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Premenstrual symptoms in black and white community samples   总被引:1,自引:0,他引:1  
Premenstrual syndrome specialty clinics are reported to be almost exclusively attended by white women. This racial discrepancy has raised the question of whether there is a lower prevalence or severity of symptoms during the premenstruum among black women. The authors evaluated selected premenstrual symptoms in a representative community-based sample and found no difference in the prevalence or severity of premenstrual symptoms reported by black and white women, except for a higher prevalence of food cravings among blacks. Exploration of broader sociocultural factors may explain the observed racial difference in seeking help for premenstrual complaints.  相似文献   
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The importance of controlling the bioburden in wounds can not be over emphasized. Glycerine based gel sheets have been used extensively to show their bacteriostatic/fungistatic properties. Hoekstra studied animal wounds and compared glycerine dressings with water based dressings and the glycerine showed superior bioburden reduction. Vandeputte showed similar results when comparing hydrogel and hydrocolloid dressings and looked at the histology of the wounds to find differences in the quantities of the types of cells present. The reduced scar formation of wounds are thought to be attributed to the influence of the glycerine on the healing process. Hoestra has reported the dramatic reduction in the inflammation reaction soon after application of the glycerine gel dressing. Studies by Oliveria‐Gandia, Davis, and Mertz showed the glycerine dressings to be more effective than hydrogel or hydrocolloid dressings in reducing bioburden in animal wounds that were inoculated with microbes and also reducing biocounts in appropriate growth medium. Vandeputte conducted a diabetic study(no exclusions) that compared the glycerine dressing (n = 15) with standard protocol(n = 14) for diabetic foot wounds, that showed the test dressing to be far superior. He along with thousands of other nurses around the world have reported the use of glycerine dressings on superficial burns to reduce pain, reduce the chance for infection, reduce scar formation, and to protect the wound from friction and pressure. J. Baksa extensively used the glycerine gel sheets in his burn unit not only for the superficial wounds but also for 3rd and 4th degree burns on children as well as after surgical removal of hypertrophic and keloid scars to prevent reoccurrence. T.M. Baum and M.J. Busuito also reported the use of the glycerine dressing for scar prevention and treatment. The glycerine dressing has been used extensively for te treatment and prevention of pressure ulcers in hospitals, nursing homes, athletic fields, as well as, under casts, splints and braces. R. Horchner reported a >95% reduction in pressure ulcers in a direct comparison to the control and to hydrocolloids.  相似文献   
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Disturbances of visual cognition, visuomotor performance, and visual memory have been described frequently in Huntington's disease (HD). Early stage visual abnormalities could contribute to these deficits. We evaluated visual processing in 20 control subjects who were non-gene carriers at risk for HD, nine presymptomatic gene-positive subjects, and eight subjects with a recent diagnosis of Huntington's disease. Visual perceptual tests of contrast sensitivity and motion discrimination were used to probe early stage visual processing. Extraocular movements were evaluated in a neurologic examination, and the Digit Symbol test was used to test visual motor performance. Contrast sensitivity did not differ among the three groups. Motion discrimination was impaired in HD subjects but not in the presymptomatic gene carriers when compared to gene noncarriers. Among gene carriers, impaired motion discrimination performance was associated with poorer Digit Symbol performance and extraocular abnormalities. These findings suggest that the early stages of HD are associated with disturbances of motion perception as well as disruptions of visual motor and ocular motor performance.  相似文献   
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Inversion recovery (IR), commonly considered a pulse sequence capable of producing T1-weighted images with excellent display of normal anatomy, is versatile: The null point and peak time provide a useful, succinct summary of the properties of IR and its capacity for producing both T1- and T2-weighted images. Shortening of the inversion time (TI) and creation of a short-TI inversion-recovery (STIR) pulse sequence increases sensitivity to malignancy and other abnormalities by making the effects of prolonged T1 and T2 on signal intensity additive and by nulling the signal from fat. The authors examined over 300 patients with various malignancies and compared STIR images with T1- and T2-weighted images obtained at 0.5 T. In 43 cases, signal-difference-to-noise ratios (SD/Ns) were calculated between tumor, fat, and muscle. In general, STIR images demonstrated tumor as a conspicuously high-intensity area in a background of muted, discernible anatomic detail. The good contrast achieved with STIR sequences between tumor and fat (SD/N = 18.1) and tumor and muscle (SD/N = 12.9) consolidated into a single image the information contained separately on T1- and T2-weighted images, which facilitates efficient detection and localization of malignancy.  相似文献   
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