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1.
Theodore Berk MD Robert F. Crochelt BA Dr. Steven R. Peikin MD 《Digestive diseases and sciences》1986,31(5):502-505
Obese Zucker rats are less responsive than their lean littermates to the effects of cholecystokinin-octapeptide on satiety and pancreatic growth and exocrine function. We hypothesized that the hyperphagia observed in obese Zucker rats may be caused by a decreased pyloric contractile response to cholecystokinin, resulting in an increased rate of gastric emptying, decreased postprandial gastric distention, and thus decreased satiety. Pyloric muscle strips from six obese Zucker rats and six lean littermates were mounted in separate tissue baths and isometric contraction was measured in response to acetylcholine and cholecystokinin-octapeptide. The dose-response curves for acetylcholine-and cholecystokinin-octapeptide-stimulated pyloric muscle contraction were similar for both the obese and the lean rats. (For cholecystokinin, D50 obese=4.0±0.6 nM, D50 lean=3.4±0.2 nM;P=0.16). We conclude that the decreased satiety response to cholecystokinin-octapeptide observed in obese Zucker rats is not secondary to a decreased pyloric responsiveness to cholecystokinin.This work was supported by NIH grant AM28303-03. 相似文献
2.
Safety and efficacy of bariatric surgery: Longitudinal Assessment of Bariatric Surgery 总被引:3,自引:0,他引:3
Steven H. Belle Ph.D. M.Sc.Hyg. Paul D. Berk M.D. Anita P. Courcoulas M.D. M.P.H. F.A.C.S. David R. Flum M.D. M.P.H. F.A.C.S. Carolyn W. Miles Ph.D. James E. Mitchell M.D. Walter J. Pories M.D. F.A.C.S. Bruce M. Wolfe M.D. F.A.C.S. Susan Z. Yanovski M.D. Longitudinal Assessment of Bariatric Surgery Consortium Writing Group 《Surgery for obesity and related diseases》2007,3(2):116-126
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The authors have examined the incidence of intrauterine growth retardation at a country level for the first time both in local and international aspect. Using the nomenclature of NDN-system they have found the frequency of WL-(proportional) retardation 7.95% and that of N-(disproportional) retardation 5.99%. They show incidence of retardation from county to county, as well. Examining the correlation between retardation and perinatal mortality they've stated that while the frequency of still-birth among the average developed and proportionally nutrified fetus is 0.34% and the frequency of perinatal mortality among them is 1.23%, that of the N-retardated newborns is 0.88% and 2.08%, respectively, and that of the WL-retarded is higher than the latter: 2.03% and 3.90% respectively. Regarding the incidence and mortality ratio among the two types of retardation the difference is significant. 相似文献
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The usefulness of the enzyme multiplied immunoassay quantitative single test (EMIT QST) gentamicin assay was assessed for gentamicin analysis in patient sera. The EMIT QST reagents are in powder form in a single, premeasured vial and are run on a thermoregulated sample processor that controls mixing and timing steps. The results of the clinical evaluation showed that the standard curve was stable throughout a 26-day study period. Within-run precision on 20 replicates at 4.0 micrograms/ml yielded a coefficient of variation (CV) of 5.6%; between-run precision on 66 analyses at 6.0 micrograms/ml over a 152-day period yielded a CV of 4.0%. Mean recovery through the range of the standard curve with 10 spiked patient samples was 102%. Comparative analysis with radioimmunoassay of 95 patient samples showed a correlation of 0.97, with y = 0.93x - 0.03. It was concluded that the EMIT QST gentamicin assay is an appropriate, rapid methodology for patient gentamicin analysis. 相似文献
7.
In vivo studies with two phospholipase C fractions from Pseudomonas aeruginosa. 总被引:2,自引:6,他引:2
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Two phospholipase C fractions were detected in culture supernatants from Pseudomonas aeruginosa ATCC 19660, PAO1, and D10C by preparative polyacrylamide gel electrophoresis. Both hemolytic fractions from strain ATCC 19660 were isolated by polyacrylamide gel electrophoresis and were found to cause paralysis, death, dermonecrosis, footpad swelling, and vascular permeability in mice. In vivo toxicity was directly associated with enzymatic activity. 相似文献
8.
Selective medium with DNase test agar and a modified toluidine blue O technique for primary isolation of Branhamella catarrhalis in sputum. 总被引:1,自引:2,他引:1
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J L Soto-Hernandez D Nunley S Holtsclaw-Berk S L Berk 《Journal of clinical microbiology》1988,26(3):405-408
A selective medium with DNase test agar and incorporating vancomycin (10 micrograms/ml), trimethoprim (8 micrograms/ml), and amphotericin B (2 micrograms/ml) supported the growth of 305 Branhamella catarrhalis isolates. A modified toluidine blue O technique was used after 48 h of incubation in CO2 to overlay suspected B. catarrhalis colonies. A metachromatic color change was observed in 15 min, indicating DNase production. In 200 unselected sputum samples of hospitalized patients, this method was compared with routine microbiologic procedures; 31 B. catarrhalis isolates were recovered with the method, compared with 22 isolated from the clinical laboratory. This medium will be particularly useful for culture of sputum, which shows inflammatory cells and gram-negative diplococci on Gram-stained smears. 相似文献
9.
R A Berk 《Journal of clinical psychology》1983,39(1):133-136
Examined the research on WISC-R profile analysis germane to the differential diagnosis of learning disabled children in relation to several methodological problems that concern score use and interpretation. The evidence based on Bannatyne's (1974) recategorization of the subtests indicates a Spatial greater than Conceptual greater than Sequencing pattern of performance for learning disabled children. The application of this evidence of group characteristics to the individual child is problematic. The trend is not consistent. In addition, the interpretation of the individual profile is complicated by the unreliability of a few of the subtests, the unreliability of subtest difference scores, the unreliability of Bannatyne category difference scores, and the invalidity of the difference scores for discriminating between learning disabled and other children. It was recommended that clinicians not use the WISC-R profile to diagnose specific learning disabilities. Instead, the analysis may have greater utility in the prevention and remediation of learning problems, especially at the preschool level. 相似文献
10.
Characterization of Pseudomonas aeruginosa adherence to mouse corneas in organ culture. 总被引:1,自引:5,他引:1
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The present study was designed to obtain further information on the nature of the corneal macromolecule(s) to which Pseudomonas aeruginosa adheres and how adherence might be prevented. Scarified adult mouse corneas in organ culture were treated with trypsin or lipase to determine whether the receptor molecule(s) was protein or lipid in nature. Trypsin (20 micrograms/ml) treatment of the cornea for 5 min had no significant effect on bacterial adherence, and longer periods of enzyme exposure resulted in extensive surface cell lysis. In contrast, lipase treatment (50,000 U/ml) for 1 h caused little visible cell lysis and significantly reduced bacterial adherence. To test further the lipid nature of the receptor, a highly purified monosialoganglioside (GM1) preparation (500 micrograms/ml) was used to preincubate (1 h) the cornea prior to bacterial application, and this also inhibited bacterial adherence. Similar corneal treatment with gangliotetraosylceramide (asialo GM1) (500 micrograms/ml) had little effect on ocular bacterial binding. Premixing of the bacterial inoculum with GM1 prior to corneal application had no significant effect on inhibiting bacterial binding, but similarly premixing the bacterial inoculum with asialo GM1 transiently decreased adherence. Lastly, premixing of the bacterial inoculum or preincubation of corneas with fibronectin (500 micrograms/ml for 1 h) both decreased bacterial adherence. These findings provide evidence that the receptor-adhesin interactions of P. aeruginosa at the ocular surface in organ culture are complex, involve a glycolipid moiety, and may be blocked by a ganglioside containing at least one sialosyl residue or by fibronectin, which may bind to membrane-associated gangliosides. 相似文献