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101.
This study was carried out to determine the risk of some social and biological maternal factors which may contribute to occurrence of anemia among mothers and preschool children. A community based comparative study was chosen for the conduction of this work. The target population were 400 women in the child bearing period, having at least one preschool child (440). Capillary blood samples were taken by finger prick method and hemoglobin level was estimated by Sahly method. According to the cut off level of hemoglobin, women were classified into anemic and non anemic. In addition to that, 440 preschool children belonging to these women were classified according to the cut off level of their hemoglobin into 165 anemic children and 275 non anemic ones. An interview questionnaire was used to collect the data. Analysis of results showed that age of mother (30 years and above), illiteracy, high parity, history of previous abortion, history of previous perinatal mortality, small inter-birth interval and non use of contraceptives are significant risk factors for mothers. However, mother occupation and state of pregnancy has no role in occurrence of anemia among mothers. In addition to that, high parity, history of previous abortion, history of perinatal mortality, short inter-birth interval, non use of contraceptives and pregnancy are maternal risk factors responsible for anemia among preschool children. While, mother age, education and occupation has no role for occurrence of anemia among preschool children.  相似文献   
102.
103.
Possible effects on the next generation after long-term exposure (subcutaneous administration) of male rats to very high doses of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) were studied. Two dose regimes were applied: TCDD-25 (initial dose: 25 g/kg body wt; maintenance dose: 5 g/kg body wt, once weekly) and TCDD-75 (initial dose: 75 g/kg body wt; maintenance dose: 15 g/kg body wt). Male rats were treated for 10 weeks before mating and then throughout the entire 12 week mating period. They were mated to unexposed virgin females. One group of pregnant females was used for teratological evaluations, and another group was allowed to deliver. No significant differences were observed in the number of implantations or fetuses per litter, and resorption rate, and fetal weight between the controls and TCDD-treated groups. No gross-structural anomalies occurred in any of the fetuses sired by TCDD-treated males. In the TCDD-25 group an increased frequency of two types of variations was observed which also occur in controls: incompletely ossified fingers (TCDD-25=5.1%, controls=2.6%), and incompletely ossified ossa zygomatica (TCDD-25=1.8%, controls=0.5%). In the TCDD-25 group a slight but statistically significant increase was observed in the rate of stillbirths (TCDD-25=1.3%, controls=0.1%), apparently due to an unusually low frequency occurring in the controls (overall historical controls=0.6%). There was no difference in postnatal mortality (TCDD-25=1.3%, controls=1.3%). Taken together, despite the very high doses of TCDD used, the data do not provide evidence for biologically significant paternally-mediated developmental toxicity in the fetuses and newborn.  相似文献   
104.
The effects of a single dose of TCDD on the testis were studied in rats. The animals were treated (subcutaneously) once with TCDD doses of 0, 0.5, 1.0, 3.0, 5.0 g/kg body weight. Doses of 3.0 or 5.0 g TCDD/kg reduced the number of spermatids/testis significantly (60% of the controls). Electron microscopic inspection revealed that both doses led to a dissolution on the germinal epithelium. Altered germ cells at all developmental stages occurred in all testes evaluated. Doses of 0.5 or 1.0 g TCDD/kg did not induce any effects in the testis; therefore, under these experimental conditions of single exposure to rats the dose of 1.0 g TCDD/kg can be considered as NOAEL.  相似文献   
105.
I D Johnston  C Bleasdale  C R Hind    A A Woodcock 《Thorax》1991,46(8):589-591
To determine the accuracy of diagnostic coding of cryptogenic fibrosing alveolitis, the case notes of 166 admissions to four hospitals were reviewed. These consisted of all admissions that had been coded as "idiopathic fibrosing alveolitis" (ICD code 516.3: 97 admissions) or as "postinflammatory pulmonary fibrosis" (ICD code 515.9: 69 admissions). Of 88 available records of admissions coded as idiopathic fibrosing alveolitis, 70 (80%) patients had definite cryptogenic fibrosing alveolitis, and six (7%) possible cryptogenic fibrosing alveolitis according to predetermined conventional clinical criteria. Only seven (8%) admissions were clearly coded wrongly. Sixty four records were available for patients coded as having postinflammatory pulmonary fibrosis; 16 (25%) of these patients had definite cryptogenic fibrosing alveolitis, a further 12 (19%) had possible cryptogenic fibrosing alveolitis or fibrosing alveolitis with a connective tissue disorder, and the remainder had a very wide range of diagnoses. In this study the idiopathic fibrosing alveolitis (ICD 516.3) code was relatively reliable, but a substantial proportion of admissions coded under postinflammatory pulmonary fibrosis (ICD 515.9) also had cryptogenic fibrosing alveolitis and code 515.9 was of little diagnostic value. The data are inadequate for case finding, though in respect of cryptogenic fibrosing alveolitis may be adequate for planning purposes. There continues to be a need for more medical input into the process of diagnostic coding.  相似文献   
106.
From November 1979 through December 1989, 210 distal arteriovenous fistulas were constructed as adjuncts to tibial and peroneal vascular reconstructive procedures in 203 patients threatened with limb loss. Two-year cumulative patency rates were calculated by grouping patients on the basis of changing indications in sequential time periods: group 1 (n = 61): 1979 to 1983, 18%; group 2 (n = 80): 1983 to 1986, 33%; group 3 (n = 69): 1986 to 1989, 44%. Although the therapeutic results observed in these groups are not statistically comparable, they show a perceptible trend. Postoperative arteriography showed that flow is prograde in the distal vessels beyond the distal arteriovenous fistula. Graft surveillance by duplex ultrasonography also confirmed that flow in the distal arteries is prograde and that "steal" does not occur. Peak systolic velocity (174 +/- 38 cm/sec) and mean velocity (92 +/- 23) flow rates are increased in grafts with patent distal arteriovenous fistulas compared to those bypasses with closed distal arteriovenous fistulas (p less than 0.01). There were no differences in the flow measurements for the arteries beyond the distal anastomoses and distal arteriovenous fistulas, confirming the prograde nature of the distal flow. In 22 patients analysis of graft and fistula patency by duplex sonography showed that one fourth of all grafts were patent without fistulas at 1 and 2 years after operation. Alternatively, 68% of patent grafts at 1 year had patent fistulas and 58% had patent fistulas at 2 years. We conclude that the distal arteriovenous fistula will increase graft flow and simultaneously prevent distal arterial overload without causing "steal." This technique should be considered whenever a prosthetic graft is necessary for crural reconstruction and only in selected instances of revascularization with autologous veins.  相似文献   
107.
The initiating and promoting activities of 1,2-dibromoethane in rat liver were investigated using the enzyme-altered foci bioassay. The incidence of -glutamyl-transpeptidase (GGT)-positive foci was used as an early histochemical marker for hepatocarcinogenesis. To determine the initiating activity of 1,2-dibromoethane, the halogenated hydrocarbon was administered orally in corn oil as single or multiple doses (60 or 120 mg/kg) either before or after partial hepatectomy. The animals were then given a promoting regimen of 500 ppm phenobarbital in their drinking water. No increase in the incidence of GGT-positive foci was observed in any of the 1,2-dibromoethane initiation groups. The tumor promoting activity of 1,2-dibromoethane was determined in partially hepatectomized rats which were initiated with N-nitrosodiethylamine (30 mg/kg; po), and one week later were administered 1,2-dibromoethane (10 or 30 mg/kg) orally in corn oil five times weekly for 8 weeks. Control groups receiving sham hepatectomy or no initiator were also treated with the halogenated hydrocarbon five times weekly. Only in those animals which received partial hepatectomy, N-nitrosodiethylamine initiation, and 1,2-dibromoethane was the incidence of GGT-positive foci significantly increased. These results do not support significant initiator activity of 1,2-dibromoethane in rat liver, but do indicate that 1,2-dibromoethane possesses promoter activity which may contribute to its carcinogenic activity.  相似文献   
108.
109.
The large thyroid mass with substernal extension often requires a combination of cervical and thoracic approach for its access and removal. We have developed a technique that uses a cervical incision and combines clear access to the mass with low morbidity. The principle features include complete sternocleidomastoid mobilization, early identification of the neurovascular pedicle through a lateral approach, and finger dissection to deliver the substernal component of the mass. This article also describes the elements of our technique in detail, from preoperative considerations through wound closure and discusses the debate concerning the ideal treatment of these challenging tumors.  相似文献   
110.
BACKGROUND AND PURPOSE: Single agent mitomycin c (MMC) has been shown to improve the outcome of radiotherapy in single institution trials. In order to confirm these findings in a broader worldwide setting, the International Atomic Energy Agency (IAEA) initiated a multicentre trial randomising between radiotherapy alone versus radiotherapy plus MMC. MATERIAL AND METHODS: Patients with advanced head and neck cancer were treated with primary curative radiotherapy (66 Gy in 33 fractions with five fractions per week) +/-a single injection (15 mg/m(2)) of MMC at the end of the first week of radiotherapy. Stratification parameters were tumour localization, T-stage, N-stage, and institution. A total of 558 patients were recruited in the trial from February 1996 to December 1999. Insufficient accrual and reporting led to the exclusion of three centres. The final study population consisted of 478 patients from seven centres. Patients had stage III (n=223) or stage IV (n=255) squamous cell carcinoma of the oral cavity (n=230), oropharynx (n=140), hypopharynx (n=65) or larynx (n=43). Prognostic factors like age, gender, site, size, differentiation and stage were well balanced between the two arms. RESULTS: The haematological side effects of MMC were very modest (<5% grade 3-4) and did not require any specific interventions. Furthermore, MMC did not enhance the incidence or severity of acute and late radiation side effects. Confluent mucositis and dry skin desquamation was common, occurring in 56% and 62% of patients, respectively. The overall 3-year primary locoregional tumour control, disease-specific and overall survival rates were 19, 36 and 30%, respectively. Gender, haemoglobin drop, tumour site, tumour and nodal stage were significant parameters for loco-regional tumour control. There was no significant effect of MMC on locoregional control or survival, except for the 161 N0 patients, where MMC resulted in a better loco-regional control (3-year estimate 16% vs. 29%, P=0.01). CONCLUSIONS: The study did not show any major influence of MMC on loco-regional tumour control, survival or morbidity after primary radiotherapy in stage III-IV head and neck cancer except in N0 patients where loco-regional control was significantly improved.  相似文献   
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