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AIMS: To analyse the significance of antibodies to p53 protein as a serological marker for changes in p53 gene expression in patients with hepatocellular carcinoma. METHODS: Thirty eight patients with hepatocellular carcinoma, 19 showing accumulation of p53 protein by immunohistochemistry and 19 having no accumulation, were studied. The presence of anti-p53 was tested using a novel ELISA utilising a recombinant p53 protein as a capture system and verified by western blotting. p53 gene mutations were sought by single strand conformational polymorphism and DNA sequencing analyses. RESULTS: Of 19 patients with p53 protein accumulation in tumour tissue, 10 (52%) had antibodies to p53 in serum by ELISA. Four patients with p53 negative immunohistochemistry also had detectable anti-p53. Western blot analysis confirmed the specificity of the ELISA positive serum samples. The presence of anti-p53 was independent of serum alpha-fetoprotein and was detected in 50% of small tumours while only 8% were alpha-fetoprotein positive. Mutations affecting exons 5 and 6 seem to be more frequently associated with development of anti-p53, than mutations in exons 7 or 8. CONCLUSIONS: The ELISA for anti-p53 is a convenient and specific tet for the detection of humoral response to alterations in p53 gene expression and could be of value in the diagnosis and characterisation of patients with hepatocellular carcinoma.  相似文献   
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The concomitant influence of surface roughness and fluorhydroxyapatite (FHA) coating of titanium (Ti) implants on bone response was investigated. For this purpose, titanium screw-shaped implants with a lower degree (Y371) and a higher degree (TiPore300) of surface roughness, coated with FHA and uncoated, were transversally inserted into the diaphyses of sheep tibiae for 12 weeks. Four sheep received Y371 (group A) and Y371 + FHA (group B) screws and four sheep received TiPore300 (group C) and TiPore300 + FHA (group D) screws. For each type of material, the morphology and microstructure of implant-facing bone were evaluated. The host bone of each tibia was used as a control. In all groups the bone tissue did not reach a complete maturation. The higher degree of roughness, perhaps due to an excessive irregularity of the surface, induced the worst osteointegration: a fibrous tissue layer between screw and new bone tissue was often present. Nevertheless, as viewed by XRD, no crystallographic change of the apatite lattice was observed in any of the implants. In contrast, the microhardness value, an index of bone mineralization, was higher in the uncoated screws and decreased progressively in the following order: group C > group A > group B > group D. The association of plasma spraying with roughness treatment constitutes a complex system that seems to interfere with bone mineralization. A chemical change of the surface, perhaps with more Ti release or more coating degradation, could be responsible for such impairment. The authors emphasize the necessity for simultaneous evaluation of surface topography and chemistry as well as an improvement in plasma-spraying and post-processing techniques and in standard procedures for materials characterization.  相似文献   
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Sexual dysfunction is a well-known complication of chronic somatic illness. Eighty-six consecutive epileptic outpatients, 38 men and 48 women, without accompanying disorders, were studied. The frequency and symptoms of sexual dysfunction were compared with results from previous studies using identical sexological methodology. The previous studies were of diabetic patients and healthy controls. Eight percent of the epileptic men reported a sexual dysfunction compared to 44% of the diabetics and 13% of the controls. Epileptic women, diabetic women, and controls showed no significant differences in sexual dysfunction (29%, 28%, and 25%, respectively). In both sexes, the sexual function measured by frequencies of coitus and masturbation was normal. Most patients had good control of epileptic attacks on a treatment of monotherapy. Hormonal status was generally within normal limits in both men and women; only a few minor differences were found and they showed no correlation with sexual dysfunction. Psychologically and socially the patients did not differ appreciably from normals, and they exhibited a high degree of disease acceptance. This study, using a biopsychosocial approach in understanding sexual dysfunctions, is in contrast with previous, mainly uncontrolled, studies of epileptic patients that reported high frequencies of hyposexuality in males. We conclude that epilepsy does not necessarily increase the risk of sexual dysfunction in male or female.  相似文献   
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In the last 10 years, four patients with aneurysms of the supraaortic trunks and the internal carotid artery have been operated in emergency at Department of Vascular Surgery of University of Bari. The first case was a mycotic aneurysm of the carotid bifurcation, the second an aneurysm of internal carotid artery interesting the retropharynx, the third a post-operatory pseudoaneurysm of common carotid in a patient affected by Takayasu's disease and the last an atherosclerotic aneurysm of the innominate artery. Clinical picture suggested an immediate surgical treatment in all patients. Different procedure were used depending on size and localization of each lesion. Results in all cases have been satisfactory. The aneurysms of supraaortic trunks and of internal carotid artery are very rare; therefore when clinical picture is dramatic or quickly worsening, emergency treatment is mandatory in order to reduce mortality risk and minimize complications.  相似文献   
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Nanoporous Au has been subjected to serial block face-scanning electron microscopy (SBF-SEM) 3D-characterisation. Corresponding sections have been digitalized and used to evaluate the associated mechanical properties. Our investigation demonstrates that the sample is homogeneous and isotropic. The effective Young’s modulus estimated by an analytical multiscale approach agrees remarkably well with the values stated in the literature.  相似文献   
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ObjectivesThe aim of this study was to assess the prevalence of delirium, using the Assessment Test for Delirium and Cognitive Impairment (4AT) in end-of-life palliative care patients.Subjects and MethodsThis retrospective cross-sectional study was conducted on end-of-life patients in a hospice or at home. All patients were evaluated with the 4AT for the presence of delirium.ResultsOf the 461 patients analyzed, 76 (16.5%) were inpatients and 83.5% (385) outpatients. The median age was 79.5 (72–86) years, and 51.0% were female. According to the 4AT score, 126 patients (27.3%) had delirium (A4T ≥4) at admission, 28 (36.8%) were inpatients, and 98 (25.5%) outpatients. Around 33.8% of the cancer inpatients had delirium, while 20.6% of the cancer outpatients had delirium. The prevalence of delirium varied according to the setting, clinical condition, and life expectancy. In addition, 55.0% (11) actively dying inpatients, within 3 days, had delirium, and 56.7% (17) outpatients had delirium; while among those with life expectancy longer than 4 days, 30.4% (17) inpatients and 22.8% (81) outpatients were with delirium.ConclusionsOur study confirms that delirium is common in cancer and noncancer palliative care patients. Further research on delirium in end-of-life palliative care patients should consider the complexity of palliative care of this population as well as of the characteristics of the settings.  相似文献   
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Intoxication with lead (Pb) results in increased blood pressure by mechanisms involving matrix metalloproteinases (MMPs). Recent findings have revealed that MMP type two (MMP‐2) seems to cleave vasoactive peptides. This study examined whether MMP‐2 and MMP‐9 levels/activities increase after acute intoxication with low lead concentrations and whether these changes were associated with increases in blood pressure and circulating endothelin‐1 or with reductions in circulating adrenomedullin and calcitonin gene‐related peptide (CGRP). Here, we expand previous findings and examine whether doxycycline (a MMPs inhibitor) affects these alterations. Wistar rats received intraperitoneally (i.p.) 1st dose 8 μg/100 g of lead (or sodium) acetate, a subsequent dose of 0.1 μg/100 g to cover daily loss and treatment with doxycycline (30 mg/kg/day) or water by gavage for 7 days. Similar whole‐blood lead levels (9 μg/dL) were found in lead‐exposed rats treated with either doxycycline or water. Lead‐induced increases in systolic blood pressure (from 143 ± 2 to 167 ± 3 mmHg) and gelatin zymography of plasma samples showed that lead increased MMP‐9 (but not MMP‐2) levels. Both lead‐induced increased MMP‐9 activity and hypertension were blunted by doxycycline. Doxycycline also prevented lead‐induced reductions in circulating adrenomedullin. No significant changes in plasma levels of endothelin‐1 or CGRP were found. Lead‐induced decreases in nitric oxide markers and antioxidant status were not prevented by doxycycline. In conclusion, acute lead exposure increases blood pressure and MMP‐9 activity, which were blunted by doxycycline. These findings suggest that MMP‐9 may contribute with lead‐induced hypertension by cleaving the vasodilatory peptide adrenomedullin, thereby inhibiting adrenomedullin‐dependent lowering of blood pressure.  相似文献   
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