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71.
Protective capacity of polyclonal and monoclonal antibodies directed against endotoxin during experimental sepsis 总被引:1,自引:0,他引:1
Both monoclonal antibody (MAb) and polyclonal antibody (PAb) directed against the shared core/lipid A region of lipopolysaccharide (LPS) (endotoxin) provide protection during experimental gram-negative bacterial sepsis. Although these preparations have not been compared, clinical trials administering either preparation to septic patients have been instituted. The core/lipid A region of LPS represents an antigenic domain common to many, if not all, gram-negative microbes, and thus represents an ideal target site for antibody binding. We sought to determine (1) the protective capacity of similarly reactive IgG anti-core LPS/lipid A MAbs and PAbs, (2) whether the timing of administration was important, and (3) whether either would act additively with antimicrobial agents. Antibody was administered intravenously to outbred mice, and Escherichia coli 0111:B4 was then administered intravenously or intraperitoneally with hemoglobin. Monoclonal antibodies and PAbs were equally protective, and protection was maximized by pretreatment, although the effect extended to four hours after bacterial challenge. Both MAbs and PAbs acted in concert with gentamicin hydrochloride to further reduce lethality. We concluded that MAbs and PAbs were equally protective and that clinical utility may eventually be dictated by ease and cost of antibody production. 相似文献
72.
Kenneth J. Sher PhD Arthur I. Alterman PhD 《Alcoholism, clinical and experimental research》1988,12(2):233-238
Although Tarter et al.'s (1977) HK/MBD questionnaire has been found useful in subtyping populations of clinical alcoholics, its potential utility in nonclinical populations has yet to be determined. The current study examined the family history, personality, and substance use/abuse correlates of Tarter et al.'s HK/MBD questionnaire and factor analytically derived subscales (Alterman and McLellan, 1986) in a nonclinical sample of 580 young, adult males. In addition, a factor analysis of the HK/MBD questionnaire was undertaken to assess the extent to which the factor structure determined on a clinical alcoholic sample replicates in a nonclinical sample. Results indicated that each of the HK/MBD subscales showed relatively unique patterns of correlations with the various personality measures employed suggesting that they are measuring separate constructs. Perhaps of greatest importance, the HK/MBD items that appear to be of greatest relevance for understanding substance use/abuse are those related to antisocial behavior. Finally, the factor structure of the HK/MBD questionnaire in the nonclinical sample was found to be quite similar to the structure obtained in a clinical sample. These results demonstrate the multidimensional structure of the HK/MBD questionnaire and the utility of using the more homogeneous subscales in research with both clinical and nonclinical samples. 相似文献
73.
Scott L. Nyberg Arthur J. Matas Walter K. Kremers Jeffrey D. Thostenson Timothy S. Larson Mikel Prieto Michael B. Ishitani Sylvester Sterioff Mark D. Stegall 《American journal of transplantation》2003,3(6):715-721
We previously proposed a quantitative approach to assess donor organs for cadaver renal transplantation. To improve on our original scoring system, we studied 34 324 patients who received cadaver renal transplants from adult donors between 1994 and 1999 and were reported to the UNOS Scientific Renal Transplant Registry. A scoring system was developed from five donor variables (age, 0-25 points; history of hypertension, 0-4; creatinine clearance before procurement, 0-4; cause of death, 0-3; HLA mismatch, 0-3) that showed a significant correlation with renal function and long-term graft survival. Cadaver kidneys were stratified by cumulative donor score: grade A, 0-9 points; grade B, 10-19; grade C, 20-29; and grade D, 30-39. The influence of donor score on renal function and graft survival was most severe above 20 points, designated 'marginal' kidneys. In summary, a donor scoring system developed from a large population database was useful in predicting outcome after cadaver renal transplantation. The improved system provides a quantitative approach to evaluation of marginal kidneys and may improve allocation of these organs in cadaver renal transplantation. 相似文献
74.
OBJECTIVE: The aim of the present study was to examine the nature of previously reported deficits in sustained attention and response inhibition in adults with the developmental disorder, phenylketonuria (PKU). METHODS: This study used event-related potentials (ERPs) to examine the performance of PKU adults (n=9) and a matched control group (n=9) on a visual Go-Nogo task. RESULTS: Comparison of behavioural measures between the PKU and control groups failed to reach statistical significance, yet analysis of the ERPs showed statistically significant amplitude reductions in the P1 and N1 components elicited following presentation of stimuli, and a reduction in the amplitude of the N2 component elicited following presentation of Nogo stimuli. CONCLUSIONS: These results suggest that adults with PKU, despite being continuously treated from birth, manifest subtle impairments in distinct aspects of information processing including early sensory processing of visually presented information, as well as impairments in inhibitory functions. SIGNIFICANCE: The results contribute to an understanding of the neurophysiological mechanisms that are implicated in PKU and highlight the sensitivity of ERP techniques for the identification of the loci of information processing deficits in clinical groups. 相似文献
75.
Mitchell S. Cappell M.D. Ph.D. Arthur J. Geller M.D. 《The American journal of gastroenterology》1992,87(7):815-824
The patterns of which human immunodeficiency virus (HIV)-seropositive patients underwent endoscopy for gastrointestinal bleeding at a university hospital were analyzed in 50 consecutive patients admitted from July 1984 through December 1989, and criteria were developed as to which patients are most likely to benefit from endoscopy. Analyzed patient data included the medical records, follow-up until July 1990 obtained by telephone questionnaire in 46 patients, and autopsy findings in the 11 patients undergoing autopsy. Thirty-seven percent of the patients did not undergo endoscopic or radiographic examinations indicated to determine the cause of bleeding. The adequacy of the evaluation was not related to race, intravenous drug abuse, homosexuality, hemophilia, the diagnosis of known AIDS, or being a public patient. In 21 of the 28 cases in which the cause of bleeding was determined, the diagnosed lesions had a specific, effective therapy. The mortality from gastrointestinal bleeding was 39.0%, compared with 8.3% in 48 controls without known HIV infection (p less than 0.001 by Fisher's exact test, odds ratio = 7.0, odds ratio confidence interval = 5.0-9.7). Statistically significant independent predictors of mortality included leukocytosis, concurrent major diseases, intravenous drug abuse, transfusion of 5 or more units of packed erythrocytes, and the presence of a bloody nasogastric aspirate or hematemesis (Wilk's lambda statistic = 0.369, p less than 0.0001). In particular, 10 of 11 patients (89%) with two or more concurrent major diseases died, whereas only three of 24 patients (13%) with no concurrent diseases died during the hospitalization. We conclude a large percentage of HIV-seropositive patients did not undergo a diagnostic evaluation for gastrointestinal bleeding at a university hospital, and there was no discernible rational pattern as to which patients underwent endoscopy. Endoscopy is an important and indicated procedure in HIV-seropositive patients with no or one concomitant major illness. HIV-seropositive patients with gastrointestinal bleeding and two or more concomitant major illnesses have an exceedingly poor prognosis, and are less likely to benefit from invasive diagnostic tests and aggressive therapy. 相似文献
76.
77.
We performed reconstruction of the anterior cruciate ligament in 33 patients using the central third of the patellar tendon. In 20 patients we did an arthroscopies! ly-assisted procedure, while 13 patients had an additional mini-arthrotomy through the gap in the patellar tendon. After 2-3 years the subjective knee function, according to the Lysholm score, was excellent or good in 18 knees and fair or poor in 15 knees, mainly due to anterior knee pain. Although 18 patients complained about anterior knee pain, only 1 patient required further surgery. After the operatio the patella had a lower position. A flexion contractur was found in 7 patients, and 13 had heterotopic bon formation at the apex of the patella. Although stabilit was restored in 31 of the 33 reconstructed knees anterior knee pain was a frequent complicatior There were no correlations between the anterior kne pain and patellar height, flexion contracture or hetei otopic bone formation. 相似文献
78.
D W Dunn 《Journal of child neurology》1988,3(3):167-173
Between August 1984 and September 1986, data were gathered prospectively on 114 episodes of convulsive status epilepticus, defined as seizure duration longer than 30 minutes, affecting 97 children. Status epilepticus was symptomatic in 72% (chronic 59%, acute 13%) and idiopathic or febrile in 28%. We identified precipitating factors in 63% of episodes. The most common factors were inadequate blood levels of anticonvulsants (32 of 60 episodes in children with prior seizures) and febrile illnesses, excluding meningitis or encephalitis (38 of 114 episodes). There was an elevated peripheral white blood cell count in 60%, acidosis with a pH of less than 7.0 in 12.5%, and cerebrospinal fluid pleocytosis not due to meningitis or encephalitis in 8 of 64 episodes. Eight children died, three with severe pre-existing brain damage, two with meningitis, and two with a poorly defined encephalopathy. Eighteen children developed a new neurologic deficit. Outcome was associated with the etiology and duration of status epilepticus, with age at the time of status a minor factor. A permanent deficit occurred in only five children with idiopathic or febrile status epilepticus. 相似文献
79.
We evaluated the effects of isoflurane anaesthesia and induced hypotension in 33 neurosurgical patients by electrocardiographic monitoring and serial cardiac enzyme measurements. An electrocardiogram (ECG) and serum enzymes were obtained preoperatively, intraoperatively and postoperatively in the recovery room and for three consecutive days. ECG leads II, V1 and V5 were monitored continuously during anaesthesia. Patients who had had a subarachnoid haemorrhage and a high incidence of abnormal preoperative ECG (42 per cent). Ten patients developed ECG changes intraoperatively, but these changes were unrelated to isoflurane-induced hypotension. Fifty-three per cent of patients developed an abnormal postoperative ECG. These abnormalities consisted mostly of nonspecific ST segment or T wave changes. At no time was there an elevation in cardiac enzyme activity. We found that nonspecific ECG changes are relatively common in patients undergoing vascular neurosurgical procedures. There was no enzymatic evidence of myocardial infarction and we can only speculate that these ECG changes are related to intracranial surgical manipulation. 相似文献
80.
C Joseph Muniz Arthur C Fleischer Edwin F Donnelly Murray J Mazer 《Journal of ultrasound in medicine》2002,21(2):129-133
OBJECTIVE: To assess the accuracy of three-dimensional color Doppler sonography and uterine artery arteriography in depicting changes in fibroid vascularity before and after embolization. METHODS: Preembolization and postembolization three-dimensional color Doppler sonography and selective uterine artery arteriography were retrospectively compared in 15 patients who underwent uterine artery embolization for treatment of symptomatic fibroids. Three-dimensional color Doppler sonography was performed by using a scanner with color power angiographic imaging capability. Vascularity was quantified by using an estimation of power-weighted pixel density as described by our group in previously published studies. Uterine artery arteriography was performed by using a standard selective microcatheter embolization technique. For purposes of comparison, fibroids were classified as either hypervascular or hypovascular relative to myometrial vascularity before and minutes to several hours after uterine artery embolization. Changes in fibroid vascularity (i.e., from hypervascular to hypovascular) as depicted by three-dimensional color Doppler sonography were compared with those shown on uterine artery arteriography and classified as being in agreement or disagreement. RESULTS: In 13 (87%) of 15 patients there was agreement; in 2 (13%) of 15 there was disagreement. In both cases of disagreement, three-dimensional color Doppler sonography showed collateral flow not depicted by uterine artery arteriography The mean reduction in quantitated vascularity after uterine artery embolization was 44% (range, 19%-78%). CONCLUSIONS: Three-dimensional color Doppler sonography accurately depicts fibroid vascularity and in some cases can reveal collateral flow not depicted by uterine artery arteriography. 相似文献