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The accuracy of the copper sulfate method of determining hemoglobin was investigated under usual blood bank conditions. In our hands this method was found to be grossly inaccurate. Using the cyanmethemoglobin technic, it was demonstrated that 83.9 per cent of females and 80.4 per cent of males rejected as having a low hemoglobin by the copper sulfate method, actually had hemoglobin values above minimum requirements for blood donors. Detailed instruction as to technics and pitfalls of the copper sulfate method was ineffectual in correcting errors as encountered by a large nursing staff carrying out the procedure. Donors found to have acceptable hemoglobin values by the copper sulfate method appeared to be safely accepted as donors; cyanmethemoglobin duplicate checks did not reveal any discrepancies in this group.  相似文献   
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Objective To evaluate the usefulness of early transcranial Doppler ultrasound (TCD) goal-directed therapy after severe traumatic brain injury initiated before invasive cerebral monitoring is available. Design Prospective, observational clinical study. Setting Surgical intensive care unit, university hospital. Patients and participants Twenty-four severely brain-injured patients. Interventions All patients had TCD measurements immediately on admission (T0) and when invasive cerebral monitoring was available (T1). TCD was considered abnormal when two out of three measured values were outside the following limits: Vm < 30 cm/s, Vd < 20 cm/s, PI  > 1.4. When admission TCD was abnormal, attending physicians modified treatment to increase cerebral perfusion pressure. Measurements and results Admission TCD was performed 18 ± 11 min (T0) after admission, whereas cerebral inasive monitoring was available 242 ± 116 min (T1) after admission. At T0, 11 (46%) patients had abnormal TCD values (group 1) and 13 had normal TCD values (group 2); mean arterial pressure was comparable between groups. All group 1 patients received mannitol and/or norepinephrine. At T1, mean arterial pressure was increased compared to admission in group 1 (105 ± 17 mmHg vs. 89 ± 15 mmHg, p < 0.05) and only two patients had still an abnormal TCD. Although group 1 patients had higher intracranial pressure than those of group 2 (32 ± 13 mmHg vs. 22 ± 10 mmHg, p < 0.01), both cerebral perfusion pressure and jugular venous oxygen saturation were comparable between the groups. Conclusions The use of TCD at hospital admission allows identification of severely brain-injured patients with brain hypoperfusion. In such high-risk patients, early TCD goal-directed therapy can restore normal cerebral perfusion and might then potentially help in reducing the extent of secondary brain injury.  相似文献   
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Knowledge of the distribution of foot‐and‐mouth disease (FMD) is required if control programmes are to be successful. However, data on the seroprevalence and incidence of affected villages in developing countries with endemic disease are scarce. This is partly due to resource constraints as well as the logistical challenges of conducting intensive surveys and diagnostic testing in remote locations. In this study, we evaluated the performance of low resolution national‐scale data against high resolution local survey data to predict the FMD serological status of 168 villages in the Mandalay and Sagaing Regions of central Myanmar using both logistic regression and random forest modelling approaches. Blood samples for ELISA testing were collected from approximately 30 cattle per village in both the 6 to 18 month age range and in the over 18 month age range to distinguish between recent and historical exposure, respectively. The results of the animal level tests were aggregated to the village level to provide the outcome of interest (village positive or not positive for FMD), and three explanatory data sets were constructed: using only nationally available data, using only data collected by survey and using the combined survey and nationally available data. The true seroprevalence of FMD at the village level was 61% when only young animals were included, but increased to 87% when all animals were included. The best performing model was a logistic regression model using the combined national and survey data to predict recent infection in villages. However, this still incorrectly classified 40% of villages, which suggests that using national‐level data were not reliable enough for extrapolating seroprevalence in regions where conducting detailed surveys is impractical. Other methods for collected data on FMD such as the use of local reporting should be explored.  相似文献   
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World Journal of Surgery - Massive transfusion (MT) is a lifesaving treatment for hemorrhaging patients. Predicting the need for MT is crucial to improve survival. The aim of our study was to...  相似文献   
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