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991.
PEFR is a simple and reliable way of following patients with bronchial asthma and other obstructive airway diseases. Normal data is available for Caucasian and North Indian children but not for ethnic South Indian children. We, therefore, measured Peak Expiratory Flow Rate (PEFR) in 345 healthy South Indian children aged 4-15 years, using the Wright mini peak flow meter. A nomogram was constructed relating PEFR to height. Prediction equations for PEFR using height alone or height, age and weight were determined for both sexes. The prediction equation for boys based on height alone was PEFR = 4.08 height (cm)--284.55 and for girls was PEFR = 3.92 height (cm)--277.01. 相似文献
992.
993.
994.
MJ Cohn K Patel R Krumlauf DG Wilkinson JD Clarke C Tickle 《Canadian Metallurgical Quarterly》1997,387(6628):97-101
Development of paired appendages at appropriate levels along the primary body axis is a hallmark of the body plan of jawed vertebrates. Hox genes are good candidates for encoding position in lateral plate mesoderm along the body axis and thus for determining where limbs are formed. Local application of fibroblast growth factors (FGFs) to the anterior prospective flank of a chick embryo induces development of an ectopic wing, and FGF applied to posterior flank induces an ectopic leg. If particular combinations of Hox gene expression determine where wings and legs develop, then formation of additional limbs from flank should involve changes in Hox gene expression that reflect the type of limb induced. Here we show that the same population of flank cells can be induced to form either a wing or a leg, and that induction of these ectopic limbs is accompanied by specific changes in expression of three Hox genes in lateral plate mesoderm. This then reproduces, in the flank, expression patterns found at normal limb levels. Hox gene expression is reprogrammed in lateral plate mesoderm, but is unaffected in paraxial mesoderm. Independent regulation of Hox gene expression in lateral plate mesoderm may have been a key step in the evolution of paired appendages. 相似文献
995.
JD Knudsen K Fuursted F Espersen N Frimodt-M?ller 《Canadian Metallurgical Quarterly》1997,41(9):1910-1915
The activities of glycopeptides against pneumococci were studied in vitro and in vivo. The MICs of two glycopeptides, vancomycin and teicoplanin, in different media against 10 strains of pneumococci with different susceptibilities to penicillin were determined. The MICs of teicoplanin were four times lower than those of vancomycin in Mueller-Hinton media supplemented with 5% blood, but the MICs were similar in mouse and human sera supplemented with 5% blood. The serum protein binding levels in mouse and human sera were 90% for teicoplanin in both and 25 and 35%, respectively, for vancomycin. The MICs for vancomycin and teicoplanin were only correlated in human serum (P < 0.001). The single doses giving protection to 50% of the animals in the mouse peritonitis model after a lethal challenge of pneumococci, the ED50s, were similar for vancomycin and teicoplanin, between 0.1 and 1 mg/kg of body weight for all 10 strains. The log ED50s were significantly correlated only to the log MICs of teicoplanin determined for mouse serum with 5% blood (P = 0.01) and to the log MICs of vancomycin determined by the E test (P = 0.03). Among the pharmacokinetic parameters analyzed at the ED50s, the most constant parameter was the time for which the drug concentration exceeded the MIC (T(>MIC)) when each drug was considered separately; however, when both drugs were considered together, the maximum concentration of drug in serum (Cmax) varied the least. This indicates that both these parameters are of importance for predicting the effect of the drugs. We conclude that the effect of glycopeptides was not influenced by the penicillin resistance of the pneumococci, either in vitro or in vivo, and that the superior activity of teicoplanin over that of vancomycin in vitro was abolished in vivo, an effect which probably was due to the high serum protein binding of teicoplanin. Both the pharmacokinetic parameters T(>MIC) and Cmax are important predicting the effect of glycopeptides, but the pharmacodynamics of glycopeptides are still not completely elucidated. 相似文献
996.
A retrospective literature survey (1980-1992) was conducted to chronicle the development of panic disorder treatment research. Based on a National Institute of Mental Health conference on assessment standardization in this area (Shear and Maser, 1994), the results and implications of the survey are presented in terms of eight domains of measurement recommended as essential for high quality research. 相似文献
997.
ML Skakkebaek B Georg JD Mikkelsen B Ottesen J Fahrenkrug 《Canadian Metallurgical Quarterly》1995,16(7):1287-1294
The expression of VIP precursor products: prepro-VIP(22-79), peptide histidine isoleucine (PHI), peptide histidine valine (PHV), prepro-VIP(111-122), VIP, prepro-VIP(156-170), and prepro-VIP mRNA in the anterior pituitary of estrogen-treated, ovariectomized rats, of ovariectomized controls, and of sham-operated controls was examined. Using radioimmunoassays based on antisera against each of the prepro-VIP sequences, we found that all sequences were expressed and markedly induced by estrogen, except PHI and PHV, which both were undetectable. By immunohistochemistry, it appeared that the number of cells immunoreactive for each of these sequences was increased in the estrogen-treated animals. However, PHI/PHV-immunoreactive cells could not be detected, despite the use of four different PHI antisera with different specificities. Estrogen treatment increased the prepro-VIP mRNA as judged by Northern blotting. In situ hybridization signals for both VIP mRNA and PHI mRNA were observed in few pituitary cells from control animals whereas strong positive signals were observed in a larger number of cells after estrogen treatment. The findings show that estrogen causes activation of the VIP gene expression in anterior pituitary cells, and that the absence of PHI and PHV probably is due to translational or posttranslational events. 相似文献
998.
Adverse reactions to drugs are well recognized as a cause of acute or chronic urticaria, and angio-oedema. Angiotensin-converting enzyme (ACE) inhibitors, used to treat hypertension and congestive heart failure, were introduced in Europe in the middle of the eighties, and the use of these drugs has increased progressively. Soon after the introduction of ACE inhibitors, acute bouts of angio-oedema were reported in association with the use of these drugs. We wish to draw attention to the possibility of adverse reactions to ACE inhibitors after long-term use and in patients with pre-existing angio-oedema. 相似文献
999.
PB Hoebeke JD Van Gool E Van Laecke J Vande Walle H Plancke 《Canadian Metallurgical Quarterly》1996,78(5):780-782
OBJECTIVE: To evaluate the incidence and significance of the urodynamic registration of an after-contraction in the bladder of children. PATIENTS AND METHODS: In a prospective study, 250 children with a non-neurogenic voiding dysfunction (132 girls and 118 boys) were assessed for the occurrence of after-contractions during their video-urodynamic examination, and any filling-phase dysfunction noted. Twenty children in whom an after-contraction was recorded underwent additional voiding cystometry with three pressure transducers in the bladder (two microtip and one external transducer connected to a fluid-filled catheter). RESULTS: Of the 250 children, an after-contraction was registered in 84 (63 girls and 21 boys). Eighty of these had a filling-phase dysfunction; 51 had detrusor instability, 16 a hypersensitive bladder, six a low and seven a high compliance. Only four showed a normal cystometric pattern during filling. In the 20 children who underwent further study, the after-contraction was confirmed as a detrusor contraction, as it was registered simultaneously on three transducers of two types in 10 children and on two microtip transducers in another 10 children. CONCLUSION: The after-contraction is a frequent occurrence in children with voiding dysfunction, is related to bladder instability and is a genuine detrusor contraction. 相似文献
1000.
Physical contact between human T lymphocytes and B lymphocytes is required for the induction of IgE production. In the present study, we examined the abilities of CD45RA+ and CD45RO+ human T cell subsets to provide help for IgE production by human peripheral blood B cells in the presence of IL-4. Purified peripheral CD45RA+ T cells are much better inducers of IgE synthesis than are CD45RO+ T cells. Activation of CD45RA+ T cells, but not CD45RO+ T cells, via the TCR/CD3 complex is sufficient to confer the ability to provide IgE help, suggesting that an inducible T cell surface molecule plays an important role in this system. The CD40 ligand, an inducible T cell surface molecule, is expressed at higher levels on CD45RA+ T cells as compared with CD45RO+ T cells following CD3-stimulation. Blocking of the CD40-CD40 ligand interaction in vitro by the addition of a soluble form of B cell CD40 Ag completely blocks IgE production induced by CD45RA+ T cells. Finally, the in vitro conversion of CD45RA+ T cells to the CD45RO+ phenotype is accompanied by a loss in the ability of these cells to express the CD40 ligand in response to anti-CD3 stimulation as well as a loss in their ability to provide IgE help. These results suggest that both CD45 subsets may play significant and distinct roles in the induction of IgE production under physiologic conditions: CD45RO+ T cells provide IL-4 and the CD45RA+ subset provides the second signal via the CD40 ligand. 相似文献