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251.
252.
Rudolf Bumm Carsten Emde David Armstrong Peter Bauerfeind ré L. Blum 《Neurogastroenterology and motility》1990,2(3):216-223
This study describes the validation of a computer program for automated analysis of ambulatory 24-hour two-channel esophageal manometry. The program's ability to characterize contractions and to calculate their duration and amplitude was validated against manual evaluation. An independent reference standard for the identification and classification of contractions was established by submitting representative recordings to a group of 14 experts in upper gastrointestinal motility; the program's ability to identify and classify contractions was then validated against the majority verdict of the experts. The results show an excellent correlation between the manual and computer evaluations of both contraction amplitude (p = 0.9957) and duration (p = 0.8241). The concordance between the experts was also excellent: 97 (72%) of 135 pressure events were classified identically by 12 or more experts. Computer-aided manometry analysis (CAMA) had a sensitivity of 98.9% and a specificity of 93.5% for the detection of contractions, with sensitivities of 94.7% and 84.4% and specificities of 94.9% and 94.2% for the classification of propagated and nonpropagated contractions, respectively. 相似文献
253.
Loflin TG; Simeone JF; Mueller PR; Saini S; Stark DD; Butch RJ; Brady TJ; Ferrucci JT Jr 《Radiology》1985,157(2):457-459
Fifty-three samples of gallbladder bile were obtained at the time of cholecystectomy from patients with the clinical diagnosis of acute or chronic cholecystitis. Five bile samples from patients with clinically normal gallbladders also were obtained. Proton magnetic resonance (MR) relaxation times, protein content, and water content were determined for the bile samples, and the data were grouped according to pathologic diagnosis, which disclosed 11 cases of acute cholecystitis, 41 cases of chronic cholecystitis, and six normal gallbladders. There was no significant difference in the mean T1 and T2 values between the groups with acute and chronic cholecystitis. Patients with chronic cholecystitis were found to have more concentrated bile than those with acute cholecystitis. Protein content varied widely within both groups of patients. We conclude that T1 and T2 relaxation times do not reliably differentiate acute from chronic cholecystitis. 相似文献
254.
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256.
Summary The increasing knowledge of the structure and function of macromolecular carbohydrate-protein compounds (glycoproteins) has led to an increase in interest in these molecules in biology and especially in medicine in recent years. In saliva the largest part of the glycoproteins is constituted by the mucins. Salivary mucins exhibit very high molecular weight, have a high percentage of carbohydrate (approx. 70%) in the form of fucose, N-acetylglucosamine, N-acetylgalactosamine, galactose mannose and N-acetylneuraminic acid. They have a negative charge due to N-acetylneuraminic acid and sulphate residues, which together with the high molecular weight of these glycoproteins leads to characteristic viscous properties.The most important mucin properties which play a role in the upper respiratory and alimentory tract will be presented, especially the viscous character with respect to lubricative functions, the protection of mucous surfaces against microorganisms and other agents.A few physiological and pathological mucin analysis of human saliva and its method of analysis will be presented.
Mit Hilfe der Deutschen Forschungsgemeinschaft 相似文献
Mit Hilfe der Deutschen Forschungsgemeinschaft 相似文献
257.
258.
259.
Human epididymal secreted protein CD52 on ejaculated spermatozoa: correlations with semen characteristics and the effect of its antibody 总被引:1,自引:2,他引:1
CD52 is a glycosylphosphatidylinositol-anchored glycoprotein secreted by
the epididymis where it is incorporated into sperm membranes. The antigen
is common to spermatozoa and lymphocytes, and its role is not known.
Quantitative analysis using immunostaining with the monoclonal antibody
CAMPATH-1G and flow cytometry indicated positive signals from approximately
80% of viable, washed ejaculated spermatozoa. Staining intensity increased
after capacitation overnight, and decreased after short incubation with
high density lipoprotein. After incubation of Percoll-washed spermatozoa
with CAMPATH-1G, motility was reduced from 83 to 74% after 5 min and from
73 to 52% after 3.5 h. Swimming velocities were reduced by approximately
30% and linearity by 15% in 5 min, but no further decreases were observed
over 3.5 h. After 20 min incubation with the antibody, cell viability was
decreased by 10 and 20% in freshly washed and capacitated spermatozoa
respectively. Comparison of fertile and infertile patients revealed no
difference in the percentages of immunostained spermatozoa or in staining
intensity and there were no differences in sperm labelling between
normozoospermia and teratozoospermia. Compared with normozoospermia,
percentages of stained spermatozoa were lower by 20 and 27% in
asthenozoospermia and oligozoospermia respectively, whereas staining
intensity in asthenozoospermia was less than half that in oligozoospermia.
The correlation of percentages of stained spermatozoa with percentages of
motile cells suggests the involvement of epididymal CD52 in the maturation
of sperm function.
相似文献
260.
R. Bumm 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》1927,202(5-6):289-303
Ohne Zusammenfassung 相似文献