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41.
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In normal coronary arteries, reactive hyperemic responses to a 20-second occlusion, an index of coronary reserve, usually demonstrate a peak-to-resting flow velocity ratio of 4:1 or more. Most intraoperative studies that have assessed reactive hyperemic responses in bypassed vessels have reported peak-to-resting flow velocity ratios of 2:1 or less following a 20-second occlusion. These decreased reactive hyperemic responses could be due to coronary vasodilatation after cardiopulmonary bypass or to an inadequate physiological result of the surgical procedure. In 14 patients with angiographically normal coronary arteries, the peak-to-resting flow velocity ratio following a 20-second coronary occlusion decreased significantly (p less than 0.05) from 4.4 +/- 0.2 (mean +/- standard error) before bypass to 3.0 +/- 0.3 after bypass. In a similar dog model, the peak-to-resting flow velocity ratio decreased by 36 to 52% during the first hour following one hour of cardiopulmonary bypass and cardioplegia. During the same period, left ventricular perfusion increased 21 to 30%, mean arterial pressure and coronary vascular resistance decreased, and myocardial oxygen consumption was unchanged. In a second group of dogs studied for the effects of duration (200 to 240 minutes) of anesthesia and thoracotomy alone, peak-to-resting flow velocity ratio was significantly lower. These clinical and experimental studies suggest that major coronary vasodilatation occurs early following cardiopulmonary bypass and cold cardioplegia, and may contribute to the blunted coronary reactive hyperemic responses reported during this time. Consequently, an intraoperative peak-to-resting flow velocity ratio of 3:1 for bypassed coronary arteries may represent an excellent physiological result.  相似文献   
43.
Fifty patients with refractory acute lymphoblastic leukemia underwent allogeneic bone marrow transplantation after conditioning with high-dose cytosine arabinoside and fractionated total body irradiation. Twenty-nine received intravenous immunoglobulin (i.v.Ig) infusion, primarily to prevent cytomegalovirus infection, and 21 did not. The two groups were biologically comparable. Seven (24.5%) of the i.v.Ig-treated and 14 (66.7%) of the non-i.v.Ig-treated patients developed systemic viral, fungal or bacterial infections and/or interstitial pneumonitis (p less than 0.005), which were fatal in three and 12 cases respectively (p less than 0.001). Currently, 23 (79.3%) of the 29 i.v.Ig-treated and eight (38.1%) of the 21 non-i.v.Ig-treated patients are alive and well (p less than 0.01). We conclude that prophylactic i.v.Ig infusions may reduce the frequency of all forms of serious infection in patients with acute lymphoblastic leukemia undergoing allogeneic marrow transplantation, and thereby improve their survival expectation.  相似文献   
44.
BACKGROUND: In chronic ambulatory peritoneal dialysis, bicarbonate-buffered fluids, with their neutral pH and less advanced glycosylation end-products (AGE) and glucose degradation products (GDP), have better biocompatibility than conventional peritoneal dialysis (PD) solutions. That difference may be more beneficial in automated peritoneal dialysis (APD), due to its more frequent exchanges and longer contact times with fresh dialysate. We performed a prospective, randomized study in APD patients to compare the biocompatibility of conventional and bicarbonate/lactate-buffered PD fluids. METHODS: We randomized 14 APD patients to have APD with either conventional or bicarbonate/lactate-based fluids. After 6 months, both groups changed to the other solution. The overall observation period was 12 months. After 1 and 5 months and again after 7 and 11 months, phagocytotic and respiratory burst capacities of effluent peritoneal macrophages were determined. Plasma interleukin (IL)-6 and C-reactive protein (CRP) as well as effluent IL-6, CRP, transforming growth factor (TGF)-beta 1, AGE and CA125 concentrations were measured. Inflow pain was quantified using a patient questionnaire. RESULTS: Respiratory burst capacity remained unchanged and phagocytotic activity increased significantly during APD (P<0.001) with the bicarbonate/lactate fluid. Effluent IL-6 release was significantly lower than with the lactate fluid (P<0.05). While in the effluent TGF-beta 1 was unaffected, AGE concentration was lower after bicarbonate/lactate treatment (P<0.05). Effluent CA125 concentration, an indicator of mesothelial cell integrity, was higher (P<0.05) in neutral effluents. Finally, patients' inflow pain diminished (P = 0.05) when using the neutral fluid. CONCLUSIONS: The use of a neutral PD fluid in APD improved patients' inflow pain as well as biocompatibility parameters reflecting enhanced phagocytotic activity of peritoneal macrophages, reduced constitutive inflammatory stimulation (IL-6), reduced AGE accumulation in the peritoneal cavity and better preservation of the mesothelial cell integrity. From the biocompatibility point of view, a neutral fluid with low GDP content can be recommended as the primary choice for APD.  相似文献   
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The purpose of this study was to clarify the issue of whether DSM-III-R (American Psychological Association [APA], 1987) over-or underdiagnoses autism by comparing this diagnostic system to a well-established objective measure of diagnosis, the Childhood Autism Rating Scale (CARS). A secondary goal was to determine which of the 16 criteria are the best discriminators of autism. DSM-III-R, CARS, and clinical diagnoses of 138 consecutive admissions to a statewide program for the diagnosis and treatment of autistic and related communication-handicapped individuals (Division TEACCH in North Carolina) were compared. Results indicated a generally high degree of agreement on the diagnosis of autism using the three systems. Within this tratment-oriented program, the CARS and clinical ratings diagnosed a greater number of cases as autistic than did the DSM-III-R criteria, suggesting that DSM-III-R slightly underdiagnosed autism. The criteria that most strongly related to the diagnosis of autism regardless of the system were lack of awareness of others, abnormal social play, an impaired ability to make friends, abnormal nonverbal communication, stereotypic body movements, and restricted range of interests.  相似文献   
47.
Twenty-nine New Zealand white rabbits were allocated to undergo insertion of either polytetrafluoroethylene (PTFE) (n = 22) or microporous silicone rubber (SR) (n = 7), 3-mm diameter, 10-mm long aortic grafts. Animals with PTFE grafts received aspirin (ASA) 10 mg/kg/d and dipyridamole (DPM) 10 mg/kg/d (n = 11) or placebo (n = 11). Autologous In-111-oxine-labeled platelets were reinfused on reestablishment of blood flow through the graft. Using gamma camera images, an external graft platelet accumulation index (E-GPAI) was calculated as the In-111 activity in the graft area to the reference aorta at 24, 48, and 72 hours post implantation. Mean E-GPAI +/- SEM values for the ASA/DPM (n = 4) and control groups (n = 7) were 1.13 +/- 0.16 and 1.34 +/- 0.05 (NS) at 24 hours, 1.20 +/- 0.16 and 1.33 +/- 0.07 (NS) at 48 hours, and 1.38 +/- 0.07 and 1.35 +/- 0.10 (NS) at 72 hours, respectively. A similar internal graft platelet accumulation index (I-GPAI) was constructed based on In-111 activity in excised grafts and reference aorta measured in a scintillation counter. Mean I-GPAI +/- SEM values for the PTFE ASA/DPM (n = 9) and control groups (n = 8) at 48 hours post implantation were 43.1 +/- 2.7 and 216.8 +/- 73.9 (P = 0.05), respectively. I-GPAI values for the SR grafts were 192.5 +/- 43.1. Conclusion: The E-GPAI was not sensitive enough to demonstrate the effect of antiplatelet medication on platelet accumulation on the PTFE grafts.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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49.
Human seminal plasma from normal or patients with abnormal parameters of the ejaculates contains an inhibitory material that expresses potent in vitro inhibitory activity on PHA-M-induced blast transformation and NK activity. Using the test of inhibition of NK activity, the semen samples from individuals with higher concentrations of fructose had higher inhibitory activity. The results described herein suggest that inhibitory activity for blast transformation may be present in the prostatic fluid while the NK inhibition aspects are correlated with the vesicle-marker (fructose). Inhibition of the immune responses by human seminal plasma of the effector functions indicates the interesting implication that soluble factors may indirectly protect against or promote human autoimmune infertility disease.  相似文献   
50.
BACKGROUND: Cancer pain is highly prevalent and commonly undertreated. This study was designed to determine whether dissemination of a clinical protocol for pain management would improve outcomes in community oncology practices. PATIENTS AND METHODS: A pain management protocol was developed based on accepted guidelines. After baseline assessment, oncology practices were randomly assigned to 'analgesic protocol' (AP) sites, where oncologists implemented the guidelines in a group of lung or prostate cancer patients, or to 'physician discretion' (PD) sites, where customary treatment was continued. Patients treated on protocol and a comparison group of patients with pain due to breast cancer or myeloma were monitored for change in pain using the Brief Pain Inventory, and for change in other symptoms or mood. RESULTS: The protocol terminated early because of poor accrual. We compared groups using proportions of patients who had no or mild pain at follow-up. Although measures of protocol adherence did not suggest the occurrence of major practice change, the proportion of lung or prostate cancer patients with no or mild pain increased significantly from baseline for those treated at AP sites compared with those treated at PD sites. There was no significant difference between the breast and myeloma patients treated at AP sites versus those treated at PD sites. CONCLUSION: A protocol for cancer pain management can improve pain control. Diffusion of these benefits to other patients was not confirmed. Given the small sample size, these findings require confirmation in a larger trial.  相似文献   
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