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41.
Birthweight is an important indicator of child survival. Appropriate and timely care of a newborn specially if he is born with low birthweight is important but this is difficult in developing countries since most of the deliveries are conducted at home where adequate facilities to weigh a new born does not exist. This study was conducted to find out a surrogate which could efficiently be used for detecting low birthweight babies at birth when no weighing machine is around. In this study 41% of the newborn babies were found to weigh less than 2,500 gm at birth. Out of this about 52% were females. The mean chest, thigh and mid-arm circumference at birth for males were 30.89 cm, 15.06 cm and 9.27 cm respectively with standard deviations of 1.83 cm, 1.30 cm and 1.04 cm. Corresponding figures for female babies were 30.69 cm, 15.14 cm and 9.25 cm respectively with standard deviations of 2.08 cm, 1.70 cm and 1.16 cm. Correlation co-efficient between normal birthweight and the chest, thigh and mid-arm circumference were 0.867, 0.845 and 0.842 respectively. A liner regression analysis showed that a chest circumference of 30.14 cm, a thigh circumference of 14.56 cm and a mid-arm circumference of 8.90 cm corresponded well with a birthweight of 2,500 gm. On this basis sensitivity, specificity and predictive values of the chest circumference was better than the other two measurements. However, the mid-arm circumference was observed to be more reliable than the other two measurements for detecting birthweight less than 2,000 gm. A home made measuring tape has been devised on this basis to detect brithweights with cut-off values for 2,500 gm, 2,000 gm to 2,500 gm and 2,000 gm in different shades of colour for illiterate birth attendants.  相似文献   
42.
A case of bilateral vocal cord palsy caused by relapsing polychondritis is presented. The diagnosis was not suspected preoperatively and was made solely on histopathology. A case is made for histological examination of cartilage removed during routine tracheostomy.  相似文献   
43.
1. In the present study we have evaluated whether alpha 2-adrenoceptor binding sites on bovine cerebral cortex membranes labelled by [3H]-clonidine, [3H]-idazoxan and [3H]-RX-821002 can distinguish between known agonists and antagonists. This model has then been used to compare the binding profiles of the putative non-catecholamine, clonidine-displacing substance (CDS), agmatine and crude methanolic extracts of bovine lung and brain. 2. Saturation studies carried out in the presence and absence of noradrenaline, 10 mumol 1(-1), revealed that the maximum number of binding sites on bovine cerebral cortex membranes for [3H]-idazoxan and [3H]-RX-821002 were approximately 60-80% greater than those for [3H]-clonidine (62.6 fmol mg-1 protein). Rauwolscine, the selective alpha 2-adrenoceptor antagonist, was approximately 100 fold more potent against each of the ligands than the selective alpha 1-adrenoceptor diastereoisomer, corynanthine. Also, the pKi value for the selective alpha 1-adrenoceptor prazosin against each ligand was less than 6. 3. Adrenaline, UK-14034, rauwolscine, corynanthine, RX-811059 and prazosin produced concentration-dependent inhibition of binding of all three 3H-ligands. The agonists, adrenaline and UK-14304, were approximately 5 and 10 fold less potent against [3H]-idazoxan and [3H]-RX-821002, respectively, than against [3H]-clonidine. In marked contrast, the antagonists, rauwolscine, corynanthine, RX-811059 and prazosin exhibited a different profile, being approximately 2-3 fold more potent against sites labelled by [3H]-RX-821002 and [3H]-idazoxan compared to sites labelled by [3H]-clonidine.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
44.
An electrochemical quartz crystal microbalance (EQCM) was employed to monitor directly the growth of nickel(II) hexacyanoferrate(III) (NiHCNFe) films on gold substrates during electrodeposition as well as a result of sol-gel aggregation in colloidal nickel ferricyanide solutions used for modification. Frequency changes due to mass changes of the gold/crystal working electrode were correlated with cyclic voltammetric (CV) data. Evidence is also provided for the sorption of counter-cations (Li+, Na+ and K+), and associated water molecules, during redox reactions of the film. There is a strict relationship between the amount of alkali metal ions incorporated into the film during reduction, or excluded from the film during oxidation, and the frequency changes during EQCM measurements. The amount of solvent (H2O) transferred and sorbed in the NiHCNFe film reflects the degree of hydration of the investigated counter-ions. Anions also seem to participate in NiHCNFe electrochemistry, but their role is much less pronounced.  相似文献   
45.
BACKGROUND: Spironolactone is useful in heart failure, but is not given to dialysis patients for fear of hyperkalaemia. This study evaluated the safety of spironolactone administration in haemodialysis patients. METHODS: Fifteen haemodialysis outpatients with mean serum potassium <5.6 mEq/l over the preceding 4 months were treated with spironolactone 25 mg daily for 28 days. Serum potassium was measured before every haemodialysis during the study. Aldosterone and renin were measured at the beginning and end of the study. Patients were monitored for side effects. Data were examined with a paired t-test, with patients serving as their own controls and P < 0.05 considered significant. A sample size of 14 was required to achieve a power of 0.8 and a P = 0.05 to detect a potassium difference of 0.5 +/- 0.6 mEq/l. All patients were analysed as intention-to-treat. RESULTS: The mean potassium level was 4.6 +/- 0.6 mEq/l at baseline and 4.9 +/- 0.9 mEq/l at study completion (P = 0.14). Thirteen patients completed the trial with no potassium levels >6.0 mEq/l. Four patients had potassium levels between 5.5 and 6.0 mEq/l. One patient was withdrawn at day 20 after developing hyperkalaemia (7.6 mEq/l). Another patient was withdrawn at day 25 after missing a dialysis treatment. There were no differences in either baseline or 28 day aldosterone or renin levels (16.8 +/- 28.8 vs 11.7 +/- 6.1 ng/dl and 3.5 +/- 3.9 vs 3.5 +/- 3.5 ng/ml/h, respectively). Infrequent side effects included dry mouth, nosebleed, pruritis, gynecomastia and diarrhoea. No significant leukopenia or anaemia was noted. CONCLUSIONS: Spironolactone may be considered as a treatment option for selected chronic haemodialysis patients with heart disease.  相似文献   
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47.
Between January 1941 and June 1989, 46 children below the age of 18 with an arteriovenous malformation (AVM) were managed. There were 7 patients with AVM diagnosed before the age of 2; 10 patients were diagnosed between the ages of 3 and 10; and 29 patients were diagnosed between 11 and 18. There were equal numbers of male and female patients. Twenty-five of the AVMs were large (>5 cm longest diameter). All 7 AVMs diagnosed before the age of 2 were large. The usual clinical presentation was congestive heart failure, bruit and an enlarging head. Three patients underwent excision with 2 deaths and 1 excellent result. In 11 patients (aged 3–18) with AVM without history of hemorrhage, 3 had excision with 2 excellent and 1 fair result. Four remained stable. Four developed progressive deficits or hemorrhage. In 10 patients (aged 3–18) with AVM and hemorrhage who were treated medically, 7 (70%) had an episode of re-hemorrhage. Three patients had excision of AVM after re-hemorrhage, but before the age of 18 with an excellent result. Eighteen patients (aged 3–18) with AVM and a single episode of hemorrhage underwent excision with 17 excellent or good results and 1 fair result. The overall mortality was 7%. Eighty-five percent of the children with excision of AVM had an excellent or good result. The best treatment for AVM in children is surgical excision.Presented at the XVII Annual Meeting of the International Society for Pediatric Neurosurgery, Bombay 1989  相似文献   
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Prodrugs of -estradiol (1) were prepared with the objective of improving its oral bioavailability. -Estradiol-3-acetylsalicylate (2), -estradiol-3-salicylate (3), and -estradiol-3-anthranilate (4) were synthesized. With these prodrugs the 3-phenolic hydroxy group of estradiol was protected, so that first-pass conjugative metabolism could be reduced. Prodrug hydrolysis rates in dog and human plasma in vitro were determined. Deacetylation of estradiol-3-acetylsalicylate was much more rapid than its hydrolysis to estradiol. In dogs, oral estradiol bioavailability after administration of 2 and 4 was 17-fold and 5-fold higher, respectively, than after oral 1.  相似文献   
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