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1.
The bed nucleus of the stria terminalis (BNST) and its adrenergic input are key components in stress-induced reinstatement and maintenance of drug use. Intra-BNST injections of either beta-adrenergic receptor (beta-AR) antagonists or alpha2-adrenergic receptor (alpha2-AR) agonists can inhibit footshock-induced reinstatement and maintenance of cocaine- and morphine-seeking. Using electrophysiological recording methods in an in vitro slice preparation from C57/Bl6j adult male mouse BNST, we have examined the effects of adrenergic receptor activation on excitatory synaptic transmission in the lateral dorsal supracommissural BNST (dBNST) and subcommissural BNST (vBNST). Alpha2-AR activation via UK-14,304 (10 microM) results in a decrease in excitatory transmission in both dBNST and vBNST, an effect predominantly dependent upon the alpha2A-AR subtype. Beta-AR activation via isoproterenol (1 microM) results in an increase in excitatory transmission in dBNST, but not in vBNST. Consistent with the work with receptor subtype specific agonists, application of the endogenous ligand norepinephrine (NE, 100 microM) elicits two distinct effects on glutamatergic transmission. In dBNST, NE elicits an increase in transmission (62% of dBNST NE experiments) or a decrease in transmission (38% of dBNST NE experiments). In vBNST, NE elicits a decrease in transmission in 100% of the experiments. In dBNST, the NE-induced increase in synaptic transmission is blocked by beta1/beta2- and beta2-, but not beta1-specific antagonists. In addition, this increase is also reduced by the alpha2-AR antagonist yohimbine and is absent in the alpha2A-AR knockout mouse. In vBNST, the NE-induced decrease in synaptic transmission is markedly reduced in the alpha2A-AR knockout mouse. Further experiments demonstrate that the actions of NE on glutamatergic transmission can be correlated with beta-AR function.  相似文献   
2.
How thick is the glycocalyx of human erythrocytes?]   总被引:1,自引:0,他引:1  
The aim of the experiment was to determine the thickness of the glycocalyx of human erythrocytes of the blood group A. For that purpose, the distance between the electron dense contrasted lipid layer of the plasmalemma and gold sol particles loaded with Helix pomatia lectin was determined. The mean thickness of the glycocalyx under this conditions was 5.9 nm.  相似文献   
3.
This study uses data from the Epidemiologic Catchment Area (ECA) surveys to examine the strength of the association between psychotic symptoms and violent behaviour, controlling for underlying mental disorder, substance abuse, sociodemographic characteristics and use of mental health services, in a representative sample of community residents. A replication is conducted of a study that found an increased risk of violence associated with a particular cluster of psychotic symptoms involving perceived threat and internal control-override (TCO). Respondents who reported TCO symptoms were about twice as likely to engage in assaultive behaviour as those with hallucinations or other psychotic symptoms, and about five times as likely as those with no mental disorder. The combination of substance use disorders with TCO symptoms added significantly to the risk of violent behaviour. Those with a history of using mental health services also posed a higher risk of violence, probably due to the differential selection of more severely ill and ‘dangerous’ individuals into treatment settings. Copyright © 1996 Whurr Publishers Ltd.  相似文献   
4.
The authors tried to clarify relations between autoimmune gastritis and isolated atrophic corpus gastritis by bioptic corporal and antral examinations from 150 probands as well as examinations of gastrin in serum and parietal cell antibody tests. Only 30% of all patients examined with isolated atrophic gastritis of the corpus part revealed criteria of an autoimmune gastritis. Therefore investigations of antibodies against parietal cells are necessary to mark off both clinical pictures. This differentiation seems to be necessary regarding the high risk of gastric cancer following an autoimmune gastritis.  相似文献   
5.
The localization of thyrotropin-releasing hormone immunoreactivity (TRH-IR) has been determined in the thoracic spinal cord of male and female guinea pigs. The immunoreactive product is localized in nerve fibre varicosites and terminals throughout the spinal gray matter and in some regions of the white matter. There are not TRH-IR neurons in the spinal cord. The highest density of IR structures is observed in the intermediate zone, in the central gray and in the ventral horns, around the motoneurons. Less TRH-IR structures are observed in the superficial layers and substantia gelatinosa of the dorsal horns. Between the ependymal cells of the central canal are observed single TRH-IR fibres and terminals too. Most of the TRH-IR fibres and terminals in the intermediate zone and in the central gray are constituents of the vegetative network (Galabov and Davidoff, 1976 and Davidoff et al. 1985). As to the origin of the spinal cord TRH-IR fibres and terminals two main possibilities exist: a) From primary afferent neurons situated in the dorsal root ganglia, which is quite uncertain; b) From supraspinal neurons which send their axons descending in the white matter and in the fasciculi longitudinales laterales and mediales (Johansson et al. 1981, 1983). The wide diversity of neuroactive substances in the thoracic spinal cord vegetative network and the origin of its fibres and terminals suggests that this network may play an important role in the integration of the central and peripheral vegetative nervous system, as well as probably in the integration of the somatic and the vegetative nervous system.  相似文献   
6.
Sexual differentiation of dopaminergic neurons was studied in gender-specific cultures. Dissociated cell cultures were prepared from di- or mesencephalon of gestational day 14 rat embryos and raised in the absence or presence of 17 beta-estradiol or testosterone for up to 13 days in vitro (DIV). Developmental profiles of levels of dopamine (DA) and metabolites as well as capacity for vesicular storage of the transmitter were determined by HPLC. Tyrosine hydroxylase-immunoreactive (TH-IR) neurons were counted. Higher levels of DA were measured in female than in male cultures of both brain regions. In mesencephalic cultures, the differences in DA levels were fully accounted for by sex differences in numbers of TH-IR cells, whereas no sex differences in cell numbers were found in diencephalic cultures. Dihydroxyphenylacetic acid (DOPAC) levels and vesicular storage capacity matured faster in mesencephalic than in diencephalic cultures, but no sex differences were observed. Homovanillic acid (HVA) could not be detected except in 13-DIV mesencephalic cultures. Hormonal treatment did not erase sexual differentiation of dopaminergic neurons. Irrespective of the gender, however, both steroids decreased DA and DOPAC contents in diencephalic cultures but not in mesencephalic cultures. It is proposed that sexual differentiation of dopaminergic systems proceeds in a region-specific fashion and that neurogenesis and development of various parameters of dopaminergic activity may be differentially affected. Sexual differentiation of dopaminergic neurons may be initiated independently of the action of gonadal steroid hormones and may subsequently be modified by differences in hormonal environment.  相似文献   
7.
8.
The management of self-destructive behavior in eating disorder patients with borderline personality is a genuine therapeutic challenge. We present an integrated psychotherapy appproach that we utilize in the context of an extended therapeutic milieu. This treatment model enables coordinated intervention to occur in three different arenas: individual psychotherapy, group psychotherapy, and consultation intervention. The paper closes with a discussion of the limitations of this approach.  相似文献   
9.
10.
BACKGROUND: Immunosuppression therapy with bolus glucocorticoids causes regional osteoporosis in the axial skeleton of heart transplant recipients (HTR). No preventive strategy is generally accepted for steroid-induced bone loss. METHODS: To determine the efficacy of an anti-osteoporosis regimen that combined a bisphosphonate agent (alendronate sodium) with the osteogenic stimulus of mechanical loading, 25 HTRs were randomly assigned either to a group that received alendronate (10 mg/day) for 6 months (ALEN; n = 8), a group that received alendronate (10 mg/day) and performed specific resistance exercises for 6 months (ALEN + TRN; n = 8) or to a non-intervention control group (CONTR; n = 9). Alendronate was initiated at 2 months after transplantation. Bone mineral density (BMD) of the total body, femur neck and lumbar spine (L-2 and L-3) was measured by dual-energy X-ray absorptiometry before and 2, 5 and 8 months after transplantation. Resistance training consisted of lumbar extension exercise (MedX) performed 1 day/week and 8 variable resistance exercises (MedX) performed 2 days/week. RESULTS: Pre-transplantation BMD values did not differ among the 3 groups. BMD of the total body, femur neck and lumbar vertebra were significantly decreased below baseline at 2 months after transplantation in CONTR (-2.6 +/- 0.9%, -5.1 +/- 1.8%, -12.5 +/- 4.2%, respectively), ALEN (-2.8 +/- 0.8%, -5.3 +/- 1.6%, -12.0 +/- 3.9%) and ALEN + TRN groups (-2.7 +/- 1.0%, -5.6 +/- 2.1%, -11.2 +/- 3.7%). CONTR had further significant losses of BMD after 3 and 6 months. ALEN had no further regional BMD losses after initiation of alendronate therapy. ALEN + TRN restored BMD of the whole body, femur neck and lumbar vertebra to within 0.9%, 2.1%, and 3.4% of pre-transplantation levels, respectively. CONCLUSIONS: Resistance exercise plus alendronate was more efficacious than alendronate alone in restoring BMD in HTRs. Our results indicate that anti-osteoporosis therapy in this population should include both an anti-resorptive agent as well as an osteogenic stimulus, such as mechanical loading.  相似文献   
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