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61.
Correlation between the measurement of posterior capsule opacification severity and visual function testing 总被引:2,自引:0,他引:2
PURPOSE: To develop software to measure the severity of posterior capsule opacification (PCO) using analysis of retroillumination images and to correlate the results with clinical evaluation of PCO severity and visual function. SETTING: Department of Physics, King's College, and Department of Ophthalmology, St. Thomas' Hospital, London, United Kingdom. METHODS: A technique for calculating PCO severity was developed based on calculating the variance of intensity by transforming retroillumination images to a similar mean intensity. The computer-derived severity was compared to grading of clinical severity by 3 independent observers using a library of 100 retroillumination images ranging from clear posterior capsules to very severe PCO. The computer results were also compared with the following other current methods of measuring PCO: Evaluation of Posterior Capsule Opacification (EPCO), POCOman, and Automated Quantification of After-Cataract. A further 35 images were used to compare the results of computer-derived severity with the results of visual function analysis (high-contrast acuity, 100%; low-contrast acuity, 9%) using the Early Treatment Diabetic Retinopathy Study chart, contrast sensitivity testing using the Pelli-Robson chart, and glare assessment using the van den Berg straylight meter. RESULTS: The severity scores showed a good correlation with clinical severity scores for the library of images (r=0.86) and with severity scores using POCOman and EPCO (r=0.85 and r=0.81, respectively). The correlations with visual function tests were also good, with low-contrast visual acuity (9%) showing the best correlation (r=0.87). CONCLUSION: Variance in intensity of PCO was successfully used to calculate the severity of PCO. 相似文献
62.
63.
AIMS: To establish the value of vimentin expression in predicting survival in patients with breast cancer. METHODS: Five-year follow-up data were obtained for 68 patients with ductal carcinoma (NOS) of the breast in whom vimentin expression had been studied in fresh frozen and formalin-fixed, paraffin-embedded tissue. The predictive value on survival of tumour size, growth fraction (as assessed using the Ki67 monoclonal antibody), oestrogen receptor status and Bloom and Richardson grade of the primary tumour, and the presence or absence of lymph node metastases in axillary samples, were also studied. RESULTS: Twenty-two patients died of their disease within 5 years of diagnosis. Vimentin expression either on frozen or paraffin sections did not provide a statistically significant prediction of survival. On univariate analysis tumour grade, size and the presence of lymph node metastases provided prognostic information. Only lymph node status was of independent prognostic importance on multivariate analysis. CONCLUSIONS: Whilst these results confirm the value of established prognostic factors, they do not support the use of vimentin expression in either fresh or fixed tissue for the prediction of survival in ductal carcinoma (NOS) of the breast. 相似文献
64.
Heatley MK 《Histopathology》2008,52(3):267-276
Aims: To compare the relative risk of antigen expression being detected immunohistochemically in ovarian and gastric carcinoma aggregated from studies performed for diagnostic purposes, with the relative risks of their expression in all patients in the English literature.
Methods and results: Both types of series indicated that cytokeratin (CK) 7 expression was greater and that of CK20 and carcinoembryonic antigen less in ovarian than in gastric carcinoma ( P < 0.05). Synthesis of all data available for MUC-2 suggested it was more commonly expressed in ovarian carcinoma, whereas the relative risk in papers that directly compared its expression suggested that it was more common in the gastric carcinoma ( P = 0.2, NS). Aggregating all possible data suggested villin was more likely to be expressed in ovarian cancers, whereas studies in which its expression was compared directly in both tumours suggested the opposite. Although statistically significant, patient numbers were small.
Conclusion: Provided sufficient numbers of cases are studied, analysis of studies comparing antigen expression for diagnostic purposes in tumours from two body sites is likely to be supported in the wider literature. The design of such comparative studies is informed by aggregating data from single tumour studies. 相似文献
Methods and results: Both types of series indicated that cytokeratin (CK) 7 expression was greater and that of CK20 and carcinoembryonic antigen less in ovarian than in gastric carcinoma ( P < 0.05). Synthesis of all data available for MUC-2 suggested it was more commonly expressed in ovarian carcinoma, whereas the relative risk in papers that directly compared its expression suggested that it was more common in the gastric carcinoma ( P = 0.2, NS). Aggregating all possible data suggested villin was more likely to be expressed in ovarian cancers, whereas studies in which its expression was compared directly in both tumours suggested the opposite. Although statistically significant, patient numbers were small.
Conclusion: Provided sufficient numbers of cases are studied, analysis of studies comparing antigen expression for diagnostic purposes in tumours from two body sites is likely to be supported in the wider literature. The design of such comparative studies is informed by aggregating data from single tumour studies. 相似文献
65.
66.
Structural abnormalities of the X chromosome are rarely found in neoplastic disorders. We describe three patients with a history of idiopathic acquired sideroblastic anemia (IASA); each one had an abnormal clone of cells in the bone marrow, characterized by a structurally abnormal X chromosome. In two of these patients, the predominant karyotype was 47,X,2idic(X)(q13); in the other patient, it was 46,X,t(X;11)(q13;p15). Inasmuch as all three of these cases involved chromosome band Xq13, as did two previously published cases, we suggest that band Xq13 may be more prone to structural rearrangement than other X chromosome bands in hematologic disorders. The common Xq13 chromosome breakpoint and clinical presentation (IASA) among these three patients and the occurrence of an X-linked type of sideroblastic anemia may suggest that an association exists between X chromosome abnormalities and IASA. Perhaps alteration of a gene or chromosome structure in or near band Xq13 predisposes to development of IASA. The fact that two of these patients had preleukemia and the third had overt acute leukemia may imply that patients with IASA and X chromosome abnormalities have a poor prognosis. Cases of IASA without associated X chromosome abnormalities are known; thus, if an association between IASA and an abnormal X chromosome does exist, most likely it involves only some patients with IASA. 相似文献
67.
The effects on the oesophagus of an aromatic oil, guaiacol, has been examined in a group of 20 patients with reflux oesophagitis and also normal volunteers. This agent produced a rapid and sustained rise in resting lower oesophageal sphincter pressures and the peristaltic pressures induced in response to swallowing liquids. This compound may prove useful in the treatment of patients with reflux oesophagitis and other disorders of oesophageal motility. 相似文献
68.
Eosinophils in the rectal mucosa. A simple method of predicting the outcome of ulcerative proctocolitis? 下载免费PDF全文
One-hundred-and-thirteen rectal biopsies and 17 total colectomy specimens from 50 patients with ulcerative proctocolitis were examined. These patients had been followed for periods up to 220 months, mean 70 months. The histological changes were compared with the clinical features of the disease. Patients with relatively benign disease which responded to treatment had significantly raised eosinophil counts in the mucosa examined, compared with patients who had aggressive disease which failed to respond to medical treatment (P less than 0.001). Tissue eosinophilia in the rectal mucosa may provide a simple method for predicting the clinical course of patients with ulcerative proctocolitis. 相似文献
69.
Activation of the CPP32 protease in apoptosis induced by 1-beta-D- arabinofuranosylcytosine and other DNA-damaging agents 总被引:2,自引:0,他引:2
The response of human myeloid leukemia cells to treatment with 1-beta- arabinofuranosylcytosine (ara-C) includes the induction of apoptosis. Ara-C induced apoptosis is associated with proteolytic cleavage of poly(ADP-ribose) polymerase (PARP) and protein kinase C (PKC) delta. However, the signals involved in this response are unknown. The present studies show that ara-C treatment of U-937 cells is associated with induction of a protease activity that cleaves the tetrapeptides Ac-DEVD- pNA and Ac-DMOD-pNA found at the cleavage sites of PARP and PKC delta, respectively. The ara-C-induced protease activity was sensitive to overexpression of the anti-apoptotic protein Bcl-xL and the baculovirus protein p35. By contrast, overexpression of the cowpox virus protein CrmA blocked apoptosis induced by engagement of the Fas receptor but not that induced by ara-C. CrmA overexpression also had no detectable effect on ara-C-induced cleavage of PKC delta. The results further show that ara-C induces activation of the CPP32 protease by a CrmA- insensitive and p35-sensitive mechanism. Similar results were obtained with cisplatinum, etoposide, and camptothecin. These findings indicate that ara-C and other DNA-damaging agents activate a CrmA-insensitive apoptotic pathway involving CPP32 and that these signals differ from those associated with apoptosis induced by the Fas receptor. 相似文献
70.
Systemic and local antibody responses to gastric Campylobacter pyloridis in non-ulcer dyspepsia. 总被引:35,自引:2,他引:35 下载免费PDF全文
B J Rathbone J I Wyatt B W Worsley S E Shires L K Trejdosiewicz R V Heatley M S Losowsky 《Gut》1986,27(6):642-647
Antibody titres to Campylobacter pyloridis in serum and gastric juice were estimated by an enzyme linked immunosorbent assay (ELISA) to whole organisms obtained from bacterial culture in 39 patients with non-ulcer dyspepsia. Whereas 20 of the 21 patients with chronic gastritis had gastric C pyloridis, 17 patients with no C pyloridis had normal histology in the gastric antrum and body. Significantly raised serum IgG and IgA antibody titres to C pyloridis were found in colonised patients with gastritis. Patients with raised IgG antibody to C pyloridis were also shown to have significantly raised titres to other Campylobacter species, suggesting antigenic cross reactivity. Gastric juice antibodies were also studied and IgA titres to C pyloridis were detected in a proportion of patients with gastritis, together with low levels of IgM, but no IgG. 相似文献