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991.
Newborn screening with tandem mass spectrometry: examining its cost-effectiveness in the Wisconsin Newborn Screening Panel 总被引:3,自引:0,他引:3
OBJECTIVE: To examine the cost-effectiveness of tandem mass spectrometry (MS/MS) in a neonatal screening panel for 14 fatty acid oxidation and organic acidemia disorders in the Wisconsin Newborn Screening Program. STUDY DESIGN: An incremental cost-effectiveness analysis with a hypothetical cohort of 100,000 infants was performed. A threshold of $50,000/QALY (quality-adjusted life-year) was used to determine whether screening for medium-chain acyl-CoA dehydrogenase deficiency (MCAD) alone is cost-effective or whether additional disorders would need to be incorporated into the analysis to arrive at a conclusion regarding the overall cost-effectiveness of MS/MS. RESULTS: Under conservative assumptions, screening for MCAD alone yields an incremental cost-effectiveness ratio of $41,862/QALY. With the use of more realistic assumptions, screening becomes more cost-effective ($6008/QALY) and remains cost-effective so long as the incremental cost of screening remains under $13.05 per test. Adding the incremental costs of detecting the 13 other disorders on the screening panel still yields a result well within accepted norms for cost-effectiveness ($15,252/QALY). CONCLUSIONS: In Wisconsin, MS/MS screening for MCAD alone appears to be cost-effective. Future analyses should examine the cost-effectiveness of alternative follow-up and treatment regimens for MCAD and other panel disorders. 相似文献
992.
Organ preservation surgery for laryngeal cancer 总被引:4,自引:0,他引:4
Tufano RP 《Otolaryngologic clinics of North America》2002,35(5):1067-1080
The open organ preservation surgical procedures are an important part of the head and neck surgeon's armamentarium for treating laryngeal cancer. The principles of organ preservation surgery as they apply to laryngeal cancer must be thoroughly appreciated and strictly applied for oncologic and functional success. The selection of eligible patients for these procedures is an art and requires a keen clinical acumen. The vertical partial laryngectomy and supraglottic laryngectomy have defined clinical applications that are relatively well accepted. The supracricoid laryngectomy continues gaining acceptance as a means of treating more extensive glottic and transglottic lesions while maintaining physiologic speech and swallowing without the need for a permanent tracheostoma. The inability to include and use the open surgical organ preservation approaches in the organ preservation paradigm for larynx cancer severely limits the patient's treatment options. Total laryngectomy and medical organ preservation protocols may not be acceptable to the patient from a quality-of-life standpoint. Therefore, it is incumbent upon the head and neck surgeon to have a thorough understanding of all the options available for treatment in the organ preservation paradigm for laryngeal cancer. These options must be skillfully evaluated as they relate to the patient's disease process and confidently used to provide the best oncologic and functional outcome. 相似文献
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Sherwood CC Broadfield DC Holloway RL Gannon PJ Hof PR 《The anatomical record. Part A, Discoveries in molecular, cellular, and evolutionary biology》2003,271(2):276-285
The cortical circuits subserving neural processing of human language are localized to the inferior frontal operculum and the posterior perisylvian region. Functional language dominance has been related to anatomical asymmetry of Broca's area and the planum temporale. The evolutionary history of these asymmetric patterns, however, remains obscure. Although testing of hypotheses about the evolution of language areas requires comparison to homologous regions in the brains of our closest living relatives, the great apes, to date little is known about normal interindividual variation of these regions in this group. Here we focus on Brodmann's area 44 in African great apes (Pan troglodytes and Gorilla gorilla). This area corresponds to the pars opercularis of the inferior frontal gyrus (IFG), and has been shown to exhibit both gross and cytoarchitectural asymmetries in humans. We calculated frequencies of sulcal variations and mapped the distribution of cytoarchitectural area 44 to determine whether its boundaries occurred at consistent macrostructural landmarks. A considerable amount of variation was found in the distribution of the inferior frontal sulci among great ape brains. The inferior precentral sulcus in particular was often bifurcated, which made it impossible to determine the posterior boundary of the pars opercularis. In addition, the distribution of Brodmann's area 44 showed very little correspondence to surface anatomy. We conclude that gross morphologic patterns do not offer substantive landmarks for the measurement of Brodmann's area 44 in great apes. Whether or not Broca's area homologue of great apes exhibits humanlike asymmetry can only be resolved through further analyses of microstructural components. 相似文献
997.
Bcl-2 expression inhibits liver carcinogenesis and delays the development of proliferating foci 总被引:2,自引:0,他引:2 下载免费PDF全文
Pierce RH Vail ME Ralph L Campbell JS Fausto N 《The American journal of pathology》2002,160(5):1555-1560
Tumor development is thought to require both increased proliferation and inhibition of apoptosis. However, the relationship between cell replication and cell death in liver tumorigenesis is complex because both proliferation and apoptosis increase during hepatocarcinogenesis. To investigate the effect of the anti-apoptotic gene Bcl-2 in liver carcinogenesis, we established a line of double transgenic mice that express transforming growth factor-alpha (TGF-alpha), a liver mitogen, and Bcl-2. Double transgenic mice, TGF-alpha and Bcl-2 single transgenics, and wild type received an injection of diethylnitrosamine at 15 days of age. This alkylating agent induces liver carcinogenesis and its effect is greatly enhanced by TGF-alpha. We report that Bcl-2 expression inhibited diethylnitrosamine-induced liver carcinogenesis and counteracted the enhancing effect of TGF-alpha. Bcl-2 delayed the growth of proliferative foci at the early stages of carcinogenesis and inhibited cell proliferation in these foci. The effect of Bcl-2 on liver carcinogenesis is consistent with its reported ability to interfere with cell replication. The data demonstrate that the expression of an anti-apoptotic gene during liver carcinogenesis causes a delay rather than an increase in tumorigenesis. 相似文献
998.
Ketamine and MK-801 decrease acetylcholine release in the pontine reticular formation,slow breathing,and disrupt sleep 总被引:5,自引:0,他引:5
STUDY OBJECTIVES: Ketamine induces a dissociated state of consciousness by binding to the phencyclidine binding site within the ion channel gated by the N-methyl-D-aspartate (NMDA) receptor. The brain regions and neurotransmitter systems mediating ketamine-induced alterations in arousal remain incompletely understood. This study used in vivo microdialysis to test the hypothesis that ketamine alters acetylcholine (ACh) release in the medial pontine reticular formation (mPRF). DESIGN: Acetylcholine (ACh) release, sleep, and breathing were quantified following systemic ketamine administration. Microdialysis was used to deliver the NMDA-channel blocker dizocilpine maleate (MK-801) and the R(-)-isomer of ketamine into the mPRF while measuring ACh release. SETTING: N/A PARTICIPANTS: N/A INTERVENTIONS: N/A MEASUREMENTS AND RESULTS: Systemically administered ketamine disrupted normal sleep-cycle organization, reduced mPRF ACh release, and significantly slowed rate of breathing. Dialysis delivery of MK-801 to the mPRF significantly decreased respiratory rate and mPRF ACh release. Dialysis delivery to the mPRF of the R(-)-ketamine isomer significantly decreased mPRF ACh release. CONCLUSIONS: Decreased mPRF ACh release caused by systemically administered ketamine was mimicked by mPRF dialysis delivery of MK-801 and the R(-)-ketamine isomer. These data are consistent with the conclusion that systemically administered ketamine may alter arousal and breathing, in part, by altering cholinergic neurotransmission in the mPRF. 相似文献
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