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51.
The Chudley-McCullough syndrome, an autosomal recessive condition first reported by Chudley et al. [1997], comprises profound sensorineural hearing loss and hydrocephalus secondary to an obstruction of the foramen of Munro. We describe two more sibs with this condition. One girl had sensorineural hearing loss and hydrocephalus due to obstruction of the foramen of Munro. Incidentally she was also found to carry a full mutation in the FMR1 gene. The older sister had profound sensorineural hearing loss and hydrocephalus not due to obstruction of the foramen of Munro; she also had callosal dysgenesis, gray matter heterotopia, cortical dysplasia, and cerebellar dysgenesis. Thus, the Chudley-McCullough syndrome may include hydrocephalus not necessarily related to obstruction of the foramen of Munro and other structural brain abnormalities. 相似文献
52.
Jacques Lemire 《Zeitschrift für Rheumatologie》2000,12(2):I24-I27
Summary The active vitamin D metabolite, 1,25-dihydroxyvitamin D3 [1,25-(OH)2D3], exerts immunosuppressive activity. At a cellular and molecular level, the hormone preferentially targets helper T cell activity (Th1) by inhibiting the secretion of both IL-2 and IFN-% by Th1 and by suppressing the secretion pro-Th1 cytokine IL-12 by antigen-presenting cells. The active metabolite further inhibits class II antigen expression and enhances suppressor cell activity. In animal models of autoimmunity, 1,25-(OH)2D3 prevents the development of experimental autoimmune encephalomyelitis, reduces the incidence of diabetes, and attenuates murine lupus. The hormone also prolongs graft survival in animal models of transplantation. In humans, non-classical use of 1,25-(OH)2D3 has led to an anti-proliferative effect in psoriasis, anti-neoplastic effect in prostate cancer, and immunomodulatory effect in scleroderma. The development of less hypercalcemic analogs might open a new therapeutic area for vitamin D3. 相似文献
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54.
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
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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
57.
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58.
59.
60.
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