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31.
The influence of family history of hypertension, myocardial-infarction and/or stroke on the blood pressure levels of 3,194 children in the age group 5-15 years was studied. Compared to children of normotensive parents, subjects coming from families with history of uncomplicated hypertension, complicated hypertension (hypertension plus myocardial infarction or stroke) and myocardial infarction or stroke without history of hypertension tended to have significantly higher levels of both systolic and diastolic pressures (p less than 0.001) in both the sexes in all age groups studied. Further, 15 (4.83%) of the children coming from families with positive history of one of the aforesaid morbid cardiovascular events had persistent hypertension (BP greater than mean +2 SD for age and sex). On the contrary only one (0.03%) of the 2,884 children belonging to normal parents had persistent hypertension. All the 16 children with sustained hypertension had only mild hypertension and were asymptomatic. Ten (62.5%) of them were obese (weight/height2 greater than 2.26). Baseline investigations failed to detect underlying cause to account for raised blood pressures in 9 of the 16 cases that could be investigated. These findings suggest that children of people with hypertension or other morbid cardiovascular events are more likely to have persistently elevated blood pressures than children from families without such a history.  相似文献   
32.
Our experience of single-stage repair of severe hypospadias (penoscrotal, scrotal, and perineal) in 30 children using urinary bladder mucosa for urethroplasty is reported. These children had severe chordee, small prepuce, and often ventral transposition of the penis with bifid scrotum where Devine and Horton, Asopa, or Duckett techniques are not so suitable. The graft uptake was uniformly satisfactory. Ten patients had complications; most of the fistulae healed spontaneously. Surgical intervention was required in 2 cases only: 1 for a fistula and another for a stricture with fistula. Meatal stenosis, seen in 4 cases, led to delayed distal fistulae in 2, which healed spontaneously with meatal dilatation. Regular dilatation of the external meatus is recommended to prevent this problem.  相似文献   
33.
Standardization of allergens are achieved by in vitro and in vivo methods. Some of the allergens from Western countries are standardized using biological potency of the extracts but no attempt has been made till now to standardize any of the pollen extracts from India based on biological units. Therefore, we have attempted to standardize two important pollen allergens Ricinus communis and Holoptelea integrifolia by biological methods. Broadly the methods adopted by Dreborg and Grimmer (1983) was followed. Skin prick tests were carried out with the extracts of R. communis and H. integrifolia on 15 allergic patients in five three fold log dilutions starting with 1:10, in 50% glycerinated buffer. Glycerinated buffer (50%) and histamine dihydrochloride (1 mg/ml) were used as negative and positive controls, respectively. The mean wheal diameter obtained with different concentrations showed a gradual systematic fall with increase in dilution. The mean relative diameter (% of histamine reaction) varied from 124.1 +/- 8.9 to 33.7 +/- 6.1 and 78.9 +/- 5.5 to 21.4 +/- 3.8 with the highest and lowest concentrations of R. communis and H. integrifolia pollen antigens, respectively. The histamine equivalent concentration of antigen 1,000 Biological Units (BU) obtained for crude pollen extracts of R. communis and H. integrifolia was 1:17 and 1:22 respectively.  相似文献   
34.
Frequency of sickle cell in Scheduled Caste and Scheduled Tribe populations was found to be 1.5 and 14.9% respectively, whereas G-6-PD deficiency was 5.9 and 4.2% respectively. Blood group B was dominant in both the communities. A significantly lower frequency of P. falciparum malaria was observed among sicklers.  相似文献   
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Total and subcellular (cytosol and nuclear) concentrations of estrone (E1), estradiol (E2), and androstenedione were determined in non-malignant (n = 61) and malignant (n = 65) human breast tissues obtained from post-menopausal women. The 17 beta-hydroxysteroid dehydrogenase (17 beta-OH-SDH) activity was determined in 800g supernatant fraction. Total estrogens, E1 and E2 levels and 17 beta-OH-SDH activity were significantly (p less than 0.005, 0.0005, 0.001, respectively) higher in malignant than in non-malignant breast tissues. We failed to observe significant changes in subcellular steroid concentrations or enzyme activity associated with patients' obesity or tumor estrogen receptor status. When the steroid levels were analyzed in relation to clinical staging of the disease, nuclear contents of estradiol were significantly higher (p less than 0.005) in Stage-IV patients than in those with less advanced disease (Stages I to III). 17 beta-OH-SDH activity was significantly (p less than 0.001) lower in patients with advanced disease than in those with relatively less advanced (Stages I to III) disease and was positively correlated with tissue concentration of androstenedione. Our present data indicate that differential intracellular metabolism of steroid hormones may have some influence on availability of estradiol at nuclear sites. In postmenopausal women, local interconversion of estrogens may provide sufficient estrogenic stimulus to enhance the growth and progression of breast tumors.  相似文献   
38.
Cumulative exposure to the neurotoxicant acrylamide produces axonal damage in the distal ends of both central (CNS) and peripheral (PNS) nerve fibers and subsequent hind-limb paralysis. The messenger RNA which codes for the PNS myelin glycoprotein P0 (P0-mRNA) was used to monitor this toxic neuropathy in Sprague Dawley rats prior to, concurrent with, and subsequent to, ultrastructurally and immunocytochemically defined nerve damage. Rats were dosed every other day with acrylamide (50 mg/kg, IP) and sampled intermittently throughout a 4 week exposure period. Slot blot and Northern gel analyses of the proximal and distal sciatic nerve were used to determine a quantitated measure of P0-mRNA. Twenty-four hours after the first treatment, in the absence of ultrastructural damage, P0-mRNA increased 55% over control levels in the distal sciatic nerve. After 12 treatments, and concomitant with the appearance of spinal cord and PNS neuropathic damage and hindlimb dysfunction, P0-mRNA decreased 45% below control levels. Levels of P0-mRNA from rats exposed to 12 treatments of acrylamide but allowed to recover for 40 days, returned to 79% of control values to reflect the regeneration and remyelination occurring in the distal sciatic nerve. In spite of these fluctuations in levels of P0-mRNA, immunocytochemical staining of P0 protein in plastic sections of the distal sciatic nerve was present throughout all sample times. These results suggest that changes in neural specific mRNAs are sensitive to neurotoxic damage and can be used to monitor the pathogenesis of nerve degeneration.  相似文献   
39.
In the present study 108 full time workers employed in various sections of a railway workshop and exposed to smoke and irritant fumes, and 45 matched control subjects from local administrative staff were investigated to find prevalence of chronic bronchitis. In all 18 (16.7%) workers and 4 (8.9%) control subjects had clinical evidence of chronic bronchitis. Peak expiratory flow rate less than 300 L/min was observed in 54.6% workers and 2.2% control subjects. A significantly higher prevalence of chronic bronchitis was seen in workers. The advancing age, smoking and duration of exposure had significant influence on prevalence of chronic bronchitis.  相似文献   
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