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21.
Transabdominal versus endovaginal pelvic sonography: prospective study   总被引:1,自引:0,他引:1  
Transabdominal and endovaginal pelvic sonograms were obtained in 108 nonpregnant patients referred for pelvic sonography. The studies were independently obtained by two radiologists and interpreted on the basis of identical clinical information. The sonograms were then compared for anatomic detail and abnormalities. A determination was made about which examination, if either, was superior. Follow-up was performed through a review of the medical records and follow-up studies. Overall, the endovaginal study was judged superior in 65 cases (60.2%), equal in 39 (36.1%), and inferior in four (3.7%). The authors conclude that the endovaginal examination can effectively replace the transabdominal examination as the initial approach for routine pelvic sonography.  相似文献   
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Background  

Adolescents are at risk for acquiring sexually transmitted infections (STIs). However, test rates among adolescents in the Netherlands are low and effective interventions that encourage STI testing are scarce. Adolescents who attend vocational schools are particularly at risk for STI. The purpose of this study is to inform the development of motivational health promotion messages by identifying the psychosocial correlates of STI testing intention among adolescents with sexual experience attending vocational schools.  相似文献   
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Normative data on skills of the tongue used in eating are presented. Normal children 2 to 5 years old were studied regarding their preference of placing food either on the right or left side when eating, and they were compared with age-matched Down's syndrome children. In addition, the ability to move food from the right to the left side of the mouth was studied. Normal children underwent a transition from predominantly placing food on the right side at 2 years of age to predominantly placing it on the left side at 4 years of age. Among Down's syndrome children females preferred the right side, and males preferred the left side. The ability to move food from right to left (lateralizing) undergoes a developmental progression from tilting the head to rolling, followed by slow and eventually by smooth movement from one side to the other. Only 15% of the 5-year-olds were able to move food smoothly from side to side. These data provide a baseline against which children with eating problems can be compared.  相似文献   
25.
Phorbol esters sensitize platelets to activation by physiological agonists   总被引:2,自引:1,他引:1  
Siess  W; Lapetina  EG 《Blood》1987,70(5):1373-1381
Phorbol esters such as phorbol 12, 13-dibutyrate (PdBu; 40 to 200 nmol/L) or 12-O-tetradecanoyl phorbol 13-acetate (20 to 80 nmol/L) added to aspirinized platelet-rich plasma (PRP) 5 to 15 seconds prior to various platelet stimuli (epinephrine, ADP, prostaglandin endoperoxide analog U44069, collagen, PAF, or vasopressin) potentiate the rate and extent of aggregation and ATP secretion induced by those agonists. Platelet aggregation, but not secretion, is potentiated at low concentrations of agonists; platelet secretion is potentiated at higher concentrations of the platelet stimuli. Potentiation of platelet responses was also observed when the preincubation time with PdBu was extended to 12 minutes and also occurred in washed platelets. The potentiating effect of phorbol esters is not mediated by formation of arachidonate metabolites or by released ADP. The sensitizing effect of PdBu on platelet aggregation induced by epinephrine is unique, since in contrast to the other platelet stimuli it is also found at maximal concentrations of epinephrine and does not diminish with prolonged preincubation of platelets with PdBu. Activation of protein kinase C ranges from 20% to 80% over control after 1 to 10 minutes of platelet pretreatment with PdBu but dramatically increases after subsequent addition of a stimulus such as vasopressin. In contrast, agonist- induced myosin light chain phosphorylation is reduced after platelet pretreatment with PdBu. The results indicate that protein kinase C activation enhances platelet aggregation and dense granule secretion triggered by physiologic stimuli, although it desensitizes agonist- induced myosin light chain phosphorylation.  相似文献   
26.
Low-level echogenicity in intraventricular hemorrhage versus ventriculitis   总被引:1,自引:0,他引:1  
Grant  EG; White  EM; Schellinger  D; Rosenbach  D 《Radiology》1987,165(2):471-474
Serial cranial sonograms of 55 neonates with large perinatal intraventricular/intraparenchymal hemorrhages and moderate-to-severe posthemorrhagic hydrocephalus were reviewed. In all 55 patients, the ventricles were initially enlarged and filled with anechoic cerebrospinal fluid, which contained discrete hyperechoic fragments of hematoma. Between 7 and 25 days after the initial hemorrhagic episode, however, diffuse, low-level echogenicity appeared in the ventricles of 34 patients. The low-level echogenicity was transient and persisted for 7-59 days (average, 18 days). In 32 patients, low-level echogenicity was a benign finding associated with prior intraventricular hemorrhage. In two patients, the low-level echogenicity was associated with ventriculitis. Low-level echogenicity appeared, increased, then cleared, but reappeared with the onset of ventriculitis in these two patients. Thickening of the ependyma and abnormal periventricular echogenicity, signs of inflammation, were also present. Although low-level echogenicity may commonly be a benign finding, the possibility of ventriculitis should not be ignored.  相似文献   
27.
There is a lack of reliable and valid clinical assessment tools for individuals with loss of ingestive skills. The McGill Ingestive Skills Assessment (MISA) was developed to facilitate the reliable and valid bedside assessment of elderly persons with feeding difficulties. Items were generated by a literature review and selected with the collaboration of a multidisciplinary team. The first version of the MISA comprised 190 items in 7 scales, covering the domains of medical history, mealtime environment, physical characteristics of the patient, food textures consumed, solid ingestion, liquid ingestion, and behaviors related to self-feeding. The first field test for item selection included 50 individuals, aged 60 years and older, living in the community, supervised housing, and long-term care centers. After field testing, 134 items were eliminated due to poor face validity, redundancy, or poor psychometric performance. The remaining 56 items were provided with 4 response categories and were reorganized into 5 scales. The revised version was field tested to determine its preliminary psychometric properties on 33 individuals, 60 years of age and older, residing in a long-term care center. Six items were eliminated due to redundancy after the second field test. Analyses of the revised version resulted in the elimination of another 6 items that were redundant or that demonstrated poor reliability. Internal consistency of all scales is 0.86 and interrater agreement is 0.92. These analyses suggest that the psychometric properties of the MISA are adequate for diagnosis and treatment planning. This supports its readiness for clinical use following further reliability and validity testing with a larger sample Presented in part to the Dysphagia Research Society, Toronto, Ontario, Canada, October 1997, and Burlington, VT, October 1999, and to the American Geriatrics Society, Nashville TN, May 2000.  相似文献   
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