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Pre-clerking of all patients undergoing elective general surgical operations was introduced at our hospital in an attempt to reduce an unacceptably high operation cancellation rate. A prospective audit has been performed on the effect of this policy on the cancellation rate. Before the introduction of pre-clerking there was a marked seasonal variation in the number of patients who failed to attend for surgery, which could be explained by absence on holiday. This seasonal variation disappeared after the start of pre-clerking clinics, but there has been no reduction in the number of cancellations for medical reasons.  相似文献   
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Impact of clinical history on fracture detection with radiography   总被引:3,自引:0,他引:3  
The effect of knowledge of localizing symptoms and signs in the detection of fractures was studied. Forty radiographs of the extremities were examined twice by seven radiologists; the sessions were separated by 4 months. In 26 cases, a subtle fracture was present; 14 cases were normal. In half of the cases at each session, the precise location of pain, tenderness, or swelling was provided. The observer was asked to determine if the case was normal or abnormal (provide the exact location of the fracture) and to indicate the degree of confidence in the diagnosis. Responses were converted to a numeric scale for analysis. Analysis of receiver operator characteristic parameters indicates that clues regarding location of trauma facilitate detection of fractures. The improvement is based largely on an increased true-positive rate without an increased false-positive rate, regardless of the decision criteria of the radiologist (overall willingness to "overread" or "underread"). This has direct clinical applicability and reinforces the plea of radiologists for precise clinical information.  相似文献   
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王文杰  朱秀媛 《药学学报》1989,24(2):151-154
Lei Wan, Poliporus mylittae Cook et Mass(Omphalia lapidescena Scbraet) is a kind of fungus used in traditional Chinese medicine, as an antheiminthie From Lei Wan, an "active component designated as. S-4001 had been isolated.Preliminary results indicate that S-4001 belongs to D, β, 1-3 glucan with some 1-6 linkages.After administration of S-4001, significant antiinflammatory activity was found in various experimental animal models, including croton oil induced ear edema in mice and agar or yeast induced ankle swelling in rats. An inhibitory action on leucocyte migration inducced by intraperitoneal injection of CMC in rats was also observed. The plasma content of corticosterone was significantly increased, but the content of ascorbic acid in the adrenals did not change in rats given S-4001. Apart from these actions, S-4001 showed a number of immunostimulating actions such as increasing the clearance of Congo red from mice blood and potentiating the immunohemolysis reaction in 615 mice.  相似文献   
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Background  

There is currently an unprecedented expressed need and demand for estimates of maternal mortality in developing countries. This has been stimulated in part by the creation of a Millennium Development Goal that will be judged partly on the basis of reductions in maternal mortality by 2015.  相似文献   
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Lactate production in isolated perfused rat lung   总被引:1,自引:0,他引:1  
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An infant girl with elevated blood lactate, pyruvate, and plasma branched-chain amino acids was diagnosed with dihydrolipoamide dehydrogenase (E3; dihydrolipoamide: NAD+ oxidoreductase, EC 1.8.1.4) deficiency. Activities of the pyruvate dehydrogenase complex and E3 from patient were 26 and 2% of controls in blood lymphocytes, and 11 and 14% in cultured skin fibroblasts, respectively. Western blot analysis demonstrated that the amount of E3 protein in fibroblasts from the patient and her father was about half of controls, while Northern blot analysis showed normal amounts of E3 RNA. DNA sequencing of cloned full-length E3 cDNAs from the patient revealed two mutations in separate alleles. One is a single base insertion of an extra adenine in the last codon of the leader peptide sequence (TAC-->TAAC) leading to a nonsense mutation which results in the premature termination of the precursor E3 polypeptide (Y35X). The other is a missense mutation due to substitution of guanine for adenine, causing an Arg-->Gly substitution at amino acid 460 of the mature protein (R460G) which triggers the loss of E3 activity probably by structural change in the E3 dimer. DNA sequencing of E3 cDNAs from the parents demonstrated that the nonsense mutation was inherited from the father and the missense mutation was inherited from the mother.   相似文献   
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In order to investigate the influence of sutures on intestinal anastomotic healing, 48 rats underwent both ileal and colonic resection. In 24 rats all intestinal sutures were removed 30 min after anastomotic construction (group 1), while in the remaining animals (group 2) the sutures were left in place. Bursting pressures and collagen (hydroxyproline) levels in anastomotic segments were measured 1, 3, and 7 days after operation. Two lethal ileal dehiscences and 9 anastomotic abscesses (5 ileal and 4 colonic) occurred in group 1, while in group 2 there were 3 ileal anastomotic abscesses. On the first day after operation, bursting pressures were significantly lower in sutureless ileal and colonic than in sutured anastomoses. During the post-operative course, changes in collagen concentrations in ileal and colonic segments did not differ between the groups. Thus, sutures are only essential in providing anastomotic strength during the immediate post-operative period, but do not seem to affect post-operative collagen metabolism.
Résumé Dans le but d'étudier l'influence des sutures sur la cicatrisation des anastomoses intestinales, 48 rats ont subi une résection à la fois iléale et colique. 24 rats ont eu une résection de leur suture intestinale 30 minutes après la réalisation de l'anastomose, tandis que chez les animaux restants les sutures étaient laissé en place. 3 à 7 jours après l'opération la pression de rupture et les taux de collagène dans les segments anastomotiques ont été mesurés. Des fistules iléales mortelles et 9 abcés anastomotiques (5 iléaux et 4 coliques) sont survenus dans le groupe expimental contre trois abcés anastomotiques dans le groupe de contrôle. La pression de rupture était significativement plus basse au niveau des anastomoses à la fois iléales et coliques sans suture mais seulement le premier jour après l'opération. Les modifications postopératoires des concentrations de collagène dans les segments iléaux ou coliques ne différaient pas entre les deux groupes. Ainsi les sutures ont seulement un rôle essentiel en renforçant l'anastomose durant la période post-opératoire tout à fait initiale mais ne semblent pas affecter le métabolisme post-opératoire du collagène.
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