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V Falbo  T Pace  L Picci  E Pizzi    A Caprioli 《Infection and immunity》1993,61(11):4909-4914
Cytotoxic necrotizing factors (CNFs) are dermonecrotic protein toxins produced by human and animal clinical isolates of Escherichia coli. In this study, the CNF1 determinant was isolated and sequenced, showing that expression of biologically active toxin is governed by a unique open reading frame encoding a protein of 1,014 amino acids with a predicted molecular mass of 113.7 kDa. Nucleotide and protein data base searches showed significant homology between CNF1 and the dermonecrotic toxin of Pasteurella multocida. In particular, the two toxins were found to share a hydrophobic region of about 220 amino acids which is a potential membrane-spanning domain.  相似文献   
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Abdominal Radiology - To compare tumor detectability and conspicuity of standard b = 1000 s/mm2 (b1000) versus ultrahigh b = 2000 s/mm2 (b2000)...  相似文献   
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Prospective evaluation of posttransfusion hepatitis   总被引:1,自引:0,他引:1  
The incidence of posttransfusion hepatitis (PTH) was determined prospectively at our institution. An active surveillance program of transfused surgical patients was set up; alanine aminotransferase (ALT) levels were determined before transfusion and at monthly intervals for 6 months after transfusion. Patients with confirmed ALT values greater than 2.5 times the upper reference values were referred to the out-patient clinics for diagnosis. Of 4051 surgical patients who underwent transfusion between January 1986 and December 1989, 2459 (60.7%) were enrolled in the surveillance program, and 1018 (25.1%) completed the follow-up; 238 patients received autologous blood only and were used as controls. No PTH was observed in the control patients, and the incidence of the disease in patients receiving homologous blood was 10.97 percent in 1986, 6.58 percent in 1987, 5.55 percent in 1988, and 4.29 percent in 1989; the decreasing trend is significant (p = 0.018).  相似文献   
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Different patterns of 11q allelic losses in digestive endocrine tumors   总被引:5,自引:0,他引:5  
Most foregut digestive endocrine neoplasms may be associated with the multiple endocrine type 1 (MEN-1) syndrome. In contrast, midgut/hindgut carcinoids never show such association. To investigate the pathogenetic involvement of the MEN-1 gene and of putative additional oncosuppressor gene(s) distal to it, a comparative analysis of loss of heterozygosity (LOH) at chromosome 11q13 to 11qter was performed in 27 foregut (pancreatic endocrine tumors [PETs]), 23 midgut (ileal and appendiceal), and 3 hindgut (rectal) endocrine tumors. LOH at the MEN-1 gene locus at 11q13 was observed in 52% of the 23 sporadic and in all 4 MEN-1-associated PETs and was found to consistently and continuously span to the most distal marker investigated at 11qter. In contrast, only occasional, discontinuous, and mostly interstitial LOH for 11q markers was observed in ileal (midgut) carcinoids, whereas no LOH was found in all appendiceal (midgut) and rectal (hindgut) carcinoids. The consistent extension of LOH from the MEN-1 region to 11qter in sporadic PETs suggests a mechanism of gene inactivation via chromosomal breakage and complete loss of chromosome 11q; furthermore, these results expand beyond the 11q13 region the search for additional oncosuppressor gene(s) potentially involved in the genesis of these neoplasms. The low frequency, limited extension, and discontinuous distribution of 11q deletions in midgut/hindgut carcinoids suggest that MEN-1 gene is not involved in the pathogenesis of these tumors.  相似文献   
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Prolactin levels are elevated significantly during the recovery process from surgical insult, implying a role for prolactin in the neuroendocrine immune network. This study examined the importance of severity of surgical insult to the prolactin response. Two groups of surgical patients were chosen consecutively and studied prospectively. Seven patients scheduled for "clean" elective surgery, i.e., herniorrhaphy and laparoscopic cholecystectomy, were compared with seven patients scheduled for prolonged abdominal exploration. Blood was drawn for prolactin and cortisol at 8:00 AM on the day of surgery and on postoperative days one, three, and five. Using a two-tailed test, preoperative prolactin levels and levels on postoperative days three and five were significantly different in the prolonged surgery group (.012 and .002, respectively). There were no statistically significant differences in preoperative and postoperative prolactin levels in the clean surgery group. Cortisol levels were not significantly elevated in either group. These results indicate that the prolactin response to surgery is related to the severity of the surgical insult.  相似文献   
28.
A review of health-related workplace productivity loss instruments   总被引:3,自引:0,他引:3  
The objective of this review was to identify health-related workplace productivity loss survey instruments, with particular emphasis on those that capture a metric suitable for direct translation into a monetary figure. A literature search using Medline, HealthSTAR, PsycINFO and Econlit databases between 1966 and 2002, and a telephone-administered survey of business leaders and researchers, were conducted to identify health-related workplace productivity measurement survey instruments. This review was conducted from the societal perspective. Each identified instrument was reviewed for the following: (i). reliability; (ii). content validity; (iii). construct validity; (iv). criterion validity; (v). productivity metric(s); (vi). instrument scoring technique; (vii). suitability for direct translation into a monetary figure; (viii). number of items; (ix). mode(s) of administration; and (x). disease state(s) in which it had been tested. Reliability and validity testing have been performed for 8 of the 11 identified surveys. Of the 11 instruments identified, six captured metrics that are suitable for direct translation into a monetary figure. Of those six, one instrument measured absenteeism, while the other five measured both absenteeism and presenteeism. All of the identified instruments except for one were available as paper, self-administered questionnaires and many were available in languages other than English. This review provides a comprehensive overview of the published, peer-reviewed survey instruments available to measure health-related workplace productivity loss. As the field of productivity measurement matures, tools may be developed that will allow researchers to accurately calculate lost productivity costs when performing cost-effectiveness and cost-benefit analyses. Using data captured by these instruments, society and healthcare decision makers will be able to make better informed decisions concerning the value of the medications, disease management and health promotion programmes that individuals receive.  相似文献   
29.
Dyspnoea is not a prominent complaint of resting patients with recent hemispheric stroke (RHS). We hypothesized that, in patients with RHS presenting abnormalities in respiratory mechanics, increased respiratory motor output could translate into an increased perception of dyspnoea. We studied eight wheelchair-bound patients with RHS (mean age 62.4 years), previously evaluated by computerized tomography scanning, and a control group of normal subjects, matched for age and sex. We assessed routine spirometry, inspiratory and expiratory muscle pressures, breathing pattern and dyspnoea using a modified Borg scale. In six patients, we also measured oesophageal pressure during the maximal sniff manoeuvre and tidal inspiratory swing, and mechanical characteristics of the lung in terms of dynamic elastance during both quiet breathing and a hypercapnic/hyperoxic rebreathing test. During room air breathing, ventilation and tidal volume were similar in patients and controls, while tidal inspiratory swings of oesophageal pressure, an index of inspiratory motor output, were greater in patients ( P =0.005). Patients also exhibited a greater dynamic elastance ( P =0.013). During rebreathing, dynamic elastance remained higher ( P =0.01) and a greater than normal inspiratory motor output was found ( P =0.03). Responses of ventilation and tidal volume to carbon dioxide tension were normal, and in all patients but one a lower Borg score for the unit change in carbon dioxide tension and ventilation was found. In conclusion, a higher than normal inspiratory motor output was unexpectedly associated with a blunted perception of dyspnoea in this subset of RHS patients. This is likely to be due to the modulation of the integration process of respiratory sensation.  相似文献   
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