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141.
Sexually experienced Wistar male rats were used to investigate (a) urine voiding in the presence of nearby estrous females and the control of such voiding by (b) steroid hormones and (c) peripheral nerves supplying the genitourinary system. The first experiment showed that males always have a low rate of urine voiding that is significantly increased when a receptive female is around. Thus, it is suggested that an airborne scent from the female stimulates the olfactory system of males, triggering urine emission to transmit sex-related messages, i.e., male rats display the well-known urine-marking behavior of mammals. The number of urine marks and sniffing to females decreased after castration, and were restored after exogenous treatment with testosterone or estradiol. The proposed hypothesis is that airborne scents from the female activate the aromatization process in nuclei of the olfactory pathway of the male, evoking a cascade of neuronal responses that finish in urine marking. Peripheral nerves supplying the genitourinary system are the viscerocutaneous branch of the pelvic nerve (Vc) and the hypogastric (Hg). Data showed that both nerves are important for the central control of urine storage and voiding. Transection of Vc almost blocked urine marking, while Hg lesion increased the number of marks. Thus, it is discussed that Vc is the most important nerve in charge of voiding the bladder, and that Hg is important for continence.  相似文献   
142.
We developed a set of nine polymorphic microsatellite markers from a genomic library enriched for dinucleotide repeats in the European polecat Mustela putorius. Microsatellite loci amplification was tested on fresh tissues and museum samples collected over the last 40?years in central and northern Italy. Number of alleles per locus ranged from 3 to 7. Mean observed and expected heterozygosity were 0.48 and 0.61, respectively. This novel set of species-specific microsatellite loci will be particularly useful to assess fine patterns of genetic structure and degree of isolation of European polecat populations.  相似文献   
143.
Rats can display a conditioned partner preference for individuals that bear an odor previously associated with sexual reward. Herein we tested the possibility that odors associated with the reward induced by social play in prepubescent rats would induce a conditioned partner preference in adulthood. Two groups of 31-day-old, single-housed female rats were formed, and were given daily 30-min periods of social play with scented females. In one group, almond scent was paired with juvenile play during conditioning trials, whereas lemon scent functioned as a novel odor in the final test. The counterbalanced group received the opposite association. At age 42, females were tested for play partner preference with two males, one almond-scented and one lemon-scented. In both groups females displayed a play partner preference only for males scented with the paired odor. They were ovariectomized, hormone-primed, and at age 55 were tested for sexual partner preference with two scented stud males. Females displayed a sexual preference towards males scented with the paired odor as observed with more visits, solicitations, hops and darts, intromissions and ejaculations. These results indicate that olfactory stimuli paired with juvenile play affects later partner choice for play as well as for sex in female rats.  相似文献   
144.
Accumulated metals in soils negatively affect dwelling organisms. Earthworms, which are widespread and perform various essential functions, are able to accumulate metals that can damage the coelomic cells. The aim of this work was to evaluate the effect on Eisenia fetida lysosomal membrane stability both during and after copper exposure, and finally to link this to internal concentrations. E. fetida specimens were exposed to a reference soil and two Cu-spiked soils (35 and 350 mg kg−1 d.w.) for 14 days (uptake period) and then transferred into the reference soil for other 18 days (elimination period). After 3 days of uptake, internal Cu concentrations increased and were higher in the specimens exposed to soils spiked with 350 mg Cu kg−1 d.w. After 2 days of elimination, a strong decrease of internal Cu concentrations was always observed. The lysosomal membrane stability, measured as neutral red retention-times, was approximately 50 min for the earthworms exposed to the reference soils, whereas it decreased, at the end of the uptake period, to 21 and 13 min, respectively, for the organisms exposed to soils spiked with 35 and 350 mg Cu kg−1 d.w. A full recovery of the lysosomal membrane stability was reached after 14 and 18 days of the elimination period, respectively, for the organisms exposed to soils spiked with 35 and 350 mg Cu kg−1 d.w. The neutral-red assay would seem a good biomarker since the lysosomal membrane stability of E. fetida appeared to respond rapidly and strongly to soil copper contamination.  相似文献   
145.

Purpose of Review

The aim of this review is to provide current evidence on the biological and psychological mechanisms that underlie sexual partner preferences (SPP) in humans and animals.

Recent Findings

SPP depend mainly on prenatal (adaptive) organization of the brain, but can be drastically modified via learning under enhanced dopaminergic (DA) and oxytocinergic (OT) activity.

Summary

SPP can be categorized as in those directed towards partners who display indicators of biological fitness (IBF) or towards partners who do not show those indicators. The IBF function as unconditioned stimuli that presumably activate prenatally organized brain areas that mediate the salience of those stimuli. However, we discuss some evidence indicating that SPP not directed towards IBF (i.e., paraphilias) might be consequence of a learning process that occurs under enhanced DA or OT activity, resulting in new powerful learning with additional brain areas involved.
  相似文献   
146.

Introduction

Status epilepticus (SE) is an epileptic condition that can cause cerebellar atrophy and loss of Purkinje cells in both humans and research animals. Cerebellum is a region rich in γ-aminobutyric acid (GABA) and glutamate, and some studies have shown that their concentrations may be altered after convulsions. However, there are no studies showing the effect of seizures on different cerebellar regions in developing rats. Time course of the effect of status epilepticus induced in the developing rat on γ-amino butyric acid and glutamate cerebellar concentration.

Methods

SE was induced using the lithium-pilocarpine model; control rats were injected with saline solution. At 6 h, 24 h, and 1 month after SE o saline injection, rats were anaesthetised with pentobarbital and decapitated, and cerebella were extracted. The vermis and hemispheres were dissected and homogenised in 0.1 M perchloric acid containing 4 mM sodium bisulfite. Homogenates were centrifuged and supernatant was used to quantify GABA, and glutamate tissue concentrations by HPLC coupled with fluorometric detection.

Results

SE did not alter GABA and glutamate tissue concentration in the cerebellar vermis and hemispheres.

Conclusion

The developing rat cerebellum is resistant to both short- and long-term neurochemical changes induced by SE.  相似文献   
147.
Opportunities for participation in clinical trials are a core component of the care of children with cancer. In Ontario, many pediatric patients live long distances from their cancer center. This paper describes the work that was done in order to allow patients participating in Children's Oncology Group trials to receive care, including research protocol related care, jointly between the tertiary pediatric cancer center and the closer‐to‐home satellite center. The system is a pragmatic risk‐based model, supporting excellence in care while ensuring good conduct of the research in compliance with applicable regulations and guidelines, including ethics oversight.  相似文献   
148.
This multicenter study tested the actuation of a new model of pharmacovigilance, focused on three pharmacological wide-used categories (non-steroidal anti-inflammatory drugs, NSAID, oral anticoagulants, and antihypertensive drugs). Besides the traditional way of pharmacovigilance, an active investigation was performed, using a phone-structured interview. Patients discharged from the participating hospitals were included into the study, if their prescribed therapy included some of the above drugs and after informed consent. Three hundred subjects were interviewed, 100 for each pharmacological category. For a period of six months after patient's discharge from the hospital, a traditional pharmacovigilance survey was carried out. About 30 days after discharge from the hospital, patients were interviewed by the medical staff and data recorded. NSAID group stratification evidenced a significant percentage of severe haemorrhage among the patients who were using acetylsalicylic acid (ASA) as antiaggregant (6.8%) compared to the patients who were using non-ASA NSAID, at therapeutic dosage (1.8%). From this data, it seems that the active pharmacovigilance model was able to better highlight a real problem for the NSAID category, in particular it evidenced a pharmacological subclass (ASA) more prone to cause ADR than expected from literature data related to whole pharmacological class. Given the required economical effort, this pharmacovigilance method could take place as a selected tool when pharmacovigilance signals from the international databases become consistent or for new wide-used drugs, to screen potentially dangerous pharmacological subclasses, normally “hidden” because of a “camouflage” among ADRs of the entire pharmacological class.  相似文献   
149.
OBJECTIVE: No consistent predictors of outcome have been identified for the pharmaco-therapy of obsessive-compulsive disorder (OCD). Recent factor analytic studies have identified meaningful symptom dimensions that may be related to response to serotonin reuptake inhibitors and other treatments. METHOD: A total of 354 outpatients with primary OCD were administered the Yale-Brown Obsessive Compulsive Scale Symptom Checklist, and its 13 main symptom categories were factor analyzed by using principal components analysis. The identified symptom dimensions were then entered into multiple regression models as outcome predictors of response to serotonin reuptake inhibitors and placebo response in a group of 150 nondepressed subjects who completed six double-blind, placebo-controlled trials with a serotonin reuptake inhibitor (clomipramine, fluvoxamine, fluoxetine, sertraline, and paroxetine). Eighty-four patients received a serotonin reuptake inhibitor and 66, placebo. RESULTS: The principal components analysis identified five factors that explained 65.5% of variance in outcome: symmetry/ordering, hoarding, contamination/cleaning, aggressive/checking, and sexual/religious obsessions. Serotonin reuptake inhibitors were significantly superior to placebo on all outcome measures. Initial severity of OCD was related to greater posttreatment severity of OCD. Higher scores on the hoarding dimension predicted poorer outcome following treatment with serotonin reuptake inhibitors, after control for baseline severity. No predictors of placebo response were identified. Exclusion of clomipramine did not modify the overall results, suggesting a cross-serotonin reuptake inhibitor effect. CONCLUSIONS: The identified symptom dimensions are largely congruent with those identified in earlier reports. Patients with OCD vary in their response to treatment with serotonin reuptake inhibitors. The presence of hoarding obsessions and compulsions is associated with poorer response to serotonin reuptake inhibitors.  相似文献   
150.

Objective

The mechanisms by which monocyte/macrophage cells migrate to the joint involve a series of integrated adhesion and signaling events in which chemokines and their receptors are strongly implicated. This study was undertaken to investigate the hypothesis that stromal cell–derived factor 1 (SDF‐1), a CXC chemokine (CXCL12), plays a critical role in monocyte/macrophage localization to synovium.

Methods

SDF‐1 and CXC receptor 4 (CXCR4) expression in rheumatoid arthritis (RA) and osteoarthritis synovium and graft SDF‐1, tumor necrosis factor α (TNFα), and human and murine vascular markers were examined by immunohistochemistry and doubleimmunofluorescence. The functional capacity of SDF‐1 to modulate monocyte migration into joints was investigated by examining the localization of pro‐myelomonocytic U937 cells into synovial tissue transplanted into SCID mice. SDF‐1, TNFα, or saline was injected into graft sites and response determined by the number of fluorescently labeled U937 cells (injected intravenously) detected in grafts by ultraviolet microscopy.

Results

SDF‐1 and CXCR4 were highly expressed in CD68+ cells in the RA synovium. SDF‐1 induced U937 cell migration in vitro and in vivo in a dose‐dependent manner and, in vivo, SDF‐1 was more effective than TNFα. In contrast to TNFα, SDF‐1 did not induce intracellular adhesion molecule 1 in transplant microvasculature. Furthermore, intragraft injection of SDF‐1 did not up‐regulate TNFα, or vice versa.

Conclusion

This study demonstrates, for the first time, that SDF‐1 is functional in vivo when injected into synovial grafts. In addition, SDF‐1 is more potent than TNFα, and its mechanisms of action appear to be autonomous. Therefore, SDF‐1 may be an important TNF‐independent molecule involved in the migration to and retention of inflammatory effector cells in the joint.
  相似文献   
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