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991.
The matrix-inserted surface transplantation model is an in vivo assay used to analyse the kinetics of tumor-vessel interactions during different stages of skin carcinoma progression. This system allows the study of host-tumor interface, i.e. penetration of tumor cells into normal host tissue as well as infiltration of normal host cells into the tumor. In the present study, image analysis algorithms for processing and quantifying the extent of such migratory and tissue remodeling events are presented. The proposed method is non-parametric and its originality lies in its particularity to take into account the specific geometry of tumor-host interface. This methodology is validated by evaluating the contribution of matrix metalloproteases (MMPs) in skin carcinoma invasion and vascularization through pharmacological and genetic approaches.  相似文献   
992.
STUDY OBJECTIVE: To determine the predictive factors of morbidity and mortality in patients with end-stage respiratory disease. DESIGN: Prospective, multicenter cohort study. SETTING: Thirteen outpatient chest clinics within the Association Nationale de Traitement à Domicile de l'Insuffisance Respiratoire. PARTICIPANTS: Stable adult patients with chronic respiratory failure receiving long-term oxygen therapy and/or home mechanical ventilation (n = 446; 182 women and 264 men; aged 68.5 +/- 12.1 years [+/- SD]); Respiratory diseases were COPD in 42.8%, restrictive disorders in 36.3%, mixed respiratory failure in 13.5%, and bronchiectasis in 7.4%. Recruitment was performed during the yearly examination. Patients with neuromuscular diseases and sleeping apnea were excluded. MEASUREMENTS AND RESULTS: Hospitalization days and survival were recorded during a follow-up of 14.3 +/- 5.6 months. Body mass index (BMI), serum albumin, and transthyretin levels were considered for their predictive value of outcome, together with demographic data, underlying respiratory disease, respiratory function, hemoglobin, C-reactive protein, smoking habits, oral corticosteroid use, and antibiotic treatment courses. Overall, 1.8 +/- 1.7 hospitalizations (cumulative stay, 17.6 +/- 27.1 days) were observed in 254 of 446 patients (57%). Independent predictors of hospitalization were oral corticosteroids, FEV(1), and plasma C-reactive protein. One-year and 2-year cumulative survivals were 93% and 69%, respectively. Plasma C-reactive protein, BMI, Pao(2) on room air, and oral corticosteroids independently predicted survival in multivariate analysis. CONCLUSION: Besides established prognosis factors such as FEV(1) and Pao(2), nutritional depletion as assessed by BMI and overall systemic inflammation as estimated by C-reactive protein appear as major determinants of hospitalization and death risks whatever the end-stage respiratory disease. BMI and C-reactive protein should be included in the monitoring of chronic respiratory failure. Oral corticosteroids as maintenance treatment in patients with end-stage respiratory disease are an independent risk factor of death, and should be avoided in most cases.  相似文献   
993.
原发性胆汁性肝硬化外周血T细胞亚群及细胞因子的检测   总被引:9,自引:2,他引:9  
目的 探讨中国人原发性胆汁性肝硬化患者的T细胞亚群及细胞因子存在状况及意义。方法 选未经特殊治疗的原发性胆汁性肝硬化 (PBC) 2 5例 ,性别、年龄匹配的健康人 2 0例作为对照组。以双抗体夹心ELISA法检测外周血细胞因子IL_2、IFN_γ、IL_4、IL_10、TNF_α水平。以S_P法检测外周血T淋巴细胞亚群。结果 与对照组比较 ,PBC患者CD+ 4 T细胞升高 ,CD+ 8T细胞下降 ,CD+ 4 /CD+ 8比值上升 (P <0 0 1)。PBC组IL_2、IFN_γ、TNF_α明显升高 (P <0 0 1) ,IL_10轻度上升 (P <0 0 5 ) ,IL_4水平与对照组比较无差异 (P >0 0 5 )。结论 PBC外周血CD+ 4 T细胞和Th1细胞因子占优势 ,提示其在PBC发病机制中发挥重要作  相似文献   
994.
995.
OBJECTIVE: To analyze the pattern of osteoarticular lesions in patients with sarcoidosis hospitalized in 4 rheumatology departments. METHODS: We carried out a systematic retrospective analysis of cases with sarcoidosis admitted in the last 10 years, using hospital databases. Two distinct groups were defined from the outset: patients with L?fgren's syndrome (LS) or sarcoid rheumatism (SR). We assessed the following items: distribution of arthritis, chronicity, systemic manifestations, biochemical and immunological measures. RESULTS: We included 100 patients (75% women); 43% had LS and 57% SR. Osteoarticular symptoms revealed the disease in 85% of patients. The patients in the LS group were younger than those in the SR group (41 +/- 9 vs 48 +/- 13 yrs; p < 0.006) and were more likely to have oligoarthritis involving ankles (58% vs 32%; p = 0.04) and high C-reactive protein concentrations (63% vs 33%; p < 0.005). Patients with SR presented osteoarticular symptoms in the form of oligoarthritis (32%), polyarthritis (32%), bony erosion in 8/57 (14%), and osteitis in 9/57 (16%). Lung interstitial involvement was more frequent in the SR group than in the LS group (38% vs 18%; p = 0.03). Chronic polyarthritis was associated with the detection of rheumatoid factor (p = 0.004). Osteitis occurred in older patients (p = 0.02). CONCLUSION: SR was the most frequent manifestation leading to hospitalization; it was characterized by oligoarthritis and polyarthritis and associated with interstitial lung involvement. Osseous involvement occurred in a quarter of SR patients with similar frequency of erosions targeting the distal small bones and osteitis. These latter occurred at a later age.  相似文献   
996.
AIMS: To evaluate the innocuousness of intense and prolonged exercise training above the threshold for myocardial ischaemia (1 mm ST-segment depression). METHODS AND RESULTS: Twenty-two patients with ischaemic heart disease (IHD) were randomized to exercise training either at a target intensity that induced myocardial ischaemia (ischaemic group) or that adhered to current guidelines (control group). Training was progressively increased to 60 min under continuous electrocardiographic (ECG) monitoring. Cardiac troponin T (cTnT) was measured at various intervals. Ambulatory ECG monitoring was performed before and after 6 weeks of training and left ventricular function was evaluated in the ischaemic group after at least 6 weeks of training. The ischaemic group had myocardial ischaemia during the first 20, 40, and 60 min exercise sessions for 12.3 +/- 6.8, 29.0 +/- 12.9, and 49.8 +/- 2.2 min, respectively, with ST-segment depression ranging from 1.0 to 2.1 mm. No patient in either group demonstrated significant arrhythmias or increased cTnT. The ischaemic group had preserved left ventricular function. CONCLUSION: In patients with IHD, prolonged and repeated ischaemic training sessions up to 60 min can be well tolerated without evidence of myocardial injury, significant arrhythmias, or left ventricular dysfunction.  相似文献   
997.
目的 分析白大衣高血压(WCH)患者动态脉压(APP)及动态脉压指数(APPI)的特征,探讨WCH对血管硬化的影响.方法 WCH患者60例、高血压I级患者60例(高血压组)和血压正常者50名(对照组)入选本研究,测量其诊室血压和动态血压,对各组APP及APPI进行组间比较.结果 WCH组和高血压组患者的诊室脉压及脉压指数高于对照组(P<0.01),且WCH组高于高血压组(P<0.01);高血压组患者24 h APP大于WCH组和对照组(P<0.01),WCH组患者的白天动态脉压(dAPP)大于对照组(P<0.01),高血压组患者24 h APPI、白天APPI(dAPPI)和夜间APPI(nAPPI)均大于WCH组和对照组(P<0.01),WCH组24 h APPI、dAPPI和nAPPI亦均大于对照组(P<0.05).结论 WCH不同于正常人群,会对血管造成一定程度的损伤,引起血管硬化,但其危害程度小于高血压,造成的损伤作用白天更明显.  相似文献   
998.
999.
Our objective was the clinical validation of an automated algorithm based on surface electromyography (EMG) for differentiation between convulsive epileptic and psychogenic nonepileptic seizures (PNESs). Forty‐four consecutive episodes with convulsive events were automatically analyzed with the algorithm: 25 generalized tonic–clonic seizures (GTCSs) from 11 patients, and 19 episodes of convulsive PNES from 13 patients. The gold standard was the interpretation of the video‐electroencephalographic recordings by experts blinded to the EMG results. The algorithm correctly classified 24 GTCSs (96%) and 18 PNESs (95%). The overall diagnostic accuracy was 95%. This algorithm is useful for distinguishing between epileptic and psychogenic convulsive seizures. Ann Neurol 2015;77:348–351.  相似文献   
1000.

BACKGROUND

Increasing the attractiveness of primary care careers is a key step in addressing the growing shortage of primary care physicians. The purpose of this review was to (1) identify interventions aimed at increasing the proportion of undergraduate medical students choosing a primary care specialty, (2) describe the characteristics of these interventions, (3) assess the quality of the studies, and (4) compare the findings to those of a previous literature review within a global context.

METHODS

We searched MEDLINE, EMBASE, ERIC, CINAHL, PsycINFO, The Cochrane Library, and Dissertations & Theses A&I for articles published between 1993 and February 20, 2015. We included quantitative and qualitative studies reporting on primary care specialty choice outcomes of interventions in the undergraduate medical curriculum, without geographic restrictions. Data extracted included study characteristics, intervention details, and relevant outcomes. Studies were assessed for quality and strength of findings using a five-point scale.

RESULTS

The review included 72 articles reporting on 66 different interventions. Longitudinal programs were the only intervention consistently associated with an increased proportion of students choosing primary care. Successful interventions were characterized by diverse teaching formats, student selection, and good-quality teaching. Study quality had not improved since recommendations were published in 1995. Many studies used cross-sectional designs and non-validated surveys, did not include control groups, and were not based on a theory or conceptual framework.

DISCUSSION

Our review supports the value of longitudinal, multifaceted, primary care programs to increase the proportion of students choosing primary care specialties. Isolated modules or clerkships did not appear to be effective. Our results are in line with the conclusions from previous reviews and add an international perspective, but the evidence is limited by the overall low methodological quality of the included studies. Future research should use more rigorous evaluation methods and include long-term outcomes.

Electronic supplementary material

The online version of this article (doi:10.1007/s11606-015-3372-9) contains supplementary material, which is available to authorized users.KEY WORDS: Medical education-undergraduate, Primary care, Systematic reviews, Workforce  相似文献   
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