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91.
Previously, we showed that 12-O-tetradecanoyl phorbol 13-acetate (TPA), an activator of protein kinase C, is a mitogen for fetal human definitive zone adrenocortical cells in culture. In the present experiments, TPA inhibited forskolin-stimulated cortisol, dehydroepiandrosterone (DHEA), and dehydroepiandrosterone sulfate (DHEAS) synthesis, and enhanced forskolin-stimulated progesterone and corticosterone synthesis. These changes in the pattern of steroidogenesis were shown to result from changes in enzyme activities after forskolin treatment. TPA increased forskolin-stimulated 3 beta-hydroxysteroid dehydrogenase (3 beta-HSD) 2-fold, while depressing forskolin-stimulated 17 c-hydroxylase to basal values DHEA sulfotransferase increased 3-fold on transfer of human adrenocortical cells from serum-containing to defined, serum-free medium; TPA inhibited this increase. Experiments in which TPA was added at various times during the time course of forskolin stimulation of 17 alpha-hydroxylase showed that TPA prevents the increase in the level of 17 alpha-hydroxylase, and does not have a direct inhibitory effect on 17 alpha-hydroxylase activity. TPA also inhibited stimulation of 17 alpha-hydroxylase by cAMP analogs, indicating that the inhibition of 17 alpha-hydroxylase by TPA is not due to an effect on adenylate cyclase. Previous experiments have shown that stimulation of intracellular cAMP is sufficient for androgen synthesis by the human adrenocortical cell, under defined, serum-free conditions, and that its high rate of androgen synthesis likely results from the relative levels of 3 beta-HSD, 17 alpha-hydroxylase, and DHEA sulfotransferase in the cell. Enzyme induction by cAMP results in increased production of both androgens and glucocorticoids, whereas activation of protein kinase C changes the balance of enzymes, resulting in increased non-17 alpha-hydroxylated steroid synthesis and decreased androgen and cortisol biosynthesis. 相似文献
92.
WS Lee PJ McKiernan J de Ville de Goyet MS Tanner PR John 《Acta paediatrica (Oslo, Norway : 1992)》2001,90(11):1352-1355
A 16-y-old boy who had undergone bone marrow transplantation for relapsed acute lymphoblastic leukaemia developed liver cirrhosis and refractory ascites, which did not respond to salt restriction, diuretics and abdominal paracentesis. Liver transplantation was not feasible because of poor nutritional status, pre-existing renal dysfunction and uncertainty about the prognosis of his leukaemia. The patient underwent a successful transjugular intrahepatic portosystemic shunt (TIPS), with immediate resolution of ascites, enabling cessation of diuretics and improvement in nutritional status. At 24 mo following TIPS there has been no re-accumulation of ascites. CONCLUSION: TIPS may have a role in the management of refractory ascites secondary to liver cirrhosis in selected children. 相似文献
93.
94.
Cor P van der Hart Michel PJ van den Bekerom Thomas W Patt 《Journal of orthopaedic surgery and research》2008,3(1):24
Objective
The objective of this study was to evaluate the incidence of radiographic osteoarthritis in the operated knee in comparison with the contralateral knee ten years after a bone-tendon bone patellar autograft ACL-reconstruction and to evaluate to which level patients regain activity ten years after reconstruction. 相似文献95.
In a 5-year period, 92 patients with biliary obstruction proximal to the pancreatic segment were evaluated with computed tomography (CT). Seventy-three were judged to have technically optimal studies. Observations of the level of obstruction were compared with data from 50 percutaneous transhepatic cholangiograms; CT data enabled the level of obstruction to be correctly predicted in 46. CT enabled correct prediction of the distribution of obstructing lesions in all 18 patients with intrahepatic obstruction. Forty-four of the 73 patients had pathologic examination of the porta hepatitis. CT findings of obstructing mass and lesser omental nodes resulted in correct prediction of malignancy in 25 (92%) of 27 patients; the absence of such findings enabled correct prediction of benign disease in 13 (77%) of 17 individuals. CT is most valuable as a noninvasive means of planning surgical or radiologic drainage procedures in patients with biliary obstruction. 相似文献
96.
HL Zaaijer ; H Vrielink ; PJ van Exel-Oehlers; HT Cuypers ; PN Lelie 《Transfusion》1994,34(7):603-607
BACKGROUND: Recently, new immunoblot assays for the detection of antibodies to hepatitis C virus (HCV) became available. STUDY DESIGN AND METHODS: The performance of five confirmatory anti-HCV immunoblot assays was studied with samples with known HCV antibody and HCV RNA status. The assays were a third-generation strip recombinant immunoblot assay (RIBA-3, Chiron Corp., Emeryville, CA), a second-generation HCV blot (DB-2 blot, Diagnostic Biotechnology, Singapore), the Wellcozyme HCV Western blot (Murex blot, Murex Diagnostics, Dartford, UK), an immunodot HCV assay (Matrix, Abbott Laboratories, Chicago, IL), and the third-generation HCV line immunoassay (Liatek-III, Organon Teknika, Boxtel, The Netherlands). RESULTS: Sensitivity on samples from 48 HCV RNA-positive, second-generation RIBA (RIBA-2)-positive persons and specificity on samples from 31 low-risk donors was 96 percent or better for all assays. The sensitivity on 31 HCV RNA-positive, RIBA-2- indeterminate samples was as follows: Liatek-III, 94 percent; RIBA-3, 90 percent; Murex blot, 61 percent; Matrix, 55 percent; and DB-2 blot, 39 percent. In testing 39 HCV RNA-negative, RIBA-2-indeterminate donor samples, the percentage found to be negative was Liatek-III, 77 percent; RIBA-3, 67 percent; Murex blot, 49 percent; DB-2 blot, 33 percent; and Matrix, 15 percent. The order of sensitivity on four HCV seroconversion series was (from high to low): RIBA-3, Liatek-III, DB-2 blot, Murex blot, and Matrix; the differences were small. CONCLUSION: Detection of HCV antibodies was not refined by the addition of new HCV antigens (NS5, E2/NS1), but by improved classical antigens (core, NS3, NS4). Replacement of the commonly used RIBA-2 will resolve the status of a high proportion of RIBA-2-indeterminate samples. 相似文献
97.
The provision of renal replacement therapy for adults in England and Wales: recent trends and future directions 总被引:1,自引:7,他引:1
Roderick PJ; Ferris G; Feest TG 《QJM : monthly journal of the Association of Physicians》1998,91(8):581-587
We assessed the level of provision of renal replacement therapy for adults
in England and Wales. All autonomous main renal units in England (n = 52)
and Wales (n = 5) were surveyed in 1996. Data for England were compared to
the 1993 National Renal Review. The acceptance rate in England 1995 was 82
(80-85) per million population (p.m.p.) compared with 67 (65-70) p.m.p. in
1991-2. The rate in 1995 in Wales was 109 (98- 122) p.m.p. The prevalence
rate in England was 476 p.m.p. at end-1995 compared to 393 p.m.p. in 1993,
in Wales it was 487 p.m.p. The number of main renal units in England did
not rise between 1993 and 1995; capacity was increased by use of more
treatment shifts and temporary haemodialysis stations, and by opening more
satellite units. The main growth was in hospital haemodialysis. There was
an uneven geographical distribution of services. Patients accepted were
older with more comorbidity. The use of better-quality processes of
dialysis increased. The steady-state position for RRT will not be reached
for over a decade. Health authorities will face continued pressure to fund
increases in quantity and quality improvements. A stronger evidence base of
the effectiveness of therapies, and a national registry to monitor the
equity and cost-effectiveness of services are needed.
相似文献
98.
Coagulation parameters of CPD fresh-frozen plasma and CPD cryoprecipitate-poor plasma after storage at 4 degrees C for 28 days 总被引:1,自引:0,他引:1
A pilot study was performed on the storage of plasma and cryosupernatant plasma at 4 degrees C for up to 28 days. Eight bags, four of CPD fresh-frozen plasma (FFP) and four of CPD cryosupernatant plasma (CSP, plasma without cryoprecipitate), were sampled during storage for assays of pH; factors V, VIII, IX, and XI; fibrinogen; prothrombin time; activated partial thromboplastin time (APTT); plasma protein electrophoresis; viscosity; and C1q binding. No changes were found in viscosity or the plasma protein electrophoretic pattern, and there was no detectable immune complex formation. The fibrinogen concentration remained constant, and the prothrombin time showed a gradual increase of 2.5 seconds for both groups of plasma. The labile coagulation factor V decreased gradually for FFP and CSP to 58 and 64 percent of its initial value, respectively (51 +/− 8% and 54 +/− 6% of the value of fresh pooled plasma). Factor VIII decreased to 36 percent of its initial value in FFP (48 +/− 14% of fresh pooled plasma). In CSP, factor VIII decreased after 28 days to 7 percent of its initial value (7 +/− 1% of fresh pooled plasma). The APTT increased for FFP from 28 to 35.8 +/− 1.1 seconds and for CSP from 36 to 49.5 +/− 4.9 seconds. The only chemical change observed for both plasmas was a rise in pH, from 7.27 to 7.56, after 28 days. The results of this pilot study indicate that FFP can be stored at 4 degrees C for 28 days with sufficient recovery of coagulation factors to maintain hemostasis.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
99.
100.