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21.
BACKGROUND: Although administration of the sialyl Lewis(x) oligosaccharide may reduce myocardial injury after ischemia-reperfusion, its effect on coronary and cerebral microvascular regulation and its clinical application during cardiac operation have not been examined. METHODS: Pigs were placed on normothermic cardiopulmonary bypass after 30 minutes of left anterior descending coronary artery occlusion. The hearts were then arrested with cold high potassium cardioplegia. After 1 hour the cross-clamp was removed and the pigs were weaned from cardiopulmonary bypass and perfused for an additional 1 hour. CY-1503 (a sodium salt of the sialyl Lewis(x) oligosaccharide, n = 6) was administered before reperfusion. Six other pigs received saline vehicle. Endothelium-dependent relaxation of precontracted coronary and brain arterioles (70 to 180 microm) to adenosine 5'-diphosphate and endothelium-independent relaxation to sodium nitroprusside were studied in vitro with videomicroscopy. Control values were obtained from uninstrumented pigs. Myeloperoxidase activity in the myocardium and brain was measured to quantify neutrophil infiltration. Cardiac function and perfusion were assessed by left ventricular systolic pressure, maximum rate of increase of left ventricular pressure, left anterior descending coronary artery blood flow and percent segmental shortening, and cerebral vascular resistance, internal carotid artery blood flow, and the constitutively expressed and inducible isoform of nitric oxide synthase mRNA were measured. RESULTS: The impaired myocardial contractile function after ischemia and cardioplegia was not improved by administration of CY-1503. The reduced endothelium-dependent relaxation responses of coronary and brain arterioles during ischemia followed by cardioplegia and cardiopulmonary bypass were improved with CY-1503, but the altered pattern of organ perfusion was not improved. Myeloperoxidase activity was increased in the heart after ischemia-cardioplegia and in the brain after cardiopulmonary bypass. CY-1503 reduced myeloperoxidase activity in both the myocardium and in the brain. Expressions of myocardial inducible isoform or constitutively expressed nitric oxide synthase were not altered in the heart. CONCLUSIONS: Although the sialyl Lewis(x) oligosaccharide does reduce neutrophil infiltration and endothelial injury in the coronary and cerebral microcirculation after cardiopulmonary bypass, it does not have significant beneficial acute effects on organ perfusion or function in the myocardium or brain.  相似文献   
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As part of a program to develop site-specific medications for cocaine abuse, a series of 2-(aminomethyl)-3-phenylbicyclo[2.2.2]- and -[2.2.1]alkane derivatives was synthesized and tested for inhibitory potency in [3H]WIN 35,428 binding and [3H]dopamine uptake assays using rat striatal tissue. Selected compounds were tested for their ability to substitute for cocaine in rat drug discrimination tests. Synthesis was accomplished by a series of Diels-Alder reactions, using cis- and trans-cinnamic acid derivatives (nitrile, acid, acid chloride) with cyclohexadiene and cyclopentadiene. Standard manipulations produced the aminomethyl side chain. Many of the compounds bound with high affinity (median IC50 = 223 nM) to the cocaine binding site as marked by [3H]WIN 35,428. Potency in the binding assay was strongly enhanced by chlorine atoms in the 3- and/or 4-position on the aromatic ring and was little affected by corresponding methoxy groups. In the [2.2.2] series there was little difference in potency between cis and trans compounds or between N, N-dimethylamines and primary amines. In the [2.2.1] series the trans exo compounds tended to be least potent against binding, whereas the cis exo compounds were the most potent (4-Cl cis exo: IC50 = 7.7 nM, 27-fold more potent than 4-Cl trans-exo). Although the potencies of the bicyclic derivatives in the binding and uptake assays were highly correlated, some of the compounds were 5-7-fold less potent at inhibiting [3H]dopamine uptake than [3H]WIN 35,428 binding (for comparison, cocaine has a lower discrimination ratio (DR) of 2.5). The DR values were higher for almost all primary amines and for the trans-[2.2.2] series as compared to the cis-[2.2.2]. Most of the compounds had Hill coefficients approaching unity, except for the [2. 2.2] 3,4-dichloro derivatives, which all had nH values of about 2.0. Two of the compounds were shown to fully substitute for cocaine in drug discrimination tests in rats, and one had a very long duration of action.  相似文献   
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One hundred patients undergoing abdominal surgery were included in this prospective study. The role of local application of Betadine, use of synthetic sutures, and use of low pressure subcutaneous suction drainage were evaluated in preventing post-operative wound infection. The infection rate was 15 per cent with Betadine, 15.4 per cent with prolene, 20 per cent with subcutaneous suction drainage and 30.8 per cent in the control group.KEY WORDS: Surgical wound infection, Betadine, Sutures, Infection control  相似文献   
25.
The prevalence of osteopenia in children with inflammatory bowel disease (IBD) is unknown. The effect of nutritional state, disease activity, and steroid therapy on bone mineral content (BMC) of whole body, lumbar spine, and left femoral neck measured by dual energy x ray absorptiometry in 32 children with IBD was assessed by comparison with 58 healthy local school children. Using the control data, a predicted BMC was calculated taking into account bone area, age, height, weight, and pubertal stage. The measured BMC in children with IBD was expressed as a percentage of this predicted value (% BMC). Mean (SD) % BMC was significantly reduced for the whole body and left femoral neck in the children with IBD (97.0 (4.5)% and 93.1 (12.0)% respectively, p < 0.05). Of the children with IBD, 41% had a % BMC less than 1 SD below the mean for the whole body and 47% at the femoral neck. Reduction in % BMC was associated with steroid usage but not with the magnitude of steroid dose, disease activity, or biochemical markers of bone metabolism. In conclusion, osteopenia is relatively common in childhood IBD and may be partly related to the previous use of steroids.  相似文献   
26.
Background Recent epidemiologic data on travelers— diarrhea (TD) are essential for the evaluation of conventional and future prophylactic and therapeutic measures.
Methods To determine the epidemiology, including risk factors, impact and quality-of-life evaluation of TD, a cross-sectional survey was conducted over 12 months at the airports of Mombasa (Kenya), Goa (India), Montego Bay (Jamaica) and Fortaleza (Brazil) by distributing questionnaires to visitors just prior to their flying home. The study period was March 1996 to July 1998.
Results Overall, 73,630 short-term visitors completed a questionnaire. The total diarrhea attack rate varied between a high of 54.6% in Mombasa and a low of 13.6% in Fortaleza, but only between 31.5% and 5.4% of all travelers had classic TD. The 14-day incidence rates varied between 19.5% and 65.7%. Few travelers meticulously avoided potentially dangerous food items, although in India and Kenya most travelers avoided those considered most dangerous. Risk factors were stays exceeding 1 week, age between 15 and 30 years, and residence in the UK. The impact, measured as incapacity or quality-of-life scores, was very considerable.
Conclusions TD continues to affect vacationers and business travelers as frequently as it did some 20 years ago. Compliance with recommendations to reduce exposure to pathogens by avoiding dangerous food items is poor among travelers from all countries. Implementation of food safety education programs may be difficult to achieve.  相似文献   
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Objective  To evaluate serum insulin levels and insulin sensitivity in women with polycystic ovary syndrome (PCOS) in relation to their glycaemic status.
Design  An observational study.
Setting  A tertiary-level reproductive health centre in Sri Lanka.
Sample  Infertile women diagnosed as having PCOS ( n  = 168) on the basis of the Rotterdam criteria were included in the study.
Methods  Glycaemic status and serum insulin values were assessed at fasting and at 2 hours after a 75-g oral glucose load and stratified as diabetes mellitus (DM) (10.12%), impaired glucose tolerance (IGT) (23.21%) and normoglycaemia (66.67%). The normoglycaemic group was restratified as groups A (10.7%), B (79.5%) and C (9.8%) on the basis of serum insulin levels, with group A having the lowest and group C the highest values. The Quantitative Insulin Sensitivity Check Index (QUICKI) scores of women with DM and IGT and those in groups A, B and C in the normoglycaemic category were compared.
Main outcome measures  Insulin sensitivity in these groups of women.
Results  Body mass index (BMI) exceeded 23 kg/m2 in 77.38% of the women. In normoglycaemic women with PCOS, insulin sensitivity was highest in group A. In groups B and C, insulin sensitivities corresponded to those found for women with IGT and DM respectively. This pattern was also reflected in the BMI.
Conclusions  Normoglycaemic women with PCOS are heterogeneous regarding insulin sensitivity. The treatment offered to those with DM and IGT could be extended to subgroups B and C of normoglycaemic subjects. Normoglycaemic women with PCOS with high insulin sensitivity (group A) would not qualify for this treatment.  相似文献   
30.
Cyprinid herpesvirus-3 (CyHV-3) induces the highly contagious koi herpesvirus disease (KHVD) and may result in significant economic losses to the ornamental and food-producing carp industry. Suspicion of KHVD is triggered by clinical signs and confirmed using laboratory techniques. The latter are labour- and time-consuming, require specialised equipment and trained personnel. For rapid, on-site detection of CyHV-3, a lateral flow device (LFD) was developed using two monoclonal antibodies directed towards the viral glycoprotein ORF65. The LFD was highly specific with analytical and diagnostic specificities of 100%. Analytical sensitivity ranged between 1.25 × 102 and 2.40 × 104 plaque forming units per ml for isolates originating from geographically distinct regions. In experimentally infected carp, CyHV-3 was detected as early as 4–5 days post infection. Diagnostic sensitivities of 52.6% and 72.2% relative to PCR were recorded, depending on the viral isolate used. When onset of mortality was taken as reference, diagnostic sensitivities increased to 67.0% and 93.3%. The diagnostic sensitivity for freshly found-dead animals was 100%, irrespective of the virus isolate used. Given the high specificity and ease-of-use for on-site detection of CyHV-3, the LFD was regarded fit for purpose as a first-line diagnostic tool for the identification of acute CyHV-3 infections in KHVD affected (koi) carp.  相似文献   
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