditions for improving fertilizing capacity of human epididymal sperm. 相似文献
106.
107.
Results of tubal embryo transfer in premature ovarian failure 总被引:1,自引:0,他引:1
D A Rotsztejn J Remohi L N Weckstein T Ord D L Moyer J P Balmaceda R H Asch 《Fertility and sterility》1990,54(2):348-350
The transfer of embryos generated in vitro to the fallopian tubes in 11 cases of premature ovarian failure resulted in 9 clinical pregnancies. This approach may have theoretical advantages over GIFT and IVF-ET in agonadal patients. 相似文献
108.
Force generated by human sperm correlated to velocity and determined using a laser generated optical trap 总被引:3,自引:0,他引:3
The development of the single beam gradient force optical trap has made it possible to manipulate cells solely by laser light. A continuous wave Nd:YAG (1.06 microns) laser beam was directed into a conventional microscope and focused onto the viewing plane by the objective lens. The laser beam power at which human sperm were released from the trap was measured and correlated to the sperm's linear velocity before trapping. The mean trapping power readings for slow, medium, and fast motile sperm were 57, 73, and 84 mW, respectively. The analysis of measurements over the total population demonstrated that zig-zag motile sperm had significantly higher mean power readings when compared with straight motile sperm with similar mean linear velocities. In two cases, specimens required significantly less trapping power when the measurements were repeated 24 hours later. 相似文献
109.
Carriage of Haemophilus influenzae and Streptococcus pneumoniae in healthy Chinese and Vietnamese children in Hong Kong 总被引:1,自引:0,他引:1
RYT Sung JM Ling SM Fung SJ Oppenheimer DW Crook JTF Lau AFB Cheng 《Acta paediatrica (Oslo, Norway : 1992)》1995,84(11):1262-1267
Nasopharyngeal carriage of Haemophilus influenzae and Streptococcus pneumoniae was studied in 621 healthy Chinese children and 300 healthy Vietnamese children aged from 2 months to 5 years in Hong Kong. The carriage rate of H, influenzae type b in Vietnamese children was 1.3% (CI 0.04-2.63%); it was zero in Chinese. The carriage rate of non-typable H. influenzae was 5.8% (CI 1.4-7.6%) in Chinese and 65.4% (CI 58.9-69.8%) in Vietnamese. The carriage rates of S. pneumoniae were 10.8% (CI 8.3-13.2%) and 55.7% (CI 50.1-61.3%) in Chinese and Vietnamese children, respectively. Univariate and multivariate logistic regression analyses were performed to search for factors associated with differences in carriage rates of both H. influenzae and S. pneumoniae between Chinese and Vietnamese children. Although older age, smaller living area and parental smoking were associated with higher carriage rates, these could not explain the remarkably low carriage rates of both bacteria in Chinese children. 相似文献
110.
SF Slaney AO Wilkie MC Hirst R Charlton M McKinley J Pointon Z Christodoulou SM Huson KE Davies 《Archives of disease in childhood》1995,72(1):33-37
Fragile X syndrome is the most common inherited cause of mental retardation. Early diagnosis is important not only for appropriate management of individuals but also to identify carriers who are unaware of their high risk of having an affected child. The disorder is associated with a cytogenetically visible fragile site (FRAXA) at Xq27.3, caused by amplification of a (CGG)n repeat sequence within the gene at this locus designated FMR1. Clinical and molecular studies have been undertaken to screen for fragile X syndrome in 154 children with moderate and severe learning difficulties of previously unknown origin. Southern blot analysis of peripheral blood showed the characteristic abnormally large (CGG)n repeat sequence associated with fragile X syndrome in four of the 154 children. The findings were confirmed by cytogenetic observation of the fragile site and by further molecular studies. The families of the affected children were offered genetic counselling and DNA tests to determine their carrier status. These findings show that there are still unrecognised cases of fragile X syndrome. Given the difficulty of making a clinical diagnosis and the implications for families when the diagnosis is missed, screening in high risk populations may be justified. The issues involved in screening all children in special schools for fragile X syndrome are discussed. 相似文献