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21.
实验性精索静脉曲张大鼠血清及睾内睾酮的变化 总被引:5,自引:0,他引:5
目的:研究精索静脉曲张(VC)大鼠模型对血清T和睾丸内T的影响。方法:通过部分结扎左肾静脉建立SD大鼠VC模型20只;假手术组SD大鼠20只为对照组。模型建立后4、8周取静脉血,并取部分睾丸组织匀浆提取上清液,放免法测定血清及睾丸内T浓度。结果:血清T:实验组4、8周与同期对照组相比有下降趋势,但没有统计学意义。双侧睾丸内T水平:实验组4周与对照组4周相比下降,但无统计学意义(P>0.05);实验组8周与对照组8周相比下降,具有统计学意义(P<0.01)。结论:在8周内实验性大鼠VC并没有引起血清T的降低,但可以导致双侧睾丸内T降低。 相似文献
22.
Arne Popma Robert Vermeiren Charlotte A M L Geluk Thomas Rinne Wim van den Brink Dirk L Knol Lucres M C Jansen Herman van Engeland Theo A H Doreleijers 《Neuropsychopharmacology》2007,61(3):405-411
BACKGROUND: In animals, strong evidence exists for an association between testosterone and aggression. In humans, and particularly in children and adolescents, findings have been less consistent. Previous research has suggested that this may partly be due to moderating effects of other factors, e.g., hormones. This study aims to investigate the moderating effect of cortisol on the relationship between testosterone and subtypes of aggression in delinquent male adolescents. METHODS: Participants were 103 boys (mean age 13.7) referred to a delinquency diversion program. Testosterone and cortisol levels were determined from saliva samples collected during resting conditions and related to self-report scores on overt and covert aggression. RESULTS: Linear regression analyses revealed a significant interaction between cortisol and testosterone in relation to overt aggression, with a significant positive relationship between testosterone and overt aggression in subjects with low cortisol levels but not in subjects with high cortisol levels. Using the same model for covert aggression, no significant effects of testosterone, cortisol, or testosterone x cortisol interaction were found. CONCLUSIONS: These results indicate a moderating effect of cortisol on the relationship between testosterone and overt aggression in delinquent male adolescents. Implications and directions for future research are discussed. 相似文献
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Mature (60-65 day old) male Sprague-Dawley rats received a single intraperitoneal injection of ethylene dimethane sulphonate (EDS; 100 mg/kg) and were subsequently killed at various times from day 2 to day 40 post-treatment. Testes were removed from these animals and age-matched controls and utilized either for light and electron microscopical analyses or for in-vitro assessment of Leydig cell function. Interstitial cells were prepared by collagenase digestion and used to measure 125I-labelled human chorionic gonadotrophin (hCG) binding capacity and androgen production in the presence or absence of hCG or dibutyryl cyclic AMP (dbcAMP). At day 2 after EDS treatment, 125I-labelled hCG binding capacity was reduced to 10% of control values, while the production of testosterone and 5 alpha-androstane-3 alpha, 17 beta-diol (adiol) were non-detectable. Histological observations confirmed the lack of identifiable Leydig cells at day 2-16 after EDS treatment. Between days 24 and 40 post-treatment, Leydig cell regeneration occurred, as indicated by a rise in 125I-labelled hCG binding capacity, increased androgen production and the presence of histologically identifiable Leydig cells. A pattern of adiol production similar to that seen in the immature rat during Leydig cell development was observed with peak synthesis occurring at day 30 post-treatment. Adiol production fell to barely detectable levels by day 36 and remained low at day 40. It is concluded that the steroidogenic pattern of regenerating Leydig cells in the EDS-treated animal is similar to that of developing Leydig cells in the immature animal. 相似文献
25.
Kelvin L Chou Maria L Moro-De-Casillas Melissa M Amick Leora L Borek Joseph H Friedman 《Movement disorders》2007,22(3):411-414
We examined the relationship between testosterone levels, violent dreams, and REM sleep behavior disorder (RBD) in 31 men with Parkinson's disease (PD): 12 with clinical RBD and 19 without. All PD patients with clinical RBD experienced violent dreams, but none of the 19 non-RBD patients reported violent dreams. While dream content appears to be more aggressive in PD patients with clinical RBD, the presence of violent dreams or clinical RBD is not associated with testosterone levels in men with PD. 相似文献
26.
丙酸睾丸酮加强米非司酮终止50~68天早孕的研究 总被引:7,自引:1,他引:6
为探讨丙酸睾丸酮(简称丙睾)加强米非司酮终止50~68天早孕的作用,本文以68例丙睾、米非司酮、卡孕栓(PG05)药物流产为加丙睾组,30例米非司酮、卡孕栓药物流产为对照组,比较其临床效果及药效机制。临床两组间比较,加丙睾组完全流产率95.59%,对照组为76.67%,明显高于对照组(P<0.01),加丙睾组流产后出血天数为11.17天,对照组15.39天,少于对照组(P<0.05)。从流产物病理及组化改变上观察,对照组有绒毛水肿、滋养层细胞变性、坏死,周围有糖蛋白包绕,蜕膜轻度坏死。加丙睾组除有上述绒毛病变外,突出的改变是蜕膜细胞连同滋养层柱细胞大量坏死,残存的蜕膜细胞间的胶原纤维肿胀、变性,并有网状纤维破坏。结果显示序贯应用该三种药,对终止50~68天早孕确有高效。并皆作用于受体,系分子水平药物,有广阔发展前景。 相似文献
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Testosterone, administered in the form of an inclusion complex with 2-hydroxypropyl--cyclodextrin by subcutaneous injection, enters the circulation in a manner markedly similar to the natural episodic release by the testes. The effects of a regimen of once-a-day administration of complexed testosterone to adult (castrated or intact) rats and to senescent (intact) rats were investigated. Although this procedure left the castrated animals with concentrations of circulatory hormone far below physiological levels for much of the day, a significant improvement in androgen-sensitive behavior and physiology was obtained. Furthermore, the testosterone effects were more pronounced when high doses were used periodically rather than when the same total amount of testosterone was equally divided among doses. The same supplementation to intact rats intensified androgen-sensitive behavior and physiology over normal levels. In senescent rats uniform pulses of the testosterone complex also improved behavior and physiology. Specifically, spermatogenesis was stimulated and, notably, the treatment increased muscle weight without substantial enlargement of the prostate. Since the testosterone–cyclodextrin complex also can be effectively administered as a sublingual tablet, the data suggest that similar regimens may be recommended for elderly men suffering from decreases in muscle mass. 相似文献
29.
Testosterone inhibits immunoglobulin production by human peripheral blood mononuclear cells
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We studied the in vitro effect of testosterone on spontaneous immunoglobulin production by human peripheral blood mononuclear cells (PBMC). Testosterone inhibited IgG and IgM production by PBMC both from males and females. The inhibitory effect of testosterone was revealed at doses more than 1 nm, increased dose-dependently, and reached a plateau at 100 nm. At doses <1000 nm, testosterone did not reduce cell viability. Testosterone treatment reduced IgG production by 59.0% and that of IgM by 61.3% compared with control. Immunoglobulin production by B cells was also suppressed by testosterone, though the magnitude of the suppressive effect on B cells was lower than that on whole PBMC; testosterone-induced decrease of IgG production compared with control was 26.9% and that of IgM was 24.9%. Exogenous IL-6 partially restored the impaired immunoglobulin production of testosterone-treated PBMC; IgG production in testosterone culture was increased by IL-6 from 35.6% to 66.5% of control and that of IgM was also increased from 38.9% to 71.2%, respectively. Testosterone treatment reduced IL-6 production of monocytes by 78.4% compared with control, but neither affected that of T cells or B cells. These results suggest that testosterone may suppress immunoglobulin production of human PBMC directly by inhibiting B cell activity and indirectly by reducing IL-6 production of monocytes. It is thus indicated that this hormone may have protective and therapeutic effects on human autoimmune diseases. 相似文献
30.
Oestrogen-induced suppression of collagen arthritis; 17 beta-oestradiol is therapeutically active in normal and castrated F1 hybrid mice of both sexes.
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The F1 hybrid mouse strain, from B10Q and DBA/1 parentals (the QD strain), is highly susceptible to induction of type II collagen-induced arthritis, an experimental model for rheumatoid arthritis. Males are more susceptible than females. Oophorectomy enhances susceptibility to arthritis and treatment with physiological doses of 17 beta-oestradiol (E2) suppresses disease. E2 treatment lowers the incidence of arthritis also in non-castrated and castrated males, showing that the anti-arthritic effect by oestrogen is not dependent on either sex hormone imprinting effects or interference with male sex hormones. Testosterone treatment of normal females, but not of castrated females, exaggerated development of the disease. In the testosterone-treated normal females, the oestrogen effect on vaginal smear was abolished and ovarian weight decreased, suggesting that the testosterone-mediated enhancing effect is caused by inhibition of ovarian oestrogen production. The crucial importance of oestrogens for the development of arthritis is focused on the effectiveness of treatment with gestation-related doses of E2 of normal, non-castrated females. 相似文献