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991.
Detwiler T. C.; Odell T. T. JR.; McDonald T. P. 《The American journal of physiology》1962,203(1):107-110
992.
Seibert JJ; McCowan TC; Chadduck WM; Adametz JR; Glasier CM; Williamson SL; Taylor BJ; Leithiser RE Jr; McConnell JR; Stansell CA 《Radiology》1989,171(1):155-159
This study was conducted to determine if the resistive index (RI) could be used for the examination and follow-up of neonates with increased intracranial pressure. First, in a laboratory model with four mongrel dogs, RI was found to correlate linearly with cerebral perfusion pressure. Second, RI was studied in 57 healthy neonates and 285 neonates with abnormal clinical or head ultrasound findings. Average RI for healthy newborns was 75 +/- 10 and was inversely related to gestational age. RI in newborns with abnormal findings was uniformly elevated, but these values varied considerably and were not statistically different from normal values. Third, the RI was found to decrease significantly after patent ductus arteriosus ligation, tapping of subdural effusions, ventricular tapping (later cerebrospinal fluid shunting led to a further drop in RI), and ventriculoperitoneal shunting. Elevated RI indicates possible intra- or extracranial abnormality affecting cerebral blood flow. Doppler RI is valuable in following up neonates with abnormal or unstable conditions and in assessing the effectiveness of therapies to improve cerebral perfusion. 相似文献
993.
祁州漏芦蜕皮甾酮类化学成分的研究 总被引:14,自引:0,他引:14
从祁州漏芦[Rhaponticum uniflorum(L.)DC.]的根中,分离出三个蜕皮甾酮类化合物Ⅰ,Ⅱ,Ⅲ,其中Ⅱ根据UV,IR,MS,13CNMR,1HNMR,1H-1HCOSY,1H-1HNOESY,1H-13C COSY,及CD谱确定其结构为(20R,22R,24S)-2β,3β,11α,14α,20,22,24-heptahydroxy-5β-cholest-7-en-6-one,为一新化合物,命名为漏芦甾酮(rhaponfisterone)。化合物Ⅰ和Ⅲ分别鉴定为蜕皮甾酮(ecdysterone)和土克甾酮(turkesterone)。 相似文献
994.
995.
996.
Thirty eight children aged between 2 and 4 years with three or more episodes of wheezing were studied to evaluate the role of eosinophil inflammation and its relation to persistence of wheezing two years later. Serum eosinophilic cationic protein, total eosinophil count, total IgE, skin prick test, and clinical features were evaluated at visit 1. Two years later at a second clinical evaluation the children were separated into two groups: group 1, those with persistent wheezing (n = 20); group 2, those who had been asymptomatic over the past six months (transient wheezing) (n = 18). Mean (SEM) eosinophilic cationic protein at visit 1 was higher in group 1 than in group 2 (29.63 (5.16) v 14.42 (2.77) micrograms/l), and the probability of continuing wheezing at age 5 years was greater in children with values > or = 20 micrograms/l at visit 1 than in those with lower values (relative risk = 2.88, 95% confidence interval 1.42 to 5.87, p < 0.001). Eosinophil inflammation is present from the beginning of the disease in the children who are going to continue with wheezing at age 5 years. The measurement of serum eosinophilic cationic protein may help in evaluating which wheezing infants are going to continue with asthma in the future. 相似文献
997.
Lamas JR; Brooks JM; Galocha B; Rickinson AB; Lopez de Castro JA 《International immunology》1998,10(3):259-266
The effect of HLA-B27 polymorphism on antigen presentation was analysed by
comparing the binding of three Epstein-Barr virus-derived peptide epitopes
to HLA-B27 subtypes with their immunogenicity and antigenicity in the
context of these subtypes. The effect of altering the major anchor residue
Arg2 on binding or on recognition by peptide-specific cytotoxic T
lymphocytes (CTL) was also examined. The three peptides bound significantly
to all the B*2701-B*2706 subtypes. This did not correlate with the peptides
being immunogenic or recognized by specific CTL in the context of only
particular subtypes. In addition, of the three viral epitopes tested, those
that were immunogenic in B*2702- or B*2705-restricted responses bound to
these subtypes less efficiently than one peptide that was immunogenic only
in the B*2704 context. Thus, among several potentially immunogenic peptides
from the same virus, the antiviral response is not necessarily directed
against the one that binds best to the restricting subtype. These results
indicate that HLA- B27 polymorphism influences antigen presentation in ways
other than simply peptide affinity. Synthetic analogues lacking the
canonical Arg2 motif of HLA-B27-bound peptides, even when binding much
worse to the restricting subtype, were recognized equally by CTL specific
for the parental peptide. This indicates that Arg2 is not required to
maintain the structure of the epitope. The implications of these results
for pathogenetic models of HLA-B27-associated disease are discussed.
相似文献
998.
Dynamic regulation of gastric autoimmunity by thyroid hormone 总被引:1,自引:0,他引:1
999.
Gastroesophageal reflux disease(GERD) usually requires long-term therapy. Treatment strategies include proton pump inhibitor (PPI) or H2receptor-antagonists (H2RA), or prokinetic agents.
OBJECTIVE: A decision tree analytic model for comparing economic and clinical outcomes of GERD treatment strategies using continuous or intermittent therapy with PPI, H2RA, or prokinetic agents was developed.
METHODS: Two decision tree models were constructed. One compared four continuous drug therapies; the other compared four intermittent drug treatments. Base values for heal rates and relapse frequencies were determied by analysis of published clinical data. Costs were drug, physician visit, endoscopy, and surgery costs. Clinical outcomes (percent of patients asymptomatic) and economic outcomes (direct costs) were determined at 12 months.
RESULTS: The four continuous treatment strategies resulted in 99–100% asymptomatic patients at 1 year whereas the four intermittent strategies resulted in 76–80% asymptomatic patients at 1 year. At 1 year, the costs per asymptomatic patient, for continuous treatment strategies, were $1069, $1083, $1164, and $1193 for omeprazole 20 mg daily initially followed by omeprazole 10 mg, omeprazole 20 mg, or ranitidine 300 mg daily, or ranitidine 300 mg daily continously, respectively, and for intermittent strategy, were $1299, $1304, $1353, and $1455 for omeprazole 20 mg, cisapride 40 mg daily followed by omeprazole for failures, ranitidine 300 mg daily followed by omeprzole for failures, and ranitidine 300 mg daily followed by ranitidine 600 mg daily. Sensitivity analyses showed omeprazole cost and healing rate to have the greatest impact on the cost of treatment.
CONCLUSIONS: These GERD decision tree analytic models are useful tools for comparing economic and clinical outcomes of drug treatment strategies over a wide range of costs and clinical efficacies. 相似文献
OBJECTIVE: A decision tree analytic model for comparing economic and clinical outcomes of GERD treatment strategies using continuous or intermittent therapy with PPI, H2RA, or prokinetic agents was developed.
METHODS: Two decision tree models were constructed. One compared four continuous drug therapies; the other compared four intermittent drug treatments. Base values for heal rates and relapse frequencies were determied by analysis of published clinical data. Costs were drug, physician visit, endoscopy, and surgery costs. Clinical outcomes (percent of patients asymptomatic) and economic outcomes (direct costs) were determined at 12 months.
RESULTS: The four continuous treatment strategies resulted in 99–100% asymptomatic patients at 1 year whereas the four intermittent strategies resulted in 76–80% asymptomatic patients at 1 year. At 1 year, the costs per asymptomatic patient, for continuous treatment strategies, were $1069, $1083, $1164, and $1193 for omeprazole 20 mg daily initially followed by omeprazole 10 mg, omeprazole 20 mg, or ranitidine 300 mg daily, or ranitidine 300 mg daily continously, respectively, and for intermittent strategy, were $1299, $1304, $1353, and $1455 for omeprazole 20 mg, cisapride 40 mg daily followed by omeprazole for failures, ranitidine 300 mg daily followed by omeprzole for failures, and ranitidine 300 mg daily followed by ranitidine 600 mg daily. Sensitivity analyses showed omeprazole cost and healing rate to have the greatest impact on the cost of treatment.
CONCLUSIONS: These GERD decision tree analytic models are useful tools for comparing economic and clinical outcomes of drug treatment strategies over a wide range of costs and clinical efficacies. 相似文献
1000.