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21.
A multi-centre evaluation of the Behring ELISA Processor II in connection with the Enzygnost-tests from Behringwerke was performed by 3 laboratories following the ECCLS Guidelines for the Evaluation of Analysers in Clinical Chemistry. The performance characteristics were studied with analytical tests for anti-HBs1), HBsAg and anti-CMV2). This evaluation represents, to our knowledge, the first trial in clinical virology with guidelines primarily designed for clinical chemistry. The evaluation revealed that the highly automated Behring ELISA Processor II is a reliable tool in the virological laboratory. The data obtained showed low imprecision and good accuracy. The washing unit proved to be very efficient. No carry-over of reagents was detected in the dispenser system. Several improvements for further developments of the analyser are suggested. This multi-centre study has shown that the ECCLS protocol can be used to evaluate analysers and test systems in clinical virology.  相似文献   
22.
In vivo 1H MRS can be used to detect and quantify the lactate resonance at 1.3 ppm provided that overlapping lipid resonances are eliminated. A homonuclear spectral editing method was developed to acquire uncontaminated 1H spectra of lactate with adiabatic pulses. An advantage of the adiabatic pulse sequence is the ability to induce uniform flip angles and to maximize sensitivity in applications employing surface coil transmitters which produce highly inhomogeneous B1. Glycolytic activity in an intracerebral C6 glioma in rats was monitored by using adiabatic editing sequences to observe [3-13C]lactate produced from infused [1-13C]glucose. Acute hyperglycemia (serum glucose >22 mM, n = 10) had no significant effect (P = 0.08) on the total ([12C]+ [13C]) tumor lactate signal intensity.  相似文献   
23.
New Substances from the Essential Oils of Artemisia-Species*), III: α-Cadinol α-Cadinol is a tertiary sesquiterpenic alcohol. For the first time it has now been found in the volatile oil of Artemisia vulgaris L. var. vulgatissima. Its identity was established by physicochemical and spectroscopic methods.  相似文献   
24.
The aim of this study was to define the frequency and clinical relevance of cytokeratin positive metastatic tumor cells in the peripheral circulation of patients with stage IV breast cancer. Peripheral blood was collected from 32 consecutive patients with metastatic breast cancer and 23 healthy donors. Tumor cells were enriched using positive selection with anti-HEA125-microbeads and cytospins were prepared of the positive selection eluate. Slides were incubated with a Fab2 fragment of the pancytokeratin antibody A45-B/B3 conjugated with alkaline phosphatase (AKP) and a CAM5.2-AKP monoclonal antibody and developed with an alkaline phosphatase anti-alkaline phosphate reaction (APAAP). All samples were evaluated using light microscopy and an automated image analysis system. In 8/32 (25%) patients cytokeratin positive (CK+) cells could be detected after anti-HEA125 enrichment in the peripheral blood whereas in none out of 23 healthy donors. One to 1000 (median 5) positive cells per patient sample were observed and cluster of tumor cells in one patient. Automated image analysis was as powerful in detecting micrometastases as conventional light microscopy. All patients with CK+ cells in the peripheral circulation (8/8, 100%) showed progressive disease at the time-point of blood draw whilst only 9/24 (37.5%) showed disease progression without detection of positive cells. The median overall survival of CK+ patients was 4+/-2 months compared to 13+/-7 months of CK- patients (p<0.001). CK+ cells are detectable in the peripheral circulation of 25% of patients with metastatic breast cancer after positive selection with anti-HEA125. Detection of tumor cells in the peripheral circulation might be correlated with progression of disease and shorter overall survival.  相似文献   
25.
BACKGROUND: During surgical coronary revascularisation hemodynamics and myocardial contractility can be affected. This in vivo study aimed to determine the effects of different operative techniques on hemodynamics and regional myocardial perfusion. METHODS: In 24 pigs IMA to LAD bypass was constructed using ECC (n = 8) and cardioplegic arrest, OPCAB techniques (n = 8), or the Impella elect 100 support device (n = 8). 8 animals received a sham operation. Mean arterial pressure (MAP), cardiac output (CO), and left ventricular pressure (LVP, LVdp/dt) were recorded. Regional myocardial perfusion (RMP) of both ventricles was assessed by fluorescent microspheres. RESULTS: MAP significantly decreased during revascularisation in all groups ( p < 0.05), staying below preoperative values thereafter ( p < 0.05). After ECC norepinephrine was administered to maintain MAP. CO and LVdp/dt were impaired more distinctly during OPCAB than with Impella ( p < 0.05) during subsequent recovery. RMP showed global reactive hyperemia during early reperfusion after ECC, remained unchanged in OPCAB, and showed low flow during and after Impella pump run ( p < 0.05). CONCLUSIONS: ECC led to hemodynamic impairment with post-ischemic reactive hyperemia. OPCAB created hemodynamic depression but left RMP unchanged. Hemodynamic depression can be reduced by the Impella pump, however regional myocardial blood flow is decreased.  相似文献   
26.
Despite human leukocyte antigen (HLA) identity between donor and recipient, several patients develop acute graft-versus-host disease (aGVHD) after hematopoetic stem cell transplantation (HSCT) because of minor histocompatibility antigen (mHag) incompatibilities. The impact of multiple mHag disparities on the clinical outcome after HSCT still remains to be determined. We studied the genomic polymorphisms of HA-1, CD31, and CD49b and correlated mHag distribution with the occurrence of aGVHD after HSCT from HLA-matched sibling and unrelated donors. All 163 patients examined in our single-center study underwent HSCT for chronic myeloid leukemia in the first chronic phase. HA-1 and CD31 disparities are associated with increased aGVHD incidence in a subgroup of patients who test HLA-B44 supertype positive in univariate analysis. However, in a multivariate analysis, only increased patient age was confirmed as an independent aGVHD risk factor. Our findings indicate that the impact of mHag disparity on aGVHD development in HSCT from HLA-matched sibling and unrelated donors seems to be subordinated to classic aGVHD risk factors.  相似文献   
27.
28.
The Bayer-activities of daily living (B-ADL) is a brief and internationally applicable ADL instrument which has been validated in three European countries. The B-ADL has been developed to provide a tool for the assessment of functional deficits in performance of every day tasks as they are observed in mild to moderate stages of dementia. The B-ADL has been constructed for use in clinical trials as well as in clinical practice. From an international perspective the major application is the evaluation of treatment effects in clinical studies and the current study was to validate the Korean version of the B-ADL. The B-ADL was administered to a total of 129 subjects with varying degrees of cognitive decline. A substantial cross-sectional correlation between B-ADL and MMSE scores was found. The internal consistency of B-ADL was above 0.98. A factor analysis revealed that a one factor solution accounted for most of the total variance. The B-ADL global score significantly increased as the severity of dementia, assessed by global deterioration scale increased from stage 1 to 5. Test-retest reliabilities of B-ADL global score and each item were very high. All of these results were very similar to those from three European countries except for the proportion of 'non-applicability' in some ADL items. These findings provide evidence that the Korean version of B-ADL can be useful not only for clinical purposes but also for international multicentre studies.  相似文献   
29.
BACKGROUND: In primary pulmonary hypertension, aerosolized prostanoids selectively reduce pulmonary vascular resistance and improve right ventricular function. In this study, hemodynamic effects of inhaled iloprost, a stable prostacyclin analogue, were evaluated in patients with chronic thromboembolic pulmonary hypertension (CTEPH) before and early after pulmonary thromboendarterctomy (PTE). METHODS: Ten patients (mean age 49 years old [32 to 70 years old], New York Heart Association functional class III and IV) received a dose of 33 micro g aerosolized iloprost immediately before surgery (T1), after intensive care unit admission (T2), and 12-hours postoperatively (T3). Effects on pulmonary and systemic hemodynamics and gas exchange were recorded and compared with preinhalation baseline values. RESULTS: Preoperatively, inhaled iloprost did not significantly change mean pulmonary artery pressure (mPAP), cardiac index (CI), or pulmonary vascular resistance (PVR). Postoperatively, inhaled iloprost induced a significant reduction of mPAP and PVR and a significant increase of CI at T2 and T3. Preinhalation versus postinhalation PVR was as follows: at T1, 847 versus 729 dynes. s. cm(-5), p = 0.45; at T2, 502 versus 316 dynes. s. cm(-5), p = 0.008; and at T3, 299 versus 227 dynes. s. cm(-5), p = 0.004. CONCLUSIONS: In patients with CTEPH, inhalation of iloprost elicits no significant pulmonary vasodilation before surgery, and may have detrimental effects on systemic hemodynamics. Postoperatively, it significantly reduces mPAP and PVR, and enhances CI. Following PTE, inhalation of iloprost is useful to improve early postoperative hemodynamics.  相似文献   
30.
Methylenetetrahydrofolate reductase (MTHFR) is involved in folate metabolism and plays a role in DNA biosynthesis, methylation, and repair in actively dividing cells. A common 677C>T polymorphism in the gene for MTHFR, leading to a thermolabile enzyme with decreased activity, has been associated with reduced plasma folate levels and elevated homocysteine levels and could be a risk factor for breast cancer. In the present case-control study, MTHFR genotype was determined in 500 women with clinically verified breast cancer and 500 female age-matched healthy control subjects. The homozygous TT genotype was found in 13.0% patients and 13.1% controls (P = n.s.). The odds ratio of TT homozygotes for breast cancer was 0.99 (95% confidence interval 0.68–1.43). The MTHFR genotype was furthermore not associated with tumor size, histological grading, estrogen or progesterone receptor status and age at diagnosis. In a subgroup of 116 premenopausal patients, no increased frequency of the homozygous 677T genotype was found (13.8%). Therefore, we conclude that the MTHFR 677C>T polymorphism is not associated with individual susceptibility to breast cancer.  相似文献   
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