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231.
Galanin (GAL) has been implicated in modulating anxiety, although a precise role remains unclear. Previous studies revealed anxiolytic effects, anxiogenic effects, or no effect, depending on the test, brain region, route of drug administration and context. We have shown previously that microinjection of the GAL antagonist M40 into central amygdala blocked an anxiolytic response to acute stress on the elevated plus maze when rats were pretreated with yohimbine, suggesting an anxiolytic effect of GAL. By contrast, we also showed that microinjection of M40 into the lateral bed nucleus of the stria terminalis attenuated anxiety-like behavioral responses to stress on the plus maze and social interaction tests, implying an anxiogenic effect for GAL. The behavioral response to stress on both these tests is a reduction of an ongoing behavior (open-arm exploration or social interaction, respectively). To better understand the anxiety-modulating role of GAL, it is also important to ascertain its effect on a response that represents an activation rather than suppression of behavior. Thus, in this study, we investigated an active behavioral response to acute stress in rats, the shock-probe defensive burying response. Bilateral microinjections of M40 into lateral septum (LS), a region important to this response and innervated by GAL, dose-dependently decreased burying without affecting immobility. No change was seen in hindpaw withdrawal latency on a thermosensitivity assay, suggesting that the reduction in burying behavior was not attributable to changes in cutaneous pain sensitivity. These results indicate that in LS, GAL facilitates the active anxiety-like behavioral response on the defensive burying test, similar to its facilitatory effect on anxiety-like stress-induced suppression of behavior in the lateral bed nucleus. These results highlight the fact that, rather than a unified system-like role in modulating anxiety, the effects of GAL can be either facilitating or attenuating, and are region-specific, context-specific and response-specific.  相似文献   
232.
Contemporary women experience more menstrual cycles than their predecessors, and their menstrual patterns are modified by contraceptives. Amenorrhea is one side effect that has recently been advocated as desirable. This qualitative study investigated Brazilian women's views regarding the suppression of menstruation using hormones. Data were collected through eight focus groups, following a semistructured guideline. Sixty-four women, 21-51 years old, all menstruating regularly and all of whom had already initiated sexual activity and had no perceived infertility participated. Discussions were recorded, transcribed and entered into the computer, using the Ethnograph V 5.0 software to aggregate similar patterns. Thematic content analysis revealed that menstruation and amenorrhea were both seen with ambiguity. Although regarded as a nuisance, menstruation was associated with femaleness, youth, fertility and health. Most women, although they would like to be free from menstruation, feared negative consequences of induced amenorrhea and even regarded the proposition as a male intrusion into what they consider a natural female condition.  相似文献   
233.
The objectives of this study were to assess the expression of alpha-d-mannose binding sites in human spermatozoa, human sperm-oocyte interaction and the development of early stages of mouse embryo in the presence of levonorgestrel (LNG). Semen samples were obtained from 16 normozoospermic men. Spermatozoa were separated by Percoll gradient and incubated overnight for capacitation. The kinetic analysis of the expression of alpha-D-mannose binding sites was determined at 0, 4 and 22 h and in 22 h-capacitated spermatozoa that had been exposed to 1, 10 or 100 ng/mL of LNG or to a control medium for 30 min. Sperm binding sites for alpha-D-mannose were detected using commercial alpha-D-mannosylated bovine serum albumin conjugated with fluorescein isothiocyanate. To evaluate sperm-oocyte interaction, each oocyte was placed in a 100-microL droplet containing one of the three doses of LNG or control medium and inseminated with 1.0 x 10(5) motile spermatozoa/mL, after which the number of bound spermatozoa was evaluated. A total of 157 two-cell embryos recovered from eight mice was pooled and assigned randomly to treatment (1, 10 or 100 ng/mL of LNG) or control groups. There was a significant increase in the expression of specific alpha-d-mannose binding sites (Patterns II and III) during the incubation of spermatozoa under capacitating conditions. In the presence of LNG, results showed that there was no significant difference in the expression of specific alpha-d-mannose binding sites (Patterns II and III) at any LNG concentration tested compared with those spermatozoa in control medium. None of the LNG concentrations were capable of modifying the number of spermatozoa tightly bound to the human zona pellucida. There was no association between the presence or absence of LNG or the different doses of LNG evaluated and mouse embryo development. In conclusion, the hypothesis that in vitro exposure to LNG could interfere with sperm function and could contribute to the mechanism of action of this form of contraception was not confirmed but cannot be ruled out by the results of this study.  相似文献   
234.
Fruits of Heteropterys glabra (Malpighiaceae) are used in South-American folk medicine as a sedative and anxiolytic agent. In present research, we studied neurophysiological effects of the plant. Ethanolic extract was assayed in DBA/2J mice in order to evaluate the sleep wakefulness cycle, electroencephalogram (EEG) and visual evoked potentials (VEP). The results of our experiments indicated that the EtOH extract of the plant induced a reduction of motor activity and alterations of EEG and VEP parameters, supporting the possibility that the plant acts as an anxiolytic/sedative agent, thus, confirming its usual assumption and the traditional use.  相似文献   
235.
236.
Failure of fertilization in patients undergoing in vitro fertilization (IVF) deserves extensive analysis for better prediction of the success or failure of this therapeutic modality. Consequently, we retrospectively studied the 52 couples in whom fertilization failed during Norfolk series 18 to 25, in an effort to establish the precise causes of failure. In the initial evaluation, pure oocyte abnormalities were identified in 19.2% of the cases; 32.6% showed sperm abnormalities, and a combination of oocyte and sperm anomalies was found in 7.7%. In 40.4% of the cases, failure of fertilization could not be explained. Re-assessment of sperm morphology by new, strict criteria increased the identification of sperm abnormalities to 61.5% and of combined sperm and oocyte anomalies to 13.4%, for a total of 74.9% of sperm factors involved, as opposed to 40.3% in the original evaluation. The incidence of unexplained failed fertilization was substantially reduced, to 11.5%. In a control group (tubal infertility) matched by age, date, and stimulation, in whom fertilization occurred, 83.3% had normal sperm parameters as judged by the new criteria for morphology evaluation. This paper emphasizes the need for a more accurate diagnosis of sperm abnormalities to establish the true incidence of this factor in failed fertilization and to obtain information of prognostic value to patients and clinicians.  相似文献   
237.
OBJECTIVE: The purpose of this study was to understand the transition process from providing Norplant, the six-capsule first contraceptive implant system, to providing Jadelle, the two-rod second-generation system, in a clinical setting with extensive experience providing Norplant implants. MATERIALS AND METHODS: Two hundred forty-nine women requesting contraceptive implants from the PROFAMILIA clinic (Santo Domingo, Dominican Republic) were provided with information regarding the differences and similarities between the two implant systems being studied, including the easier insertion and removal procedures and the possible shorter use life associated with Jadelle. A questionnaire evaluating their preference and the reason why they chose either system was provided. The health care providers' opinions about the two systems were also studied. RESULTS: Fifty-three percent of the women preferred Jadelle over Norplant. The main reason behind their preference for Jadelle was its reduced number of implants with easier insertion and removal and less visibility in the arm, whereas that for Norplant was greater familiarity. Providers overwhelmingly preferred Jadelle. A 1-h presentation was sufficient training for providers experienced with Norplant. None had any problem with the management of Jadelle. CONCLUSION: The inclusion of Jadelle in a clinic with extensive experience with Norplant was easy and uneventful, but both methods should be available during a transition period of several months while confidence in the new method is being acquired by the community.  相似文献   
238.
The use of the combination of a gestagen, medroxy-progesterone acetate, and an androgen, testosterone enantate as a method for male contraception has been tried. The treatment was given at monthly injections, the gestagen at two dose levels. 150 and 300 mg/month and the androgen at 250 mg month. No substantial difference was observed between the two treatment schedules. Azoospermia was achieved in a majority of the patients within 4 months of treatment, but was never observed in all patients. After discontinuation the sperm count increased gradually after 2–3 months. This treatment schedule is not adequate for contraceptive purposes. Sexual impotency was not a problem for any of the subjects although testosterone in serum was reduced to 20–25% of the pretreatment level.  相似文献   
239.
Lippes loops and Copper-Ts were inserted in the first week after abortion to 705 and 639 women, respectively, as part of the routine work of a large Obstetrics Department in Santiago, Chile. The continuation rate after a year was better for the Copper-T (78.5) than for the Lippes loop (72.0), derived from lower expulsion (13.0 vs. 16.5) and medical removal rates (2.9 vs. 7.2). Pregnancy rate was higher for the Copper-T (3.5) than for the Lippes loop (2.6).  相似文献   
240.
Fifteen women with normal basal gonadotropin levels and adequate responses to conventional gonadotropin stimulation for in vitro fertilization (IVF) were pretreated with leuprolide acetate (LA) beginning in the midluteal phase prior to a repeat IVF attempt. A significantly longer duration of stimulation requiring a significantly higher total dosage of gonadotropins was observed in LA cycles. The number of preovulatory oocytes retrieved and preembryos transferred was significantly higher in LA cycles. Six of 15 women (40%) had cryopreservation of supernumerary preembryos in LA cycles, versus none in non-LA cycles; 22% of preovulatory oocytes aspirated in LA cycles were available for cryopreservation for future transfer. Five pregnancies occurred in the 15 LA cycles. IVF patients with normal basal gonadotropin levels and normal responses to conventional gonadotropin stimulation benefit from LA pretreatment.  相似文献   
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