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71.
In this study we investigated the immunohistochemical expression of inducible nitric oxide synthase (iNOS) in a set of normal pleural mesothelial tissues, malignant mesotheliomas, mesothelioma cell lines and metastatic pleural adenocarcinomas. Furthermore, the expression of mRNA was assessed in four malignant mesothelioma cell lines in culture. Apoptosis and vascular density in malignant mesotheliomas was assessed by the TUNEL method and by immunohistochemistry with an antibody against FVIII-related antigen. Immunohistochemically mesothelial cells in non-neoplastic healthy pleural tissues were mostly negative for iNOS. Positivity for iNOS was observed in 28/38 (74%) and 24/25 (96%) of malignant mesotheliomas and metastatic pleural adenocarcinomas, respectively. Epithelial and mixed mesotheliomas expressed more often strong iNOS immunoreactivity compared to the sarcomatoid subtype (P = 0.023). Moreover, metastatic adenocarcinomas expressed more often iNOS positivity than mesotheliomas (P = 0.021). Experiments with the cell lines confirmed that malignant mesothelioma cells are capable of synthesizing iNOS. No significant association was found between iNOS expression and apoptosis or vascular density in malignant mesotheliomas. The higher expression of iNOS in the epithelial subtype of mesothelioma and pleural metastatic adenocarcinoma might be due to an increased sensitivity of these cell types to cytokine-mediated iNOS upregulation. The strong expression of iNOS suggests a putative role for NO in the growth and progression of these tumours.  相似文献   
72.
Matrix metalloproteinases (MMPs) are involved in tumor growth and spreading. Here, we investigated the tumor immunoreactive protein of MMP-2, MMP-9 and TIMP-1 as well as the levels of circulating total TIMP-1 and MMP-2/TIMP-2-complex as prognostic factors in lung cancer patients. The material included 59 patients, 30 with a squamous cell carcinoma, 21 with an adenocarcinoma and eight with other histology. Circulating antigens were measured by ELISA assay and the protein expression in primary tumors was analyzed by streptavidin-biotin immunohistochemical staining using specific monoclonal antibodies. The strong positivity for MMP-2 or MMP-9 in tumor predicted poor prognosis. The 5-year survival rates were 83 or 85% in patients negative for MMP-2 or MMP-9, respectively. Only 17% of the patients with a tumor highly positive for MMP-2 and 43% of those with a high positivity for MMP-9 survived at that time (Cox regression P=0.042 for MMP-2 and log rank P=0.046 for MMP-9). On the contrary, strong tissue positivity for TIMP-1 demonstrated a tendency for a favorable survival, although the difference did not reach statistical significance. In patients with a squamous cell carcinoma Stage I, low serum TIMP-1 (or=300 ng/ml) associated with an increased survival rate, the 5-year survival being 81 versus 34% (log rank P=0.069) in patients with high or low serum levels for MMP-2/TIMP-2-complex, respectively. Tissue MMP-2 correlated to high expression of MMP-9 immunoreactive protein (P=0.003), but the serum levels of MMP-2/TIMP-2-complex or TIMP-1 did not correlate to the immunostaining of the corresponding tumors. We conclude that in lung carcinoma the best prognostic value is achieved by using immunohistochemistry for MMP-2 and MMP-9. In early disease, however, serum TIMP-1 or MMP-2/TIMP-2-complex could offer some further prognostic value.  相似文献   
73.
Accumulation of the tumour suppressor gene p53 product due to a gene mutation is frequently seen in human carcinomas, including lung carcinoma. Another indirect mechanism involving p53 in malignant growth relates to the E6 protein of the human papillomavirus (HPV), which is able to bind and degrade wild-type p53 protein, thus eliminating its tumour suppressor activities. Bronchiolo-alveolar carcinoma (BAC) is a rare type of lung carcinoma. The aim of our study was to examine the occurrence of p53 accumulation and the presence of HPV DNA in BAC. Sections of 22 BACs were immunohistochemically stained using a p53 antibody, CM-1. The presence of HPV DNA in BACs was verified by in situ hybridisation for HPV types 6, 11, 16, 18, 31 and 33 and confirmed by PCR. Thirty-six percent of the tumours showed abnormal p53 nuclear accumulation, and HPV DNA, revealed by in situ hybridisation, was found in 36%. Unexpectedly, only 13% of the type 1 BACs were positive for p53, whereas 45% of the type 2 BACs were positive. During a follow-up of 12-176 months, only 10% of the patients with BACs negative for both p53 and HPV died of the disease, compared with 42% of the patients with either p53 or HPV positivity. No inverse relationship between abnormal p53 protein accumulation and the presence of HPV DNA was found. © 1995 Wiley-Liss, Inc.  相似文献   
74.
The incidence of and mortality from squamous cell carcinoma (SCC) of the tongue have increased during the recent decades in the Western world. Much effort has been made to predict tumour behaviour, but we still lack specific prognostic indicators. The aim of our study was to evaluate the relative importance of the known demographic, clinical and histological factors in a homogeneous population-based group of patients with SCC of the mobile tongue. The demographic and clinical factors were reviewed retrospectively from primary and tertiary care patient files. Histological prognostic factors were determined from pre-treatment biopsies. The TNM stage was found to be the most important prognostic factor. In particular, local spread outside the tongue rather than spread to regional lymph nodes was related to poor prognosis. Several demographic and histopathological factors were closely related to TNM stage. When the cases were divided into stage I-II carcinomas and stage III-IV carcinomas, it appeared that the patient's older age (> 65 years), a high malignancy score and an absence of overexpressed p53 protein were associated with a poorer prognosis in stage I-II carcinomas. Such cases may require more aggressive treatment. Among patients with stage III-IV carcinomas, heavy use of alcohol was significantly associated with a poor disease-specific survival time.  相似文献   
75.
In this report we have investigated levels of prostatic acid phosphatase (PAP) and prostate-specific antigen (PSA) gene expression in prostatic carcinoma (Ca) and benign prostatic hyperplasia (BPH) specimens. Northern-blot analyses of total prostatic mRNA indicated that there was a tendency towards lower amounts of PAP mRNA and PSA mRNA in the Ca specimens than in the BPH specimens, although, because of the great variation in the expression levels of both mRNAs, these differences were not statistically significant. In situ hybridization analyses clearly showed that both PAP and PSA mRNAs were confined to the columnar epithelial cells and that stromal cells were devoid of these mRNAs. In addition, PAP and PSA mRNAs were more abundant in BPH tissue than in adjacent Ca tissue within the same specimen. The levels of PAP and PSA enzymes were analyzed immunohistochemically using a bispecific antibody having high affinity for both PAP and PSA, and the results were compared with those obtained using monoclonal anti-PAP and anti-PSA antibodies. All 3 antibodies stained only epithelial cells and BPH tissue consistently gave more intense staining than Ca tissue. Furthermore, the anti-PSA and the bispecific anti-PAP-PSA antibodies stained well or moderately differentiated Ca tissues more strongly than poorly differentiated Ca tissues. No PSA staining was detected in 3 and no PAP staining in 5 of the moderately or poorly differentiated carcinomas (grades II or III). Our results show that, in comparison with BPH tissue, prostatic Ca tissue is associated with significantly lower levels of mRNAs coding for the prostatic marker enzymes PAP and PSA, as well as with lower concentrations of these enzymes. Furthermore, dedifferentiation of prostate Ca is associated with a decrease in the level of intraprostatic PSA.  相似文献   
76.
We retrospectively analyzed the rate and character of complications in a series of 100 consecutive external fixation tests during 1985-1991. There were 30 complications in 25 patients. The most common was pin tract infection, which was definite in 12 cases and probable in 6. Altogether 12 patients developed complications that resulted in removal or reapplication of the device. 8 cases had an incorrect position of a Schanz screw; 3 of these had neurological complications. The only variable having a significant association with complications was the duration of the test. Because of this complication rate, the indications for the test should be carefully considered.  相似文献   
77.
BACKGROUND: In some carcinomas inactivation of the tumour suppressor gene product p53, either by point mutation or indirectly by the human papillomavirus (HPV), has been suggested as two alternative routes to malignant transformation. To test this hypothesis in lung tumours, 43 lung carcinomas were analysed by in situ hybridisation and polymerase chain reaction (PCR) for the presence of HPV DNA, and the results were compared with p53 protein immunohistochemical analysis. METHODS: The presence of HPV DNA in lung carcinoma was detected by nucleic acid in situ hybridisation for HPV types 6, 11, 16, 18, 31, and 33 using nonradioactively labelled DNA probes. Polymerase chain reaction (PCR) analysis was performed on all cases showing positive HPV DNA labelling by in situ hybridisation and in an additional 13 negative cases. Abnormal nuclear accumulation of the p53 protein was revealed by immunohistochemistry using the avidin-biotin-peroxidase complex method and a CM-1 polyclonal anti-human p53 antibody and a monoclonal mutation-specific Pab 240 p53 antibody. RESULTS: HPV DNA was found by in situ hybridisation in 13 lung carcinomas (30%). In all these cases subtype-specific HPV DNA could also be detected by PCR. Abnormal p53 protein accumulation was seen in 21 of the 43 carcinomas (49%), of which 18 were HPV negative. Twelve (57%) of the CM-1 positive cases were also positive for the mutation-specific antibody Pab 240. There was an obvious inverse relationship between the presence of papilloma viral DNA and abnormal p53 protein accumulation. CONCLUSIONS: p53 plays an important part in the development of lung carcinomas and, in some cases, HPV may contribute to it by binding and inactivating the p53 protein.  相似文献   
78.
79.

Aims

We investigated the expression of claudins 18 and 10 in a large set of primary lung carcinomas.

Methods and results

Immunohistochemical expression of claudin 18 was seen in 12.7 % and claudin 10 in 12.5 % of lung carcinomas. Their expression significantly associated with each other (p<0.001). The expression of claudin 18 and 10 was most prominent in lung adenocarcinomas which displayed positivity in 21.2% and 23.4 % of cases. Female patients had more often claudin 18 and 10 positive tumors, also separately in adenocarcinomas. Interestingly, claudin 10 (p=0.036) and claudin 18 (p=0.001) were more common in tumours of nonsmokers. In adenocarcinomas claudin 18 predicted a better survival (p=0.032). In Cox multivariate analysis, claudin 18 had an independent prognostic value (p=0.027).

Conclusion

The results show that both claudins are most commonly expressed in lung adenocarcinomas and they are more occasionally detected in other histological tumour types. Curiously, female patients and non-smokers express these claudins more commonly suggesting that they may play a part in the carcinogenesis of tobacco unrelated carcinoma. Claudin 18 associated with a better survival in lung adenocarcinoma and had an independent prognostic value and may thus be used in the evaluation of patient prognosis.  相似文献   
80.
Matriptase‐2 (TMPRSS6) has been identified as a breast cancer risk factor. Here, we examined relationships between TMPRSS6 genetic variations and breast cancer risk and survival, and determined the gene and protein expressions in breast tumors and assessed their clinical importance. Thirteen TMPRSS6 polymorphisms were genotyped in 462 invasive breast cancer cases and 458 controls. Gene expression was analyzed from 83 tumors and protein expression from 370 tumors. We then assessed the statistical significance of associations among genotypes, clinicopathological characteristics and survival. The TMPRSS6 variant rs2543519 was associated with breast cancer risk (p = 0.032). Multivariate analysis showed that four variants had effects on survival—rs2543519 (p = 0.017), rs2235324 (p = 0.038), rs14213212 (p = 0.044) and rs733655 (p = 0.021)—which were used to create a group variable that was associated with poorer prognosis correlating with more alleles related to reduced survival (p = 0.006; risk ratio, 2.375; 95% confidence interval, 1.287–4.382). Low gene expression was related to triple‐negative breast cancer (p = 0.0001), and lower protein expression was detected in undifferentiated (p = 0.019), large (p = 0.014) and ductal or lobular tumors (p = 0.036). These results confirm the association of TMRRSS6 variants with breast cancer risk and survival. Matriptase‐2 levels decrease with tumor progression, and lower gene expression is seen in poor‐prognosis‐related triple‐negative breast cancers. Our study is the first to show that matriptase‐2 gene variants are related to breast cancer prognosis, supporting matriptase‐2 involvement in tumor development.  相似文献   
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