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Jennifer E. Reynolds Joanne M. Meyer Barbara Landa Cathy A. Stevens Kathleen S. Arnos Jamie Israel Mary L. Marazita Joann Bodurtha Walter E. Nance Scott R. Diehl 《American journal of medical genetics. Part A》1995,57(4):540-547
Expression of clinical findings of Waardenburg syndrome type 1 (WS1) and type 2 (WS2) is extremely variable. Using our collection of 26 WS1 and 8 WS2 families, we analyzed the occurrence, severity, and symmetry of clinical manifestations associated with WS. We found significant differences between WS1 and WS2 in deafness, and in pigmentary and craniofacial anomalies. Factor analysis was used to identify manifestations which covaried, resulting in 2 orthogonal factors. Since mean factor scores were found to differ when compared between WS1 and WS2, we suggest that these factors could be useful in distinguishing WS types. We found that the WS gene was transmitted from mothers more often than from fathers. We also extensively examined the W-Index, a continuous measure of dystopia canthorum. Our data suggest that use of the W-Index to discriminate between affected WS1 and WS2 individuals may be problematic since 1) ranges of W-Index scores of affected and unaffected individuals over-lapped considerably within both WS1 and WS2, and 2) a considerable number of both affected and unaffected WS2 individuals exhibited W-index scores consistent with dystopia canthorum. Misclassification of families may have implications for risk assessment of deafness, since WS2 families have been reported to have greater incidence of deafness, as confirmed in our study. © 1995 Wiley-Liss, Inc. 相似文献
105.
Frank E. Nulsen Albert Leung David G. Fleming Ronald J. Lorig John A. Bettice Kathleen A. Donlin Wen H. Ko 《Annals of biomedical engineering》1980,8(4-6):505-513
Intracranial pressure (ICP) monitoring is a critical measure for avoiding severe brain dysfunction or brain death by directing
supportive therapy so as to prevent ICP increase severe enough to reduce cerebral blood perfusion. Such situations occur with
brain swelling, increased cerebral vascular volume, and increase in cerebrospinal fluid (CSF) volume. Causes include ischemic
stroke, subarachnoid bleeding, brain contusion, encephalitis (as in Reye's syndrome), and hydrocephalus from meningitis or
neoplasm. When several days of ICP monitoring can direct resolution of the pressure crisis, the invasive direct connection
of an intracranial sensor with external recording device carries only minimal infection risk. Prolonged ICP monitoring for
weeks or months demands telemetry and becomes desirable in a number of chronic disease problems including both congenital
and acquired hydrocephalus where enlarged and pressurized cerebral ventricles develop with reduced absorption of continuously
secreted CSF. Although the primary disturbance in CSF circulation can remain incurable, its palliation by valve-regulated
CSF diversions or shunting can restore normal brain function and in infants permit normal brain development. Missing this
goal can result from failure to maintain a sufficiently normal pattern of CSF dynamics and ICP. Monitoring of the CSF pressure
fluctuations transmitted through an intraventricular catheter provides the most accurate record of ICP pulsations. Therefore,
a pressure sensing module can be “T'd” into an existing shunt system in continuity with the already placed ventricular tube.
The capacity to monitor ICP accurately by telemetry was first established in dogs made hydrocephalic to assure free CSF pulse
through a ventricular catheter (1,2,3, 4,5). The subsequent use of ICP monitoring by telemetry in three patients will be described. 相似文献
106.
Donald G. Payan L. Joseph Wheat Zackarie Brahmi Stephen Ip W. Peter Hansen Robert A. Hoffman Kathleen Healey Robert H. Rubin 《Journal of clinical immunology》1984,4(2):98-107
Circulating T-lymphocyte subpopulations were enumerated in 65 patients with histoplasmosis and correlated with the different clinical manifestations of the disease. Acute pulmonary histoplasmosis, rheumatologic, disseminated, and chronic inflammatory manifestations of histoplasmosis were all associated with a significant elevation above normal of OKT8+ (suppressor-cytotoxic) lymphocytes and a significantly lower than normal OKT4+ (helper-inducer)-lymphocyte to OKT8+-lymphocyte ratio. In contrast, cavitary disease was associated with an increase in OKT4+ lymphocytes, a decrease in OKT8+ lymphocytes, and a higher than normal OKT4/OKT8 ratio. Clinical recovery was associated with normalization of these values. Functional activity determined by coculture techniques correlated closely with T-lymphocyte subset measurements. These distinct subset abnormalities may help monitor immunological aspects of disease activity. 相似文献
107.
The effects of antihypertensive therapy on left ventricular mass in elderly patients 总被引:4,自引:0,他引:4
S P Schulman J L Weiss L C Becker S O Gottlieb K M Woodruff M L Weisfeldt G Gerstenblith 《The New England journal of medicine》1990,322(19):1350-1356
Left ventricular mass sometimes decreases during treatment of hypertension, but this response is inconsistent and its effects on left ventricular function are unknown. In a six-month randomized trial, we studied the ability of verapamil and atenolol to reduce left ventricular mass in 42 elderly patients with hypertension and the effects of this reduction in mass on cardiac function. The mean blood pressure (+/- SE) decreased in both the group that received verapamil (from 171.4 +/- 3.2/93.0 +/- 2.5 mm Hg to 142.9 +/- 2.8/79.0 +/- 2.0 mm Hg) and the group that received atenolol (from 179.6 +/- 4.6/98.5 +/- 2.4 mm Hg to 148.1 +/- 3.3/83.4 +/- 1.2 mm Hg), but the atenolol-treated patients more frequently required the addition of chlorthalidone to achieve blood-pressure reduction (P less than 0.01). Verapamil resulted in a reduction in the left-ventricular-mass index from 104 +/- 5 g per square meter of body-surface area to 85 +/- 5 g per square meter (P less than 0.01). Atenolol did not produce a reduction in the left-ventricular-mass index (109 +/- 9 g per square meter before treatment vs. 112 +/- 10 g per square meter after treatment). Two weeks after the withdrawal of antihypertensive therapy, blood pressure returned to pretreatment values. Nevertheless, in patients whose left ventricular mass had decreased, two measures of diastolic filling, the peak diastolic filling rate to the peak ejection rate, were significantly higher than before treatment (2.42 +/- 0.2 vs. 3.31 +/- 0.4 [P less than 0.05] and 0.61 +/- 0.03 to 0.85 +/- 0.05 [P less than 0.05], respectively). Diastolic filling was unchanged in the group that had no reduction in left ventricular mass. Cardiac output and the ejection fraction at rest and during mild exercise were unchanged in both groups as compared with baseline values. We conclude that left ventricular mass can be reduced in elderly patients with hypertension and mild ventricular hypertrophy who receive antihypertensive therapy. Reduction occurs more frequently with verapamil than with atenolol therapy, increases diastolic filling, and does not impair systolic function. 相似文献
108.
Vijay S. Tonk Kathleen S. Wilson Charles F. Timmons Nancy R. Schneider 《Genes, chromosomes & cancer》1994,11(3):199-202
Short-term cultures of three hepatoblastomas were analyzed cytogenetically. Trisomy 2, trisomy 20, and a deletion of 17p were found as the sole abnormalities, yielding the karyotypes 47,XY, + 2; 47,XX, + 20; and 46,XX,del(17)(p12)/46,XX. This is the first reported case of deletion of 17p as the sole chromosomal abnormality in a hepatoblastoma and the first reported case of trisomy 20 without double minute chromosomes as a sole chromosomal abnormality in hepatoblastoma. 相似文献
109.
Inhibiting complement anaphlytoxin C5a during sepsis may prevent sepsis mortality. Although human anti-C5 antibodies exist, their therapeutic use in microbial sepsis has been avoided because of the hypothesis that inhibiting C5b will prevent formation of the bactericidal membrane attack complex (MAC) and worsen clinical outcome. We wished to test the hypothesis that inhibition of C5 would improve outcomes in sepsis. Sepsis was induced in rats by laparotomy and cecal ligation and puncture (CLP) by an IACUC-approved protocol. Sham animals underwent laparotomy without CLP. Following CLP rats were randomized to receive a single IV dose of purified IgG ant-C5 antibody (Ab) or control IgG Ab. Anti-C5 Ab treated rats (n = 20) had significantly lower mortality vs. controls (n = 21), 20% vs. 52% (P = 0.019, log-rank). Analysis of bacterial load by culture of spleen and liver homogenates showed a reduction in colony forming units in anti-C5 Ab treated rats vs. control IgG (P = 0.003 and 0.009, respectively). Anti-C5 treatment reduced lung injury as measured by total MPO content of lung tissue (P = 0.024). Finally, rats genetically deficient in C6 production, unable to form MAC but capable of producing C5a and C5b, were protected from CLP-induced sepsis mortality. Our results show that in anti-C5 antibody therapy prevents CLP sepsis-induced mortality and improves lung injury. Inhibition of the complement MAC does not increase bacterial load or mortality, therefore, the use of anti-C5 therapy may be beneficial rather than detrimental in sepsis. 相似文献
110.