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111.
To assess the effectiveness of maternal self-administration of nevirapine for prevention of mother-to-child transmission (MTCT) of HIV, we conducted a program to provide maternal and newborn doses of nevirapine to pregnant women in rural Uganda. Women provided blood for HIV testing and were offered voluntary counseling and testing (VCT) during annual community HIV surveys. HIV-positive women who accepted VCT were offered nevirapine tablets and syrup. Blood samples were collected postpartum from women and their babies. Infants were tested for HIV by polymerase chain reaction (PCR), and a subsample of maternal and infant blood was assayed for nevirapine. Among the 981 women tested for HIV, 900 (91.7%) accepted VCT, of whom 105 (11.7%) were HIV-positive. Ninety-three women accepted nevirapine, of whom 81 (87.1%) were followed postpartum; 75 (92.6%) reported receipt of the drug, and 69 reported taking the tablets (85.2%). There were 81 liveborn babies (3 sets of twins), and 67 (84.8%) received the syrup. In a subsample of 25 mothers reporting receipt of the drug, nevirapine was detected in 22 (88.0%) and 24 (96.0%) babies tested. PCR of 67 infant blood samples identified 5 HIV-positive (MTCT rate = 7.5%, 95% confidence interval [CI]: 0.3%-16.6%). Mothers can administer nevirapine to themselves and their newborns and can achieve low rates of perinatal HIV infection.  相似文献   
112.
Dendritic cells (DC) are a group of potent antigen-presenting cells (APC) specialized for initiating T cell immune responses. They originate from the bone marrow and upon stimulation with bacterial products, cytokines or CD40 ligation they acquire the ability to migrate to the secondary lymphoid organs. In vitro DC can be generated from human CD34(+) bone marrow cells and CD14(+) peripheral blood monocytes after culture with different cytokine combinations. Since most leukemic cells and tumors in general are devoid of APC capacities, various strategies have been used to increase their recognition and confer the capacity of antigen presentation on them. Because of our interest in the design of vaccine immunotherapy protocols for the adjuvant treatment of patients with lymphoid malignancies (LM), we chose to explore the capacity of human acute lymphoblastic leukemia, chronic lymphocytic leukemia and plasma cell leukemia to differentiate into cells with APC and DC features. Our results among a sample of 10 patients demonstrate that such approach is feasible. Leukemic cells could be induced in the presence of IL-4 and CD40L to exhibit a DC morphology with a phenotype of mature DC-like cells. They could also induce a potent proliferative response in naive CD4(+) T cells. In addition, they expressed chemokine receptor CCR7 and CD62L, and could drive T cells towards a T(h)1 response with secretion of IFN-gamma. Our strategy leading to increased LM cell immunogenicity may have potential clinical applications and LM appear to be attracting candidates for adjuvant vaccination and adoptive immunotherapy.  相似文献   
113.
Adrenoleukodystrophy (ALD) is an X-linked disorder caused by a defect in the metabolism of long chain fatty acids leading to demyelination, neurodegeneration, and death. The disease typically presents in young boys and adolescent boys. Allogeneic bone marrow transplantation has been used to halt progression of the disease. However, many patients lack suitable HLA- matched related donors and must rely on unmatched donors for a source of stem cells. The purpose of this study was to evaluate outcomes of unrelated donor umbilical cord blood transplantation after chemotherapy-based myeloablative conditioning and retrospectively determine if baseline studies correlate and help predict outcome. Between November 22, 1996, and November 3, 2005, 12 boys with X-linked ALD who lacked HL- matched related donors were referred to Duke University Medical Center for transplantation. These children were conditioned with myeloablative therapy including busulfan, cyclophosphamide, and antithymocyte globulin before receiving umbilical cord-blood transplants from unrelated donors. Baseline studies of neurophysiologic, neuroimaging, and neurodevelopmental status were performed and patients were subsequently evaluated for survival, engraftment, graft-versus-host disease, and neurodevelopmental outcomes. A substudy evaluated whether baseline neuroimaging and neurophysiologic studies correlated with cognitive and motor function and if these studies were predictive of posttransplantation outcomes. The umbilical cord blood grafts had normal levels of very long chain fatty acids. They delivered a median of 6.98 x 10(7) nucleated cells per kilogram of recipient body weight and were discordant for up to 4 of 6 HLA markers. Neutrophil engraftment occurred at a median of 22.9 days after transplantation. Three patients had grade II-IV acute graft-versus-host disease; 2 had extensive chronic graft-versus-host disease. Cumulative incidence of overall survival of the group at 6 months is 66.7% (95% confidence interval 39.9-93.3%). Median follow-up was 3.3 years (range 12 days to 6.3 years). As previously reported with bone marrow transplantation, symptomatic patients faired poorly with lower survival and rapid deterioration of neurologic function. This study included 3 patients transplanted at a very young age (2.6-3.5 years) before the onset of clinical symptoms who continue to develop at a normal rate for 3-5 years posttransplant. Although baseline Loes scores correlated with cognitive and motor outcome, neurophysiologic studies failed to show statistically significant differences. Transplantation of boys with X-linked ALD using partial HLA-matched umbilical cord blood yields similar results to those previously reported after bone marrow transplantation. Superior outcomes were seen in neurologically asymptomatic boys less than 3.5 years of age at the time of transplantation. Baseline Loes scores were a strong predictor of cognitive and motor outcome.  相似文献   
114.
De novo UMP synthesis is a critical metabolic pathway for nucleic acid synthesis and for a variety of metabolic pathways. The pathway is a target for many widely used cancer chemotherapy agents, several of which are pyrimidine analogs. Humans and cattle have been described with mutations in UMP synthesis that lead to serious inborn errors of metabolism. Dihydroorotate dehydrogenase (EC 1.3.3.1) (DHODH) carries out the fourth committed step in the pathway and may also be important for mitochondrial electron transport and oxygen radical metabolism. We report here that the gene encoding this enzyme in humans is located in the chromosomal region 16q22. With the mapping of DHODH, the mapping of all the steps of UMP synthesis is complete. All three genes involved map to different human chromosomes. This information is important in consideration of regulation of UMP synthesis in mammals, including humans.  相似文献   
115.
Using in vivo assays for alloreactivity, the responsiveness of maternal lymph node cells was shown to be increased when cells were harvested from both syngeneically and allogeneically pregnant mice. In addition, foetal liver and thymus cells induced a state of delayed type hypersensitivity to alloantigens whereas trophoblastic tissue, in the form of 12 to 15 day metrial glands, did not.

The influence of mouse placenta on in vitro immune responses was tested using 7-day ectoplacental cones as sources of trophoblastic tissue. Ectoplacental cones increased a T cell dependent but not a T cell independent antibody response, whereas T cell dependent cytotoxicity was reduced. The findings reported in this paper suggest that murine ectoplacental cones are a particularly useful tissue with which to study both specific and non-specific immunological activities of the trophoblast in syngeneic and allogeneic pregnancies.

  相似文献   
116.
Acute inhibition of NO synthesis decreases left ventricular (LV) work and external efficiency, but it is unknown whether compensatory mechanisms can limit the alterations in LV mechanoenergetics after prolonged NO deficiency. Eight chronically instrumented male mongrel dogs received 35 mg kg−1 day−1 of N ω-nitro-L-arginine methyl ester orally for 10 days to inhibit NO synthesis. At spontaneous beating frequency, heart rate, coronary blood flow, peak LV pressure, end-diastolic LV pressure and the maximum derivative of LV pressure (d P /d t max) were not significantly different vs. baseline, whereas LV end-diastolic diameter (32.5 ± 1.0 vs. 37.6 ± 1.4 mm) and LV stroke work (515 ± 38 vs. 650 ± 44 mmHg mm), were reduced (all P < 0.05). The slope of the LV end-systolic pressure-diameter relationship was increased at 10 days vs. baseline (13.9 ± 1.0 vs. 9.6 ± 0.9 mmHg mm−1, P < 0.05), while the end-diastolic LV diameter was smaller at matched LV end-diastolic pressures. At fixed heart rate (130 beats min−1), cardiac oxygen consumption was increased (12.2 ± 1.5 vs. 9.9 ± 1.0 ml min−1), and the ratio between stroke work and oxygen consumption was decreased by 33 ±7 % (all P < 0.05) after NO inhibition. We conclude that sustained inhibition of NO synthesis in dogs causes a decrease in LV work despite an increased contractility, which is most probably due to reduced diastolic compliance and a decrease in external efficiency. Thus, prolonged NO deficiency is not compensated for on the level of LV mechanoenergetics in vivo .  相似文献   
117.
The insertion/deletion (I/D) polymorphism of the human angiotensin-converting enzyme (ACE) gene is a major determinant of circulating ACE levels. The D allele has been suggested to be a potent risk factor for coronary artery disease; however, the effect of the ACE gene on carotid atherosclerosis remains controversial. We therefore studied the relationship between the ACE gene I/D polymorphism and carotid artery intima-media thickness (IMT). A random sample of 300 men aged 50-59 years living in southern Finland were selected, and 233 agreed to participate (74%). Data were collected in 219 subjects. Quantitative B-mode ultrasonography was used to measure the maximum near and far wall IMT of right and left common, bifurcation, and internal carotid artery. The mean maximum IMT (overall mean) was calculated as the mean of 12 maximum IMTs at 12 standard sites. Patients with an IMT higher than 1.7 mm in at least one of 12 standard sites were assumed to have carotid atherosclerosis. The I/D polymorphism was determined by polymerase chain reaction. Overestimation of the frequency of the DD genotype was eliminated by insertion-specific primer and the inclusion of 5% dimethylsulfoxide. No significant differences were found in carotid wall thickness between the three genotypes; the overall mean IMT were 1.18 +/- 0.30, 1.22 +/- 0.24, and 1.08 +/- 0.40 mm in genotypes of II, ID, and DD, respectively. Similarly, the ACE genotypes and allele frequencies did not differ significantly between the subjects with and those without carotid atherosclerosis. There was no association in the subgroups among only nonsmoking subjects or subjects without chronic medication. The present data indicate that the I/D polymorphism of the ACE gene is not related to carotid IMT and is unlikely to play a major role in carotid atherosclerosis.  相似文献   
118.
BACKGROUND: Subjective quality of life has gained a crucial role as a global measure of outcome in mental health care. This study aimed to investigate the impact of meeting needs for care, as assessed by both patients and mental health professionals, to improve the subjective quality of life in a sample of patients receiving community-based psychiatric care. METHOD: The study was conducted using a 4-year prospective longitudinal design. A cohort of patients from the South-Verona Community-based Mental Health Service (CMHS) was assessed at baseline and follow-up using, among other social and clinical measures, the Camberwell Assessment of Need (both staff and patient versions) and the Lancashire Quality of Life Profile. Predictors of changes of subjective quality of life were explored using block-stratified multiple regression procedures. RESULTS: Improvement in patients' clinical conditions as well as the reduction in patient-rated unmet needs in the social domain predicted an increase in subjective quality of life over 4 years; changes in staff-rated needs did not show any association with changes in subjective quality of life. CONCLUSIONS: Meeting self-perceived social needs, beyond symptoms reduction, seems to be of particular importance for ensuring a better quality of life for people with mental disorders. If the main goal of mental health care is to improve the quality of life of users, a policy of actively addressing patient-rated needs should be implemented.  相似文献   
119.
We have previously shown that unlike endogenous ? genes, unrearranged ? transgenes undergo V?-J? recombination in T as well as B cells of transgenic mice. To determine whether the difference in recombination specificity of the transgenic and endogenous ? genes is associated with differences in DNA structure, the methylation status of the endogenous genes and three unrearranged ? transgenes was compared. The J?-C? locus of the transgenes was found to be hypomethylated in all tissues of the transgenic mice. In contrast, methylation of the endogenous ? genes was tissue and developmentally regulated. Hypomethylation of the endogenous J?-C? region occurs only in cells of the B lineage undergoing, or having completed ? gene recombination. Transfection of fibroblasts from transgenic and control mice with the recombination activating genes, Rag1 and Rag2, led to a high level of rearrangement of the hypomethylated transgenic, but not the endogenous ? genes. These results suggest that hypomethylation defines an accessible state of the ? locus and that methylation/demethylation could be involved in the control of ? gene rearrangement during lymphocyte differentiation.  相似文献   
120.
Peripheral nerve inputs have an inhibitory effect on motor cortex excitability at short intervals (short-latency afferent inhibition, SAI). This can be tested by coupling electrical stimulation of peripheral nerve with transcranial magnetic stimulation (TMS) of the motor cortex. SAI is reduced by the anticholinergic drug scopolamine, and in patients with Alzheimer's disease. Therefore, it is possible that SAI is a marker of central cholinergic activity important for memory function. The benzodiazepine lorazepam also reduces SAI. Since benzodiazepines impair memory formation, but do not do so uniformly, with a maximum amnesic effect after lorazepam but less or no effect after diazepam, we were interested in testing in this non-behavioural study to what extent the effects of lorazepam and diazepam on circuits involved in SAI could be dissociated. In addition, and for control, we tested the effects of lorazepam and diazepam on short-interval intracortical inhibition (SICI), a motor cortical inhibition mediated through the GABAA receptor. Lorazepam markedly reduced SAI, whereas diazepam slightly increased it. In contrast, both benzodiazepines uniformly increased SICI. Our findings demonstrate opposite effects of lorazepam and diazepam on SAI, an inhibition modulated by central cholinergic activity, but the same effects on SICI, a marker of neurotransmission through the GABAA receptor. This dissociation suggests, for the first time, that TMS measures of cortical inhibition provide the opportunity to segregate differences of benzodiazepine action in human central nervous system circuits.  相似文献   
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