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101.
RFLP studies were done in 82 (75%) of all known hemophilia A families in the Finnish population (approximately 5 million). Two intragenic RFLPs (Bc1I/F8A, XbaI/p482.6) and two extragenic markers (TaqI/St14, Bg1II/DX13) were used. Among 263 females at risk, carriership could be evaluated with an intragenic marker in 47% and with an extragenic marker in 26%. In 27% of the females, carriership could be neither excluded nor confirmed; 68% of these females were relatives of an isolated patient. Eight recombinations between the factor VIII gene (F8C) and DXS52 (lod 25.02 at theta max 0.06), eight recombinations between F8C and DXS15 (lod 21.91 at theta max 0.05), and two recombinations between DXS52 and DXS15 (lod 33.56 at theta max 0.01) were found. Using multipoint linkage analysis, the most likely order of loci supported by the data was: F8C-DXS15-DXS52-DXS134. RFLP segregation analysis provides a highly useful method of carrier detection and prenatal diagnosis of hemophilia A, but its limitations must be carefully taken into account.  相似文献   
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103.
A comparison was performed between technetium-99m tetrofosmin myocardial perfusion tomography at baseline and after nitrate administration, using a 2-day protocol, and rest-reinjection thallium-201 single-photon emission tomography (SPET) studies in order to assess whether nitrates enhance the detection of viable myocardium with99mTc-tetrofosmin. Fifteen patients with coronary artery disease, previous myocardial infarction and a left ventricular ejection fraction <40% underwent201T1 rest-injection and99mTc-tetrofosmin. baseline-postnitroglycerin (0.4 mg sublingually) SPET studies, within 48 h. Tomograms based on the three spatial planes were divided into 15 segments and regional tracer uptake was quantitatively analysed. Viability was defined as presence of tracer uptake >50% of peak activity on baseline studies or after reversibility. The percentage of peak activity of99mTc-tetrofosmin at baseline correlated with that of 201T1 (r=0.82,P <0.001). On baseline99mTc-tetrofosmin studies, 73 of the 225 segments that were analysed had <50% of peal. activity. Fifteen percent of these segments showed reversibility after nitrate administration, with an increase in99mTc-tetrofosmin uptake from 40%±9% to 57%±9% of peak activity (P=0.003). All reversible segments after nitrate administration had viability criteria on201Tl studies, but 20 segments that were non-viable on99mTc-tetrofosmin. studies were viable on201Tl studies. Using a threshold value of >40% of peak activity, only seven segments remained non-viable on99mTc-tetrofosmin studies. Overall agreement between99mTc-tetrofosmin with nitrates and201Tl-reinjection regarding the presence of myocardial viability was 90%. Detection of myocardial viability with99mTc-tetrofosmin. was enhanced after nitrate administration, correlating with viability criteria observed on thallium studies.  相似文献   
104.
Background: It has been suspected that synthetic colloids may interfere with leukocyte adhesion by down-regulation of endothelial cell adhesion molecules. Although inhibition of endothelial inflammation might reduce leukocyte-related tissue injury, the same mechanism may be detrimental for host defense during severe infection. Regarding the widespread use of colloids, the authors performed a laboratory investigation to determine the mechanisms by which synthetic colloids interfere with leukocyte-endothelial interactions.

Methods: Adhesion molecule expression on native and cytokine-activated endothelium from umbilical veins was measured after pretreatment with gelatin and various preparations of dextran or hydroxyethyl starch. Inhibition of neutrophil adhesion to activated endothelium was examined in a flow chamber by perfusion of untreated and colloid-treated neutrophils over colloid-pretreated endothelium at 2 dyn/cm2. Comparisons were made between untreated controls, colloid-pretreated endothelium, and colloid-cotreated neutrophils.

Results: Intercellular adhesion molecule 1, vascular cell adhesion molecule 1, E-selectin, and P-selectin were not attenuated by any colloid. Accordingly, colloid pretreatment of endothelium alone did not reduce neutrophil adhesion. In contrast, when neutrophils were cotreated by addition of colloids to the perfusate immediately before perfusion, adhesion decreased by 31-51% (P < 0.05) regardless of the colloid type. As indicated by the twofold increased rolling fractions, this reduction was due to an inhibition of neutrophil integrins.  相似文献   

105.
106.
The purpose of this study was to compare different kinetic and semi-quantitative methods for analysing human [18F]FP-beta-CIT studies: plasma input models, simplified (SRTM) and full (FRTM) reference tissue models, standard uptake values (SUV) and SUV ratios (SUVr). Both simulations and clinical evaluations were performed to determine the effects of noise, scan duration and blood volume on Akaike model selection, and on precision and accuracy of estimated parameters. For typical noise levels (COV approximately 2.5%) and scan durations (<90 mins), simulations provided poor fits (Akaike criterion) in case of reversible plasma input models showing a relatively high number of outliers compared with the two-tissue irreversible model. Reference tissue models provided more reliable fits, which were nearly independent of noise and scan duration. For clinical data, two tissue irreversible and reversible plasma input models fitted striatum curves equally well (Akaike criterion). BP with plasma input models were less precise and contained more outliers than BP obtained with SRTM or FRTM. Among all methods tested, SRTM showed the highest contrast between patients and controls. When differentiating between patients and controls, SUVr performed almost equally well as SRTM, although contrast between striatum and background was lower. In conclusion, SRTM provided BP estimates with the highest precision and accuracy. Moreover, SRTM provided good contrast between patients and controls, and between striatum and background. SRTM is therefore the method of choice for quantitative [18F]FP-beta-CIT studies. SUVr might be an alternative for larger clinical trials.  相似文献   
107.
BACKGROUND: Sevelamer hydrochloride was recently proposed as a phosphate binder to prevent hypercalcaemia in place of calcium alkaline salts in dialysis patients. So far, it has been evaluated only in patients receiving calcitriol, without comparison with CaCO(3) alone, although the latter was found to be as effective as the combination of calcitriol and Al(OH)(3) in suppressing parathyroid hormone (PTH) without inducing hypercalcaemia and to have a better lowering effect on serum phosphate. Moreover, this bile salt binder may decrease serum 25-OH vitamin D. Therefore, we compared for 5 months two strategies for controlling moderate hyperparathyroidism: CaCO(3) alone vs sevelamer in conjunction with measures to increase calcium balance. METHODS: Forty-two patients were randomized: 21 continued their treatment with 4.8 g/day CaCO(3) and 21 were switched to sevelamer (initial dose: 2.4 g/day, increased to 4.4 g/day). Each month, when serum-corrected calcium decreased below 2.30 mmol/l, dialysate calcium was increased or alphacalcidol was given at each dialysis session, according to serum PO(4) levels. The following parameters were monitored: serum Ca, PO(4), bicarbonate and protein, weekly; and serum PTH, 25-OH vitamin D and total, LDL and HDL cholesterol monthly. RESULTS: Except for higher serum phosphate at month 1, lower serum bicarbonate at month 2 and lower LDL cholesterol at month 5 in the sevelamer group, no difference was found between the two groups. Compared with baseline levels, PTH increased and 25-OH vitamin D decreased significantly in both groups, these two parameters being inversely correlated. CONCLUSIONS: Given comparable control of plasma calcium, phosphate and 25-OH vitamin D, PTH control is comparable in both strategies. Sevelamer does not induce greater vitamin D depletion than CaCO(3). The transient decrease of serum bicarbonate after discontinuation of CaCO(3) in the sevelamer group suggests a less optimal prevention of acidosis. The sevelamer-induced decrease in LDL cholesterol gives this drug a potential advantage in cardiovascular prevention.  相似文献   
108.
Patients' health status as well as patients' judgements of care are used for assessing patients' perspectives, but the relation between those two concepts is unclear. In this study we explored whether health status predicts patients' judgements of the quality of general practice care. Hand-distributed and mailed surveys were performed by 28 general practitioners in The Netherlands. Chronically ill patients were approached when visiting the general practice or drawn from the practice registers. Health status was measured by WONCA/COOP charts, and patients' judgements by the CEP, a previously validated questionnaire. The response rate was 63% (n=762). When controlled for other patient characteristics, a poor overall health predicted less positive judgements of medical care, information, counselling, relation and communication, continuity of care and the organization of appointments (p[lessthan]0.01). Poor mental well-being predicted less positive judgements of the cooperation between care providers and a stronger need for more care (p[lessthan]0.001). The four other aspects of health status did not predict the patients' judgements. Judgements about the premises and the availability for emergencies were not predicted by health status. It can be concluded that a multidimensional approach should be used for interpreting the relations between patients' health status and their judgements of general practice care.  相似文献   
109.
Hypothesis: Does occupational exposure to solvents in combination with alcohol intake give rise to acquired color vision defects? Method: A total of 138 individuals exposed to solvents (toluene, xylene, trichloroethylene, tetrachloroethylene) were examined using Lanthony’s D-15 test and compared with 100 nonexposed controls. The extent of color vision loss was quantitatively assessed based on Bowman’s color confusion index (CCI). A cumulative exposure index was calculated from the hours of exposure per day and the years of exposure. In 30 persons who were exposed to trichloroethylene and tetrachloroethylene, urinary trichloroacetic acid was assessed as a parameter of exposure. Alcohol intake was calculated as based on interviews of patients in grams of ethyl alcohol per week. Results: Individuals who consumed more than 250 g alcohol/week and were simultaneously exposed to solvents showed a significantly elevated CCI (P = 0.0044). No significant correlation emerged between trichloroacetid acid excretion in the urine or the cumulative exposure index and the CCI. Conclusion: The combination of alcohol intake and occupational exposure to solvents discloses the risk of acquired subclinical color vision defects.  相似文献   
110.
Existing knowledge and present experience relating to the indications for imaging techniques in trauma surgery were summarised, screened and considered in different ways by representatives of various professional scientific bodies, with the aim of finding what procedures should be implemented as the primary examination techniques after a careful clinical examination when particular posttraumatic situations affecting the knee, foot, ankle, or hand were found. In the course of an interdisciplinary consensus conference the evidence-based recommendations prepared by a panel were discussed and modified, giving rise to statements on the suitability of the given imaging techniques in 28 different clinical situations immediately after a clinical examination, based on scientific evidence and medical consensus. The degree of consensus was measured and carefully documented. These statements were transformed into decision algorithms and presented to doctors working in accident and emergency medicine during a conference on trauma surgery, with the aim of.measuring the acceptance of the statements among those attending the trauma surgery meeting. The remarks made by the participants during the discussion and the results of the acceptance measurements clearly show the need for further discussion among experts.  相似文献   
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