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81.
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
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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
84.
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
85.
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
86.
87.
88.
89.
Thrombosis in inflammatory bowel disease: clinical setting, procoagulant profile and factor V Leiden 总被引:7,自引:0,他引:7
Jackson LM; O'Gorman PJ; O'Connell J; Cronin CC; Cotter KP; Shanahan F 《QJM : monthly journal of the Association of Physicians》1997,90(3):183-188
Patients with inflammatory bowel disease have an increased frequency of
thromboembolism, and microvascular thrombosis has been proposed as a
contributory pathogenic factor. The mechanism of enhanced procoagulant
activity is not understood. We examined the clinical setting of
thromboembolic events in 52 patients with Crohn's disease or ulcerative
colitis, and assessed the procoagulant laboratory profile, including Factor
V Leiden, in a subset of 20 patients to identify procoagulant risk factors.
Patients who developed thrombosis tended to be young; 60% of thrombotic
events occurred in patients under 50 years. Multiple thromboembolic
episodes occurred in 13% and unusual sites of thrombosis (e.g.
intracardiac, cerebral, inominate veins) in 11%. No risk factor was
identifiable in 52% of cases and two-thirds of thromboses occurred in an
out-patient setting. The mortality rate was 8%. Evidence for inflammatory
disease activity was found in only 45% of patients with ulcerative colitis
at the time of the thromboembolic event, in contrast to 89% of those with
Crohn's disease. Assays for specific coagulation defects were negative in
all cases tested (protein S, C were normal in 17/17; anti-thrombin III,
anti-phospholipid antibodies and activated protein C resistance were
negative in 20/20, and only 1/20 patients was found to be heterozygous for
Factor V leiden. Thrombosis in inflammatory bowel disease is important
because it occurs in a young population, often in unusual sites, and has a
high mortality. The development of thrombosis is related to active
inflammatory disease in most patients with Crohn's disease but apparently
not in those with ulcerative colitis. Since approximately half of the
patients had no other identifiable risk factor, there remains a substantial
group of patients with IBD who develop thrombosis for unknown reasons.
相似文献
90.