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Methylation of tumor suppressor genes has been implicated in breast cancer development. However, methylation profiles of different breast lesions, subtypes of carcinoma in particular, have not been examined in detail. In this study, we use methylation-specific PCR (MSP) to generate gene methylation profiles of different breast lesions and to test the clinical utility of such profiles. We examined the methylation status of three genes, RARbeta2, RASSF1A, and cyclin D2, on 102 samples of breast tissue, from benign (n = 36), to in situ carcinoma (n = 21), to invasive carcinoma (n = 45). We found that almost all cases of invasive carcinoma (96%) contained at least one methylated gene from our panel, whereas gene methylation was less common among benign lesions (42%) and in situ carcinoma (76%). Of the three genes, cyclin D2 methylation was most specific for malignancy because only 1 of 35 benign cases was methylated at this gene (1 case was not informative). The major histologic subtypes of invasive carcinoma show similar methylation profiles in the genes examined. We next performed MSP analysis on archival breast fine-needle aspiration (FNA) biopsy samples and corresponding surgical biopsy specimens and found a high concordance between the two types of specimens. We then analyzed 17 breast FNA biopsy samples with an indeterminate diagnosis. In this setting, MSP had a high specificity (100%) and modest sensitivity (67%) for identifying malignancy.  相似文献   
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Wood dust is an irritant and is carcinogenic to the nasal mucosa. It inhibits its own clearance from the nose. It therefore makes sense to lavage retained wood dust from the nose following exposure. To our knowledge this is the second study conducted to determine whether the procedure of nasal lavage reduces nasal symptoms in woodworkers. Forty-six woodworkers from 150 approached volunteered to trial nasal lavage using gravity fed, home-made unbuffered isotonic saline for 2 months in a crossover trial and then be followed-up a year later. The group reported significantly decreased nasal symptoms and over half continued to use nasal lavage voluntarily after 1 year. Results support the findings of the previous study that nasal lavage improves nasal symptoms and supplements those findings with data indicating patterns of voluntary usage following the study's conclusion. It is concluded that nasal lavage is an acceptable, effective and inexpensive option with minimal side effects for woodworkers who experience nasal symptoms and who wish to try the procedure.  相似文献   
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Immune responses directed at glycosylphosphatidylinositol (GPI) anchors of Plasmodium falciparum may offer protection against symptomatic malaria. To independently explore the effect of age on generation of the anti-GPI IgG response, we measured serum anti-GPI IgGs in a longitudinal cohort of migrant Javanese children (6-12 years old) and adults (> or = 20 years old) with equivalent numbers of exposures to P. falciparum in Papua, Indonesia. While the peak response in adults was achieved after a single infection, comparable responses in children required > or = 3-4 infections. Significantly fewer children (16%) than adults (41%) showed a high (optical density > 0.44) anti-GPI IgG response (odds ratio [OR] = 3.8, 95% confidence interval [CI] = 2.3-6.3, P < 0.0001), and adults were more likely to show a persistently high response (OR = 5.5, 95% CI = 1.0-56.8, P = 0.03). However, the minority of children showing a strong response were significantly less likely to experience symptoms with subsequent parasitemia compared with those with a weak response (OR = 4.0, 95% CI = 1.1-13.8, P = 0.02). This effect was not seen among high- and low-responding adults (OR = 1.2, 95% CI = 0.5-2.8, P = 0.60). Host age, independent of cumulative exposure, apparently represents a key determinant of the quantitative and qualitative nature of the IgG response to P. falciparum GPI.  相似文献   
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When severely immunodeficient HIV/HCV co-infected patients are treated with antiretroviral therapy, it is important to know whether HCV-specific antibody responses recover and whether antibody profiles predict the occurrence of HCV-associated immune restoration disease (IRD). In 50 HIV/HCV co-infected patients, we found that antibody reactivity and titres of neutralising antibodies (nAb) to JFH-1 (HCV genotype 2a virus) increased over 48 weeks of therapy. Development of HCV IRD was associated with elevated reactivity to JFH-1 before and during the first 12 weeks of therapy. Individual analyses of HCV IRD and non-HCV IRD patients revealed a lack of an association between nAb responses and HCV viral loads. These results showed that increased HCV-specific antibody levels during therapy were associated with CD4+ T-cell recovery. Whilst genotype cross-reactive antibody responses may identify co-infected patients at risk of developing HCV IRD, neutralising antibodies to JFH-1 were not involved in suppression of HCV replication during therapy.  相似文献   
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Parainfluenza virus type 3(PIV‐3) commonly causes respiratory tract infections in hematopoietic stem cell transplant (HSCT) patients. The majority of PIV‐3 infections develop in patients who have undergone stem cell transplantation from unrelated donors. From these patients, bronchoalveolar lavage (BAL) fluid and/or lung biopsies are often collected and sent for evaluation of infectious processes. However, cytologic findings associated with a PIV‐3 infection in BAL fluid have not been reported in the literature. We describe BAL cytology and lung biopsy findings in a patient who received an HSCT from a related donor and subsequently developed a PIV‐3 infection. This patient was noted to have scattered reticular‐nodular opacities in both lungs on computed tomogram scan and underwent transbronchial biopsy and BAL of the left lower lobe. Examination of the BAL fluid revealed scattered multinucleated giant cells intermixed with inflammatory cells. The lung biopsy showed organizing pneumonia associated with several multinucleated respiratory epithelial cells containing rare intracytoplasmic inclusions. Gram, periodic acid Schiff, Gomori methenamine silver, and acid fast stains on the biopsy specimen failed to reveal microorganisms. A sample of the BAL fluid sent for respiratory viral culture grew PIV‐3. These findings suggest that the presence of giant cells in transplant patients with organizing pneumonia should raise suspicion of a PIV‐3 infection. Diagn. Cytopathol. 2014;42:521–524. © 2013 Wiley Periodicals, Inc.  相似文献   
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Distant metastasis is responsible for the death of nearly 45,000 women per year in the US alone. At present, we have no clear understanding about the genetic events that govern the ability of breast cancer cells to settle at and colonize in specific sites in the body. This information is critical for developing therapeutic strategies that would target the tumor cells and their supporting environment at distant sites. This review will discuss investigations on 1) the steps of the metastatic pathway, 2) innovative technologies such as radiologic imaging and molecular manipulations of cells that would help us to study metastasis in real time, 3) strengths and weaknesses of current models for studying metastasis, and 4) how best to design large comprehensive gene searches during metastatic progression of breast cancer. These advances will enable the development of therapies targeted towards blocking the outgrowth of metastatic cells.  相似文献   
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Noradrenaline (NA) was conjugated to different protein carriers witglutaraldehyde. During the catecholamine conjugate synthesis, precautions were taken in order to preserve the structure of NA. Anti-NA antibodies were raised in rabbits and tested using a modified enzyme-linked immunosorbent assay and immunocytochemistry. The most immunoreactive antigen was found to be the reduced NA conjugate. The octopamine conjugate was recognized by the NA antiserum 16x less than the reduced NA conjugate. The other conjugates, dopamine,l-dihydroxyphenylalanine and adrenaline were poorly recognized by the anti-NA antibodies. A good correlation was found between results obtained using the in vitro enzyme-linked immunosorbent assay and immunocytochemistry.  相似文献   
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