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OBJECTIVE: Phospholipases A2 (PLA2) are a family of enzymes involved in membrane phospholipid metabolism and cell signalling. The gene encoding one form, type VI calcium-independent phospholipase A2, is located in a region of DNA that may contain a gene important in the aetiology of psychosis. Moreover, the activity of calcium-independent PLA2 is reported to be elevated in the blood and brain of patients with schizophrenia. In this study we determined whether a similar change takes place in patients with bipolar disorder with and without a history of psychosis. METHODS: Serum calcium-independent and -dependent PLA2 activities were determined in 24 patients with bipolar I disorder. RESULTS: Serum calcium-independent and -dependent PLA2 activities in bipolar cases did not differ significantly from that in healthy volunteers (HVs). However, calcium-independent PLA2 activity was significantly (p < 0.05) higher in patients with a history of psychosis compared with those with no history of psychosis (by 55%) or to HVs (by 31%). CONCLUSIONS: Our data suggest that a subset of bipolar I disorder patients with a history of psychosis have elevated calcium-independent PLA2 activity. Given that this enzyme activity is also increased in schizophrenia, elevated rates of phospholipid turnover mediated by the enzyme could represent a common biochemical feature of psychotic illness.  相似文献   
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RATIONALE: A small percentage of patients with idiopathic generalized epilepsy (IGE) do not respond to medical therapy. Generalized tonic-clonic (GTC) seizures are especially debilitating and can be associated with severe injuries. The benefit, safety and effect of corpus callosotomy (CC) in patients with IGE have not been studied. METHODS: We reviewed patients with presumed IGE who underwent CC between 1991 and 2000. Criteria for selection included history, examination, brain imagining, interictal and ictal EEG. All patients had refractory and debilitating tonic-clonic seizures (GTCS) and had failed four or more antiepileptic drugs. Seizure frequency was calculated per month over the last year and pre-operative baseline was compared to last follow-up using paired t-tests. IQ, executive function, language and verbal, non-verbal memory and quality of life (QOL) was compared before and after surgery. Serial EEGs after surgery were reviewed. RESULTS: There were nine patients (seven men), mean age 37.9 (range: 22-49), mean IQ 87.3 (range: 75-107). All had anterior CC. Mean follow-up time was 5.4 years (range: 0.6-10.3 years). One patient died from sudden death in epilepsy 9 months after surgery. There was a significant reduction of GTC seizures from 6.3 to 1.1 (p<0.005). Four patients had more than 80% and eight more than 50% reduction. Of five patients with absence seizures, two became seizure free and one had more than 80% reduction and two worsened slightly, and of three with myoclonic seizures one had more than 90% reduction. One patient had completion of the CC with improvement of myoclonus and absence seizures, but not of GTC seizures and suffered a disconnection syndrome. Another had right frontal focal resection without improvement after new seizures of focal onset. Cognitive testing showed a good outcome (improved or no change) in all cognitive domains. Post-surgical EEG showed new focal slowing and sharp waves. There was no change in QOL. CONCLUSION: CC can be effective in reducing GTC, absence and myoclonic seizures in patients with refractory IGE. These findings suggest that interhemispheric communication of the cerebral cortices plays an important role in the generation of seizures in IGE. Anterior CC appears safe while complete callosotomy has a risk of disconnection syndrome.  相似文献   
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OBJECTIVE: To prepare, sequence and analyse adult human cartilage cDNA libraries to study the gene expression pattern between normal and osteoarthritic cartilage. METHODS: Poly A(+)RNA from adult human normal and osteoarthritic articular cartilage was isolated and used to prepare cDNA libraries. Approximately 5000 ESTs from each library were sequenced and analysed using bioinformatic tools. The expression of select genes was confirmed by Northern blot and in situ hybridization analysis. RESULTS: Multiple gene families including several classical cartilage matrix protein encoding genes were identified. Approximately 28-40% of the genes sequenced from these libraries were novel, while half of the genes encoded known proteins and 4-6% of the genes encoded novel homologs of known proteins. Several known genes, whose expression has not been reported previously in cartilage, were also identified. We have confirmed the cartilage expression of three known (CTGF, CTGF-L and clusterin) and two novel homologs of known genes (PCPE-2 and Gal-Nac transferase) by Northern blot and in situ hybridization analysis. CONCLUSION: This is the first report of the preparation and sequencing of cDNA libraries from adult human normal and osteoarthritic articular cartilage. Further analysis of genes identified from these libraries may provide molecular targets for diagnosis and/or treatment of osteoarthritis (OA).  相似文献   
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OBJECTIVES: To investigate the in vitro effects of Sodium Tetradecyl Sulphate (STS) and Polidocanol (POL) on clotting tests, clotting factors, platelets and microparticles. MATERIALS AND METHODS: Platelet rich (PRP) and platelet poor (PPP) plasmas were incubated with varying concentrations of STS and POL. Clotting tests, platelet/plasma turbidity, and microparticle studies were performed. Specimens were mixed with individual factor deficient plasmas and clotting factor activities were studied. RESULTS: STS at high concentrations (>0.3%) destroyed platelets, microparticles and the clotting factors V, VII and X. It prolonged all clotting tests including prothrombin time (PT), activated partial thromboplastin time (APTT), non-activated partial thromboplastin time (NAPTT), thrombin time (TT), factor Xa clotting time (XACT) and surface activated clotting time (SACT). Higher concentrations of POL were required to achieve some anticoagulant activity. Low sclerosant concentrations shortened XACT and SACT, and induced release of procoagulant platelet derived microparticles. Increased exposure time resulted in increased procoagulant activity. STS at concentrations higher than 0.5% precipitated a complex containing apolipoprotein b and fibrinogen. CONCLUSIONS: Detergent sclerosants affect the clotting mechanism by interfering with clotting factor activities, procoagulant phospholipids and platelet derived microparticles. STS has more anticoagulant activity than POL in high concentrations. Low concentration sclerosants demonstrate procoagulant activity.  相似文献   
58.

Aims

Smartphone technology and downloadable applications (apps) have created an unprecedented opportunity for access to medical information and healthcare-related tools by clinicians and their patients. Here, we review the current smartphone apps in relation to hernias, one of the most common operations worldwide. This article presents an overview of apps relating to hernias and discusses content, the presence of medical professional involvement and commercial interests.

Methods

The most widely used smartphone app online stores (Google Play, Apple, Nokia, Blackberry, Samsung and Windows) were searched for the following hernia-related terms: hernia, inguinal, femoral, umbilical, incisional and totally extraperitoneal. Those with no reference to hernia or hernia surgery were excluded.

Results

26 smartphone apps were identified. Only 9 (35 %) had named medical professional involvement in their design/content and only 10 (38 %) were reviewed by consumers. Commercial interests/links were evident in 96 % of the apps. One app used a validated mathematical algorithm to help counsel patients about post-operative pain.

Conclusions and opportunities

There were a relatively small number of apps related to hernias in view of the worldwide frequency of hernia repair. This search identified many opportunities for the development of informative and validated evidence-based patient apps which can be recommended to patients by physicians. Greater regulation, transparency of commercial interests and involvement of medical professionals in the content and peer-review of healthcare-related apps is required.  相似文献   
59.
While the role of childhood adversity in increasing the risk of psychosis has been extensively investigated, it is not clear what the impact of early adverse experiences is on the outcomes of psychotic disorders. Therefore, we investigated associations between childhood adversity and 1-year outcomes in 285 first-presentation psychosis patients. Exposure to childhood adversity prior to 17 years of age was assessed using the Childhood Experience of Care and Abuse Questionnaire. Data on illness course, symptom remission, length of psychiatric hospitalization, compliance with medication, employment, and relationship status were extracted from clinical records for the year following first contact with mental health services for psychosis. Seventy-one percent of patients reported exposure to at least 1 type of childhood adversity (physical abuse, sexual abuse, parental separation, parental death, disrupted family arrangements, or being taken into care). No robust associations were found between childhood adversity and illness course or remission. However, childhood physical abuse was associated with almost 3-fold increased odds of not being in a relationship at 1-year follow-up compared to patients who did not report such adverse experiences. There was also evidence of a significant association between parental separation in childhood and longer admissions to psychiatric wards during 1-year follow-up and 2-fold increased odds of noncompliance with medication compared to those not separated from their parents. Therefore, our findings suggest that there may be some specificity in the impact of childhood adversity on service use and social functioning among psychosis patients over the first year following presentation to mental health services.Key words: first episode, illness course, psychosis, trauma, psychotic symptoms, service use  相似文献   
60.
Differences in behavioral roles, anatomical connectivity, and gene expression patterns in the dorsal, intermediate, and ventral regions of the hippocampus are well characterized. Relatively fewer studies have, however, focused on comparing the physiological properties of neurons located at different dorsoventral extents of the hippocampus. Recently, we reported that dorsal CA1 neurons are less excitable than ventral neurons. There is little or no information for how neurons in the intermediate hippocampus compare to those from the dorsal and ventral ends. Also, it is not known whether the transition of properties along the dorsoventral axis is gradual or segmented. In this study, we developed a statistical model to predict the dorsoventral position of transverse hippocampal slices. Using current clamp recordings combined with this model, we found that CA1 neurons in dorsal, intermediate, and ventral hippocampus have distinct electrophysiological and morphological properties and that the transition in most (but not all) of these properties from the ventral to dorsal end is gradual. Using linear and segmented regression analyses, we found that input resistance and resting membrane potential changed linearly along the V–D axis. Interestingly, the transition in resonance frequency, rebound slope, dendritic branching in stratum radiatum, and action potential properties was segmented along the V–D axis. Together, the findings from this study highlight the heterogeneity in CA1 neuronal properties along the entire longitudinal axis of hippocampus. © 2015 Wiley Periodicals, Inc.  相似文献   
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