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941.
The authors report on a 2-year-old boy in whom pneumatosis intestinalis (PI) and portal vein gas (PVG) resulted from blunt abdominal trauma after child abuse. The presumed pathophysiology of PI and PVG is mechanical in this setting. Its presence establishes mucosal injury but does not necessarily imply intestinal necrosis. 相似文献
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944.
Mutations at the CLAVATA2 (CLV2) locus of Arabidopsis result in enlarged shoot and flower meristems, as well as alterations in the development of the gynoecia, flower pedicels, and stamens. The shoot and flower meristem phenotypes of clv2 mutants are similar to weak clv1 and clv3 mutants. We present genetic analysis that CLV2 may function in the same pathway as CLV1 and CLV3 in the regulation of meristem development, but function separately in the regulation of organ development. We also present evidence that clv2 phenotypes are altered when the mutants are grown under short-day light conditions. These alterations include flower-to-shoot transformations, as well as a nearly complete suppression of the flower phenotypes, indicating that the requirement for CLV2 changes in response to different physiological conditions. The stm-1 mutation dominantly suppresses clv2, and clv2 mutations suppress the strong stm-1 allele, but not the weak stm-2 allele. 相似文献
945.
JL Taylor-Roth PV Malven DE Gerrard SE Mills AL Grant 《Canadian Metallurgical Quarterly》1998,120(3):357-363
The successful use of proteins in pharmaceutical and other commercial applications requires close examination of their relative fragility. Because of the resultant enhanced stability, proteins are often formulated in the solid state, even though dehydration tends to alter their structure. Even in the solid form, however, proteins may become inactivated due to various deleterious processes, e.g., aggregation. This review focuses on such mechanisms, with an emphasis on case studies conducted in our laboratory. Proteins which have both disulfide bonds and free thiols may aggregate via thiol-disulfide exchange, and this process may be facilitated by lyophilization-induced structural perturbations. For proteins possessing disulfides but not free thiols, aggregation also may occur when native disulfides are beta-eliminated, thus giving rise to thiol species which can catalyze disulfide scrambling. Other deleterious processes have also been uncovered, including a formaldehyde-mediated aggregation of formalinized vaccines. It is illustrated how knowledge of such deterioration pathways makes possible the rational development of stable solid protein formulations. 相似文献
946.
Jack W. Reich Victoria Dillon Ursula F. Fritsch Karen K. Church 《Drug development and industrial pharmacy》1987,13(4):739-802
This paper examines in detail the Waxman/Hatch Act and the NDA Rewrite, from both an implementation point of view and from a world-wide research and development perspective. The central theme of these regulatory changes appears to be consistent with U.S. drug policy of the past two decades, i.e., cost containment, primarily, followed by uniformity and efficiency in the regulatory review process. These recent changes, just as the 1962 Drug Ammendments 22 years earlier, will continue to have profound effects upon the sites at which pharmaceutical research and development is carried out. 相似文献
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948.
Mortality determinants in massive pediatric burns. An analysis of 103 children with > or = 80% TBSA burns (> or = 70% full-thickness) 总被引:1,自引:0,他引:1
SE Wolf JK Rose MH Desai JP Mileski RE Barrow DN Herndon 《Canadian Metallurgical Quarterly》1997,225(5):554-65; discussion 565-9
OBJECTIVE: Survivors and nonsurvivors among 103 consecutive pediatric patients with massive burns were compared in an effort to define the predictors of mortality in massively burned children. SUMMARY BACKGROUND DATA: Predictors of mortality in burns that are used commonly are age, burn size, and inhalation injury. In the past, burns over 80% of the body surface area that are mostly full-thickness often were considered fatal, especially in children and in the elderly. In the past 15 years, advances in burn treatment have increased rates of survival in those patients treated at specialized burn centers. The purpose of this study was to document the extent of improvement and to define the current predictors of mortality to further focus burn care. METHODS: Beginning in 1982, 103 children ages 6 months to 17 years with burns covering at least 80% of the body surface (70% full-thickness), were treated in the authors' institution by early excision and grafting and have been observed to determine outcome. The authors divided collected independent variables from the time of injury into temporally related groups and analyzed the data sequentially and cumulatively through univariate statistics and through pooled, cross-sectional multivariate logistic regression to determine which variables predict the probability of mortality. RESULTS: The mortality rate for this series of massively burned children was 33%. Lower age, larger burn size, presence of inhalation injury, delayed intravenous access, lower admission hematocrit, lower base deficit on admission, higher serum osmolarity at arrival to the authors' hospital, sepsis, inotropic support requirement, platelet count < 20,000, and ventilator dependency during the hospital course significantly predict increased mortality. CONCLUSIONS: The authors conclude that mortality has decreased in massively burned children to the extent that nearly all patients should be considered as candidates for survival, regardless of age, burn size, presence of inhalation injury, delay in resuscitation, or laboratory values on initial presentation. During the course of hospitalization, the development of sepsis and multiorgan failure is a harbinger of poor outcome, but the authors have encountered futile cases only rarely. The authors found that those patients who are most apt to die are the very young, those with limited donor sites, those who have inhalation injury, those with delays in resuscitation, and those with burn-associated sepsis or multiorgan failure. 相似文献
949.
The initial management of localized penile carcinoma determines the probability of recurrence. Although potentially disfiguring, the management of recurrent carcinoma of the penis requires aggressive surgical resection of both the primary lesion and nodal sites to effect the best chance for long-term survival. 相似文献
950.