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71.
Knowing one's waist circumference (WC) is a primary step in assessing risk of disease and health disorders. One concern, however, is the accuracy with which WC measurements are taken. This study attempted to determine the effectiveness of a computer-based tutorial (CBT) in teaching previously untrained individuals to properly self-measure WC. Eighty-three subjects used the CBT to learn and perform WC self-measurement. Validity of the subjects’ measurements was determined by comparing their measurements to a traditionally trained and experienced tester's. Bland–Altman and Box–Whisker comparisons revealed an average 1.57 cm bias in the subjects’ WC measurements. Bland–Altman bias plots illustrated agreement between the subjects’ and experienced tester's measurements. Pearson correlation (r=0.97) showed no significant (p<0.0001) difference between the two groups. The results of this experiment suggest that the tested CBT is efficacious in teaching WC self-measurement. The tutorial could be used in the areas of health assessment, standardization, biomedical education and research.  相似文献   
72.
While most births result in a live baby, stillbirth (the birth of a dead baby) occurs in nearly 1 in 110 pregnancies. This study examined whether levels of maternal anxiety and depression are lower amongst mothers who received social support after stillbirth. Using non-probability sampling, data were collected from 769 mothers residing within the USA who experienced a stillbirth within the past 18 months and for whom we have complete data. The study Maternal Observations and Memories of Stillbirth and the website http://www.momstudy.com containing the questionnaire were open in the period 8 February 2004–15 September 2005. Congruent with the family stress and coping theory, mothers of stillborn babies who perceived family support in the period after stillbirth experienced levels of anxiety and depression that were notably lower than those of their counterparts. Nurses, physicians and support groups also were important sources of support after a stillbirth; however, these sources of support alone were not statistically significant in reducing anxiety and depression in grieving mothers. Community interventions should focus on the grieving mother and her family system , including her partner and surviving children.  相似文献   
73.
Serum IgD concentrations were measured in 39 children with Henoch Schonlein purpura (HSP) and 40 control children by means of radial immunodiffusion. Serum IgG, IgA and IgM concentrations in the HSP patients were measured by nephelometry. The geometric mean IgD concentration in children with HSP (16.7 microg/ml) was significantly higher than in control children (9.1 microg/ml; P=0.03). Serial testing in 10 HSP patients revealed no significant change in IgD concentrations over periods ranging from 1 to 12 months. There was no relationship between IgD and IgA concentrations in the HSP patients. Nineteen of the 39 HSP patients (49%) had nephritis. The mean IgD concentration in patients with nephritis (10.7 microg/ml) did not differ from control values, but was significantly lower than the mean IgD level in the remaining 20 patients who did not have nephritis (25.4 microg/ml; P=0.02). These results indicate that serum IgD levels are increased in children with HSP who did not have nephritis. IgD concentrations in patients with nephritis were similar to levels in control children.   相似文献   
74.
Detection of cytomegalovirus DNA in CD34+ cells from blood and bone marrow   总被引:3,自引:1,他引:3  
Infection of hematopoietic progenitor cells with the human cytomegalovirus (HCMV) has been proposed as an explanation for the cytopenias associated with HCMV-related disease. To test this hypothesis, CD34+ cells, which include the hematopoietic progenitors, as well as mature leukocyte populations were purified on a fluorescence- activated cell sorter and analyzed for HCMV DNA by polymerase chain reaction (PCR). A total of 33 samples from 31 immunosuppressed as well as immunocompetent HCMV-seropositive individuals were studied. CD34+ cells were PCR-positive in four of seven bone marrow aspirates from allogeneic bone marrow transplant recipients, in three of eight aspirates from patients with acquired immunodeficiency syndrome, and in the first of two bone marrow samples from an immunocompetent patient with primary HCMV disease. CD34+ cells purified from peripheral blood for autologous and allogeneic transplantation were also analyzed, and 4 of 13 samples were HCMV DNA-positive. Interestingly, two of the four HCMV-positive samples were from healthy allogeneic donors. Among the mature leukocyte populations, the monocytes were most frequently found to be HCMV DNA-positive. No HCMV DNA was detected in the total bone marrow leukocytes of 13 healthy seropositive bone marrow donors or in the CD34+ cell fraction of three further seropositive donors. In conclusion, the data provide strong evidence that CD34+ hematopoietic progenitor cells can be infected with HCMV in immunosuppressed patients, while this cell population was not identified as a major viral reservoir in healthy HCMV-seropositive individuals.  相似文献   
75.
Antibodies to myeloid precursor cells in autoimmune neutropenia   总被引:4,自引:1,他引:4  
Antibodies to mature blood neutrophils and to bone marrow myeloid cells have been described in the sera of some patients with apparent autoimmune neutropenia. To further explore the prevalence and specificities of antibodies to myeloid precursor cells, we evaluated sera from 148 patients with suspected autoimmune neutropenia for the presence of antibodies to neutrophils, to cultured myeloid cell lines, and to highly purified bone marrow myeloid progenitor cells. Using an immunofluorescence flow cytometric assay, we identified IgG antibodies in 42 (28%) of these sera that bound specifically to K562 cells, a multilineage cell line originally derived from a patient with chronic myelogenous leukemia. Twenty-two (15%) of the sera also contained IgG antibodies that bound specifically to the primitive myelomonocytic leukemia cell line KG1a. Twenty-five (17%) of the sera had IgG antibodies to myeloid cell lines in the absence of antibodies to mature neutrophils. There was a trend toward more severe neutropenia in patients with antibodies to K562 cells, without antineutrophil antibodies. In further studies, antibodies from 12 sera bound to mononuclear CD34+ cells that had been purified from normal human bone marrow by an immunomagnetic separation procedure. Moreover, two of these sera suppressed the growth of granulocyte-macrophage colony- forming units (CFU-GM) in methylcellulose cultures. The presence of antibodies to primitive hematopoietic cells in the sera of some patients with suspected immune neutropenia suggests that these antibodies may have a role in the pathogenesis of the neutropenia observed.  相似文献   
76.

Background

Available definition criteria for metabolic syndrome (MS) have similarities and inconsistencies. The aim of this study was to determine the prevalence of MS in a group of Cameroonians with type 2 diabetes, according to the International Diabetes Federation (IDF) and the National Cholesterol Education Programme Adult Treatment Panel III (NCEP-ATP III) criteria, and to assess the concordance between both criteria, and the implications of combining them.

Methods

We collected clinical and biochemical data for 308 patients with type 2 diabetes (men 157) at the National Obesity Center of the Yaounde Central Hospital, Cameroon. Concordance was assessed with the use of the Kappa statistic.

Results

Mean age (standard deviation) was 55.8 (10.5) years and the median duration of diagnosed diabetes (25th?C75th percentiles) was 3?years (0.5?C5.0), similarly among men and women. The prevalence of MS was 71.7% according to the IDF criteria and 60.4% according to NCEP-ATP III criteria. The prevalence was significantly higher in women than in men independently of the criteria used (both p?Conclusions The IDF and NCEP-ATP III criteria do not always diagnose the same group of diabetic individuals with MS and combining them merely increases the yield beyond that provided by the IDF definition alone. This study highlights the importance of having a single unifying definition for MS in our setting.  相似文献   
77.

Background  

Methylphenidate (MPH) is the classic treatment for Attention Deficit Hyperactivity Disorder (ADHD), yet the mechanisms underlying its therapeutic actions remain unclear. Recent studies have identified an oral, MPH dose regimen which when given to rats produces drug plasma levels similar to those measured in humans. The current study examined the effects of these low, orally-administered doses of MPH in rats performing a delayed alternation task dependent on prefrontal cortex (PFC), a brain region that is dysfunctional in ADHD, and is highly sensitive to levels of catecholamines. The receptor mechanisms underlying the enhancing effects of MPH were explored by challenging the MPH response with the noradrenergic α2 adrenoceptor antagonist, idazoxan, and the dopamine D1 antagonist, SCH23390.  相似文献   
78.
79.
We prospectively compared the brain magnetic resonance imagings (MRIs) following Gadolinium-DTPA (Gd-DTPA) injection with unenhanced T2-weighted MRIs in a well-defined population-based group of 76 patients aged 20–57 years with acute optic neuritis (ON). We aimed to evaluate the blood-brain barrier impairment in ON and the interrelationships of findings by CSF analyses and MRI. Lumbar puncture and MRI were performed within a median of 19 and 13 days from onset respectively. MRI showed unenhanced lesions in 22 of 54 patients with monosymptomatic ON (AMON) compared to 19 of 22 patients with ON as part of clinically definite MS (CDMS) (p = 0.0002). Enhanced lesions (sized 2–38 mm) were revealed in 10 out of 54 patients with AMON vs 8 of 22 patients with CDMS (p = 0.06). The number of enhancing lesions in proportion to the number of unenhancing lesions was higher in patients with AMON than in patients with CDMS (p > 0.05). Ten of altogether 30 enhancing lesions were situated periventricularly. An impaired blood-brain barrier judged by increased albumin quotient was found in only five patients. The patients with AMON often had significantly less abnormal intrathecal IgG synthesis (p = 0.02), IgG-index (p = 0.02) and oligoclonal bands (p = 0.04) than did the patients with CDMS. In AMON, the presence of oligoclonal bands was significantly related to abnormal unenhanced and enhanced MRI, p = 0.01 and p = 0.02, respectively. No other significant relationships were observed between the results of MRI and CSF findings, neither in AMON nor in CDMS.  相似文献   
80.
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