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Clostridium sordellii was isolated from 37 sheep, in 29 flocks, which died suddenly between 1993 and 1995. The sheep were of all ages, but the most severe gross lesions affected lambs four to 10 weeks of age. In older weaned lambs and ewes the gross changes were less marked and more variable. Thirty sheep suffering from a variety of other conditions were examined and C sordellii was not isolated. The isolation of C sordellii has been reported only twice before from sheep in Britain, and on both occasions no detailed investigations were described. The evidence from this study indicates that C sordellii should be considered when investigating the cause of sudden death in sheep of all ages in Britain.  相似文献   
44.
A foal with retained cartilage in the distal metaphysis of the right and left radii and third metacarpal bones had abnormal physeal vasculature. In areas where cartilage was retained, vessels crossed the physis, and branched at the physeal-metaphyseal junction or at the site of retained cartilage. Vessels appeared to be involved in re-initiation of endochondral ossification and in the repair reponse to the presence of retained cartilage. In areas where the physis was radiographically and histologically normal, no vessels crossed the physis. A function of transphyseal vessels may be as a reserve blood supply in areas of metaphyseal abnormality, at a stage of maturity when metaphyseal vessels are not well developed.  相似文献   
45.
A framework for analysis of data quality research   总被引:14,自引:0,他引:14  
Organizational databases are pervaded with data of poor quality. However, there has not been an analysis of the data quality literature that provides an overall understanding of the state-of-art research in this area. Using an analogy between product manufacturing and data manufacturing, this paper develops a framework for analyzing data quality research, and uses it as the basis for organizing the data quality literature. This framework consists of seven elements: management responsibilities, operation and assurance costs, research and development, production, distribution, personnel management, and legal function. The analysis reveals that most research efforts focus on operation and assurance costs, research and development, and production of data products. Unexplored research topics and unresolved issues are identified and directions for future research provided  相似文献   
46.
Eighty-five consecutive patients were randomized to undergo mass closure of the abdomen with no. 1 polydioxanone mounted on either a blunt-tipped (n = 46) or cutting (n = 39) needle. Gloves were changed before closure and tested for perforation afterwards using standard air or water techniques. Fourteen pairs of gloves were punctured when using a cutting needle, and three pairs when a blunt-tipped needle was used. The majority of punctures were to the non-dominant glove. The surgeon was aware of the puncture in eight of the 14 instances involving a sharp needle and in one of the three involving a blunt-tipped needle. Blunt-tipped needles, while not eliminating the risk, significantly reduced the incidence of surgical glove puncture (P < 0.001, Fisher's exact test). The use of cutting needles for abdominal closure should be abandoned.  相似文献   
47.
The role of the sensitivity of bone marrow cells to, and the pharmacokinetics of granulocyte colony-stimulating factor (G-CSF) on the rhythm of leukocyte-increasing effect was investigated in ICR male mice housed under a standardized light-dark cycle (lights on at 0700, off at 1900). A significant circadian rhythm was demonstrated for leukocyte counts at 24 hr after G-CSF (250 microg/kg, s.c.) injection at six different circadian times (P < .01). The leukocyte counts of mice given G-CSF at 0500, 0900, 1300 or 1700 were significantly higher than those of mice given G-CSF at 2100 (P < .01, respectively). The rhythmic pattern resembled overall the rhythm occurring after saline injection. In the comparison between leukocyte counts after G-CSF injection at 0700 and 1900, the time when leukocyte counts are equal in nondrugged state, the leukocyte counts at 24 hr after G-CSF (250 microg/kg, i.v.) injection were approximately 50% higher in mice injected with the drug at 0700 than at 1900 (P < .01). Bone marrow cultures obtained at two times of day resulted in different numbers of myeloid colonies even when treated with the same concentrations of G-CSF in vitro. The colony-forming activity of G-CSF was significantly more potent at 0700 than at 1900 (P < .01). The plasma G-CSF concentrations after G-CSF (250 or 5 microg/kg, i.v.) injection were significantly higher in mice receiving injections with the drug at 0700 than at 1900 (P < .05, respectively). The area under the curve and mean residence time were significantly larger in mice injected with the drug at 0700 than at 1900 (P < .01, P < .05, respectively). Our suggests that the rhythm of G-CSF activity is caused by that of the sensitivity of bone marrow cells to, and the pharmacokinetics of the drug.  相似文献   
48.
The anxiolytic potential of the selective sigma2 ligand 1-[4-[1-(4-Fluorophenyl)-1H-indol-3-yl]-1-butyl]spiro[isobenzofuran-1(3H),4-piperidine] [corrected] (Lu 28-179) was assessed in various animal models of anxiety in rodents. Lu 28-179 facilitated the exploratory behavior of mice and rats in the black and white two-compartment box over a large dose range. In the rat, the minimal effective dose (MED) was 0.18 nmol/kg (0.1 microg/kg), and in the mouse, the MED was 0.00018 nmol/kg (0.1 ng/kg). The anxiolytic-like effect was maintained after treatment with 1 microg/kg/day for up to 14 days, and no anxiogenic-like effects were seen upon withdrawal from repeated treatment. Lu 28-179 increased the time that pairs of rats spent in active social interaction (unfamiliar high-light conditions), MED = 0.1 ng/kg. Daily treatment with Lu 28-179 (1.8 nmol/kg = 1 microg/kg/day) for up to 4 weeks increased the social interaction time significantly compared with controls, and no anxiogenic-like effects were seen upon withdrawal. Furthermore, Lu 28-179 reversed shock-induced suppression of drinking in the rat (MED = 18,000 nmol/kg = 10 mg/kg). Lu 28-179 did not inhibit footshock-induced ultrasonic vocalization in the rat or isolation-induced aggressive behavior in the mouse. Lu 28-179 was over 100 times more potent than diazepam in the rat and mouse black and white test box and the rat social interaction test, whereas the potency of Lu 28-179 was comparable to that of lorazepam in reversal of shock-induced suppression of drinking. Lu 28-179 neither induced sedation nor impaired motor coordination, even at high doses (70,000 nmol/kg = 40 mg/kg). In conclusion, Lu 28-179 exerts potent and long-lasting anxiolytic-like effects in rodents without inducing sedation and withdrawal anxiogenesis.  相似文献   
49.
OBJECTIVES: We sought to determine whether more comprehensive risk-adjustment models have a significant impact on hospital risk-adjusted mortality rates after coronary artery bypass graft surgery (CABG) in Ontario, Canada. BACKGROUND: The Working Group Panel on the Collaborative CABG Database Project has categorized 44 clinical variables into 7 core, 13 level 1 and 24 level 2 variables, to reflect their relative importance in determining short-term mortality after CABG. METHODS: Using clinical data for all 5,517 patients undergoing isolated CABG in Ontario in 1993, we developed 12 increasingly comprehensive risk-adjustment models using logistic regression analysis of 6 of the Panel's core variables and 6 of the Panel's level 1 variables. We studied how the risk-adjusted mortality rates of the nine cardiac surgery hospitals in Ontario changed as more variables were included in these models. RESULTS: Incorporating six of the core variables in a risk-adjustment model led to a model with an area under the receiver operating characteristic (ROC) curve of 0.77. The ROC curve area slightly improved to 0.79 with the inclusion of six additional level 1 variables (p = 0.063). Hospital risk-adjusted mortality rates and relative rankings stabilized after adjusting for six core variables. Adding an additional six level 1 variables to a risk-adjustment model had minimal impact on overall results. CONCLUSIONS: A small number of core variables appear to be sufficient for fairly comparing risk-adjusted mortality rates after CABG across hospitals in Ontario. For efficient interprovider comparisons, risk-adjustment models for CABG could be simplified so that only essential variables are included in these models.  相似文献   
50.
Reports of oral lesions associated with cytomegalovirus (CMV) infection in human immunodeficiency virus (HIV) infected patients are uncommon. In this article a case of CMV infection associated with oral mucosal ulceration and a brief review of the subject is presented. Establishing the cause of ulceration is important in determining a definitive diagnosis and prescribing appropriate therapy. It is important to recognize that CMV associated oral mucosal ulceration may be the initial manifestation of human immunodeficiency virus (HIV) infection.  相似文献   
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