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21.
Gonadectomized male and female rats show no preferences for the odors of conspecifics of the opposite sex and no urine-marking. Castrated males given testosterone propionate (TP) injections showed preferences for female odors over no odor as did males given estradiol benzoate (EB). Males given EB plus progesterone (P), P only, or oil (controls) showed no preferences for female odors. No group of ovariectomized females (TP, EB, EB+P, or oil injected) showed a preference for male odors over no odor. Males given TP, EB, or EB+P injections showed an increase in urine-marking while males given P or oil showed no marking. Females given TP injections showed an increase in marking but those given EB, EB+P or oil showed no marking. These results are discussed in relation to studies on the hormonal control of scent-marking in gerbils and sexual behaviour in rats.  相似文献   
22.
An intrauterine progesterone contraceptive system (IPCS) (52 mg) was inserted in 25 women with cystic endometrial hyperplasia. Among these women, 11 complained of heavy climacteric symptoms and also received an oestrogen replacement therapy consisting of conjugated oestrogens (0.625 mg/day) administered cyclically for 3 out of 4 wk. Prior to the therapy and after 6 mth of treatment, follicle stimulating hormone (FSH), luteinizing hormone (LH), prolactin (PRL), oestrone (E1) and oestradiol (E2) plasma levels were measured and endometrial histology was evaluated. In the women receiving IPCS treatment alone, there were no significant changes in FSH, LH, PRL, E1 and E2 plasma levels. However, there were remarkable changes found in their endometrial histology. In the remaining women receiving both treatments there was a sharp decrease in FSH and LH plasma levels and an increase in E1 and E2 plasma levels, while the prolactin levels remained unchanged. With the exception of two of these women, the endometrial histology changed remarkably. The endometrial morphology of the two exceptions remained unchanged. All climacteric symptoms disappeared after the administration of both IPCS and the oestrogen replacement therapy. The remarkable changes which did occur in the endometrial histology resulted in a less active glandular epithelium and stromal decidual formation, thus proving a useful effect of treatment.  相似文献   
23.
Sexually experienced male rats were used to test the attractiveness of body odors of female rats. The attractiveness of these odors varied with the estrous cycle. Odors from female rats in proestrus were the most attractive to male rats and those from female rats during the darkness hours of diestrus the least attractive. The preputial glands appeared to be the source of these odors for the male rats showed no preference for the odors of proestrous female rats that had been preputialectomized. Administration of 1 μg estrdiol benzoate (EB) for 5 days increased the attractiveness of body odors of ovariectomized rats. A higher dose of EB (5 μg) had the same effect when administered for 1 or 5 days although the increase that occurred after 3 days was not significant. A single dose of progesterone (P) (500 μg) on the other hand, decreased the attractiveness of ovariectomized female odors although no change was seen after 3 days of treatment. A single injection of P also decreased the attractiveness of odors of ovariectomized females that had received EB for 3 days. However, P failed to decrease the attractiveness of odors in ovariectomized females after preputialectomy. We conclude that the preputial glands are an important source of sex attractant odors in the female rat and that the changes in the release of these odors that occur throughout the estrous cycle and pregnancy are controlled by ovarian steroids. While estrogen acts to stimulate the production and release of these odors P appears to inhibit their release.  相似文献   
24.
目的 探讨性激素在膀胱癌发病中的意义。方法 :采用放射免疫法检测 31例男性膀胱癌患者及 2 7例同年龄正常人对照组血清中的雌二醇 (EstradiolE2 )、孕酮 (ProgesteroneP)及睾酮 (TestosteroneT)水平。结果 :男性膀胱癌患者血清E2 、P、T分别为 44.98± 2 0 .96pg ml( x±s) ,0 .37± 0 .18ng ml( x±s) ,6 .2 5± 2 .37ng ml( x±s) ,而正常对照组E2 、P、T分别为 5 6 .0 1± 13.5 0pg ml( x±s) ,1.14± 0 .37ng ml( x±s) ,5 .15± 1.37ng ml( x±s) ,两者比较膀胱癌组T明显高于对照组 (P <0 .0 5 ) ;而E2 、P明显低于对照组 (P <0 .0 5 )。结论 :膀胱癌的发生可能与性激素代谢失衡有一定的关系  相似文献   
25.
The sexual behaviour of 7 pairs of marmosets was observed during 30 minute tests for 44-68 days and blood samples were collected from females for measurement of plasma progesterone, testosterone and oestrone. Copulations occurred throughout the ovarian cycle of 24-30 days. Females used a "tongue-flicking" display both as an invitational behaviour (proceptive tongue-flicks) and during copulation (receptive tongue-flicks) most frequently during the peri-ovulatory period. Frequencies of proceptivity were correlated positively with high mean levels of testosterone and oestrone during the cycle and with a short follicular phase. Males showed significant increases in tongue-flicks, mounts and ejaculations during the peri-ovulatory phase, together with a shortened post-ejaculatory interval and increased duration of penile erection after ejaculation. A retrospective analysis showed that these changes in the males' behaviour occurred only during tests where females were proceptive and not during other tests in the peri-ovulatory period. Females refused significantly more of the males' mounting attempts during the luteal phase and a corresponding reduction in mount frequency occurred at this time. Grooming, scent-marking, olfactory inspections and some other behaviours did not alter significantly in either sex during the ovarian cycle.  相似文献   
26.
黄体酮对兔离体主动脉平滑肌张力的影响   总被引:4,自引:0,他引:4  
目的 观察黄体酮对KCl去极化引起的兔离体主动脉肌条收缩作用的影响 ,并探讨其作用与内皮细胞的关系。方法 制备家兔离体主动脉平滑肌条 ,置于灌流肌槽中 ,记录肌条的张力变化。结果 黄体酮 (5、5 0和 10 0 μmol·L- 1)使KCl量效曲线明显右移 ,最大反应压低 ,KCl的EC50 由对照 (36.4± 19.7)mmol·L- 1依次变为 (4 0 .3± 19.6)、(4 3.4± 2 0 .9)和 (5 9.0± 2 0 .1)mmol·L- 1(r =0 .94 ,P <0 .0 5 ) ;83.3μmol·L- 1黄体酮使KCl 2 5 .1mmol·L- 1预收缩胸主动脉肌条明显舒张 (P <0 .0 0 1) ;去内皮后 ,此舒张作用明显减弱。结论 黄体酮可使兔胸主动脉血管平滑肌条舒张 ,其作用可能是通过抑制血管平滑肌细胞膜上的电压依赖性钙通道 ,并与内皮细胞存在有关  相似文献   
27.
Mifeprlstone,a norethindrone, is the first synthetic effective steroid which canbind to the progesterone receptor with greater affinity than progesterone, but lacksthe agonistic effect. Its anti--progestin action results in the withdrawal of progesterone at cellular level to interrupt its biological action and can terminate early pregnancy['j. At present, the dose of mifepristone in combination with the analogue ofprostaglandin in terminating early pregnancy is 150 mg-- 200 mg and the complete…  相似文献   
28.
Objective To provide the theoretical fundation for the further clinical application of mi fepristone and anordrin compound. Materials & Methods Ribonuclease protection assay was used for the detection and quantitation of estrogen and progesterone receptor mRNAs in human decidua from the termination of early pregnancy. Three groups, each of which had 6~8 cases, were studied. Results Compared to the normal control group, estrogen and progesterone receptor mRNAs increased significantly (P<0.05) in the mifepristone group, whereas the changes in the group administrated mifepristone compound which contains anordrin were not obvious. Conclusions The result suggests that with the similar clinical effect, mifepristone compound has less side effect on the patients, thus being more suitable for the anti-ear ly pregnancy drug.  相似文献   
29.
30.
Exposure of neocortical slices to progesterone, without prior treatment with estrogen, augmented forskolin-induced cyclic AMP within 15 min. 30 nM progesterone produced approximately 1/2 the maximal effect but as little as 10 nM progesterone produced a detectable increase in cyclic AMP. When forskolin was replaced by dideoxyforskolin, an analog that does not directly stimulate adenylyl cyclase but shares many of its other actions, progesterone did not augment cyclic AMP. Progesterone also failed to affect increased cyclic AMP that followed exposure to norepinephrine or isoproterenol. The effect of progesterone upon cyclic AMP was also evident when tetrodotoxin was added to block voltage-dependent sodium channels, suggesting that intercellular communication that is dependent upon action potentials was not necessary. The effect of progesterone was at least partially blocked by antagonists of GABAA receptor action, suggesting the involvement of GABAA or GABAA-like receptors. The effect of progesterone was also not homogeneous over the neo cortex. While forskolin-stimulated cyclic AMP was augmented by progesterone in the parietal and occipital regions, it was suppressed in the frontal region. These results are envisioned as a progesterone action upon a small and perhaps compartmentalized component of the cellular cyclic AMP system, an effect that is made detectable in our whole-tissue assay by the well known ability of forskolin to potentiate many hormonal effects upon cyclic AMP.  相似文献   
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