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71.
This study presents data on the organ distribution of cadmium, and Cd-protein complexes in the body of a man fatally poisoned with CdJ2, after an oral dose of about 5 g.The levels of cadmium in different tissues were (in g per g fr. wt.): liver and kidney cortex about 80, kidney medulla, heart and testes 8.9–10.0, bile 1.9, brain 0.5 and blood 1.1.Almost all cadmium detected in the organism was bound to a low molecular weight protein, tentatively identified as metallothionein.Total amount of 18 mg cadmium was excreted in urine within 6 days of hospitalization, most likely due to Ca-EDTA treatment.The data are suggestive that cadmium induced biosynthesis of metallothionein in the subject.This paper was presented at the 2nd Symposium of Toxicology and Seminar of Pharmacology, Dvoák, September 18–19, 1970.  相似文献   
72.
1. Experiments were performed on anaesthetized, open-chest dogs to determine the reflex effects on systemic blood pressure and heart rate produced by stimulation of the parietal pericardium with bradykinin, prostacyclin, prostaglandin E2 (PGE2), prostaglandin D2 (PGD2) and arachidonic acid. 2. Pericardial application of bradykinin (1 μg) consistently elicited reflex increases in blood pressure and heart rate, whereas application of prostanoids or arachidonic acid in doses up to 10 μg failed to produce any cardiovascular responses. 3. Indomethacin, applied either directly to the parietal pericardium (1 μg/ml) or given intravenously (5 mg/kg) caused a long lasting reduction of the reflex responses to bradykinin. The reflex effects of bradykinin could be temporarily restored by treatment of the pericardium with either prostacyclin (0.1 μg/min) or PGE2 (0.1 μg/min). PGD2 (0.1-1 μg/min) did not influence the bradykinin induced pericardial reflex. 4. Superfusion of arachidonic acid (3 μg/min) over the pericardium amplified the reflex effects of bradykinin when given before, but not when given after indomethacin treatment. 5. The results indicate that locally formed prostanoids, specifically prostacyclin and PGE2, can facilitate activation of the pericardial pressor reflex by bradykinin. The findings may be relevant to the changes in cardiovascular activity occurring during pericardial inflammation.  相似文献   
73.
BACKGROUND AND PURPOSE: The purpose of this study was to demonstrate scintigraphic evaluation of cerebral perfusion in patients with intracranial hemangiomas. MATERIAL AND METHOD: The examination was carried out in 12 patients aged from 12 to 67 years. In all the patients cerebral angiomas were previously diagnosed and all of them were qualified for intravascular embolization. Brain scintigraphy was performed after IV injection of 99mTcECD and included the dynamic phase with images obtained every 2 seconds for 1.5 minutes and SPECT imaging. The semiquantitative analysis of regional cerebral blood flow was based on the comparison between activity in two symmetrical regions of interest. Cerebral angiography combined with intravascular embolization followed the scintigraphic examination. RESULTS: Based on angiograms, the size of the nidus was estimated at 1.0 to 9.0 cm. In 8 patients the dynamic study showed an increased tracer accumulation in the region of angioma. On SPECT images the nidus was visualized as focally decreased perfusion in all cases. A decreased tracer accumulation in the area adjacent to the nidus was detected in 8 patients. The ratio of activity in the region of angioma to activity in normally perfused tissue calculated using the semiquantitative analysis was 52% to 89%. CONCLUSIONS: SPECT images and dynamic phase of cerebral perfusion scintigraphy allow perfusion changes caused by the presence of intracranial angiomas to be identified.  相似文献   
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Adverse drug reactions (ADRs) and iatrogenic diseases have been identified as significant factors responsible for patient morbidity and mortality. Significant studies on drug metabolism in humans have been published during the last few years, offering a deeper comprehension of the mechanisms underlying adverse drug reactions and interactions. More understanding of these mechanisms, and of recent advances in laboratory technology, can help to evaluate potential drug interactions when drugs are prescribed concurrently. Increasing knowledge of interindividual variation in drug breakdown capacity and recent findings concerning the influence of environment, diet, nutrients, and herbal products can be used to reduce ADRs and iatrogenic diseases. Reviewed data suggest that drug treatment should be increasingly custom tailored to suit the individual patient and that appropriately co-prescribed diet and herbal remedies, could increase drug efficacy and lessen drug toxicity. This review focuses mainly on recently published research material. The cytochrome p450 enzymes, their role in metabolism, and their mechanisms of action are reviewed, and their role in drug-drug interactions are discussed. Drug-food and drug-herb interactions have garnered attention. Interdisciplinary communication among medical herbalists, medical doctors, and dietetic experts needs to be improved and encouraged. Internet resources for obtaining current information regarding drug-drug, drug-herb, and drug-nutrient interactions are provided.  相似文献   
78.
Evidence is accumulating that autocrine/paracrine regulatory mechanisms play an important role in regulating normal hematopoiesis. To support this, various growth factors, cytokines and chemokines are expressed and secreted by normal early and differentiated hematopoietic cells. In this review, we summarize recent advances in the identification and understanding of the role of autocrine/paracrine axes in normal human erythropoiesis. We will also address a biological significance of the secretion of (i) metalloproteinases which in addition to growth factors and cytokines are secreted by normal erythroid cells and (ii) membrane-derived microvesicles (MV), that are shed from the surface of maturating erythroblasts/reticulocytes, and as we postulate may also play a role in intercellular communication. We hypothesize that all these factors together play an important role in a crosstalk between erythroid cells and their environment. A better understanding of intercellular crosstalk operating in normal erythropoiesis and of the mechanisms regulating synthesis of these endogenously produced factors may allow us to develop more efficient therapeutic strategies to treat various erythropoietic disorders.  相似文献   
79.
In the search for the biological causes of schizophrenia and bipolar disorder, glutamate neurotransmission has emerged as one of a number of candidate processes and pathways where underlying gene deficits may be present. The analysis of chromosomal rearrangements in individuals diagnosed with neuropsychiatric disorders is an established route to candidate gene identification in both Mendelian and complex disorders. Here we describe a set of genes disrupted by, or proximal to, chromosomal breakpoints (2p12, 2q31.3, 2q21.2, 11q23.3 and 11q24.2) in a patient where chronic schizophrenia coexists with mild learning disability (US: mental retardation). Of these disrupted genes, the most promising candidate is a member of the kainate-type ionotropic glutamate receptor family, GRIK4 (KA1). A subsequent systematic case-control association study on GRIK4 assessed its contribution to psychiatric illness in the karyotypically normal population. This identified two discrete regions of disease risk within the GRIK4 locus: three single single nucleotide polymorphism (SNP) markers with a corresponding underlying haplotype associated with susceptibility to schizophrenia (P=0.0005, odds ratio (OR) of 1.453, 95% CI 1.182-1.787) and two single SNP markers and a haplotype associated with a protective effect against bipolar disorder (P=0.0002, OR of 0.624, 95% CI 0.485-0.802). After permutation analysis to correct for multiple testing, schizophrenia and bipolar disorder haplotypes remained significant (P=0.0430, s.e. 0.0064 and P=0.0190, s.e. 0.0043, respectively). We propose that these convergent cytogenetic and genetic findings provide molecular evidence for common aetiologies for different psychiatric conditions and further support the 'glutamate hypothesis' of psychotic illness.  相似文献   
80.
To cite this article: Mertens J, Stock S, Lüngen M, Berg AV, Kr?mer U, Filipiak-Pittroff B, Heinrich J, Koletzko S, Grübl A, Wichmann H-E, Bauer C-P, Reinhardt D, Berdel D, Gerber A. Is Prevention of Atopic Eczema with Hydrolyzed Formulas Cost-Effective? A Health Economic Evaluation from Germany. Pediatr Allergy Immunol 2012: 23: 597-604. ABSTRACT: Objective: The German Infant Nutritional Intervention (GINI) trial, a prospective, randomized, double-blind intervention, enrolled children with a hereditary risk for atopy. When fed with certain hydrolyzed formulas for the first 4?months of life, the risk was reduced by 26-45% in PP and 8-29% in intention-to-treat (ITT) analyses compared with children fed with regular cow's milk at age 6. The objective was to assess the cost-effectiveness of feeding hydrolyzed formulas. Patients and Methods: Cost-effectiveness was assessed with a decision tree model programmed in TreeAge. Costs and effects over a 6-yr period were analyzed from the perspective of the German statutory health insurance (SHI) and a societal perspective at a 3% effective discount rate followed by sensitivity analyses. Results: The extensively hydrolyzed casein formula would be the most cost-saving strategy with savings of 478?€ per child treated in the ITT analysis (CI95%: 12?€; 852?€) and 979?€ in the PP analysis (95%CI: 355?€; 1455?€) from a societal perspective. If prevented cases are considered, the partially whey hydrolyzed formula is cost-saving (ITT -5404?€, PP -6358?€). From an SHI perspective, the partially whey hydrolyzed formula is cost-effective, but may also be cost-saving depending on the scenario. An extensively hydrolyzed whey formula also included into the analysis was dominated in all analyses. Conclusions: For the prevention of AE, two formulas can be cost-effective or even cost-saving. We recommend that SHI should reimburse formula feeding or at least the difference between costs for cow's milk formula and the most cost-effective formula.  相似文献   
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