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BACKGROUND: Low dietary intake and low serum concentrations of vitamin B6 and/or folate are associated with increased risk of vascular events, possibly because of their association with inflammation, which plays a crucial role in the pathogenesis of cardiovascular diseases. METHODS: Using data from 1320 participants in the population-based InCHIANTI study (586 men and 734 women; median age, 69 years; range, 21-102 years) for whom complete data on folate, vitamin B6, inflammatory markers, 5,10-methylenetetrahydrofolate reductase (MTHFR) C677T sequence variant, and important covariates were available, we evaluated the association of inflammatory markers with circulating concentrations of vitamin B6 and folate, independently of dietary vitamin intake, circulating vitamin concentrations, and MTHFR C677T sequence variant. RESULTS: According to multiple linear regression analysis, C-reactive protein and interleukin-6 receptor were strongly and negatively associated with circulating vitamin B6 but not with folate concentrations, independent of age, sex, serum creatinine, serum albumin, total energy intake, smoking history, dietary nutrient intake, and circulating homocysteine and vitamin concentrations. Serum folate concentrations were related to MTHFR 677 TT genotype in persons with folate intake in the lowest tertile (< 221.2 microg/day). Vitamin C and retinol intakes were strongly and positively associated with serum folate concentrations independent of age, sex, serum creatinine, serum albumin, total energy intake, smoking history, homocysteine plasma concentrations, dietary nutrient intakes, serum vitamin B6 and vitamin B12 concentrations, and MTHFR C677T sequence variant. CONCLUSIONS: Low serum vitamin B6, but not serum folate, concentrations are independent correlates of the proinflammatory state, and both are influenced by antioxidant reserves.  相似文献   
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In spite of their presumed relevance in maintaining interalveolar septal fluid homeostasis, the knowledge of the anatomy of human lung lymphatics is still incomplete. The recent discovery of reliable markers specific for lymphatic endothelium has led to the observation that, contrary to previous assumptions, human lymphatic vessels extend deep inside the pulmonary lobule in association with bronchioles, intralobular arterioles or small pulmonary veins. The aim of this study was to provide a morphometric characterization of lymphatic vessels in the periphery of the human lung. Human lung sections were immunolabelled with the lymphatic marker D2-40, followed by blood vessel staining with von Willebrand Factor. Lymphatic vessels were classified into: intralobular (including those associated with bronchovascular bundles, perivascular, peribronchiolar and interalveolar), pleural (in the connective tissue of the visceral pleura), and interlobular (in interlobular septa). The percentage area occupied by the lymphatic lumen was much greater in the interlobular septa and in the subpleural space than in the lobule. Most of the intralobular lymphatic vessels were in close contact with a blood vessel, either alone or within a bronchovascular bundle, whereas 7% were associated with a bronchiole and < 1% were not connected to blood vessels or bronchioles (interalveolar). Intralobular lymphatic size progressively decreased from bronchovascular through to peribronchiolar, perivascular and interalveolar lymphatics. Lymphatics associated with bronchovascular bundles had similar morphometric characteristics to pleural and interlobular lymphatics. Shape factors were similar across lymphatic populations, except that peribronchiolar lymphatics had a marginally increased roundness and circularity, suggesting a more regular shape due to increased filling, and interlobular lymphatics had greater elongation, due to a greater proportion of conducting lymphatics cut longitudinally. Unsupervised cluster analysis confirmed a marked heterogeneity of lymphatic vessels both within and between groups, with a cluster of smaller vessels specifically represented in perivascular and interalveolar lymphatics within the alveolar interstitium. Our data indicate that intralobular lymphatics are a heterogeneous population, including vessels surrounding the bronchovascular bundle analogous to the conducting vessels present in the pleural and interlobular septa, many small perivascular lymphatics responsible for maintaining fluid balance in the alveolar interstitium, and a minority of intermediate lymphatics draining the peripheral airways. These lymphatic populations could be differentially involved in the pathogenesis of diseases preferentially involving distinct lung compartments.  相似文献   
34.
Bergantini  L  Cameli  P  d’Alessandro  M  Vagaggini  C  Refini  RM  Landi  C  Pieroni  MG  Spalletti  M  Sestini  P  Bargagli  E 《Clinical and experimental medicine》2019,19(4):487-494
Clinical and Experimental Medicine - Background The pathogenetic and regulatory roles of natural killer (NK) and natural killer T-like cells in interstitial lung diseases (ILDs), fibrotic and...  相似文献   
35.
Cross-sectional studies have reported associations between a number of polymorphisms in the estrogen receptor alpha (ERα) gene and the body mass index, hypertension, coronary flow reserve, coronary atherosclerosis, and osteoporosis. There are currently no data examining the genetic polymorphisms of the ERα and estrogen receptor beta (ERβ) genes in melanoma patients. The aims of this study were to investigate the associations of genetic polymorphisms of the ERα and ERβ genes with melanoma risk. The study group consisted of consecutive patients who visited the Department of Dermatology of the University of Florence between March 2005 and July 2007 for surgical excision of melanoma. In our study, homozygosity for the wild-type alleles showed different results at the PvuII, XbaI, and AluI restriction sites. Only the AluI site showed a lower proportion of the A allele in the melanoma group compared to the control group; the P and X alleles were lower in the control group than in the melanoma group. The distribution of wild-type alleles is important because these alleles have a protective role in the expression of altered proteins, which involves the ERs in our case. Because of the phenotypic prevalence of the wild-type allele, the heterozygotes did not express the polymorphism. The homozygosity of the polymorphic-type alleles shows that a alleles are more frequent in the case group than in the control group, with proportions of 43.8 and 39.5%, respectively. These results suggest that a polymorphism at the AluIrestriction site correlates with a higher proportion of melanoma. Thus, the polymorphism of ERβ could ascribe to a higher susceptibility to melanoma.  相似文献   
36.
Leiomyosarcomas are rare malignant tumors of smooth muscles. Superficial leiomyosarcoma is generally a disease of middle age, most frequently encountered between 40 and 60 years of age. It is usually diagnosed late or misdiagnosed, since it is a very rare tumor of the head and neck. Awareness of the particularly misleading features of this tumor, especially in elderly patients, is important, as delayed diagnosis is correlated with larger size and invasiveness into contiguous structures, which influence the practicability of radical resection. We present the case of an 81-year-old man with cutaneous leiomyosarcoma on the forehead.  相似文献   
37.
The association of contiguous or 'collision' tumours in the same biopsy specimen is not uncommon and is often reported in the literature. The most common association, basal cell carcinoma (BCC) and naevus, is very difficult to diagnose clinically. We describe a 38-year-old woman with a previous history of melanoma, who presented with a modified pigmented lesion of the hip that had begun to change 6 months earlier. Histologically, the lesion was a melanocytic compound naevus and a BCC with a seborrhoeic keratosis. The case was investigated clinically and by focusing on the dermoscopic features and their pathological correlates. Cutaneous collision tumours are extremely difficult to diagnose preoperatively, even with the help of dermoscopy, in particular when one of the lesions is melanocytic.  相似文献   
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Sarcoidosis is a heterogeneous granulomatous disease. Biological markers and clinical features could allow specific phenotypes to be associated with different prognosis, severity and treatment responses. This retrospective multicentre study aims to analyse the clinical and immunological features of sarcoidosis and to identify a routine non-invasive biomarker useful in clinical practice.Materials and methods:129 Caucasian patients with sarcoidosis (median age IQR, 56 (47-62)) were enrolled retrospectively in the study. Medical history, routine laboratory findings, lung function results and radiological features from the last examination of October 2019 – February 2020 were gathered from the patients’ clinical records.Results:Regardless their clinical status at disease onset, at the last clinical examination we didn’t observe any differences in terms of therapeutic management between symptomatic and asymptomatic patients. Stratifying sarcoidosis population according to therapeutic management, the N/L ratio was higher in the treated group than in the non-treated group (p=0.0034). Receiver operating curve (ROC) analysis distinguished these two groups according to N/L ratio with an area under the curve (AUC) of 65.3% and a best cut-off value of 2.21. Peripheral N/L ratio was significantly higher in radiological stages 2-4 than in stages 0-1 (p=0.0090) distinguishing these two groups with an AUC of 64% and a best cut-off value of 2.13.Discussion:In our multicentric cohort study similar periodic follow-up can be suggested for symptomatic and asymptomatic sarcoidosis patients at onset. In the heterogeneous context of this disease, N/L ratio proved to be a useful and simple routine laboratory biomarker related to disease activity and need for treatment.  相似文献   
40.
High-resolution melting analysis (HRMA) provides a valid approach to efficiently detect DNA genetic and somatic mutations. In this study, HRMA was used for the screening of 116 colorectal cancers (CRCs) to detect hot-spot mutations in the KRAS and BRAF oncogenes. Mutational hot spots on the PIK3CA gene, exons 9 and 20, were also screened. Direct sequencing was used to confirm and characterize HRMA results. HRMA revealed abnormal melting profiles in 65 CRCs (56.0%), 16 of them harboring mutations in 2 different genes simultaneously. The frequency of mutations was 17.2% for PIK3CA (11.2% in exon 9 and 6.0% in exon 20), 43.1% for KRAS exon 2, and 9.5% in exon 15 of the BRAF gene. We found a significant association between PIK3CA and KRAS mutations (P = .008), whereas KRAS and BRAF mutations were mutually exclusive (P = .001). This report describes a novel approach for the detection of PIK3CA somatic mutations by HRMA.  相似文献   
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