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31.
32.
The derivatization of 5-fluorouracil with 4-bromomethyl-7-methoxycoumarin has been reported previously; however, the structure of the derivative was not confirmed. The synthesis and purification of the 5-FU derivative is described along with the spectroscopic (MS and NMR) determination that it is labelled at both heterocyclic nitrogens as expected. A column switching HPLC system is also presented which consists of primary separation on a cyanopropyl column followed by a final separation on an ODS column with fluorescence detection. This system removes all interferences from the derivatization system and has a limit of detection for the pure derivative of less than 50 fmol (injection volume = 100 microliters).  相似文献   
33.
Operative treatment of infective endocarditis in children   总被引:2,自引:0,他引:2  
A retrospective review of 11 children, aged 2 months to 15 years, demonstrates the feasibility of surgical treatment for infective endocarditis in childhood. Except for one case of perinatal infection, in all instances the infective endocarditis was a complication of a congenital heart defect. As medical treatment was not successful, surgery was indicated. Debridement of infected tissue and repair of the congenital heart defect was performed. There were no septic complications postoperatively although 8 patients were operated upon during the active stage of infection. One 2-month-old child did not survive excision of an infected tricuspid valve. The follow-up period of 8 years to 5 months (median 39 months) showed a good haemodynamic result (NYHA class I) in the remaining 10 patients. This included 4 patients with prosthetic valves.  相似文献   
34.
Female blood donors with low hematocrit levels detected by copper sulfate screening were selected randomly to receive either 75 mg of iron per day, as ferrous gluconate, or a calcium phosphate placebo. Their ferritin, serum iron, total iron-binding capacity, zinc protoporphyrin, and hemoglobin values, as well as their suitability to donate blood, were determined initially (Visit 1) and at four follow-up visits (Visits 2-5). By the second visit, the serum ferritin and iron values of donors receiving iron supplementation differed significantly from those of donors receiving placebo. By the fifth visit, a less marked but significant increase in hemoglobin had occurred in the iron group, but not in the placebo group. At no time was there a significant difference between the groups' suitability to donate blood, with each group donating at almost half of their visits. The authors conclude that iron supplementation at this dose level in deferred female blood donors improves their iron status and hemoglobin levels, but does not significantly increase their suitability to donate blood as compared with the suitability of placebo-treated donors.  相似文献   
35.
Total radical trapping antioxidant potential (TRAP) and exercise   总被引:1,自引:0,他引:1  
The relationship between physical activity, physical fitness and total radical trapping antioxidant potential (TRAP) was examined in the Northern Ireland Health and Activity Survey. This was a cross-sectional population study (n = 1600) using a two-stage probability sample of the population. TRAP was calculated using the sum of the individual serum antioxidant concentrations (urate, protein thiols, ascorbate, alpha tocopherol and bilirubin) multiplied by their respective stoichiometric values. Physical fitness was determined by estimation of VO2max by extrapolation from submaximal oxygen uptake, and physical activity was recorded by computer-assisted interview. Mean serum TRAP concentrations were significantly higher in males (653 +/- 8.2 mumol/l, mean +/- SEM) compared to females (564 +/- 8.0 mumol/l) (p < 0.0001). Both male and female smokers had significantly lower TRAP values than non-smokers (males p < 0.0001, females p = 0.02). In females, there was a positive relationship of TRAP with age (p < 0.001) and body mass index (p < 0.001) but a negative relationship with physical fitness (p < 0.05). The known beneficial effects of exercise and activity do not appear to be directly mediated through increased antioxidant status.   相似文献   
36.
37.
Several small case-control studies have investigated whether factor V Leiden (FVL) is a risk factor for retinal vein occlusion (RVO) and generated conflicting data. To clarify this question we performed a large two-centre case-control study and a meta-analysis of published studies. Two hundred seven consecutive patients with RVO and a control group of 150 subjects were screened between 1996 and 2006. A systematic meta-analysis was done combining our study with further 17 published European case-control studies. APC resistance was detected in 16 out of 207 (7.7%) patients and eight out of 150 (5.3%) controls. The odds ratio (OR) estimated was 1.49 with a (non-significant) 95% confidence interval (CI) of 0.62-3.57. The meta-analysis including 18 studies with a total of 1,748 patients and 2,716 controls showed a significantly higher prevalence of FVL in patients with RVO compared to healthy controls (combined OR 1.66; 95% CI 1.19-2.32). All single studies combined in the meta-analysis were too small to reliably detect the effect individually. This explains the seemingly contradictory data in the literature. In conclusion, the prevalence of APC resistance (and FVL) is increased in patients with RVO compared to controls, but the effect is only moderate. Therefore, there is no indication for general screening of factor V mutation in all patients with RVO. We recommend this test to be performed in patients older than 50 years with an additional history of thromboembolic event and in younger patients without general risk factors like hypertension.  相似文献   
38.
Spontaneus intracerebral haemorrhage is a common cause of stroke especially in the young. The term "spontaneuos intracerebral haemorrhage" refers to bleeding without coincident trauma. About 80% of this haemorrhage occur supratentorial in the basal nuclei and they are associated with hypertension. Etiological factors range from congenital vascular malformations (aneurysmas, AVM, cavernomas) to acquired and degenerative vascular and brain conditions. In primary intracerebral hemorrhage arterial hypertension and consequent vascular changes are the major etiological factors. In secondary- nonhypertensive hemorrhage cause may be associated with aneurysms, AVM, tumors, coagulation disorders. Contemporary diagnosis imaging (CT, MRI) and neurological evaluation, allow early diagnosis and effective medical and/or surgical therapy in a majority patients. Without treatment, the risk of mortality and morbidity is high. Medical management involves normalization of blood pressure, reduction of intracranial pressure, control of brain edema and prevention of seizures. In design for operative treatment must be include age of the patient, hematoma size and location, clinical condition, the level of consciousness and patient outcome. The role of surgery remains contraversial.  相似文献   
39.
Anatomical localisation of skull base meningioma link, their growth and relations with neurovascular structures reduce possibility for radical operation, and offten request additional preoperative or postoperative radiotherapy. We compared personal results of extent surgical resection and skull base meningioma treating outcome with predispose factors scale for surgical radicality and postoperative outcome. We present 42 patients, who were operated in Institute of neurosurgery CCS during the period from 2004 to 2006. RESULTS: Radical resection was possible in 29 cases, and in 13 cases reduction of tumor mass has been performed. Statistical significant predispose factor for radical resection were: absance of preoperative radiotherapy, intact functions of n.III, n.VI, tumor borders inside one skull base fossa and outside of magistral blood vessels. Karnofsky index at the end of following period statistical significant higher in patients with radical resection of skull base meningeioma. Preoperative radiological finding is singificant guide in planning of therapeutic protocol for skull base meningioma. Growth of tumor and relation with neurovascular structures restrict extent of resection and often request additional postoperative radiotherapy or reoperation.  相似文献   
40.
OBJECTIVE: To determine nosocomial transmission of respiratory syncytial virus (RSV) in Canadian pediatric hospitals, outcomes associated with nosocomial disease, and infection control practices. DESIGN: A prospective cohort study in the 1992 to 1994 winter respiratory seasons. SETTING: Nine Canadian pediatric university-affiliated hospitals. PARTICIPANTS: Hospitalized children with symptoms of lower respiratory tract infection (at least one of cough, wheezing, dyspnea, tachypnea, and apnea) and RSV antigen identified in a nasopharyngeal aspirate. RESULTS: Of 1516 children, 91 (6%) had nosocomial RSV (NRSV), defined as symptoms of lower respiratory tract infection and RSV antigen beginning >72 hours after admission. The nosocomial ratio (NRSV/[com-munity-acquired RSV {CARSV})] + NRSV) varied by site from 2.8% to 13%. The median length of stay attributable to RSV for community-acquired illness was 5 days, but 10 days for nosocomial illness. Four children with NRSV (4. 4%) died within 2 weeks of infection, compared with 6 (0.42%) with CARSV (relative risk = 10.4, 95% confidence interval: 3.0, 36.4). All sites isolated RSV-positive patients in single rooms or cohorted them. In a multivariate model, no particular isolation policy was associated with decreased nosocomial ratio, but gowning to enter the room was associated with increased risk of RSV transmission (incidence rate ratio 2.81; confidence interval: 1.65, 4.77). CONCLUSIONS: RSV transmission risk in Canadian pediatric hospitals is generally low. Although use of barrier methods varies, all sites cohort or isolate RSV-positive patients in single rooms. Children with risk factors for severe disease who acquire infection nosocomially have prolonged stays and excess mortality.  相似文献   
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