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51.
Percutaneous cholecystography was performed on 13 children who had biliary system abnormalities: two had biliary hypoplasia, five had sclerosing cholangitis, three had cirrhosis, two had distal choledochal obstruction, and one had an obstructed portoenterostomy. In 12 patients transcholecystic cholangiography showed, without significant complications, the intra-and extrahepatic bile ducts. In one patient with primary sclerosing cholangitis, the intrahepatic bile ducts were not opacified satisfactorily; dilatation of the gallbladder required surgical drainage. The transcholecystic technique is indicated when the intrahepatic bile ducts are either mildly dilated or not dilated. 相似文献
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54.
6-Fluorocatecholamines as false adrenergic neurotransmitters 总被引:2,自引:0,他引:2
C C Chiueh Z Zukowska-Grojec K L Kirk I J Kopin 《The Journal of pharmacology and experimental therapeutics》1983,225(3):529-533
In the present study 6-fluoronorepinephrine (6F-NE) is shown to be formed from 6-fluorodopamine (6F-DA) in vivo. The beta-hydroxylated fluorocompound is taken up by and stored in the adrenergic nerve terminals and can be released during sympathetic nerve stimulation. In the heart, the turnover rate of the exogenously administered 6F-NE was about the same as that of tritium-labeled norepinephrine. In the central nervous system, 6F-DA can be taken up by the nigrostriatal neurons. After depolarization of the dopaminergic neurons by potassium, 6F-DA is released along with the endogenous dopamine. Systemic administration of 6F-NE to the pithed rats produces dose-dependent increases in blood pressure but does not increase the heart rate. The vasopressor potency of 6F-NE is about the same as that of l-norepinephrine, about 2-fold greater than that of dl-norepinephrine. Combined treatment with yohimbine and prazosin antagonizes completely the vasopressor effect of 6F-NE. The duration of the pressor response to 6F-NE was twice that of dl- or l-norepinephrine. The present study indicates that 6-fluorocatecholamines fulfill the criteria for adrenergic false transmitters and may be useful in positron emission tomographic scanning for mapping specifically the adrenergic nervous system in the brain or in the peripheral sympathetic nerves. 相似文献
55.
Kee F; McDonald P; Kirwan JR; Patterson CC; Love AH 《QJM : monthly journal of the Association of Physicians》1997,90(11):669-676
To determine the factors that influenced doctors' prioritization and
decisions on safe waiting time for coronary artery bypass surgery, 50
'paper patients', based on a random sample of cases who actually had
surgery, were assessed by 33 clinicians. We used linear regression models
to reflect the impact of clinical and non-clinical 'cues' on safe waiting
time and priority decisions. The benefits of surgery tended to be
over-estimated. For example, the average perceived gain in life expectancy
for patients with left main-stem disease was 6.74 years. However, models
incorporating only the perceptions of benefit as independent variables
(i.e. the anticipated symptom reduction, MI risk reduction and life
expectancy extension), had only modest explanatory power (mean R2 was 0.55
for safe waiting time, and 0.56 for priority decisions). Models which
incorporated perceptions of benefit and the cases' clinical and
non-clinical characteristics had generally much higher explanatory power
(mean R2, 0.83 and 0.86, respectively). Lifestyle and demographic variables
had much less impact on the doctors' judgements than the major clinical
cues of angina severity and left main-stem stenosis. Demographic and
lifestyle cues had different impacts on safe waiting time and priority for
about 25% of doctors.
相似文献
56.
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
57.
BACKGROUND: Transfusion-associated graft-versus-host disease can be prevented by gamma radiation of blood components. The increased use of blood components donated for patients by their family members has resulted in an increased demand for the storage and handling of irradiated units, and the ability to freeze the cells would allow storage beyond their current expiration date. STUDY DESIGN AND METHODS: To assess the effect of freezing and deglycerolization on irradiated red cells, studies of autologous radiolabeled red cell recovery were performed using normal volunteers. Each unit of CPDA-1 red cells was immediately divided into two equal volumes. Further handling of each half was identical except that one was irradiated (3500 cGy). The units were grouped under three protocols: I, irradiated on Day 0 and frozen on Day 5 (n = 4); II, irradiated on Day 7, rejuvenated, and frozen on Day 14 (n = 5); and III, irradiated on Day 14, rejuvenated, and frozen on Day 18 (n = 3). All cells were frozen for 3 to 10 months at -80 degrees C. RESULTS: Irradiated and control units showed no significant differences in supernatant potassium or hemoglobin. Autologous 24-hour posttransfusion recoveries (mean +/− SD) for the three groups were: I, 89.7 +/− 5.6 percent (control, 90.6 +/− 3.2%); II, 85.3 +/− 5.7 percent (control, 83.7 +/− 3.0%); and III, 79.5 +/− 1.4 percent (control, 82.6 +/− 5.2%). CONCLUSION: Irradiated red cells can be frozen after being stored under various conditions and can still meet established guidelines requiring 75-percent recovery 24 hours after transfusion. 相似文献
58.
Kee F; McDonald P; Kirwan JR; Patterson CC; Love G 《QJM : monthly journal of the Association of Physicians》1997,90(2):117-123
In a clinical judgement analysis, we used linear regression models to
reflect the impact of clinical and non-clinical cues on priority decisions,
by comparing the stated prioritization policies of 30 clinicians with their
actual policies as revealed by an appraisal of 50 'paper patients'.
Correspondence was modest for some cues, e.g. 25 doctors said they
accounted for age, but age only had a significant bearing in the derived
decision models of two doctors. Correspondence between the derived and
expressed weights was greatest for clinical angina grade and the presence
of left main stem stenosis. Correlation between the rank order of
importance between the two models was poor for most of the cues, and
statistically significant only for smoking. However, stated policies made
it appear that lifestyle factors such as smoking habit would influence
prioritization decisions for most clinicians but policies derived from
actual prioritization decisions seldom related to lifestyle or demographic
variables. There were significant differences in the degree of correlation
between the two models according to the experience of the clinician.
However, correspondence was not significantly better for doctors with
cardiological training than those without. The overall contribution of
demographic and lifestyle factors to decision making appears to be small,
suggesting that they should be omitted from prioritization guidelines.
相似文献
59.
Yeh KM Chiueh TS Siu LK Lin JC Chan PK Peng MY Wan HL Chen JH Hu BS Perng CL Lu JJ Chang FY 《The Journal of antimicrobial chemotherapy》2005,56(5):919-922
OBJECTIVES: To describe the immunological responses and clinical outcome of coronavirus (SARS) infected healthcare workers (HCW) who had been administered with convalescent plasma as a treatment. METHODS: Convalescent plasma (500 mL) was obtained from each of three SARS patients and transfused into the three infected HCW. Donors were blood type O and seronegative for hepatitis B and C, HIV, syphilis and human T-cell lymphotropic virus types I and II (HTLV-I and -II). Serum antibody (IgG) titre was >640. Apharesis was performed with a CS 3000 plus cell separator followed by the forming of the convalescent phase plasma. As part of the routine check with donated plasma, the convalescent plasma was confirmed free of residual SARS-CoV by RT-PCR. Serial serum samples obtained from the recipients of the convalescent plasma were collected to undertake real-time quantitative RT-PCR for SARS-CoV for direct measurement of viral concentration. Specific immunoglobulin IgM and IgG concentrations were titrated using an antigen microarray developed in-house. RESULTS: Viral load dropped from 495 x 10(3), 76 x 10(3) or 650 x 10(3) copies/mL to zero or 1 copy/mL one day after transfusion. Anti-SARS-CoV IgM and IgG also increased in a time-dependent manner following transfusion. All three patients survived. One HCW became pregnant subsequently, delivering 13 months after discharge. Positive anti-SARS-CoV IgG was detected in the newborn. Passive transfer of anti-SARS-CoV antibody from the mother was considered as a possibility. CONCLUSIONS: All infected HCW whose condition had progressed severely and who had failed to respond to the available treatment, survived after transfusion with convalescent plasma. 相似文献
60.
M Weinstock A P Zavadil A J Rosin C C Chiueh I J Kopin 《The Journal of pharmacology and experimental therapeutics》1978,206(1):91-96
Oxotremorine, 0.25 mg/kg, produces marked tremor in the rat, which is abolished by scopolamine, 0.5 mg/kg, and is substantially reduced in intensity and duration both by adrenalmedullectomy and by chemical sympathectomy with 6-hydroxydopamine. Oxotremorine increases plasma norepinephrine from 0.62 +/- 0.07 to 3.01 +/- 0.47 ng/ml and plasma epinephrine, from 0.82 +/- 0.14 to 3.42 +/- 0.48 ng/ml, in conscious unrestrained rats. l-Propranolol (0.5-2.5 mg/kg) reduces tremor, and at 2.5 mg/kg is more effective than either chemical sympathectomy or adrenal demedullation. d-Propranolol and sotalol are also active at 4 and 10 times the dose of l-propranolol, respectively. l-Propranolol does not prevent the rise in catecholamines induced by oxotremorine. It is suggested that stimulation of central muscarinic receptors causes tremor by a combination of two effects. There is an increase in cholinergic influence to motor efferents accompanied by an activation of the sympathoadrenal system to release catecholamines which augment tremor by stimulation of beta2 adrenoceptors. 相似文献