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Human herpesviruses are associated with morbidity and mortality in persons with compromised immune systems, including patients infected with human immunodeficiency virus (HIV). To investigate the basis for this association, the levels of all 8 human herpesviruses (herpes simplex virus, types 1 and 2, varicella-zoster virus, cytomegalovirus, Epstein-Barr virus, and human herpesvirus 6, human herpesvirus 7, and human herpesvirus 8) were measured with the quantitative polymerase chain reaction (PCR). Viral DNA was measured in the whole blood of 20 HIV-infected patients and compared with levels in 20 healthy blood donors. There was no significant difference in the frequency of virus detection of the 8 human herpesviruses between HIV-infected patients and healthy adults. These results indicate that HIV infection is not associated with a general increase in the circulating levels of human herpesviruses, and suggest that quantitative PCR analysis is superior to qualitative PCR analysis for detection of clinically relevant disease in HIV-infected patients.  相似文献   
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Tests of memory in narcoleptics   总被引:3,自引:0,他引:3  
A E Rogers  R S Rosenberg 《Sleep》1990,13(1):42-52
This study attempted to evaluate the validity of self-reports of memory deficits in narcoleptics by comparing the scores of these patients with the scores of matched control subjects on standardized tests of memory function. After completing a short interview designed to elicit qualitative information about memory difficulties, 30 narcoleptic subjects and 30 control subjects completed the Wechsler Memory Scale (WMS), Rey-Auditory Verbal Learning Test, the Rey Complex Figure Test, Strub and Black's List of Letters, and the Symbol Digits Modalities Test (SDMT). In addition, the Profile of Mood States (POMS) was used to detect variation in performance due to anxiety or fatigue. Continuous polygraphic recordings were obtained during the testing to detect any changes in alertness. Subjects with narcolepsy experienced more difficulty in maintaining attention than control subjects, as evidenced by significantly more perseveration errors (p less than or equal to 0.01) on Strub and Black's List of Letters. Despite differences in their ability to sustain attention, there were no significant differences between narcoleptic and control subjects on measures of concentration (Digit Span from the WMS, and the SDMT). Furthermore, there was no objective evidence of memory impairment when the scores of narcoleptic and control subjects were compared on standardized tests of immediate and delayed recall, as well as on tests of verbal and visual memory.  相似文献   
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Clinical laboratory tests are increasingly being used to evaluate individuals for osteoporosis and other metabolic bone diseases. Serum bone alkaline phosphatase (AP) [EC 3.1.3.1, orthophosphoric-monoester phosphohydrolase (alkaline optimum)] and osteocalcin are used to assess osteoblastic activity. Although methods for assessing relative amounts of AP isoenzymes continuously appear in the literature, no single method is satisfactory for quantification. Polyacrylamide gel electrophoresis with densitometric scanning combined with two-point heat inactivation was used to obtain quantitative values for AP isoenzymes. Serum bone AP concentrations correlated positively and significantly with serum osteocalcin concentrations obtained by radioimmunoassay for women. Men had significantly higher total alkaline phosphatase and bone AP than women, whereas liver AP concentrations did not differ between the two groups. Bone AP correlated negatively and significantly with age in men, but not women. Osteocalcin concentrations tended to be higher in men, but not significantly.  相似文献   
75.
CSnrc, a new user-code for the EGSnrc Monte Carlo system is described. This user-code improves the efficiency when calculating ratios of doses from similar geometries. It uses a correlated sampling variance reduction technique. CSnrc is developed from an existing EGSnrc user-code CAVRZnrc and improves upon the correlated sampling algorithm used in an earlier version of the code written for the EGS4 Monte Carlo system. Improvements over the EGS4 version of the algorithm avoid repetition of sections of particle tracks. The new code includes a rectangular phantom geometry not available in other EGSnrc cylindrical codes. Comparison to CAVRZnrc shows gains in efficiency of up to a factor of 64 for a variety of test geometries when computing the ratio of doses to the cavity for two geometries. CSnrc is well suited to in-phantom calculations and is used to calculate the central electrode correction factor Pcel in high-energy photon and electron beams. Current dosimetry protocols base the value of Pcel on earlier Monte Carlo calculations. The current CSnrc calculations achieve 0.02% statistical uncertainties on Pcel, much lower than those previously published. The current values of Pcel compare well with the values used in dosimetry protocols for photon beams. For electrons beams, CSnrc calculations are reported at the reference depth used in recent protocols and show up to a 0.2% correction for a graphite electrode, a correction currently ignored by dosimetry protocols. The calculations show that for a 1 mm diameter aluminum central electrode, the correction factor differs somewhat from the values used in both the IAEA TRS-398 code of practice and the AAPM's TG-51 protocol.  相似文献   
76.
Inhibins and activins are dimeric hormones which share common subunits and which have diverse endocrine and paracrine roles in regulating reproductive function. Endometrial expression of inhibin alpha, ssA and ssB subunits was examined by immunohistochemistry and in-situ hybridization, across the menstrual cycle and in early pregnancy. All three subunits were found to be expressed in endometrium, primarily by glandular epithelium in the early stages of the cycle. Following the onset of decidualization, expression of alpha, ssA and ssB subunits was up-regulated in decidualized stromal cells. A marked down-regulation of alpha subunit was detected in glandular epithelium, whilst expression of ssA and ssB subunits was maintained. This pattern was consistent in decidua from early pregnancy and additionally in endometrium from women using progestin-only contraceptives, either subdermal implants (Norplant((R))) or levonorgestrel-releasing intrauterine systems (Lng-IUS). Immunostaining was also observed for both ssA and ssB subunits in subpopulations of endometrial leukocytes, identified to be distinct subsets of macrophages, neutrophils and mast cells. Potential paracrine roles for activins may be envisaged in facilitating tissue remodelling during decidualization, in tissue repair following menstruation, and additionally in modulating premenstrual inflammatory events.  相似文献   
77.
The Downriver Treadmill Team, a Phase II and Phase III outpatient cardiac rehabilitation program, is presented as a prototypical successful program. The qualities and attributes of this program are discussed as a means to actively promote cardiac rehabilitation directly to the consumer.  相似文献   
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