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1.
M J Hershman R I Swift D T Reilly W A Logan J M Sackier H Gompertz J Horner N W Baker C B Wood 《Journal of the Royal College of Surgeons of Edinburgh》1990,35(1):29-32
This study compared one dose of cefotetan with three doses of piperacillin as prophylaxis against wound infection in 153 patients undergoing elective colorectal surgery. The patients were randomized into two groups: the first received 2 g cefotetan intravenously with induction of anaesthesia (n = 75), and the second received three doses of 2 g piperacillin (n = 78). Wound infection was defined as the presence of an abscess or discharging pus from the wound. In the cefotetan group there were 14 (19%) wound infections and 13 (17%) in the piperacillin group. There were three septic deaths, one in the cefotetan group and two in the piperacillin group. Both groups were comparable with regard to age, sex, nature of pathology and pre- and perioperative risk factors. No significant haematological or biochemical abnormalities were detected. The only adverse reaction was one patient who had an allergic reaction (rash) to piperacillin. These data suggest that single-dose cefotetan is as effective as triple-dose piperacillin in prophylaxis against infection in elective colorectal surgery. 相似文献
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A polyclonal antiserum which recognizes surface epitopes on IL1-activated pig chondrocytes has been used to immunolocalize chondrocytes responding to IL1 produced during co-culture of pig synovium and articular cartilage. Activation of the chondrocytes by the cytokine was restricted to the articular and subarticular region of the cartilage adjacent to the synovium. Chondrocyte activation was also seen when human rheumatoid synovium was co-cultured with the cartilage. The presence of IL1 in some synovial cells was confirmed by immunolocalization using antisera specific for IL1 alpha and IL1 beta. 相似文献
3.
T J Molloy Y Wang A Horner T M Skerry G A C Murrell 《Journal of orthopaedic research》2006,24(4):842-855
Tendon healing is a complex process consisting of a large number of intricate pathways roughly divided into the phases of inflammation, proliferation, and remodeling. Although these processes have been extensively studied at a variety of levels in recent years, there is still much that remains unknown. This study used microarray analyses to investigate the process at a genetic level in healing rat Achilles tendon at 1, 7, and 21 days postinjury, roughly representing the inflammation, proliferation, and remodeling phases. An interesting temporal expression profile was demonstrated, identifying both known and novel genes and pathways involved in the progression of tendon healing. Both inflammatory response and pro-proliferative genes were shown to be significantly upregulated from 24 h postinjury through to 21 days. Day 7 showed the largest increase in genetic activity, particularly with the expression of collagens and other extracellular matrix genes. Interestingly, there was also evidence of central nervous system-like glutamate-based signaling machinery present in tendon cells, as has recently been shown in bone. This type of signaling mechanism has not previously been shown to exist in tendon. Another novel finding from these analyses is that there appears to be several genes upregulated during healing which have exclusively or primarily been characterized as key modulators of proliferation and patterning during embryonic development. This may suggest that similar pathways are employed in wound healing as in the tightly regulated progression of growth and development in the embryo. These results could be of use in designing novel gene-based therapies to increase the efficacy and efficiency of tendon healing. 相似文献
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The detection of cytotoxicity produced by short-lived reactive intermediates: a study with bromobenzene 总被引:1,自引:0,他引:1
S A Horner J R Fry R H Clothier M Balls 《Xenobiotica; the fate of foreign compounds in biological systems》1987,17(6):777-782
1. A V79 cell incubation incorporating rat liver 9000 g supernatant (S9) fractions, used previously to detect the toxicity due to long-lived, stable metabolites of cyclophosphamide, has been used to study the toxicity of short-lived, reactive metabolites generated from bromobenzene. 2. Cytotoxicity was observed in the presence of S9 fractions from rats treated with phenobarbitone but not in the presence of S9 fractions from untreated or beta-naphthoflavone-treated animals. This toxicity was enhanced by depletion of the glutathione in the S9 fraction by prior treatment of the animals with diethyl maleate and was reduced by SKF 525 A, in agreement with results in vivo on the mechanism of bromobenzene-induced hepatotoxicity. 3. This study demonstrates that cytotoxicity due to the generation of short-lived, reactive metabolites can be detected in this system in vitro provided that procedures are used to modify the activating and detoxifying enzyme systems within the S9 fraction. 相似文献
6.
Hugh Devlin Kety Karayianni Anastasia Mitsea Reinhilde Jacobs Christina Lindh Paul van der Stelt Elizabeth Marjanovic Judith Adams Susan Pavitt Keith Horner 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2007,104(6):821-828
OBJECTIVES: Measurement of cortical thickness and subjective assessment of cortical porosity on panoramic radiographs are methods previously reported for diagnosing osteoporosis. The aims of this study were to determine the relative efficacy of the mandibular cortical index and cortical width in detecting osteoporosis, both alone and in combination, and to determine the optimal cortical width threshold for referral for additional osteoporosis investigation. STUDY DESIGN: Six hundred seventy-one postmenopausal women 45 to 70 years of age were recruited for this study. They received dual energy x-ray absorptiometry (DXA) scans of the left hip and lumbar spine (L1 to L4), and dental panoramic radiographic examinations of the teeth and jaws. Three observers separately assessed the mandibular cortical width and porosity in the mental foramen region of the mandible. Cortical width was corrected for magnification errors. Chi-squared automatic interaction detection analysis (CHAID) software was used (SPSS AnswerTree, version 3.1, SPSS Inc., Chicago, IL). RESULTS: Chi-squared automatic interaction detection analysis showed that the cortical porosity was a poorer predictor of osteoporosis than mandibular cortical width. For the 3 observers, a mandibular cortical width of <3 mm provided diagnostic odds ratios of 6.51, 6.09, and 8.04. The test is therefore only recommended in triage screening of individuals by using radiographs made for purposes other than osteoporosis. CONCLUSION: When evaluating panoramic radiographs, only those patients with the thinnest mandibular cortices (i.e., <3 mm) should be referred for further osteoporosis investigation. 相似文献
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Ascorbic acid added to the basal medium increased the growth response of Lactobacillus casei in folic acid standards. The effect in the serum extracts was not marked, resulting in lowered serum folic acid estimations. However, results obtained on prolonged incubation were similar whether ascorbic acid was added or not. The presence or absence of ascorbic acid and variation of the incubation period may account for differences in reported normal ranges of serum folic acid levels. 相似文献