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31.
目的探讨不孕不育及自发流产与染色体核型异常的关系,指导临床对这些疾病的诊断。方法采集922例生殖异常患者外周静脉血,进行淋巴细胞培养,常规方法收获细胞,低渗、固定、制片、经G显带处理、镜检,进行观察研究。结果922例患者共检出异常核型66例,总检出率7.16%。其中,易位21例,倒位21例,克氏综合征18例,X-三体综合征2例,Turner综合征伴X染色体缺失1例,Y染色体缺失1例,环状21号染色体1例,额外标记染色体1例,及常见染色体多态性大Y染色体63例,发生率13.35%。结论染色体异常是导致不孕不育及自发流产的重要原因之一,对生殖异常患者进行染色体检查可为临床诊断和优生优育提供依据。  相似文献   
32.
目的探讨柳州地区籍女性新生儿黄疸儿G6PD基因突变类型与其临床表现特点之间的关系.方法采用基因芯片技术检测了7例柳州地区籍女性新生儿黄疸儿的G6PD基因突变类型,并对其临床表现特点进行分析.结果 (1)7例女患儿G6PD基因突变共检出4种类型,包括G1388A、A95G、G1376T及G392T,其中5例为杂合子.(2)G6PD酶学检查5例表现为中间型,且临床黄疸症状较轻,治疗效果好.结论柳州地区籍女性新生儿黄疸儿的G6PD基因突变类型多见G1388A、A95G、G1376T突变,以杂合子改变占多数.  相似文献   
33.
Dieting and stress are important in the etiology and maintenance of eating disorders, and dieting strongly predicts stress-induced overeating in humans. We hypothesized that caloric restriction and stress interact in a unique manner to promote binge eating. To test this hypothesis, a group of young female rats were cycled through a restriction period (4 days of 66% of control food intake) followed by 6 days of free feeding prior to being stressed by acute foot shock. After three of these cycles, the food intake of rats exposed only to restriction (R), or only to stress (S), did not differ from controls. However, R+S rats that were restricted and refed, despite normal body weight and food intake after free feeding, engaged in a powerful bout of hyperphagia when stressed (Experiment 1). The R + S effect was replicated in an older group of rats (Experiment 2). The hyperphagia was characteristically binge-like, it constituted a 40% selective increase in highly palatable (HP) food (P < .001) over a discrete period of time (within 24 h post-stress), and reflected feeding for reward (higher HP:chow ratio) over metabolic need as occurred after restriction (higher chow:HP ratio). Subsequent experiments revealed that binge eating did not occur if only chow was available (Experiment 3) or if restriction-refeeding (R-R) did not proximally precede stress (Experiment 4). Experiment 5 revealed that a history of R-R cycles followed by only one stress episode was sufficient to increase intake to 53% above controls as early as 2 h after stress (P < .001). This animal model of binge eating should facilitate investigations into the neurochemical changes induced by dieting and environmental stress to produce disordered eating and provide a preclinical tool to test preventive strategies and treatments more relevant to bulimia nervosa, multiple cases of binge eating disorder (BED) and binge-purge type anorexia nervosa.  相似文献   
34.
Effects of aging on estrous cycles and LH release in response to luteinizing hormone releasing hormone (LHRH), castration, and estradiol benzoate were studied in the female golden hamster (Mesocricetus auratus). About 80% to 90% of female golden hamsters still cycled regularly when reaching 19–22 months of age. However, some animals showed age-induced irregularity of the estrous cycle which included an interruption of complete absence of estrous vaginal discharge. Young female hamsters (3–5 months) had significantly (p<0.01) higher basal LH concentration than old animals (19–22 months) in the morning of each stage of estrous cycle. LHRH elicited about 20–30 fold increase in serum LH concentrations in both young and old hamsters. No significant difference in LH release was observed between young and old hamsters in response to LHRH. In acyclic hamsters, the peak of LH release in response to LHRH was delayed. LHRH-induced LH release was greater in the morning of proestrus than during diestrus in both young and old hamsters. LH increase was significantly greater in the young than in old hamsters on the 13th and 15th day after castration. However, positive feedback stimulation of LH release by estradiol benzoate was the same in both young and old hamsters. These results indicate that in the female hamster, LH response to acute stimuli such as LHRH and estrogens is the same in the young as in the old animal and that circulating basal LH concentration may decrease or its degradation or clearance may increase during the aging process in female golden hamsters. Irregularity of estrous cycles in aging hamsters may be related to delayed responsiveness of pituitary LH to LHRH stimulation.  相似文献   
35.
不孕及反复流产患者血清抗心磷脂抗体的检测   总被引:8,自引:0,他引:8  
目的检测不孕及反复流产患者血清中的抗心磷脂抗体(ACA),探讨ACA的临床意义.方法应用酶联免疫吸附(ELISA)法检测105例原发或继发不孕患者(不孕组)、171例反复流产或有胚胎停育史患者(流产组)及40例正常对照组血清中的IgG、IgM及IgA-ACA 3种抗体.结果不孕组ACA总阳性率为44.76%,流产组为35.09%,均显著高于对照组(P<0,01).不孕组及流产组的单纯IgG阳性率亦明显高于对照组(P<0.05);而两组的单纯IgM阳性率与对照组相比,差异均无显著性意义(P>0.05).结论ACA是导致不孕及反复流产的免疫学因素之一,IgG型的ACA比IgM型的更具临床意义  相似文献   
36.
The central effect of oxytocin (OT) on the aggressive behavior of lactating rats was studied. Female rats are more aggressive than nonlactating resident females, vigorously attacking conspecific intruder male or females. This behavior is considered important for pup protection against infanticide. The present work aimed to test the effects on maternal aggressive behavior of OT infused into the central amygdaloid nucleus (CeM) or bed nucleus of stria terminalis (BNST). The surgeries for bilateral cannula implantation were performed between the 2nd and 4th postpartum day. Three days after the surgery, saline or OT was infused and 5 min later a male intruder was placed in the home-cage and the behaviors were videotaped for 10 min. The frequency of the aggressive behaviors and the duration of locomotion during the aggressive behavior test were measured. The latency to retrieve the pups was also evaluated. The results showed that OT injected into CeM (10 and 20 ng/nucleus) decreased frequency of biting and frontal attack while in the BNST (10 and 20 ng/nucleus) decreased the frequency of biting. No significant change on retrieval activity was detected. OT in CeM and BNST has an inhibitory effect on the aggressive behavior of lactating female rats.  相似文献   
37.
Objectives: To look for possible association between past history of ovulation induction and age at menopause. Design: Women attending our postmenopausal outpatient clinic were asked to fill questionnaires with demographic data, obstetrical history (including treatment for infertility), and medical details related to menopause. Patients: The study group (n=31) consisted of women with a history of ovulation induction, and a control group (n=200) included women who did not experience such intervention. Results: The age at the final menstrual bleeding was 46.4±5 in the study group, and 50±4 for the control group (P<0.001). This difference was most prominent for women who had induction of ovulation prior to age 35 years: they entered menopause at age 43.8±5 years. Smoking had a weak effect on the age at menopause (48.5±4 for current, vs. 49.9±4 for non- or past-smokers; P<0.03). Conclusions: This retrospective and preliminary study raises the question whether hormonal manipulations and ovarian over-stimulation during fertility treatments could be a risk factor for premature menopause.  相似文献   
38.
Chronic cocaine exposure during critical periods of development induces short- and long-term effects. During the pubertal period, the hypothalamic–pituitary–gonadal (HPG) axis undergoes many dynamic changes. The present study investigated whether chronic periadolescent cocaine alters reproductive maturity in the rat. Sixty female Long–Evans hooded rats were randomly assigned to one of three conditions (20 mg cocaine/kg/day, saline injected and uninjected), for dosing from postnatal day 21 (P21) through P60. Several indicators of reproductive maturation and functioning were assessed during and following treatment. Cocaine exposure had no effect on the onset of puberty or on the date of first ovulation. The number of proestrus–estrus transitions was significantly lower in cocaine-exposed females compared to uninjected females, but not compared to saline-injected controls. This reduction was observed during exposure to cocaine, as well as after the cessation of injections. During the dosing period, cocaine-exposed rats also exhibited a greater number of cycles that had no clear P–E transition than did UN subjects; this effect disappeared once injections stopped. These alterations suggest immediate, and possibly persisting, alterations in the control of ovulation after chronic cocaine exposure throughout adolescence. Interestingly, during the injection period, the saline-injected females had a significantly greater number of diestrus days compared to uninjected and cocaine-injected animals, as well as a lower proportion of regular 4- and 5-day cycles. These differences disappeared once injections stopped. These results suggest a stress-induced irregularity of the estrous cycle, possibly attenuated by cocaine and recoverable after exposure. The present findings indicate that the HPG axis is susceptible to short-term, and possibly to long-term, alterations induced by cocaine exposure throughout the adolescent period.  相似文献   
39.
本文对60名女性海洛因依赖者与54名健康女性的月经、生育等女性生理机能和性心理及性行为进行调查分析。发现女性海洛因依赖者月经异常率为95.0%,显著高于对照组6.8%(P<0.001);海洛因对性欲和性行为影响明显,吸注海洛因成瘾后,35.0%性欲减退,58.3%性欲消失;性行为方式:吸毒前96.7%以性交为主,吸毒成瘾后仅15.0%以性交为主(P<0.001),85%以非性交接触为主;海洛因成瘾后性能力明显障碍,性交次数由吸毒前平均4.9±1.6次/周减少至平均0.4±0.2次/周(P<0.01)。结果表明:海洛因对女性生理机能和心理卫生具有明显损害作用。  相似文献   
40.
Neural transection of the dorsal extrahypothalamic descending afferents by means of an L-shaped Halász knife at the anterior commissure (anterior roof deafferentation. ARD) markedly potentiated the display of lordosis and soliciting behaviors. Bilateral lesions of the ventromedial hypothalamus (VMH) attenuated lordotic activity in the ARD sham females but not in the ARD females. In contrast, the lesions in the pontine central gray concurrently with ARD effectively inhibited the display of lordosis but not soliciting behaviors. These results suggest that the VMH may not be a primary focus of the dorsal extrahypothalamic inhibitory influence on lordosis. The influence of this inhibitory system seems to be dominant in regulating the expression of lordosis behavior, compared to that of the hypothalamic lordosis facilitating system. Furthermore, the dorsal extrahypothalamic inhibitors influence which could be removed by ARD must be modified by the neural mechanism in the lower brain stem in which the pontine central gray may be actively involved.  相似文献   
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