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31.
多囊卵巢综合征高雄激素血症患者瘦素水平的检测及评价   总被引:1,自引:0,他引:1  
目的探讨多囊卵巢综合征高雄激素血症进行患者瘦素(Leptin)水平及其与睾酮(T)、体重指数(BMI)的关系.方法采用放射免疫分析法(RIA)检测53例PCOS患者血清瘦素水平,其中非肥胖组PCOS患者36例,正常对照30例;肥胖组PCOS患者17例,正常对照20例.结果肥胖组及非肥胖组PCOS高雄激素血症患者血清瘦素水平均明显高于相当体重指数的正常对照组,有显著差异(p均<0.01);两组瘦素水平分别与其睾酮水平进行相关性分析,均显著正相关(r=0.51,p<0.01和r=0.58,p<0.01);非肥胖组PCOS患者血清瘦素水平与其BMI相关分析显示,无相关性;肥胖组PCOS患者血清瘦素水平与其BMI进行相关分析,显著正相关(p=0.56,p<0.01).结论高瘦素血症是PCOS患者的内分泌特征之一,PCOS高雄激素血症的形成与高瘦素水平有关;超重或肥胖的PCOS高雄激素血症患者存在瘦素抵抗现象.  相似文献   
32.
Hamster pups were tested for an odor preference every day from 1-16 days of age with shavings from their home cage and with clean wood shavings. The hamster pups showed a clear preference for their home cage shavings by 8 days of age. They were then tested for preferences with other odor combinations. Tests for preference with other odor pairs indicate that this preference is due to a change in the hamsters rather than a change in the stimulus. In these tests the hamster pups did not demonstrate a preference for their home shavings over shavings in which a nonlactating female had lived. Further tests will have to be done to determine how specific the hamster pup's olfactory preferences are.  相似文献   
33.
Androgen is associated with the expression of male-typical behavior, including aggressive behavior, but high levels of androgen may be incompatible with other behavioral systems, such as paternal care. In a variety of species of birds that display paternal care, testosterone (T) levels in males are maintained at low levels, and these levels rise only in response to direct agonistic challenges. This idea has not been thoroughly studied in mammals with biparental care, and we exposed male marmosets (Callithrix kuhlii), a monogamous and biparental primate to aggressive interactions with unfamiliar intruders. Urinary levels of T and cortisol (CORT) were monitored prior to and following these interactions. Baseline T was not correlated with variation in aggression in either residents or intruders, and CORT was not affected by the encounters. However, males responded to an encounter with male intruders with changes in T that correlated with the level of aggression displayed by the resident male during the trial. Encounters with male intruders that elicited high frequencies of aggressive displays by the male resident were associated with increased T 2-6 h and 24 h following the encounter, and encounters that had few aggressive displays resulted in no change or a decrease in T concentrations. Intruders did not demonstrate a significant relationship between T and aggression. Thus, the magnitude of the hormonal response is dependent on the intensity of aggression during a male-male encounter, suggesting that elevated androgens are likely to be a consequence, rather than a cause, of aggressive interactions in marmosets.  相似文献   
34.
The bulbocavernosus (BC) reflex, produced in the BC motor nerve in response to electrical stimulation of the contralateral pudendal sensory nerve, was investigated in intact, castrated, and testosterone-treated castrated male rats under urethane anesthesia. No significant group differences in the reflex latency, sensory or motor conduction velocity, or central delay were observed. A conditioning pulse to the pudendal sensory nerve caused suppression of the averaged antidromic field potential recorded in the contralateral spinal nucleus of the bulbocavernosus (SNB) after stimulation of the SNB axons in the BC motor nerve. The suppression occurred at 6- to 35-ms intervals between shocks to pudendal sensory nerve and BC motor nerve, and was markedly smaller in castrated males than in the other two groups. In contrast, a conditioning pulse to the contralateral BC motor nerve had no effect on the SNB antidromic field potential. These results indicate that androgen modulates the efficacy of synaptic transmission onto SNB motoneurons or other neurons involved in the BC reflex.  相似文献   
35.
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   
36.
Steroid hormones regulate sexual behavior primarily by slow, genomically mediated effects. These effects are realized, in part, by enhancing the processing of relevant sensory stimuli, altering the synthesis, release, and/or receptors for neurotransmitters in integrative areas, and increasing the responsiveness of appropriate motor outputs. Dopamine has facilitative effects on sexual motivation, copulatory proficiency, and genital reflexes. Dopamine in the nigrostriatal tract influences motor activity; in the mesolimbic tract it activates numerous motivated behaviors, including copulation; in the medial preoptic area (MPOA) it controls genital reflexes, copulatory patterns, and specifically sexual motivation. Testosterone increases nitric oxide synthase in the MPOA; nitric oxide increases basal and female-stimulated dopamine release, which in turn facilitates copulation and genital reflexes. Serotonin (5-HT) is primarily inhibitory, although stimulation of 5-HT(2C) receptors increases erections and inhibits ejaculation, whereas stimulation of 5-HT(1A) receptors has the opposite effects: facilitation of ejaculation and, in some circumstances, inhibition of erection. 5-HT is released in the anterior lateral hypothalamus at the time of ejaculation. Microinjections of selective serotonin reuptake inhibitors there delay the onset of copulation and delay ejaculation after copulation begins. One means for this inhibition is a decrease in dopamine release in the mesolimbic tract.  相似文献   
37.
Previous work has shown that rate of extinction of a conditioned taste aversion is affected by concurrent levels of testosterone in adult rats. In the present study, castrated male and female adult rates were given either oil or testosterone during acquisition of the conditioned taste aversion and then either oil or testosterone during extinction. The males and females that received testosterone during the extinction of the aversion showed the slower, masculine rate of extinction regardless of the type of injections they received during acquisition. Conversely, the animals that received oil during extinction showed the faster, feminine rate of extinction regardless of the type of injection during acquisition. In light of these findings, a number of alternative behavioral changes that could account for the effect of testosterone on the rate of extinction were evaluated.  相似文献   
38.
Self-grooming in response to the odors of conspecifics is a form of olfactory communication among meadow voles. The amount of time meadow voles spend self-grooming when they encounter the odors of conspecifics varies seasonally, with males targeting the odors of reproductively active females only during the breeding season. Other odor related behaviors in male voles such as odor preferences for conspecifics and the attractiveness of their odors to conspecifics vary seasonally as well. For male meadow voles, these behaviors are mediated by seasonal variations in testosterone (T) and prolactin (PRL) titers. The objective of this study was to determine whether seasonal differences in the amount of time male meadow voles self-groom in response to odors of conspecifics are mediated by seasonal rhythms in their circulating T and PRL titers. We tested the hypothesis that high titers of both T and PRL are necessary for reproductively active (long-photoperiod; LP) males and sufficient for reproductively quiescent (short-photoperiod; SP) male voles to spend more time self-grooming in response to odors of LP females than to those of other conspecifics. Results of this study demonstrate that high titers of PRL and T are necessary for LP male meadow vole to self-groom more in response to odors of LP females as compared to those of other conspecifics, but were not sufficient to induce SP males to preferentially self-groom to odors of LP females. The endocrine control of self-grooming by LP males appears to depend upon high titers of both PRL and T, which matches the endocrine mediation of other odor related behaviors in male voles. In contrast, the endocrine tissues that underlie self-grooming in SP male meadow voles appear to be refractory to the effects of LP-equivalent titers of PRL and T.  相似文献   
39.
目的揭示老龄人群前列腺增生的发病现状及血清睾酮水平的变化规律.方法以一汽集团50岁以上男性为研究对象,另设2组年龄对照,均行直肠指诊、经腹前列腺超声检查、放免技术测定血清睾酮与皮质醇含量.结果(1)50岁以上人群中BPH发现率,直肠指诊诊断率为60.05%,经腹超声诊断率为69.57%,并且随增龄明显增高;(2)血清睾酮含量随增龄下降,二者间呈明显的负相关关系(r=-0.45,P<0.0001);(3)前列腺体积与血清睾酮含量呈显著的负相关关系(r=-0.224,P<0.001).结论在50岁以上人群中BPH的发现率超过60%,并发现BPH的发病可能与血清睾酮含量下降有关.  相似文献   
40.
目的 观察国产十一酸睾酮治疗慢性再生障碍性贫血的疗效及其副作用。分析患者雄激素治疗的疗效与骨髓增生程度的关系。方法 将 60例慢性再生障碍性贫血患者单纯随机分为两组 ,十一酸睾酮治疗组 3 0例 ,肌注十一酸睾酮 ,2 5 0mg/次 ,1次 /周 ,血红蛋白正常后 ,改为 1次 / 2周 ,2个月后 1次 / 4周。康力龙对照组 3 0例 ,口服康力龙 2mg,3次 /d。两组患者均按辨证分型给以中药汤剂治疗。观察治疗前后患者骨髓增生程度的变化及副作用。结果 治疗组和对照组有效率分别为 76 7%和 73 3 % (P >0 0 5 ) ,而肝功能损害率分别为0 %和 2 0 0 % ( ,P <0 0 5 ) ,声音变粗分别为 5 6 7%和 2 0 0 % (P <0 0 0 5 ) ,毛发增多分别为 5 6 7%和 3 0 0 %(P <0 0 5 ) ,痤疮发生率分别为 4 6 7%和 3 6 7% (P >0 0 5 ) ,女性闭经发生率分别为 10 0 0 %和 3 5 3 % (P<0 0 0 5 )。本组 60例患者骨髓增生程度治疗前后无明显变化 (P >0 0 5 ) ,雄激素治疗疗效与骨髓增生程度无明显相关 (Hc=5 5 9,P >0 0 5 )。结论 十一酸睾酮是一种安全、有效的雄激素制剂 ,且肝功能损害率极低 ,值得在临床推广应用。雄激素治疗有效的病例其造血功能的恢复可能是残存造血岛的代偿性造血功能增加的结果 ,而非骨髓造血的普遍恢复  相似文献   
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