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71.
72.
LA Smith DE Barker CW Chase LB Somberg WB Brock RP Burns 《Canadian Metallurgical Quarterly》1997,63(12):1102-7; discussion 1107-8
The purpose of this review is to present a 4-year experience with the vacuum pack technique of temporary abdominal closure. From April 1992 to December 1996, 171 vacuum packs were performed on 93 patients. Eighty-seven vacuum packs were performed on 38 general surgical patients, and 84 vacuum packs were performed on 55 trauma patients. Overall hospital mortality was 32 per cent. Methods of achieving permanent wound closure varied in 73 patients. Four patients (4.3%) developed enterocutaneous fistulae; four patients developed intra-abdominal abscesses (4.3%). There were no eviscerations. Management of the complicated intra-abdominal process is discussed: 1) the decision to manage the abdomen in an open fashion; 2) which method of temporary closure to use; 3) subsequent explorations; 4) when the abdomen should be closed; 5) which type of closure to use; and 6) when the abdominal wall should be revised (herniorrhaphy). The vacuum pack is the method of choice for open abdomen management and temporary abdominal closure at our institution. With careful subsequent management, good patient outcome can be achieved. 相似文献
73.
Tailbiting MAP decoders 总被引:4,自引:0,他引:4
We extend the MAP decoding algorithm of Bahl et al. (1974) to the case of tail-biting trellis codes. An algorithm is given that is based on finding an eigenvector, and another that avoids this. Several examples are given. The algorithm has application to turbo decoding and source-controlled channel decoding 相似文献
74.
HP Selker JR Beshansky JL Griffith TP Aufderheide DS Ballin SA Bernard SG Crespo JA Feldman SS Fish WB Gibler DA Kiez RA McNutt AW Moulton JP Ornato PJ Podrid JH Pope DN Salem MR Sayre RH Woolard 《Canadian Metallurgical Quarterly》1998,129(11):845-855
BACKGROUND: Approximately 6 million U.S. patients present to emergency departments annually with symptoms suggesting acute cardiac ischemia. Triage decisions for these patients are important but remain difficult. OBJECTIVE: To test whether computerized prediction of the probability of acute ischemia, used with electrocardiography, improves the accuracy of triage decisions. DESIGN: Controlled clinical trial. SETTING: 10 hospital emergency departments in the midwestern, southeastern, and northeastern United States. PATIENTS: 10689 patients with chest pain or other symptoms suggestive of acute cardiac ischemia. INTERVENTION: The probability of acute ischemia predicted by the acute cardiac ischemia time-insensitive predictive instrument (ACI-TIPI), either automatically printed or not printed on patients' electrocardiograms. MEASUREMENTS: Emergency department triage to a coronary care unit (CCU), telemetry unit, ward, or home. Other measurements were the bed capacity of the CCU relative to that of the telemetry unit; training or supervision status of the triaging physician; and patient diagnoses and outcomes based on clinical, electrocardiographic, and creatine kinase data. RESULTS: For patients without cardiac ischemia, in hospitals with high-capacity CCUs and relatively low-capacity cardiac telemetry units, use of ACI-TIPI was associated with a reduction in CCU admissions from 15% to 12%, a change of -16% (95% CI, -30% to 0%), and an increase in emergency department discharges to home from 49% to 52%, a change of 6% (CI, 0% to 14%; overall P=0.09). Across all hospitals, for patients evaluated by unsupervised residents, use of ACI-TIPI was associated with a reduction in CCU admissions from 14% to 10%, a change of -32% (CI, -55% to 3%); a reduction in telemetry unit admissions from 39% to 31%, a change of -20% (CI, -34% to -2%); and an increase in discharges to home from 45% to 56%, a change of 25% (CI, 8% to 45%; overall P=0.008). Among patients with stable angina, in hospitals with high-capacity CCUs, use of ACI-TIPI was associated with a reduction in CCU admissions from 26% to 13%, a change of -50% (CI, -70% to -17%), and an increase in discharges to home from 20% to 22%, a change of 10% (CI, -29% to 71%; overall P=0.02). At hospitals with high-capacity telemetry units, use of ACI-TIPI was associated with a reduction in telemetry unit admissions from 68% to 59%, a change of -14% (CI, -27% to 1%), and an increase in emergency department discharges to home from 10% to 21%, a change of 100% (CI, 22% to 230%; overall P=0.02). Among patients with acute myocardial infarction or unstable angina, use of ACI-TIPI did not change appropriate admission (96%) to the CCU or telemetry unit at hospitals with high-capacity CCUs or telemetry units. CONCLUSIONS: Use of ACI-TIPI was associated with reduced hospitalization among emergency department patients without acute cardiac ischemia. This result varied as expected according to the CCU and cardiac telemetry unit capacities and physician supervision at individual hospitals. Appropriate admission for unstable angina or acute infarction was not affected. If ACI-TIPI is used widely in the United States, its potential incremental impact may be more than 200000 fewer unnecessary hospitalizations and more than 100000 fewer unnecessary CCU admissions. 相似文献
75.
WB van den Berg 《Canadian Metallurgical Quarterly》1998,20(1-2):149-164
Chronic arthritis is characterized by a persistent joint inflammation and concomitant joint destruction. Although the joint swelling is a major clinical problem, destruction of bone and cartilage may occur uncoupled to inflammation and it is of utmost importance to fully understand the elements of the destructive process. TNF and IL-1 are considered master cytokines in the process of human RA, with a claimed cascade of TNF inducing most of the IL-1 production. Studies in experimental models revealed that TNF is indeed a pivotal cytokine in joint swelling, yet IL-1 is the dominant cartilage destructive cytokine and its production may occur independent of TNF. This was found with anti-TNF/IL-1 neutralizing antibodies and the observations were recently backed up with similar data in arthritis models in TNF and IL-1 knockout mice. Apart from the absolute level of IL-1, the destructive potential of an arthritis is determined by the balance with regulatory cytokines and anabolic growth factors. IL-4, IL-6, and IL-10 can promote inflammation and tissue fibrosis, yet cartilage destruction is found to be greatly reduced by these cytokines, linked to a range of pathways which can reduce the IL-1 impact on the articular cartilage. Finally, the presence of anabolic growth factors in the inflamed synovium may have a major impact on net destruction. Endogenous transforming growth factor-beta (TGF-beta) is found in inflamed synovia, but local coadministration of TGF-beta further enhanced the degree of synovitis, yet almost fully prevented cartilage damage, providing another example of a major lack of correlation between inflammatory mass and destructive potential. It is suggested that novel therapy in RA patients should not only focus on reduction of outer signs of joint inflammation, but should also include attempts at reduction of cartilage destruction. 相似文献
76.
77.
PURPOSE: To assess the impact of assisted hatching on in vitro fertilization (IVF) outcome in women age 40 and older. METHODS: A retrospective analysis was performed to compare 28 cycles of IVF without assisted hatching to 38 cycles of IVF with assisted hatching. All patients in both groups were age 40 or older and the mean age was similar. RESULTS: The delivery rate per oocyte retrieval was significantly higher in the assisted hatching group (18/38; 48%) compared to the nonhatched controls (3/28; 11%, P = 0.0003). The implantation rate of hatched embryos (40/175; 22%) was clearly enhanced, compared to the nonhatched embryos (7/126; 6%, P < 0.001). The fertilization rate, number of oocytes and the number of embryos per patient were comparable in the two groups. CONCLUSIONS: Assisted hatching dramatically improves embryonic implantation and term pregnancy rates in women age 40 and older undergoing IVF. 相似文献
78.
CL Cosma PN Danese JH Carlson TJ Silhavy WB Snyder 《Canadian Metallurgical Quarterly》1995,18(3):491-505
Anticipation and suspicion are critical aspects to any discussion of intrauterine adhesions. Curettage between the second and fourth week postpartum is more likely to cause adhesions than is any other endometrial trauma. Infertility, recurrent abortion, or menstrual aberrations after any uterine trauma should cause the physician to suspect the presence of intrauterine adhesions. Hysterosalpingography and hysteroscopy are the ideal methods to make the diagnosis of IUA, and the latter is the safest, least traumatic, and most precise method of treating adhesions. The addition of an intrauterine splint and high-dose estrogen therapy completes the therapeutic approach. Before attempting conception the cavity should be inspected to verify its normality. 相似文献
79.
80.
gamma-Aminobutyric acid type C (GABAC) receptors identified in retina appear to be composed of GABA rho subunits. The purpose of this study was to localize signals for homooligomeric assembly of rho1 subunits and to investigate whether the same region contained signals for heterooligomeric interaction with rho2 subunits. In vitro translated human rho1 was shown to be membrane-associated, and proteinase K susceptibility studies indicated that the N terminus was oriented in the lumen of ER-derived microsomal vesicles. This orientation suggested the involvement of the N terminus of rho1 in the initial steps of subunit assembly. To test this hypothesis, mutants were created containing only N-terminal sequences (N-rho1) or C-terminal sequences (C-rho1) of rho1. Co-immunoprecipitation studies revealed that N-rho1, but not C-rho1, interacted with rho1 in vitro. When coexpressed in Xenopus oocytes, N-rho1 interfered with rho1 receptor formation. Together, these data suggested that signals for rho1 homooligomeric assembly reside in the N-terminal half of the subunit. Sequential immunoprecipitations were then performed upon cotranslated rho1 and rho2 subunits which demonstrated that rho1 and rho2 interacted in vitro. Co-immunoprecipitation indicated that N-rho1 specifically associated with rho2. Therefore, the N-terminal regions of rho subunits contain the initial signals for both homooligomeric and heterooligomeric assembly into receptors with GABAC properties. 相似文献