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981.
de Boer A; Schroder C; Reddingius R; Willems H; Monnens L 《Nephrology, dialysis, transplantation》1998,13(9):2348-2350
Background: The passage of proteins across the
glomerular filtration barrier is mainly determined by the size of the
protein. In nephrotic syndrome (NS) the glomerular permselectivity is
affected, causing proteinuria. Some authors suggest the existence of a
generalized basement membrane defect. The permeability characteristics of
the peritoneal basement membrane in children with NS are not known.
Methods: The transperitoneal transport of proteins
with a different molecular weight ({beta}2-microglobulin MW 11 800 D,
albumin MW 69 000 D, IgG MW 160 000 D, and &agr;2-macroglobulin MW 820
000 D) was studied in a study group (group A) consisting of six stable
nephrotic children (three with glomerulosclerosis and three with congenital
nephrotic syndrome, one of them with mesangial sclerosis) and compared to a
control group (group B) consisting of eight stable children on peritoneal
dialysis. After a dwell of 6 h with Dianeal 1.36% dialysate and serum
samples were collected. For each patient the dialysate to plasma (D/P)
ratio of the four proteins were calculated. The D/P ratios of the nephrotic
patients in group A were compared to the D/P ratios of the patients in the
control group B. Data were expressed as mean ±SD.
Results: The values for the D/P ratios (in percentage)
of {beta}2-microglobulin, albumin, IgG and &agr;2-macroglobulin in
group A were 19.6±9.9, 2.7±1.7, 1.6±0.9,
and 0.5±0.4, compared to 24.9±10.2,
4.0±2.3, 2.2±1.2, and 0.7±0.3 in the
control group B. The ratios were plotted against MW on a double logarithmic
scale. In all patients a linear relationship between molecular weight and
D/P ratio of the proteins was obtained. The D/P ratios of the study group
did no differ significantly from the control group.
Conclusion: We conclude that the size selectivity of
the capillary permeability is not affected in the peritoneal membrane in
children with NS due to glomerulosclerosis and congenital nephrotic
syndrome. 相似文献
982.
Randomised trial comparing the upright and supine positions for the second stage of labour 总被引:2,自引:1,他引:1
P. R. de Jong Senior Specialist R. B. Johanson Senior Lecturer P. Baxen Chief Professional Nurse V. D. Adrians Senior Professional Nurse S. van der Westhuisen Lecturer P. W. Jones Professor 《BJOG : an international journal of obstetrics and gynaecology》1997,104(5):567-571
Objective To assess the maternal and neonatal effects of upright compared with recumbent positions during delivery, in terms of defined outcome variables.
Design A randomised controlled trial.
Setting St Monica's Nursing Home, a midwife based maternity unit in Cape Town, South Africa.
Participants Five hundred and seventeen women of low obstetrical risk assigned to deliver at the nursing home.
Results The trial showed that women who adopted the upright posture for delivery experienced less pain, perineal trauma and fewer episiotomies than those who delivered in the supine position.
Conclusion The data suggest that in women of low obstetrical risk, choice of posture during delivery may be encouraged. 相似文献
Design A randomised controlled trial.
Setting St Monica's Nursing Home, a midwife based maternity unit in Cape Town, South Africa.
Participants Five hundred and seventeen women of low obstetrical risk assigned to deliver at the nursing home.
Results The trial showed that women who adopted the upright posture for delivery experienced less pain, perineal trauma and fewer episiotomies than those who delivered in the supine position.
Conclusion The data suggest that in women of low obstetrical risk, choice of posture during delivery may be encouraged. 相似文献
983.
Endoscopic Sphincterotomy and Biliary Drainage in Patients with Cholangitis Due to Common Bile Duct Stones 总被引:13,自引:0,他引:13
984.
Summary We report two cases of Creutzfeld-Jakob disease with clusters of giant collagen fibers. To our knowledge, these abnormally large collagen fibers have never been described in patients with degenerative diseases of the central nervous system. The significance of the formation of such plaque-like large collagen fibers has as yet not been elucidated. It is felt that these represent a product of the degenerative process.Presented in part at the 68th Annual Meeting of the American Association of Neuropathologists, St. Louis, Missouri, June 18–21, 1992 相似文献
985.
Introns and gene evolution 总被引:5,自引:0,他引:5
Sandro J. de Souza Manyuan Long & Walter Gilbert 《Genes to cells : devoted to molecular & cellular mechanisms》1996,1(6):493-505
In one scenario of gene evolution, exon shuffling has a fundamental role in increasing gene diversity. As DNA sequences accumulate in the databases, the picture of the intron/exon structures of genes becomes more and more clear. We discuss in this review some features of this picture that suggest that introns have been present since the early stages of evolution, and that exon shuffling was a fundamental process in the construction of ancient as well as modern genes. 相似文献
986.
A validity study of the Brazilian version of the 15-item Short Psychiatric Evaluation Schedule (SPES), included in the mental health assessment of Older Americans Resources and Services (OARS), designed to detect psychiatric disorders in the elderly, against the "caseness" criterion suggested by Cooper and Schwarz was carried out with a community sample, as part of a survey to study health and living conditions of the elderly in a large urban center of a developing country, S?o Paulo, Brazil. The screening questionnaire was completed by 292 subjects, and 91 were selected for the psychiatric interview. The validity coefficients were as follows: sensitivity 61%, specificity 89%, positive predictive value 66%, negative predictive value 87% and misclassification rate 18%. A discriminant analysis using a stepwise procedure was then applied to select the best item discriminators of the screening questionnaire. The best set of discrimination comprised six items leading to the following validity coefficients: sensitivity 82%, specificity 77%, positive predictive value 58%, negative predictive value 92% and misclassification rate 21%. The possible factors related to false positive and false negative responses on the screening are discussed. 相似文献
987.
This report describes the laparoscopic features of two patients with serosal eosinophilic gastroenteritis. In one case only hyperemia of the peritoneal serosa was found. In the other the laparoscopic picture resembled peritoneal carcinomatosis. We show that laparoscopy and peritoneal biopsy may permit diagnosis of the disease without the need for laparotomy. 相似文献
988.
A Giorgio P Amoroso G Francica G de Stefano P Fico G Lettieri L Tarantino L Finelli F Fiorentino P Pierri 《Gastrointestinal radiology》1988,13(4):336-340
To clarify the therapeutic role of echo-guided percutaneous puncture (EPP) in management of amebic liver abscess, 20 patients (24 abscesses) received metronidazole plus EPP. Fluid was aspirated through Chiba needles under real-time sonographic guidance so as to reduce cavity size to less than 3 cm. Not more than two EPPs were necessary in the majority of cases and no complication followed the procedure. This scheme resulted in a shortening of time of both hospitalization (less than or equal to 20 days) and liver lesion healing as assessed by ultrasound (less than or equal to 4 months). It is concluded that EPP is a valuable and safe therapeutic tool for hepatic amebic abscess. 相似文献
989.
Summary Fourteen patients with Ph'-chromosome positive chronic myelogenous leukemia (CML) in first chronic phase were treated with recombinant interferon-2c. Interferon-2c 5 to 10×106 units s.c. was given for 12 weeks as an induction therapy. Maintenance treatment consisted of interferon-2c 5 × 106 units twice weekly s.c.. Two patients (14%) attained a complete clinical remission and 6 (43%) a partial remission, 3 of whom developed progressive disease during maintenance therapy. A complete disappearance of Ph'-chromosome was achieved in 1 patient. All patients had a more than 45% initial decline of the leukocyte count. Four out of ten patients with an initially enlarged spleen demonstrated reduction in spleen size. Influenza-like symptoms, anorexia, nausea, weight loss and fatigue were common side effects. Interferon-alpha is active in CML but additional clinical investigations are warranted to assess more precisely the therapeutic value of the interferons in this disease. 相似文献
990.
Dassarma S Halladay JT Jones JG Donovan JW Giannasca PJ de Marsac NT 《Proceedings of the National Academy of Sciences of the United States of America》1988,85(18):6861-6865
Gas vesicle-deficient mutants of Halobacterium halobium arise spontaneously at high frequency (about 1%). The mutants are readily detected, forming translucent colonies on agar plates in contrast to opaque wild-type colonies. To investigate the mechanism of this mutation, we recently cloned a plasmid-encoded gas vesicle protein gene, gvpA, from H. halobium. In the wild-type NRC-1 strain the gvpA gene is encoded by a multicopy plasmid of approximately 150 kilobase pairs (kb). We have now characterized 18 gas vesicle-deficient mutants and 4 revertants by phenotypic and Southern hybridization analyses. Our results indicate that the mutants fall into three major classes. Class I mutants are partially gas vesicle-deficient (Vac(delta-)) and unstable, giving rise to completely gas vesicle-deficient (Vac(-)) derivatives and Vac(+) revertants at frequencies of 1-5%. The restriction map of the gvpA gene region in class I mutants is unchanged but the gene copy number is reduced compared to the Vac(+) strains. Class II mutants can be either Vac(delta-) or completely Vac(-) but are relatively stable. They contain insertion sequences within or upstream of the gvpA gene. A Vac(-) class II mutant, R1, contains the 1.3-kb insertion sequence, ISH3, within the gvpA gene, whereas four Vac(delta-) class II mutants contain other insertion sequences upstream of the gene. Class III mutants are stable Vac(-) derivatives of either the wild-type or class I mutants and have no detectable copies of the gvpA gene. Based on these results, we discuss the mechanisms of gas vesicle mutations in H. halobium. 相似文献