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71.
Despite the many studies documenting cerebral white matter microstructural alterations associated with very preterm birth (<32 weeks’ gestation), there is a dearth of similar research in moderate and late preterm infants (born 32–36 weeks’ gestation), who experience higher rates of neurodevelopmental delays than infants born at term (≥37 weeks’ gestation). We therefore aimed to determine whether whole brain white matter microstructure differs between moderate and late preterm infants and term-born controls at term-equivalent age, as well as to identify potential perinatal risk factors for white matter microstructural alterations in moderate and late preterm infants. Whole brain white matter microstructure was studied in 193 moderate and late preterm infants and 83 controls at term-equivalent age by performing Tract-Based Spatial Statistics analysis of diffusion tensor imaging data. Moderate and late preterm infants had lower fractional anisotropy and higher mean, axial and radial diffusivities compared with controls in nearly 70 % of the brain’s major white matter fiber tracts. In the moderate and late preterm group, being born small for gestational age and male sex were associated with lower fractional anisotropy, largely within the optic radiation, corpus callosum and corona radiata. In conclusion, moderate and late preterm infants exhibit widespread brain white matter microstructural alterations compared with controls at term-equivalent age, in patterns consistent with delayed or disrupted white matter microstructural development. These findings may underpin some of the neurodevelopmental delays observed in moderate and late preterm children.  相似文献   
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The paediatrician or family physician usually provides primary care for children diagnosed with cancer. Immunizations are an important facet of this care, but guidelines for the immunization of these immunocom-promised children are difficult to locate and cumbersome to follow. The authors have developed immunization guidelines for children receiving chemotherapy for cancer that will hopefully facilitate the care of this group of children. Before initiating any immunizations in this group of children, communication with a cancer specialist is recommended. There is little evidence-based literature to support immunization guidelines in immunocompromised hosts; thus, the recommendations presented are derived from the available literature, existing guidelines and expert opinion.  相似文献   
74.
PURPOSE: Sorafenib and erlotinib are potent, orally administered receptor tyrosine kinase inhibitors with antiproliferative and antiangiogenic activities. Given their inhibitory target profile and efficacy as single agents, the combination of these drugs is of considerable interest in solid malignancies. This study aimed to determine the recommended phase II dose of this targeted combination, their toxicity profile, pharmacokinetic interaction, and preliminary clinical activities. EXPERIMENTAL DESIGN: Sorafenib was administered alone for a 1-week run-in period, and then both drugs were given together continuously, with every 28 days considered as a cycle. Three dose levels were assessed. RESULTS: Seventeen patients with advanced solid tumors received 75 cycles of treatment. The most frequent adverse events of all grades were constitutional and gastrointestinal in nature followed by electrolytes and dermatologic toxicities. Fatigue was the most common adverse event (17 patients; 100%) followed by diarrhea (15 patients; 88%), hypophosphatemia (13 patients; 76%), and acneiform rash (12 patients; 71%). These adverse events were predominantly mild to moderate. The recommended phase II dose of this combination was determined as 400 mg twice daily sorafenib and 150 mg daily erlotinib. Pharmacokinetic analysis revealed no significant effect of erlotinib on the pharmacokinetic profile of sorafenib. Among 15 evaluable patients, 3 (20%) achieved a confirmed partial response and 9 (60%) had stable disease as best response. CONCLUSIONS: Sorafenib and erlotinib are well tolerated and seem to have no pharmacokinetic interactions when administered in combination at their full single-agent recommended doses. This well tolerated combination resulted in promising activity that needs further validation in phase II studies.  相似文献   
75.
The effects of fruiting body maturity on antioxidant activity and antioxidants production of the wild mushroom, Lactarius piperatus, were evaluated. Several biochemical assays were used to screen the antioxidant properties: reducing power, 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging capacity, inhibition of erythrocytes hemolysis mediated by peroxyl radicals and inhibition of lipid peroxidation using the beta-carotene linoleate model system. The amounts of phenols, flavonoids, ascorbic acid, beta-carotene and lycopene present in the immature, mature and degraded fruiting bodies were also determined. The highest antioxidant contents and the lowest EC(50) values for antioxidant activity were obtained in the mature stage with immature spores.  相似文献   
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77.
Microvascular changes in large flame burn wound in sheep   总被引:1,自引:0,他引:1  
Advances in local wound management with early excisional therapy have decreased morbidity and mortality of massive third-degree burn patients. Although blood redistribution within burned tissue is of clinical interest, few studies have longitudinally determined the regional blood flow of various layers of the burn wound. We used a conscious ovine model in which animals were subjected to 40% third degree burn. Burned tissue was divided into the four layers (i.e. skin, panniculus carnosus, adipose tissue, and skeletal muscle), and regional blood flow was determined separately, with fluorescent microspheres, while measuring systemic hemodynamics and total burned tissue microvascular fluid flux. The subburn adipose tissue exhibited a remarkable biphasic alteration in regional blood flow, whereas the skin layer showed only decreased blood flow during the whole experimental period. The increase in blood flow to the adipose tissue seems to be related to a sustained fluid filtrate in the postresuscitation period, resulting in edema formation mainly located in the adipose tissue at the endpoint.  相似文献   
78.
PURPOSE: The molecular basis of drug resistance in epilepsy is being explored. Two proteins associated with drug resistance in cancer, P-glycoprotein and multidrug resistance-associated protein 1, are upregulated in human epileptogenic pathologies. Other proteins associated with resistance in cancer include major vault protein (MVP) and breast cancer resistance protein (BCRP). We hypothesized that these proteins would also be upregulated in human epileptogenic pathologies. METHODS: Hippocampal sclerosis (HS), focal cortical dysplasia (FCD), and dysembryoplastic neuroepithelial tumor (DNT) were studied by using immunohistochemistry for MVP and BCRP. Nonepileptogenic control and histologically normal brain adjacent to epileptogenic tissue were used for comparison. RESULTS: MVP and BCRP were expressed ubiquitously in brain capillary endothelium. Ectopic upregulation of MVP was seen in hilar neurons in HS, dysplastic neurons in FCD, and lesional neurons in DNT. Only in HS cases were rare extralesional neurons immunoreactive. Glial upregulation was not seen. There was no qualitative upregulation of BCRP. CONCLUSIONS: These results show that more than one resistance protein may be upregulated in a given epileptogenic pathology and may contribute to drug resistance. Determination of the types, amounts, and distribution of such proteins will be necessary for rational treatment for drug resistance in epilepsy.  相似文献   
79.
BACKGROUND: Recent studies demonstrate a 98% accuracy of a CT scan in the diagnosis of acute appendicitis. We aimed to determine the accuracy and clinical value of CT scans in patients suspected of having acute appendicitis. PATIENTS AND MATERIALS: We reviewed outcomes of 125 patients over a 5-month period who had CT scans for the initial diagnosis of acute appendicitis. CT scan interpretations were correlated with surgical and pathologic findings. Follow-up was attempted in all patients who did not undergo appendectomy. RESULTS: CT scans and clinical courses were complete in 110 patients (88%); 14 patients were lost to follow-up and 1 was excluded. One patient had two CT scans. Thus, there were 111 CT scans available for review. Radiologic interpretation of these CT scans yielded 36 positive (33%), 67 negative (60%), and 8 indeterminate (7%), resulting in a sensitivity of 90%, a specificity of 89%, a PPV of 78%, and a NPV of 96%. CONCLUSIONS: CT scan may be useful in the diagnosis of acute appendicitis, but the reported high accuracy rate was not reproduced at our institution. CT scan was not clinically useful in 21% of patients. We conclude that a CT scan may be beneficial in the diagnosis of appendicitis with selected patients who have equivocal findings. Thus, at our institution, the accuracy of a CT scan does not justify its routine use in patients with clinical findings of appendicitis.  相似文献   
80.
Sex-linked dystonia parkinsonism (XDP) was reported by Lee et al. in 1975 occurring endemically in Panay, Philippines. It is an adult onset, sex-linked, predominantly male, severe, progressive movement disorder with high penetrance and a high frequency of generalization. The movement disorder is characterized by dystonic movements usually starting in the third or fourth decade, focal at the onset, spreading to generalization within 2-5 years. The dystonia co-exist or is replaced by parkinsonism usually beyond the 10th year of illness. As of June 2001, 376 XDP cases have been registered. One hundred and fifteen cases have died. The prevalence of XDP in the island of Panay is 5.24 per 100,000; 0.34/100,000 in the general population. The prevalence varies in the different provinces; it is highest in Capiz at 18.88/100,000, 7.46/100,000 in Aklan, 1.28 in Iloilo and 0.83 in Antique. The 376 cases are from 188 families and 92% of cases have positive family history. Ninety-nine percent of the cases are males. The mean age of onset is 39.48 years. Duration of illness is 12.95 years. Ninety-four percent of patients initially manifest with dystonic symptoms, while only 6% present with Parkinsonian traits. Among those presenting with dystonia, the initial presentation is in the lower extremities in 33%, craniofacial in 27%, cervical and shoulder in 25%, upper extremities in 14%, and trunk in 1%. Regardless of the site of onset, the dystonia spreads in 98% and generalizes within 5 years in 84%. Neuroimaging (magnetic resonance imaging, MRI) was done in 16 patients. In the patients who have just manifested the disease usually when dystonia predominates and parkinsonism is absent. MRI showed minimal atrophy of the caudate and putamen or subtle putaminal signal abnormality. In the late course, where Parkinsonism predominates, severe atrophy of the caudate and putamen as well as marked increase in signal abnormality are seen. There are six autopsied cases of XDP. Neuropathology revealed marked atrophy of the caudate and putamen mostly in the cases with longstanding illness. The sex-linked pattern of inheritance has been established. Genetic studies have located the affected gene (DYT3) to Xq13.1. Nemeth's group has mapped the XDP gene to a <350 kb locus in the DXS 7117-DX 559 region. To date, no treatment has been proven consistently effective.  相似文献   
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