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91.
OBJECTIVE: Increased intra-abdominal pressure (IAP) compromises cardiopulmonary function and visceral perfusion. Our goal was to characterize acute changes in these subsystems associated with operative abdominal decompression. PATIENT POPULATION: A series of 11 consecutive injured patients monitored with a pulmonary artery catheter and nasogastric tonometer in whom operative decompression was performed. Indications for decompression included oliguria or progressive acidosis despite aggressive resuscitation in the presence of elevated IAP (>25 mm Hg). MAIN OUTCOME MEASURES: Studied hemodynamic variables included pulmonary artery occlusion pressure (PAOP), right ventricular end-diastolic volume index (RVEDVI), and cardiac index (CI). Pulmonary variables included shunt fraction (Qs/Qt) and dynamic compliance (Cdyn). Visceral perfusion was assessed using hourly urine output 4 hours before and after decompression (UOP) and gastric intramucosal pH (pHi). Mean values before and after decompression were compared using the paired t test. Linear regression and Fisher's z transformation were used to evaluate the relationships between RVEDVI, PAOP, CI, and IAP. IAP was transduced via bladder pressures. Significance was defined as p < 0.05. Data are expressed as means+/-SD. RESULTS: IAP decreased with decompression (49+/-11 to 19+/-6.8 mm Hg; p < 0.0001). RVEDVI improved independent of CI and correlated better (p < 0.01) with CI (r =0.49, p=0.04) than PAOP did (r=-0.36, p=0.09). PAOP correlated significantly with IAP (r=0.45, p=0.04). Decompression resulted in significant improvements in Qs/Qt, Cdyn, UOP, and pHi. CONCLUSION: Abdominal decompression in patients with increased IAP improves preload, pulmonary function, and visceral perfusion. Elevated IAP has important effects on PAOP, which makes the PAOP an unreliable index of preload in these patients.  相似文献   
92.
PURPOSE: To compare standard therapy with bleomycin, etoposide, and cisplatin (BEP) to experimental therapy with etoposide, ifosfamide, and cisplatin (VIP) as primary treatment of men with advanced, disseminated germ cell tumors. PATIENTS AND METHODS: A total of 304 men with advanced disseminated germ cell tumors were randomly allocated to receive four courses of BEP or VIP. Two hundred ninety-nine patients were assessable for toxicity and 286 were assessable for response. Complete response rates, favorable response (complete remission, surgical free of disease, continuous partial remission for 2+ years), time to treatment failure, and overall survival were assessed. RESULTS: Overall complete remission rate (VIP, 37%; BEP, 31%), favorable response rate (VIP, 63%; BEP, 60%), failure-free at 2 years (VIP, 64%; BEP, 60%), and 2-year overall survival (VIP, 74%; BEP, 71%) were not significantly different between the two treatments. Grade 3 or worse toxicity, particularly hematologic and genitourinary toxicity, was significantly more common in patients who received VIP. CONCLUSION: BEP and VIP produce comparable favorable response rate and survival in patients with poor-risk germ cell tumors. The substitution of ifosfamide for bleomycin, however, was associated with significantly greater toxicity. Four courses of BEP remain the standard treatment for advanced disseminated germ cell tumors.  相似文献   
93.
OBJECTIVE: Right-angle dual-headed tomography has increased cardiac SPECT utility by cutting acquisition time in half which enhances gating capabilities. When gating, however, a deceleration in heart rate, due to a return to baseline rate after stress or lessened anxiety at the end of a study, may significantly affect the last step(s) of a gated study with possible frame or information loss. The purpose of this study was to illustrate the artifacts produced in myocardial perfusion studies when a frame or frames are lost in single- and dual-detector SPECT imaging methodologies. METHODS: A near-normal 99mTc-sestamibi study was obtained using a dual-headed camera system fitted with high-resolution, long-bore collimators. The normal study was processed including all frames (1-32). To demonstrate the effect of losing frames on a dual-headed system, the study was processed three different ways to simulate frame loss. RESULTS: Loss of frames at the end of a SPECT acquisition results in significant inferoseptal wall defects, left ventricular lumen narrowing, as well as thinning of the anterior and lateral walls. The overall appearance of the heart is a more oval-shaped heart with decreased perfusion. The effect of losing the last frame in a dual-headed camera system as opposed to losing the last frame in a single-headed camera system is more substantial. CONCLUSION: A scan resulting in the loss of a frame in either a single- or a dual-headed camera system creates artifacts in the myocardial wall and should always be repeated. It is significant to note that artifacts present in a dual-headed system are much more prevalent than in a single-headed system due to the nature of dual-headed acquisition parameters.  相似文献   
94.
We have evaluated our practice of tube caecostomies in 21 children operated on from January 1982 to December 1987 at the Royal Hospital for sick children, Bristol, and 18 children operated on at the Paediatric Surgery Unit of the Korle-Bu Teaching Hospital, Accra, Ghana from January 1989 to December 1996. The indications for surgery were, Hirschsprung's disease (36) and idiopathic constipation (3). The definitive procedures involved were Duhamel's procedure in 36, Soave's procedure in 2 and colo-anal anastomosis in 1 case. This method reduces the total number of surgical operations required by the child from 3 to 2, thereby reducing the total period of hospitalisation for the child. A sample technique of tube caecostomy is described in 39 children undergoing corrective surgery.  相似文献   
95.
The hypothesis that heparin-coated perfusion circuits reduce thrombin formation and activity; fibrinolysis; and platelet, complement, and neutrophil activation was tested in 20 consecutive, randomized adults who had cardiopulmonary bypass. Twenty identical perfusion systems were used; in 10, all blood-contacting surfaces were coated with partially degraded heparin (Carmeda process; Medtronic Cardiopulmonary, Anaheim, Calif.). All patients received a 300 U/kg dose of heparin. Activated clotting times were maintained longer than 400 seconds. Cardiopulmonary bypass lasted 36 to 244 minutes. Blood samples for platelet count, platelet response to adenosine diphosphate, plasma beta-thromboglobulin, inactivated complement 3b, neutrophil elastase, fibrinopeptide A, prothrombin fragment F1.2, thrombin-antithrombin complex, tissue plasminogen activator, plasminogen activator inhibitor-1, plasmin alpha 2-antiplasmin complex, and D-dimer were obtained at these times: after heparin was given, 5 and 30 minutes after cardiopulmonary bypass was started, within 5 minutes after bypass was stopped, and 15 minutes after protamine was given. After cardiopulmonary bypass, tubing segments were analyzed for surface-adsorbed anti-thrombin, fibrinogen, factor XII, and von Willebrand factor by radioimmunoassay. Heparin-coated circuits significantly (p < 0.001) reduced platelet adhesion and maintained platelet sensitivity to adenosine diphosphate (p = 0.015), but did not reduce release of beta-thromboglobulin. There were no significant differences between groups at any time for fibrinopeptide A, prothrombin fragment F1.2, or thrombin-antithrombin complex or in the markers for fibrinolysis: D-dimer, tissue plasminogen activator, plasminogen activator inhibitor-1, and alpha 2-antiplasmin complex. In both groups, concentrations of prothrombin fragment F1.2 and thrombin-antithrombin complex increased progressively and significantly during cardiopulmonary bypass and after protamine was given. Concentrations of D-dimer, alpha 2-antiplasmin complex, and plasminogen activator inhibitor-1 also increased significantly during bypass in both groups. Fibrinopeptide A levels did not increase during bypass but in both groups increased significantly after protamine was given. No significant differences were observed between groups for levels of inactivated complement 3b or neutrophil elastase. Radioimmunoassay showed a significant increase in surface-adsorbed antithrombin on coated circuits but no significant differences between groups for other proteins. We conclude that heparin-coated circuits used with standard doses of systemic heparin reduce platelet adhesion and improve platelet function but do not produce a meaningful anticoagulant effect during clinical cardiopulmonary bypass. The data do not support the practice of reducing systemic heparin doses during cardiac operations with heparin-coated extracorporeal perfusion circuitry.  相似文献   
96.
OBJECTIVES: This study investigated the efficacy of a social-influences tobacco prevention program conducted with adolescents living in a high tobacco production area. METHODS: Students in 10 experimental schools completed the tobacco prevention program and a booster intervention. Control students received health education as usual. RESULTS: After 2 years of treatment, smoking rates in the treatment group (vs the control group) were lower for 30-day, 7-day, and 24-hour smoking. The intervention had more of an impact on those who were involved in raising tobacco than it did on those not involved in raising tobacco. CONCLUSIONS: Although modest, effects were achieved with minimal intervention time in a high-risk group, indicating that social-influences prevention programs may be effective in such groups.  相似文献   
97.
Cysteine string proteins (Csps) are synaptic vesicle proteins thought to be involved in calcium-dependent neurotransmitter release at nerve endings. Here, we report the cloning of two Csp variants, termed Csp1 and Csp2, from bovine adrenal medullary chromaffin cells. The bovine Csp1 appears to be the homologue of rat brain Csp, sharing 95% identity at the amino acid level. The nucleotide sequence of csp2 is identical with that of csp1 except for a 72-base insert which introduces a stop codon into the coding sequence, which would be predicted to result in a truncated protein 3.3 kDa smaller than Csp1. Furthermore, polymerase chain reaction analysis detected homologues of Csp1 and Csp2 in rat kidney, liver, pancreas, spleen, lung, and adrenal gland. Expression of Csps in non-neuronal tissues was confirmed by Northern blotting and by immunoblotting with anti-Csp1 antiserum which also demonstrated expression of both full-length and truncated Csps in spleen. The widespread tissue distribution is inconsistent with a role of Csps as specific regulators of presynaptic calcium channels as previously proposed. We suggest that Csps may have a more general role in membrane traffic in non-neuronal as well as neuronal cells.  相似文献   
98.
The term, atrophy/hypertrophy complex (AHC) of the liver, denotes a distinct combination of hepatic atrophy and hypertrophy occurring in situations of significant impairment of bile flow and/or portal or hepatic venous blood flow. In the lobes or segments concerned atrophy ensues, whereas areas not or less involved develop compensatory hypertrophy, resulting in a characteristic gross deformity of the organ and, in some instances, in rotation of the liver around a virtual hilar axis. As recognition and early detection of AHC have a strong implication on the treatment of several hepatobiliary diseases, adequate combined clinical, radiological and histopathological strategies have to be used in order to arrive at a correct diagnosis. The present investigation was designed to analyze the morphology of AHC in detail and to define lesion patterns having the highest predictive value. For atrophy, the following features were highly characteristic: 1) Advanced septal fibrosis with or without nodular change of parenchyma; 2) Biliary piecemeal necrosis with formation of vascular structures; 3) Ductular proliferations, frequently extending into septa and involving the parenchyma; 4) Capillarization of sinusoids with type IV collagen deposition in Disse's space; 5) Factor VIII-associated antigen expression by sinusoidal endothelia; 6) a seemingly paradoxical increase of proliferative activity of hepatocytes as based on PCNA staining. The severity of lesions in atrophy was related to the type of underlying disease, in that the changes were clearly more expressed in situations of longstanding obstruction due to benign disease. Using a set of well-defined morphological parameters, atrophy can be reproducibly distinguished from hypertrophy in biopsy material from AHC.  相似文献   
99.
BACKGROUND: Exercise testing is useful in the assessment of symptomatic patients for diagnosis of significant or extensive coronary disease and to predict their future risk of cardiac events. The Duke treadmill score (DTS) is a composite index that was designed to provide survival estimates based on results from the exercise test, including ST-segment depression, chest pain, and exercise duration. However, its usefulness for providing diagnostic estimates has yet to be determined. METHODS AND RESULTS: A logistic regression model was used to predict significant (>/=75% stenosis) and severe (3-vessel or left main) coronary artery disease, and a Cox regression analysis was used to predict cardiac survival. After adjustment for baseline clinical risk, the DTS was effectively diagnostic for significant (P<0.0001) and severe (P<0.0001) coronary artery disease. For low-risk patients (score >/=+5), 60% had no coronary stenosis >/=75% and 16% had single-vessel >/=75% stenosis. By comparison, 74% of high-risk patients (score <-11) had 3-vessel or left main coronary disease. Five-year mortality was 3%, 10%, and 35% for low-, moderate-, and high-risk DTS groups (P<0.0001). CONCLUSIONS: The composite DTS provides accurate diagnostic and prognostic information for the evaluation of symptomatic patients evaluated for clinically suspected ischemic heart disease.  相似文献   
100.
Ly-49D is an activating receptor on NK cells that does not become tyrosine phosphorylated upon activation. This report demonstrates that immunoprecipitation of Ly-49D, following pervanadate treatment or specific Ab cross-linking, coprecipitates a 16-kDa tyrosine-phosphorylated protein (pp16). Immunoblotting experiments and data from TCR-zeta/Fc epsilonRIgamma double knockout mice confirm that pp16 is not TCR-zeta, TCR-eta, or Fc epsilonRIgamma. Association of pp16 with Ly-49D involves a transmembrane arginine since mutation to leucine (Ly-49D[R54L]) abolishes association with pp16 in transfected P815 cells. In addition, Ly-49D(R54L) transfectants fail to mediate Ca2+ mobilization following Ab cross-linking. Therefore, signaling through Ly49D on NK cells depends on association with a distinct tyrosine phosphoprotein (pp16) in a manner analogous to that of TCR and FcR. Expression of this novel signaling peptide in both the NK and myeloid lineages indicates that pp16 is likely involved in the signal transduction cascade of additional receptor families.  相似文献   
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