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61.
Familial and sporadic hyperinsulinism: histopathologic findings and segregation analysis support a single autosomal recessive disorder 总被引:4,自引:0,他引:4
P S Thornton A E Sumner E D Ruchelli R S Spielman L Baker C A Stanley 《The Journal of pediatrics》1991,119(5):721-724
We evaluated the possible genetic contribution to hyperinsulinism in a series of patients seen during the past 15 years. Of 26 families, 5 (19%) had more than one child affected (multiplex family). There were no apparent differences between patients in the 5 multiplex and 21 simplex families, clinically, biochemically, or on histologic examination of the pancreatic specimens. The families studied had a total of 63 offspring; the 26 index patients had 37 siblings, 6 of whom were affected. After four patients with hyperinsulinism caused by adenoma were excluded from the study, segregation analysis was carried out to test the data for agreement with results expected if familial and isolated hyperinsulinism represented a single disease with recessive mode of inheritance and a segregation ratio of 0.25. Excellent agreement was found between the observed number of affected siblings (20) and the expected number (19.65), with a segregation ratio of 0.254. The results were consistent with the hypothesis that in most or all cases, hyperinsulinism is inherited as an autosomal recessive disease. There was no evidence of distinct familial and sporadic types. 相似文献
62.
Role of substance P in several models of bladder inflammation 总被引:1,自引:0,他引:1
Judith Luber-Narod Tammy Austin-Ritchie Carl Hollins III Mani Menon Rajwant K. Malhotra Stephen Baker Robert E. Carraway 《Urological research》1997,25(6):395-399
Substance P (SP) is a peptide found in the sensory nervous system which has multiple biologic effects including stimulation of muscle contraction, pain nociception, immune cell functions, plasma extravasation and a constellation of inflammatory effects. Here we investigate the role of SP in several animals models of bladder inflammation. Using the female Lewis rat, inflammation was induced using either xylene, lipopolysaccharide (LPS) or polyinosinic-polycytidylic acid (polyIC). Inflammation occurred rapidly (4 h) and was maintained in each model for at least 7 days. Each of these protocols decreased the bladder content of immunoreactive SP by approximately 50%, suggesting enhanced release. There was no change in the urinary frequency of these animals over 3 weeks, suggesting that urinary frequency changes are not mediated by acute inflammation. We also found that the SP receptor (NK1) antagonist, (?)CP96345, was unable to block the inflammation produced by polyIC, suggesting that SP is not an obligatory mediator of immune cell stimulation in this model. 相似文献
63.
Head injuries incurred by children and young adults during informal recreation. 总被引:1,自引:1,他引:0
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S P Baker C Fowler G Li M Warner A L Dannenberg 《American journal of public health》1994,84(4):649-652
To examine injuries related to playground equipment, children's vehicles, roller skates, and skateboards, 1991 data on emergency room patients younger than 25 years in the Consumer Product Safety Commission's 91 surveillance hospitals were used. Head injury was the primary diagnosis for an estimated 58,480 patients, exceeding the total number of head injuries to bicyclists younger than 25 years. The head injury rate decreased with age. The large number and high rate of head injuries in children involved in a variety of recreational activities suggests the value of multipurpose helmets. 相似文献
64.
In order to compare an acceleromyograph (TOF-GuardTM ) with a mechanomyograph (Grass FT03), the dose–response relationship of rocuronium was simultaneously determined in both arms of 15 children aged 3–11 years during anaesthesia with thiopentone, alfentanil and nitrous oxide. Three subgroups of five children received rocuronium 120, 180 or 240 μg.kg−1 randomly. The effective doses to produce 50% and 95% depression of the first twitch of the train-of-four determined by acceleromyography were 206 and 337 μg.kg−1 , respectively, while these values determined by mechanomyography were 151 and 331 μg.kg−1 , respectively. The dose–response curve obtained by acceleromyography was steeper and shifted to the right compared with that obtained by mechanomyography (p < 0.0001). The difference between the effective dose producing 50% twitch depression determined by the two devices was highly significant (p < 0.0001). In 13 out of 15 children, the acceleromyograph control train-of-four ratio was significantly greater than unity. Although there was a good correlation ( r = 0.85) between simultaneous pairs of measurements of neuromuscular block, the acceleromyograph exhibited a bias of −25% relative to the mechanomyograph with wide limits of agreement (−62 to +12%). We conclude that acceleromyographic and mechanomyographic measurements should not be used interchangeably when determining the potency of muscle relaxants. 相似文献
65.
The authors presented a new posterior beam-stop (PBS) technique for measuring the ratio of scattered to total-detected photon flux (scatter fraction) in a radiographic examination while preserving the diagnostic quality of the image. The scatter measurement was made using a standard imaging geometry with both beam stops and an additional x-ray detector placed behind the standard imaging detector. This PBS geometry differs from the standard beam-stop (SBS) technique for scatter measurement. With SBS, a beam-stop shadow appears on the image. To evaluate the PBS technique, scatter fraction measurements were performed on an anatomic phantom using both the PBS and SBS techniques. When compared with the standard technique, PBS provided accurate estimation of scatter fractions. Since the measurement can be performed without degrading a standard clinical radiographic examination, the PBS technique allows simultaneous acquisition of scatter measurements from human patients in combination with a standard radiographic examination. 相似文献
66.
J Saunders M Cassidy S B Freedman E A Harley L L Iversen C Kneen A M MacLeod K J Merchant R J Snow R Baker 《Journal of medicinal chemistry》1990,33(4):1128-1138
Recent clinical studies on Alzheimer's patients have implied that only agents displaying high efficacy at the cortical muscarinic receptor have yielded encouraging results. This paper describes the design, synthesis, and biochemical characterization of novel quinuclidine-based muscarinic agonists which can readily penetrate into the central nervous system and which are capable of displaying high efficacy at cortical sites. With use of a biochemical assay capable of measuring receptor affinity and predicting cortical efficacy, it has been discovered that an oxadiazole ring and related heterocycles can function as bioisosteric replacements for the ester moiety found in several known muscarinic ligands. Within this series there exist compounds which span the efficacy range from high-efficacy agonist through partial agonists to antagonists with affinity comparable or superior to that of classical quaternary ammonium ligands. Consistent with recent molecular biology studies, structure-activity trends are interpreted in terms of separate binding sites for agonists and antagonists with H-bonding interactions characterizing agonist behavior and lipophilic binding characterizing antagonist behavior. Thus the aminooxadiazole moiety has structural features which are optimized for an agonist profile. 相似文献
67.
Liver transplantation, including the concept of reduced-size liver transplants in children. 总被引:4,自引:1,他引:3
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C E Broelsch J C Emond J R Thistlethwaite P F Whitington A R Zucker A L Baker P F Aran D A Rouch J L Lichtor 《Annals of surgery》1988,208(4):410-420
Since the establishment of a clinical program in liver transplantation in 1984, 162 liver transplants have been performed in 131 patients (78 adults, 53 children). The patient mortality rate while waiting for a suitable organ has been 8% for adults and only 4% for children (25-46% reported in the literature). The low pediatric mortality is a result of the use of reduced-size liver transplants. A total of 14 procedures have been performed in recipients whose clinical condition was deteriorating and for whom no full-size graft could be located. Of 14 children, 13 were less than 3 years of age. Patient survival is 50%, comparable to survival of high-risk recipients of full-size livers. Using reduced-size liver grafting in a transplant program can lower mortality for children awaiting a transplant by overcoming size disparity. Reduced-size liver grafting will allow more effective use of donor resources and provide a potential avenue of research for organ splitting and living related donation. 相似文献
68.
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70.
Kate Windridge Carolyn Tarrant George K Freeman Richard Baker Mary Boulton Janet Low 《The British journal of general practice》2004,54(502):364-366
We report an analysis of the qualitative phase of a study of patients' and carers' views of primary care services, focusing on their experiences of access to face-to-face general practitioner (GP) consultations during the period when new access policies were being implemented. Practices interpreted the new policy in various ways; restricted interpretations, including restriction of access to telephone booking, could cause distress to patients. Patients and carers welcomed flexible interpretations of the policy that offered choice, such as a choice of GP, or of booking in advance. 相似文献