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951.
952.
GS Allen FA Moore CS Cox JT Wilson JM Cohn JH Duke 《Canadian Metallurgical Quarterly》1998,45(1):69-75; discussion 75-8
BACKGROUND: The incidence of hollow viscus injury (HVI) after blunt trauma (BT) is variable, and differences between children and adults have not been well described. The purpose of this study is to determine the age-group-related incidence and characteristics of BT-associated HVI as well as the clinical markers and consequences of delayed diagnosis. METHODS: A 9-year trauma registry review of all patients with HVI. RESULTS: A large sample of patients (19,621) with BT were evaluated (2,550 < or = 14 years old; 17,070 > 14 years old). One hundred thirty-nine of 17,070 (0.8%) adults had HVI compared with 27 of 2,550 (1%) children. HVI occurred more frequently in the duodenum in children (11 of 27) compared with adults (17 of 139) (p < 0.05). Among patients with abdominal wall ecchymosis, 13.5% of children had HVI compared with 10.6% of adults. Delays in diagnosis of HVI occurred in 9 of 27 children compared with 10 of 139 adults (p < 0.0 5). Delayed diagnosis was associated with increased abdominal septic complications in both children (4 of 9) and adults (2 of 10) compared with diagnosis at presentation (p < 0.05). CONCLUSION: HVI occurs with a similar low frequency in both children and adults. Duodenal injuries are more common in pediatric BT patients. Abdominal wall ecchymosis is associated with increased HVI but is less predictive of HVI than previously described. Contrary to previous reports, delays in diagnosis are associated with increased morbidity. 相似文献
953.
RC von Borstel EA Savage Q Wang UG Hennig RG Ritzel GS Lee MD Hamilton MA Chrenek RW Tomaszewski JA Higgins CJ Tenove L Liviero PJ Hastings CT Korch CM Steinberg 《Canadian Metallurgical Quarterly》1998,148(4):1647-1654
Mutants of the HIS1 locus of the yeast Saccharomyces cerevisiae are suitable reporters for spontaneous reversion events because most reversions are topical, that is, within the locus itself. Thirteen mutations of his1-1 now have been identified with respect to base sequence. Revertants of three mutants and their spontaneous reversion rates are presented: (1) a chain termination mutation (his1-208, née his1-1) that does not revert by mutations of tRNA loci and reverts only by intracodonic suppression; (2) a missense mutation (his1-798, née his1-7) that can revert by intragenic suppression by base substitutions of any sort, including a back mutation as well as one three-base deletion; and (3) a -1 frameshift mutation (his1-434, née his1-19) that only reverts topically by +1 back mutation, +1 intragenic suppression, or a -2 deletion. Often the +1 insertion is accompanied by base substitution events at one or both ends of a run of A's. Missense suppressors of his1-798 are either feeders or nonfeeders, and at four different locations within the locus, a single base substitution encoding an amino acid alteration will suffice to turn the nonfeeder phenotype into a feeder phenotype. Late-appearing revertants of his1-798 were found to be slowly growing leaky mutants rather than a manifestation of adaptive mutagenesis. Spontaneous revertants of his1-208 and his1-434 produced no late-arising colonies. 相似文献
954.
The purpose of this article is to examine 10 steps analyzing the financial impact on a periodontal practice accepting a proposed managed care dental plan. It is emphasized that this analysis should be conducted before formally agreeing to accept the proposed plan. The procedures for examining the 10 steps include the use of hypothetical data for a periodontal practice confronted with a discounted fee plan. Each step is identified, discussed, and the hypothetical data are used to develop results presented in a set of tables. The steps in the analysis process include constructing a practice profit and loss statement and developing a dataset of practice characteristics and productivity measures. Other estimates should be made of covered lives, new patient utilization, existing patient utilization, utilization of non-covered services, estimating other sources of revenue and expense, and the impact on capacity utilization of operatories and practice staff. Results are presented in a set of analysis tables. The importance of multiple analyses is discussed as is the importance of analyzing the impact on results from changing assumptions. Some of the higher risk variables faced by the practitioner are identified for submission to risk evaluation to examine the sensitivity of results. Finally, the relationship between the proposed plan and the additional time required by the periodontist to meet the plan's specifications is examined in light of the data developed in the 10 steps and the results tables. 相似文献
955.
956.
957.
GS Goding 《Canadian Metallurgical Quarterly》1998,108(6):863-872
Posterior patterning in the Drosophila embryo requires the action of Nanos (Nos) and Pumilio (Pum), which collaborate to regulate the translation of maternal hunchback (hb) mRNA. Previous work demonstrated that Pum recognizes sites in the 3' UTR of hb mRNA. In this report, we first define the RNA-binding domain of Pum and then show that residues essential for translational repression are embedded within this domain. We also show that Nos and Pum can repress cap-independent translation from an internal ribosome entry site (IRES) in vivo, suggesting that they act downstream of the initial steps of normal, cap-dependent translation. 相似文献
958.
INTRODUCTION: Several lines of evidence suggest that neuroimmune mechanisms may also be involved in neurodegeneration in Parkinson's disease (PD). The potential role of cytokines such as interleukin 6 (IL-6), in the interaction between neurons and immune system has been emphasized by recent findings. IL-6 induces acute phase protein synthesis, differentiation of neuronal cells and improves catecholaminergic and cholinergic cell survival in the brain. SUBJECTS AND METHODS: We determined levels of IL-6 in cerebrospinal fluid (CSF) of untreated parkinsonian patients and age- and sex-matched controls. Intensity of disease was evaluated by the Unified Parkinson's Disease Rating scale. RESULTS: Significantly elevated levels of IL-6 were found in the CSF of parkinsonian patients. Moreover a significant inverse correlation between severity of PD and IL-6 CSF levels appeared. DISCUSSION: Elevated IL-6 levels in the CSF of untreated parkinsonian patients may reflect the original condition in the course of disease. We speculate that an endogenous upregulation of IL-6 synthesis occurs in order to regenerate lesioned neurons probably at an early phase of the degenerative process in PD. 相似文献
959.
V Savarino GS Mela P Zentilin G Lapertosa P Cutela MR Mele C Mansi E Dallorto A Vassallo G Celle 《Canadian Metallurgical Quarterly》1996,22(3):178-181
Short-term cultures from two histologically benign chemodectomas, one from the carotid body and one from the vagal nerve, were analyzed cytogenetically. The former had a small abnormal clone with the karyotype 46,XX,t(3;19)(q21;q13),t(12;15) (p13;q12-14), whereas the majority of the cells from the latter tumor displayed two related abnormal clones: 46,XY,i(I)(q10)/ 46,iderm,add(2)(q37). The findings add to the evidence that chemodectomas are heterogeneous neoplasms and suggest that the heterogeneity may possibly be associated with the site of origin. 相似文献
960.