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991.
992.
Urine samples with trimethoprim-resistant or trimethoprim-sensitive Gram-negative bacteria and samples with no bacterial growth (NG) were identified. Age-sex matched community controls were generated with each trimethoprim-resistant case. These four groups were evaluated for exposure. Prior trimethoprim use was significantly more common in the trimethoprim-resistant group when compared with the trimethoprim-sensitive or the NG group. Prior hospitalization was significantly less common in the trimethoprim-resistant than the trimethoprim-sensitive group, but not with the NG group. Prior oestrogen exposure was associated with trimethoprim resistance. There were no associations found for diabetes or prior corticosteroid exposure. Community controls were found to be inappropriate controls for the study of trimethoprim-resistant bacteria in urine samples.  相似文献   
993.
BACKGROUND: Modern linear accelerators permit the use of irregular fields due to their flexible collimator systems with separately movable jaws or multileaf collimators. When using such irregular fields in the clinical practice output factors have to be corrected for enhanced backscatter to the dose monitor as compared with the conventional block shieldings. METHODS: A method is presented to detect the monitor backscatter contributions to the output factor for irregular field settings. RESULTS: The monitor backscatter factors have been measured using a telescopic device for 2 different treatment head geometries (Varian Clinac 2100C/D, General Electric Saturne 15) and for 3 photon radiation qualities (nominal energies X6, X18, X12). A method is introduced to calculate the monitor backscatter for arbitrary irregular treatment fields from the experimental data for square or rectangular fields. CONCLUSIONS: Besides the corrections for changes in phantom scatter and changes in the aperture, corrections for monitor backscatter have to be taken into account in many clinical cases. They can contribute up to more than 10% compared with the monitor values for free regular fields.  相似文献   
994.
BackgroundThis study aims to quantitatively and qualitatively assess microvascular complications and their risk factors in patients with cystic fibrosis-related diabetes (CFRD) compared to those with type 1 diabetes mellitus (DM1).Methods79 patients with CFRD were matched with 79 patients with DM1 according to sex, age and duration of insulin therapy. Retinopathy, peripheral neuropathy, nephropathy and microalbuminuria were the microvascular complications assessed. Risk factors studied were: smoking, BMI, HbA1c, cholesterol, cholesterol/HDL ratio, diastolic and systolic blood pressure.ResultsBoth groups had the same number of microvascular complications (29%). CFRD patients showed more microalbuminuria (21% versus 4.1%; p = 0.003), while retinopathy was more common in patients with DM1 (24% versus 10%; p = 0.044). The prevalences of peripheral neuropathy and nephropathy were similar. Patients with CFRD had lower BMI (p < 0.0001), total cholesterol (p < 0.0001) and HbA1c (p = 0.056) levels, and a lower prevalence of smokers (p < 0.0001). Cholesterol/HDL ratio and diastolic and systolic blood pressure were similar in both groups.ConclusionsThe microvascular complications shown by patients with CFRD are similar to those seen in patients with DM1 but with a lower prevalence of retinopathy and a higher prevalence of microalbuminuria. The latter may reflect the influence of other cystic fibrosis-related factors on renal function.  相似文献   
995.
996.

Background  

Liver function tests (LFTs) are routinely performed in primary care, and are often the gateway to further invasive and/or expensive investigations. Little is known of the consequences in people with an initial abnormal liver function (ALF) test in primary care and with no obvious liver disease. Further investigations may be dangerous for the patient and expensive for Health Services.  相似文献   
997.
998.
Chronic hyperplastic eosinophilic sinusitis (CHES) is a T-helper (Th)2-like, lymphocyte-initiated, eosinophil-rich inflammatory disease. The complex immune interactions required to orchestrate these processes begin with the presentation of antigen by mature dendritic cells to Th lymphocytes that display the appropriate antigen-specific T-cell receptor. The objective of sinus research must be to identify and target that antigen; this will lead to the cure for this condition. This article reviews numerous models that may be responsible for the pathophysiology of this disorder, including putative roles for allergens, bacteria, and bacterial-derived superantigens, as well as recent interest in fungal-derived antigens. Additionally, we speculate that whatever the inciting cause of CHES may be, it is plausible that once initiated, cellular differentiation pathways may lead to the development of an antigen-independent permanent phase. More than one of these may be valid in different subjects and, furthermore, this list almost assuredly does not explain all cases of CHES. The concept that fungal antigens colonizing the sinuses are responsible for CHES represents an intriguing, but unproven, hypothesis. Presently, the case for the fungus remains circumstantial. The case for fungi will be proved only with definitive proof that T-cells within the sinuses are actively responding to fungal antigens present in the sinus and with the further demonstration that removal of those fungal antigens ameliorates the disease.  相似文献   
999.
1000.
Background: Ventricular systolic and diastolic function, as measured by echocardiography, are diminished in patients with a systemic right ventricle (RV). As the clinical implications of these finding remained unknown, we aimed to identify echocardiographic parameters of systolic and diastolic ventricular function that are independent determinants of the clinical condition in these patients. Methods: Forty‐six adult patients (61% male; mean age 33 [range 18–69] years) with a systemic RV underwent echocardiography to assess qualitative and quantitative systolic and diastolic function of the systemic RV and the subpulmonary left ventricle (LV). Uni‐ and multivariate linear regression analyses were performed to identify independent echocardiographic determinants for NYHA class, maximal exercise capacity (V’O2peak) and NT‐proBNP levels. Results: We found qualitative assessment of RV and LV function to be significantly associated with NYHA class (RV: β= 0.26; P = 0.05 and LV: β= 0.82; P < 0.01), V’O2peak (RV: β=?10.4; P < 0.05 and LV: β=?18.4; P < 0.05) and NT‐proBNP levels (RV: β= 0.58; P < 0.01 and LV: β= 1.40; P < 0.001). Tricuspid annulus plane systolic excursion (TAPSE) was significantly associated with NYHA class (β=?0.92; P = 0.001), V’O2peak (β= 18.5; P = 0.05), and serum NT‐proBNP levels (β=?1.00; P < 0.05). Associations between quantitative parameters of systolic subpulmonary LV function and clinical parameters were less distinct. We found no associations between RV and LV diastolic function and clinical parameters. Conclusions: Qualitative function of the systemic RV and the subpulmonary LV, and TAPSE, are determinants of clinical condition in patients with a systemic RV. These patients’ clinical condition could not be determined by echocardiographically measured diastolic RV function, and systolic and diastolic LV function. (Echocardiography 2010;27:1247‐1255)  相似文献   
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