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1.
Delayed contrast enhancement after injection of a gadolinium-chelate (Gd-chelate) is a reference imaging method to detect myocardial tissue changes. Its localization within the thickness of the myocardial wall allows differentiating various pathological processes such as myocardial infarction (MI), inflammatory myocarditis, and cardiomyopathies. The aim of the study was first to characterize benign myocarditis using quantitative delayed-enhancement imaging and then to investigate whether the measure of the extracellular volume fraction (ECV) can be used to discriminate between MI and myocarditis.In 6 patients with acute benign myocarditis (32.2 ± 13.8 year-old, subepicardial late gadolinium enhancement [LGE]) and 18 patients with MI (52.3 ± 10.9 year-old, subendocardial/transmural LGE), myocardial T1 was determined using the Modified Look-Locker Imaging (MOLLI) sequence at 3 Tesla before and after Gd-chelate injection. T1 values were compared in LGE and normal regions of the myocardium. The myocardial T1 values were normalized to the T1 of blood, and the ECV was calculated from T1 values of myocardium and blood pre- and post-Gd injection.In both myocarditis and MI, the T1 was lower in LGE regions than in normal regions of the left ventricle. T1 of LGE areas was significantly higher in myocarditis than in MI (446.8 ± 45.8 vs 360.5 ± 66.9 ms, P = 0.003) and ECV was lower in myocarditis than in MI (34.5 ± 3.3 vs 53.8 ± 13.0 %, P = 0.004).Both inflammatory process and chronic fibrosis induce LGE (subepicardial in myocarditis and subendocardial in MI). The present study demonstrates that the determination of T1 and ECV is able to differentiate the 2 histological patterns.Further investigation will indicate whether the severity of ECV changes might help refine the predictive risk of LGE in myocarditis.  相似文献   
2.
Autoimmune thyroid diseases (AITDs), which include Hashimoto thyroiditis (HT), Graves' disease (GD) and primary idiopathic myxoedema (PIM), are recognized as multifactorial diseases. In this study, we have examined single and haplotypic genetic variation across the major histocompatibility complex (MHC) in a Tunisian isolate with a high prevalence of AITDs (62 patients: 32 with GD, 9 with HT and 21 with PIM). Genotyping was performed for HLA class I and II alleles as well as polymorphisms within tumor necrosis factor (TNF), lymphotoxin alpha (TLalpha) and heat shock protein (HSP70-02 and HSP70-hom) genes. Our results showed association of HLA-A2-B50-TNF 2 haplotype with AITDs (p = 0.045). Linkage analysis using Simwalk2 program has shown significant result with TNF -308 gene polymorphism (p = 0.03). The FBAT has given evidence for genetic association with TNF -308 and HLA-DR gene polymorphisms. TNF 2 allele was associated with GD (p = 0.0011), whereas TNF 1, HLA-DR11 and DR12 (p = 0.0039, p = 0.00089 and p = 0.0056, respectively) were rather implicated in HT pathogenesis. Results found by TDT-STDT have confirmed the involvement of the TNF -308 gene polymorphism in AITD pathogenesis (p < 10(-9)).  相似文献   
3.
BackgroundIschemia-driven islet isolation procedure is one of the limiting causes of pancreatic islet transplantation. Ischemia-reperfusion process is associated with endothelium dysfunction and the release of pro-senescent microvesicles. We investigated whether pro-senescent endothelial microvesicles prompt islet senescence and dysfunction in vitro.Material and methodsPancreatic islets were isolated from male young rats. Replicative endothelial senescence was induced by serial passaging of primary porcine coronary artery endothelial cells, and microvesicles were isolated either from young passage 1 (P1) or senescent passage 3 (P3) endothelial cells. Islet viability was assessed by fluorescence microscopy, apoptosis by flow cytometry, and Western blot. Function was assessed by insulin secretion and islet senescence markers p53, p21, and p16 by Western blot. Microvesicles were stained by the PKH26 lipid fluorescent probe and their islet integration assessed by microscopy and flow cytometry.ResultsRegardless of the passage, half microvesicles were integrated in target islets after 24 hours incubation. Insulin secretion significantly decreased after treatment by senescent microvesicles (P3: 1.7 ± 0.2 vs untreated islet: 2.7 ± 0.2, P < .05) without altering the islet viability (89.47% ± 1.69 vs 93.15% ± 0.97) and with no significant apoptosis. Senescent microvesicles significantly doubled the expression of p53, p21, and p16 (P < .05), whereas young microvesicles had no significant effect.ConclusionPro-senescent endothelial microvesicles specifically accelerate the senescence of islets and alter their function. These data suggest that islet isolation contributes to endothelial driven islet senescence.  相似文献   
4.
Unconditional cash transfers (UCTs) are used as a humanitarian intervention to prevent acute malnutrition, despite a lack of evidence about their effectiveness. In Niger, UCT and supplementary feeding are given during the June–September “lean season,” although admissions of malnourished children to feeding programmes may rise from March/April. We hypothesised that earlier initiation of the UCT would reduce the prevalence of global acute malnutrition (GAM) in children 6–59 months old in beneficiary households and at population level. We conducted a 2‐armed cluster‐randomised controlled trial in which the poorest households received either the standard UCT (4 transfers between June and September) or a modified UCT (6 transfers from April); both providing 130,000 FCFA/£144 in total. Eligible individuals (pregnant and lactating women and children 6–<24 months old) in beneficiary households in both arms also received supplementary food between June and September. We collected data in March/April and October/November 2015. The modified UCT plus 4 months supplementary feeding did not reduce the prevalence of GAM compared with the standard UCT plus 4 months supplementary feeding (adjusted odds ratios 1.09 (95% CI [0.77, 1.55], p = 0.630) and 0.93 (95% CI [0.58, 1.49], p = 0.759) among beneficiaries and the population, respectively). More beneficiaries receiving the modified UCT plus supplementary feeding reported adequate food access in April and May (p < 0.001) but there was no difference in endline food security between arms. In both arms and samples, the baseline prevalence of GAM remained elevated at endline (p > 0.05), despite improved food security (p < 0.05), possibly driven by increased fever/malaria in children (p < 0.001). Nonfood related drivers of malnutrition, such as disease, may limit the effectiveness of UCTs plus supplementary feeding to prevent malnutrition in this context. Caution is required in applying the findings of this study to periods of severe food insecurity.  相似文献   
5.
The aim of this research study was to estimate anticardiolipin (IgG & IgM) antibodies (aCL) and lupus anticoagulant (LA) factor in patients of recurrent unexplained pregnancy loss and intrauterine fetal deaths (IUFD). 82 women were selected for this study by virtue of having more than two consecutive unexplained pregnancy losses in their first trimester and were referred by the department of Obstetrics and Gynecology, King Saud Medical City Hospital, Riyadh, KSA. All patients had gone through a standardized investigation sequence. Lupus anticoagulants and Anticardiolipin antibodies (IgM and IgG) were detected in the serum by the enzyme linked immunosorbent assay method. To check the significance of aCL and LA, two-tailed t-test was done. Non parametric data was calculated either by Chi-Square test or Fischer exact test when relevant. Total 82 females grouped as 52 cases of recurrent (≥ 2) mainly first and second trimester miscarriage and 30 cases of recurrent (≥ 2) late intrauterine fetal death. Lupus anticoagulants was observed in twenty one (21) cases (25.6%) while anticardiolipin antibodies IgM and or IgG positive cases were estimated in forty four (44) cases (53.65%). The prevalence of APS in both studied group was thirty five (35) cases (42.68%). Antiphospholipid antibodies are calculated as the most important reason for recurrent abortion. The patients with unexplained recurrent pregnancy loss must be advised to go for a screening test for all this aPL antibodies.  相似文献   
6.
The objective of the study was to determine the degree of linear growth retardation of patients with vitamin D deficiency rickets at presentation and the magnitude of catch-up growth in relation to their calcium (Ca) homeostasis and hormones affecting it before and after treatment. This prospective study recorded the anthropometric data and measured the circulating 25-hydroxy vitamin D (25-OH-D), insulin-like growth factor I (IGF-I), parathyroid hormone, Ca, phosphate, and alkaline phosphatase concentrations in 46 infants and children with nutritional (vitamin D deficiency) rickets before and 6 months or more after treatment with one intramuscular injection of vitamin D3 megadose (300000 IU). Forty normal age- and sex-matched children were included as controls for the auxological data. At presentation, patients' mean age = 13.1 +/- 1.1 months, length standard deviation scores (LSDS) = -1.5 +/- 0.2, and body mass index = 16.3 +/- 0.85. They were significantly shorter and had markedly lower growth velocity standard deviation scores (GVSDS) compared with normal controls (LSDS = 0.25 +/- 0.18 and 0.31 +/- 0.22, respectively). Six months after treatment, the LSDS increased significantly in patients to -0.45 +/- 0.13, with a significantly increased GVSDS (2.76 +/- 0.45) and body mass index (16.9 +/- 0.65). They were still shorter but with significantly higher GVSDS compared with normal controls. Serum Ca and phosphate concentrations increased from 2.07 +/- 0.25 and 1.23 +/- 0.24 mmol/L, respectively, before treatment to 2.44 +/- 0.2 and 1.94 +/- 0.2 mmol/L, respectively, after treatment. Serum alkaline phosphatase and parathyroid hormone concentrations decreased from 1183 +/- 219 U/L and 294 +/- 87 pg/mL, respectively, before treatment to 334 +/- 75 U/L and 35.2 +/- 15.2 pg/mL, respectively, after treatment. The 25-OH-D level increased from 4.5 +/- 0.56 ng/mL before treatment to 44.5 +/- 3.7 ng/mL after treatment. Circulating concentrations of IGF-I increased significantly after treatment (52.2 +/- 18.9 ng/mL) vs before treatment (26.6 +/- 12.8 ng/mL). The 25-OH-D concentrations were correlated significantly with the IGF-I levels before and after treatment (r = 0.603 and r = 0.59, respectively; P < .001). The GVSDS after treatment was correlated with the increase of IGF-I and 25-OH-D levels (r = 0.325 and r= 0.314, respectively; P < .01). These data denote that the accelerated linear growth after treatment of nutritional vitamin D deficiency is mediated through activation of the growth hormone/IGF-I system and suggests an important role of vitamin D as a link between the proliferating cartilage cells of the growth plate and growth hormone/IGF-I secretion. Three different sequential stages of vitamin D deficiency can be recognized according to the clinical/radiological, biochemical, and hormonal data of patients at presentation.  相似文献   
7.
Objectives:To explore the changing patterns of long-stay patients (LSP) to improve the utilization of pediatric intensive care units (PICUs) resources.Methods:This is a 2-points cross-sectional study (5 years apart; 2014-2019) conducted among PICUs and SCICUs in Riyadh, Saudi Arabia. Children who have stayed in PICU for more than 21 days were included.Results:Out of the 11 units approached, 10 (90%) agreed to participate. The prevalence of LSP in all these hospitals decreased from 32% (48/150) in 2014 to 23.4% (35/149) in 2019. The length of stay ranged from 22 days to 13.5 years. The majority of LSP had a neuromuscular or cardiac disease and were admitted with respiratory compromise. Ventilator-associated pneumonia was the most prevalent complication (37.5%). The most commonly used resources were mechanical ventilation (93.8%), antibiotics (60.4%), and blood-products transfusions (35.4%). The most common reason for the extended stay was medical reasons (51.1%), followed by a lack of family resources (26.5%) or lack of referral to long-term care facilities (22.4%).Conclusion:A long-stay is associated with significant critical care bed occupancy, complications, and utilization of resources that could be otherwise utilized as surge capacity for critical care services. Decreasing occupancy in this multicenter study deserves further engagement of the healthcare leaders and families to maximize the utilization of resources.  相似文献   
8.
Para‐aortic lymph node (PALN) recurrence is often seen in patients with lower thoracic esophageal cancer treated by esophagectomy with extended lymph node dissection. However, the clinicopathological characteristics of patients with PALN metastasis and the significance of PALN dissection are unknown. A total of 283 patients with lower thoracic esophageal cancer underwent esophagectomy with lymphadenectomy at our hospital between April 1984 and March 2007. Among these 283 patients, 60 patients were enrolled in this retrospective study according to following criteria: (i) clinical T2 to T4 tumor, (ii) no clinical PALN metastasis, and (iii) received PALN dissection. PALN dissection was indicated by a tumor depth of at least T2 and no severe complications. The clinicopathological data, recurrence pattern, and overall survival were compared between patients with PALN and without PALN metastasis. The mean length of surgery was 587 min and the mean blood loss was 1383 mL. The morbidity was 33.3% and mortality was 5% in this series. Sixteen patients (26.7%) had PALN metastasis; these showed significantly more lymph node metastases (15.8 ± 13.2 vs. 3.0 ± 3.2, P < 0.0001) and significantly worse survival rates (53.3% vs. 79.9% at 1 year, 6.7% vs. 62.0% at 3 years, P < 0.0001) than patients without PALN metastasis. The incidence of lymph node recurrence (P < 0.0001) and hematogenous recurrence (P= 0.0487) was also higher in patients with PALN metastasis than in patients without PALN metastasis. Among the 16 patients with PALN metastasis, a univariate analysis revealed total number of metastatic nodes < 8 (P= 0.0325) to be a significant prognostic factor. A multivariate logistic regression analysis of the regional lymph nodes identified the invasion of the lower mediastinal nodes (hazard ratio = 6.120) and retroperitoneal nodes (hazard ratio = 15.167) to be significantly correlated with PALN metastasis. PALN metastasis is suggested to be related to the systemic spread of lymphatic metastasis even in lower thoracic esophageal cancer. PALN dissection for pathological PALN(+) patients should not be performed. It remains to be determined in future prospective studies whether patients without pathological PALN metastasis, but showing PALN micrometastasis, could achieve improved survival with PALN dissection.  相似文献   
9.
10.

Background

Neoadjuvant chemotherapy (NACT) improves the prognosis of patients with esophageal cancer who respond, but it is not effective in nonresponders. Therefore, it is crucial to establish a reliable method of predicting response before initiation of chemotherapy. Hypercoagulability, which is thought to be because of upregulation of tissue factor (TF) in cancer cells, was reported to be associated with chemoresistance. The aim of this study was to investigate the association between TF expression and response to NACT in esophageal cancer.

Methods

In 67 patients with advanced esophageal cancer, TF expression in pretreatment biopsy samples was evaluated immunohistochemically and correlated with clinicopathologic factors and response to chemotherapy.

Results

TF was expressed by 43.3% of the tumors, but there were no correlations observed with any clinicopathologic parameters examined. Clinical and histologic responses to chemotherapy were significantly worse in TF-positive patients compared with TF-negative patients. Multivariate analysis revealed that TF expression was significantly associated with a poor clinical response (P = 0.0431). TF expression was also independently associated with poor progression-free survival (P = 0.0353).

Conclusions

TF expression levels in pretreatment biopsy samples are useful for predicting response to NACT in advanced esophageal cancer. Further studies of mechanisms underlying the relationship between TF expression and chemosensitivity are needed.  相似文献   
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