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91.
92.

Background

Toxocariasis is a common disease around the world. Our objective was to determine Toxocara seroprevalence in humans in the city of Isparta, Southwest Turkey, in respect of some determinants such as age, socio-economic level, residence in city center or rural area etc.

Methods

Five hundred and thirty four individual participants from Isparta center and 85 from Asagi Gokdere village were included in the study. T. cati specific antibodies were analyzed using excretory-secretory (ES)-enzyme-linked immunosorbent assay (ELISA) method.

Results

T. cati antibodies were detected as positive in 73 (13.6%) of 534 samples which were collected from subjects living in the city center and 24 (28.2%) of 85 samples from Asagi Gokdere village. Toxocara seropositivity was detected among 15.6% of whole study group. The seroprevalence of toxocariasis was significantly higher among subjects from village than in subjects from city center (P=0.001). While gender, high school education, source of the water which is used, family income and geophagia/eating nail behaviors were the features which were detected as being associated with toxocariasis seropositivity (odds ratios=0.5; 6.52; 3.61; 0.43; 0.13 respectively), owning dogs or cats and hand washing were detected as being not associated with toxocariasis seropositivity (P>0.05). Furthermore, Toxocara seropositivity was significantly higher among subjects in 0–10 than >40 year-old group (P=0.02).

Conclusion

It can be suggested that untreated lost pet population, environmental contamination, and way of life have influence on the epidemiology of toxocariasis.  相似文献   
93.

Introduction

We evaluated the sub-chronic toxicity of the aqueous herbal extract prepared fromCassytha filiformis and administered daily for 28 days at dose levels (250, 500, and 1000 mg/kg bw) in male wistar albino rats. The LD50 of the aqueous extract was determined.

Methods

The effects on body weights, organ weights, and certain haematological and plasma biochemical parameters were measured as indices of organ toxicity.

Results

The aqueous extract did not affect plasma glutamate oxaloacetate transaminase (GOT) and glutamate pyruvate transaminase (GPT); however, a significant reduction in alkaline phosphatase (ALP) level occurred in all the treated groups. It also did not affect the electrolytes (Na+, Cl? and K+), total and direct bilirubin, creatinine, and glucose level. The aqueous extract elicited hypercholesterolaemic effects, but it did not affect the Hb, WBC, RBC, PVC, platelets, MCH, MCHC, MCV levels and differential counts (lympocytes, neutrophils, monocytes, eosinophils and basophils). It also reduced the body weight gain and absolute weight of the kidneys. The relative weights of the heart and lungs in some animal groups were equally reduced. The acute toxicological evaluation of the plant extract revealed an oral LD50 value greater than 500 mg/kg bw.

Conclusion

This study suggests that aqueous extract ofC. filiformis administered at normal therapeutic doses is not likely to produce severe toxic effects on some organs or haematological and biochemical indices in rats.  相似文献   
94.
The organoselenium compounds benzyl selenocyanate (BSC) and 1,4- phenylenebis(methylene)selenocyanate (p-XSC), as well as sodium selenite, are effective chemopreventive agents for various chemically induced tumors in animal models at both the initiation and postinitiation stages. The mechanisms involved at the postinitiation stage are not clear. Because several lines of evidence indicate that inhibition of excess DNA (cytosine-5)-methyltransferase (Mtase) may be a sufficient factor for the suppression or reversion of carcinogenesis, we examined the effects of sodium selenite, BSC, p-XSC and benzyl thiocyanate (BTC), the sulfur analog of BSC, on Mtase activity in nuclear extracts of human colon carcinomas, and of p-XSC on the Mtase activity of HCT116 human colon carcinoma cells in culture. For this purpose, we developed an improved Mtase assay, in which the incorporation of the methyl-[3H] group from S-adenosyl[methyl- 3H]methionine into deoxycytidine of poly(dI-dC)-poly(dI-dC), is specifically determined by HPLC with radioflow detection after enzymatic hydrolysis, enhancing specificity and reliability. In a variation, using SssI methyltransferase and labeled S- adenosylmethionine, the overall methylation status of DNA in various tissues can also be compared. Selenite, BSC and p-XSC inhibited Mtase extracted from a human colon carcinoma with IC50s of 3.8, 8.1 and 5.2 microM, respectively; BTC had no effect. p-XSC also inhibited the Mtase activity and growth of human colon carcinoma HCT116 cells, with an IC50 of approximately 20 microM. The improved Mtase assay should prove to be a reliable method for screening potential Mtase inhibitors, especially using cells in culture. We suggest that inhibition of Mtase may be a major mechanism of chemoprevention by selenium compounds at the postinitiation stage of carcinogenesis.   相似文献   
95.
血管内皮生长因子(VEGF)和可溶性VEGF受体2(sVEGFR-2)由VEGF通路抑制因子所调控,化疗、VEGFR抑制剂或两者联合治疗是否可引起细胞因子和血管生成因子(CAFs)的改变,而这些改变是否又能预示临床获益?  相似文献   
96.
Factors affecting recurrence in tension-free hernioplasties   总被引:1,自引:1,他引:0  
Summary We investigated the factors affecting recurrence rate in tension-free hernioplasties in the hope of obtaining better results. Tension-free hernioplasty is an easy procedure with very low reported recurrence rates of 0–1.7%. But the causes of failures in open mesh repairs have not been well estabushed. During this prospective study from January 1993 to December 1997 a total of 383 tension free hernioplasties were performed. The influence of some factors including age, sex, type of repaired hernia according to the Nyhus classification, simultaneous bilateral repair, previous hernia operation on the opposite side, chronic constipation, chronic obstructive lung disease, benign prostatic hypertrophy, smoking, previous appendectomy, early postoperative complications and surgical site infection on the recurrence rate were investigated using univariate and multivariate analyses. After a follow-up period of 16 to 62 months (mean 38.2 months) 5 out of 383 repairs failed with a recurrence rate of 1.3%. As a result of logistic regression analysis direct hernia, chronic constipation and surgical site infection were found to be independent risk factors for recurrence. The recurrence rates of tension-free hernioplasties can be reduced by the use of proper surgical techniques, early management of surgical site infection and treatment of chronic constipation.  相似文献   
97.
Although the prevention of unintended adolescent pregnancy is a primary goal of the American Academy of Pediatrics and society, many adolescents continue to become pregnant. Since the last statement on adolescent pregnancy was issued by the Academy in 1989, new observations have been recorded in the literature. The purpose of this new statement is to review current trends and issues on adolescent pregnancy to update practitioners on this topic.  相似文献   
98.
99.
100.
Sparano  JA; Wiernik  PH; Strack  M; Leaf  A; Becker  N; Valentine  ES 《Blood》1993,81(10):2810-2815
Fourteen patients with poor-prognosis intermediate- to high-grade non- Hodgkin's lymphoma (NHL) associated with human immunodeficiency virus (HIV) infection (12 patients) or human T-cell leukemia virus type I (HTLV-I) infection (two patients) received cyclophosphamide 750 mg/m2, doxorubicin 50 mg/m2, and etoposide 240 mg/m2 administered as a continuous intravenous (IV) infusion over 4 days (infusional CDE); treatment was repeated every 28 or more days for up to six cycles. All HIV-positive patients had at least one poor prognostic feature, which included either extranodal disease (10 patients), Karnofsky performance status less than 70% (six patients), a CD4 count less than 100/microL (six patients), or a prior history of acquired immunodeficiency syndrome (AIDS; one patient). Both HTLV-I-positive patients had an elevated serum lactate dehydrogenase (LDH) level, a poor prognostic feature in that setting. Complete response (CR) occurred in 10 patients (71%; 95% confidence interval, 48% to 95%) and partial response (PR) occurred in three patients (21%), yielding an overall objective response rate of approximately 93%. The estimated Kaplan-Meier median survival was 17.4 months; seven of 12 HIV-positive patients are alive and disease-free with a median follow-up of 15 months (range, 7 to 24 months). Hospitalization was required after 19% of treatment cycles due to fever associated with granulocytopenia. Documented or suspected opportunistic infection occurred in five patients (36%), bacteremia occurred in three patients (21%), and candidemia occurred in one patient (7%). There was one treatment-related death attributable to disseminated aspergillosis. This pilot study suggests that infusional CDE may be a highly active regimen capable of producing durable remissions in a high proportion of patients with HIV-related NHL. Further study is required to confirm this observation.  相似文献   
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