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991.
Irish Journal of Medical Science (1971 -) -  相似文献   
992.
Background We studied the effectiveness of Radiofrequency (RF) modified maze in early and late restoration of sinus rhythm in patients with rheumatic heart disease (RHD). Methods We studied 84 patients with RHD over 23.6±12.5 months after the RF modified maze and another group of 64 patients over six months after valvular surgery alone (the Non-Maze group). Any thromboembolic episodes and NYHA class of the patient were recorded. The short term survivors in sinus rhythm, underwent stress test and echocardiography for atrial transport function at 3–6 months after surgery. Results In the Maze group, sinus rhythm was restored in 60/70 patients (85.71%) immediately and sustained in 55/70 patients (78.57%) over the follow-up as against an immediate conversion rate of 5.3% (5/53 patients, p<0.001) in the Non-maze group. The additional Cardiopulmonary (CP) bypass time (p=0.13) and cross clamp time (p=0.511) needed for maze is not statistically significant. Left atrial (LA) transport function was preserved in 41/51 patients (80.4%) and Right atrial (RA) transport function in 51/51 patients (100%). Stress test showed good chronotropic response in all the 41 patients in whom it was performed. In the Maze group one patient presented with acute valve thrombosis and subsequently, succumbed to it. In the non maze group 3/55 patients (5.66%) were hospitalized for stroke. No patient needed permanent pacemaker nor was sinus node dysfunction seen. The immediate postoperative morbidity and mortality was comparable in the two groups. Conclusions The RF modified maze is safe, effective and brief without any additional risk. It restores sinus rhythm in the majority, however there is an attrition in some.  相似文献   
993.

Background  

Multicentric Castleman's disease (MCD) is a rare disease, but is more frequent in AIDS patients. MCD has only been reported twice before in patients receiving immunosuppressive therapy after renal transplantation, and never in patients receiving immunosuppressive therapy without transplantation. About half of the cases of MCD are human herpesvirus 8 (HHV8) – related, in contrast to Kaposi's sarcoma, a more common complication arising after immunosuppression, where the virus is found in virtually all cases.  相似文献   
994.

Background  

The chemokine stromal derived factor-1 (SDF-1 or CXCL12) and its receptor CXCR4 have been demonstrated to be crucial for the homing of stem cells and prostate cancers to the marrow. While screening prostate cancers for CXCL12-responsive adhesion molecules, we identified CD164 (MGC-24) as a potential regulator of homing. CD164 is known to function as a receptor that regulates stem cell localization to the bone marrow.  相似文献   
995.
The expression of mismatch repair proteins hMSH2 and hMLH1 was investigated in human ovarian cancer cell lines and in biopsies of ovarian carcinomas obtained from 20 patients undergoing surgical operation. By Western blotting analysis hMSH2 protein was detected in all the tumor samples analyzed and in eight out of nine human ovarian cancer cell lines, while hMLH1 was undetectable in four out of 20 ovarian tumors and in five out of nine human ovarian cancer cell lines analyzed. The possible presence of frameshift mutations in the BAX gene, which contains a sequence of eight contiguous guanines in its third exon, was tested in all the samples. All the cell lines presented the normal alleles for the BAX gene while only in one of the tumor samples a heterozygous frameshift mutation was found. The frameshift mutation was associated to a low, almost undetectable, level of BAX protein which was instead present at much higher levels in all the other samples investigated. The results indicate that frameshift mutations in the BAX gene, possibly arising as a consequence of microsatellite instability (detectable in these tumors), is detectable in human ovarian cancer although quantitatively it does not appear to be a major determinant of the low apoptotic response to chemotherapy observed in ovarian cancer cells.   相似文献   
996.
Effects of smoking and aging on oxidative DNA damage of human lymphocytes   总被引:8,自引:5,他引:8  
The effects of H2O2-induced oxidative DNA damage in 80 healthy individuals with relation to age (20-25 and 55-60 years old) and smoking has been investigated with the comet assay technique. Both factors have shown a significant effect upon basal DNA damage with smoking appearing to have the most impact. A differentiation of the four groups response to induced oxidative damage was also observed. A distinctly separate behavior of the younger non-smokers group, when compared with the rest of the categories, was found. This is attributed to the lower degree of initial basal damage that occurs in their lymphocytes.   相似文献   
997.
To study the effects of carotenoids on the initiation of liver carcinogenesis by aflatoxin B1 (AFB1), male weanling rats were fed beta- carotene, beta-apo-8'-carotenal, canthaxanthin, astaxanthin or lycopene (300 mg/kg diet), or an excess of vitamin A (21000 RE/kg diet), or were injected i.p. with 3-methylcholanthrene (3-MC) (6 x 20 mg/kg body wt) before and during i.p. treatment with AFB1 (2 x 1 mg/kg body wt). The rats were later submitted to 2-acetylaminofluorene treatment and partial hepatectomy, and placental glutathione S-transferase-positive liver foci were detected and quantified. The in vivo effects of carotenoids or of 3-MC on AFB1-induced liver DNA damage were evaluated using different endpoints: liver DNA single-strand breaks (SSB) induced by AFB1, and in vivo binding of [3H]AFB1 to liver DNA and plasma albumin. Finally, the modulation of AFB1 metabolism by carotenoids or by 3-MC was investigated in vitro by incubating [14C]AFB1 with liver microsomes from rats that had been fed with carotenoids or treated by 3- MC, and the metabolites formed by HPLC were analyzed. In contrast to lycopene or to an excess of vitamin A, both of which had no effect, beta-carotene, beta-apo-8'carotenal, astaxanthin and canthaxanthin, as well as 3-MC, were very efficient in reducing the number and the size of liver preneoplastic foci. In a similar way as 3-MC, the P4501A- inducer carotenoids, beta-apo-8'-carotenal astaxanthin and canthaxanthin, decreased in vivo AFB1-induced DNA SSB and the binding of AFB1 to liver DNA and plasma albumin, and increased in vitro AFB1 metabolism to aflatoxin M1, a less genotoxic metabolite. It is concluded that these carotenoids exert their protective effect through the deviation of AFB1 metabolism towards detoxication pathways. In contrast, beta-carotene did not protect hepatic DNA from AFB1-induced alterations, and caused only minor changes of AFB1 metabolism: seemingly, its protective effect against the initiation of liver preneoplastic foci by AFB1 is mediated by other mechanisms.   相似文献   
998.
OBJECTIVE: To establish the prevalence and incidence of symptoms and complications in children with neurofibromatosis type 1 (NF1) and to assess possible risk factors for the development of complications. DESIGN: A 10 year prospective multidisciplinary follow up study. PATIENTS: One hundred and fifty children diagnosed with NF1 according to criteria set by the National Institutes of Health. RESULTS: In 62 of 150 children (41.3%) complications were present, including 42 (28.0%) children with one complication, 18 (12.0%) with two complications, and two (1.3%) with three complications (mean (SD) duration of follow up 4.9 (3.8) years). Ninety five of the 150 children presented without complications (follow up, 340.8 person-years). The incidence of complications was 2.4/100 person-years in this group. An association was found between behavioural problems and the presence of complications. CONCLUSION: This is the largest single centre case series of NF1 affected children followed until 18 years of age. Children with NF1, including those initially presenting without complications, should have regular clinical examinations.  相似文献   
999.
Mothers'perceptions of desirable nutritional practices in infant feeding were examined using a questionnaire consisting of open and closed questions. A total of 1004 mother–infant pairs were recruited from a mixture of urban and rural areas in England. The sample represented a cross–section of socioeconomic groups and educational backgrounds. Mothers'attitudes to healthy eating for infants revealed some misconceptions; 83% felt that a high fibre intake was important or very important and 87% that a low fat intake was important or very important, while 20% considered that plenty of calories was not important. Other health guidelines were appropriately applied and most mothers considered a wide variety of foods, plenty to drink and a low sugar and salt intake to be important. These beliefs were representative of the sample population, irrespective of the socioeconomic group, location, age and education of the mother.  相似文献   
1000.
The causes, classification, and prevention of mechanical asphyxial death in children were examined. The Office of Population Censuses and Surveys (OPCS) identified children, under 15 years of age, who had died as a result of choking, suffocation, or strangulation in England and Wales during the years 1990 and 1991. Cases in the International Classification of Diseases (ICD) codes of E911-3, E953, E963, and E983 were selected and case details from HM coroners' records and the death certificates were extracted. The OPCS identified 136 children (99 boys, 37 girls) in the two year period, 65% were under 3 years of age. The children were classified as dying from choking (21 cases), aspirating gastric contents (39 cases), suffocation (29 cases), strangulation (11 cases), and hanging (36 cases). The strangulation cases could be further subdivided into a group of 12 younger children who were suspended from ligatures around the home and a group of 21 boys (8-14 years) who died of self initiated hanging. Overall, 11 children were deliberately killed and 31 children died in beds or cots. Children whose deaths are classified as being due to aspiration of vomit appear to be cases of the sudden infant death syndrome or background medical conditions. This study suggests the need for advice on maintaining a safe sleeping environment. Only one child choked on a toy and European Standards for Toy Safety appear to have been successful. The prevention of hanging in the group of older boys needs further exploration.  相似文献   
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