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41.
T-cell receptor alpha-chain cDNA were generated from unstimulated peripheral blood mononuclear cells of a DR2,3,52a individual using a modified anchor PCR method. Fifty-six cDNA clones were identified representing 47 distinct T-cell receptor clonotypes and 26 VA loci. This analysis identified a new VA gene family VA30, and a new member of the VA6 gene family.  相似文献   
42.
Background: We performed a phase I study of a novel system of complete hepatic venous isolation and extracorporeal chemofiltration in patients with unresectable hepatocellular carcinoma (HCC) to determine (a) whether systemic exposure to doxorubicin could be limited after high-dose hepatic arterial infusion (HAI), and (b) the hepatic maximum tolerated dose (MTD) of doxorubicin. Methods: Ten patients with biopsy-proven HCC were treated with 20-min HAI of doxorubicin (17 total treatments). Two patients were treated with doxorubicin 60 mg/m2, three patients were treated at 90 mg/m2, and five patients received 120 mg/m2. A newly developed dual-balloon vena cava catheter was advanced from the femoral vein, and the balloons were inflated to isolate and capture total hepatic venous outflow. The hepatic venous blood was pumped through extracorporeal carbon chemofilters before return of the blood to the systemic circulation. Results: Peak systemic doxorubicin levels were an average 85.6% lower than were peak prefilter levels (p<0.01). Because all catheters were placed percutaneously and because the chemofiltration markedly limited systemic chemotherapy exposure, patients were discharged 1 day after 16 of the 17 treatments. The hepatic and systemic MTD of doxorubicin in this treatment protocol was 120 mg/m2. Conclusions: This novel system of complete hepatic venous isolation and chemofiltration limits systemic chemotherapy toxicity and will allow use of higher doses of chemotherapeutic agents to treat HCC. The results of this study were presented at the 46th Annual Cancer Symposium of The Society of Surgical Oncology, Los Angeles, California, March 18–21, 1993.  相似文献   
43.
44.
The presence of noble gas and other short-lived radionuclides in air borne effluents from RBMK-1500-type reactor has been investigated using experimental and theoretical instrumentation for detection purposes. Activity concentrations of (85m)Kr, (87)Kr, (88)Kr, (135m)Xe, (135)Xe, (133)Xe and (41)Ar were measured in air emissions from Ignalina NPP using a special method and special equipment. Theoretical detection of reactor-borne radionuclides and investigation of their behaviour in a nuclear fuel during operation of nuclear reactor was performed using an analytical model based on reactor physics. An innovative method for the estimation of noble gas flow time from the defective nuclear fuel element through the ventilation stack of NPP to the atmosphere based on comparison of the experimentally and theoretically evaluated activity ratios of (88)Kr/(85m)Kr; (135)Xe/(133)Xe has been proposed. The estimated flow time of noble gas provides an excellent possibility to obtain modelling-based information about the qualitative and quantitative content of atmospheric releases from NPP.  相似文献   
45.
46.
We present an adenoid cystic carcinoma of the base of tongue in a 48-year-old male with a restricted chromosomal alteration by cytogenetic and spectral karyotypic analysis (SKY). SKY and G-banding analyses identified the t(6;14)(q25;q13) as the sole structural aberration in all metaphases analyzed. This finding supports a critical role for this event in the development of this tumor. The implications of chromosome 6q translocation in this case and in previously reported adenoid cystic carcinomas are highlighted and discussed.  相似文献   
47.

Objective

Participation in evidenced‐based arthritis self‐management programs (SMPs) has not been well documented. The purpose of this study was to investigate the participation rate and participant characteristics in a closed cohort of subjects in a geographic region where arthritis SMPs have been offered multiple times and continuously for 2 decades.

Methods

Data were from osteoarthritis (OA) and rheumatoid arthritis subjects participating in the Arthritis, Rheumatism, and Aging Medical Information System (ARAMIS) who resided in the San Francisco (SF) Bay area who had responded to questions about ever participating in an SMP. Differences between participants and nonparticipants were examined by t‐tests and chi‐square tests.

Results

Questions added to the Health Assessment Questionnaire were returned by 1,176 patients; 618 resided in the SF Bay area. Of the SF Bay area sample, 41.9% had participated in an SMP. Small group SMPs, which had been offered multiple times, in diverse settings, continuously over the past 2 decades, were attended by the highest proportion (28%) of participants. Characteristics of participants and nonparticipants in the SF Bay area were similar (~70 years old, 15 years of education, and the majority had OA [~72%]). However, a higher proportion of participants were white (88% versus 82%; P = 0.046) and female (82% versus 73%; P < 0.05).

Conclusion

When arthritis SMPs were offered multiple times in diverse settings and continuously over many years, >40% of the cohort was reached. More research is needed with larger samples and different geographic regions to identify participation rates in more diverse populations.  相似文献   
48.
We have identified a leukocyte activation syndrome that is occasionally associated with the transfusion of intraoperatively recovered erythrocytes. This syndrome appears to result from intravascular damage caused by leukocytes activated during the erythrocyte salvage process. We hypothesize that this syndrome is part of a larger disease grouping: disseminated intravascular inflammation (DII). DII is the analog of the coagulation disorder disseminated intravascular coagulation. In disseminated intravascular coagulation, the organ damage results from uncontrolled activation of the clotting pathway; in DII the damage is caused by leukocytes that have become activated by direct contact with bacteria or in rare instances--such as erythrocyte salvage--in the absence of bacteria and bacterial products. Recent studies of the hazards associated with intraoperative blood salvage indicate that activation of leukocytes can be achieved by exposure to activated platelets alone. If such activated leukocytes are reinfused along with the washed erythrocytes, widespread organ damage may result. The lung is the organ most severely affected by activated leukocytes. Adult respiratory distress syndrome is one outcome. It is likely that DII is a presently unrecognized pathophysiological process that complicates a variety of primary disease states and increases their lethality.  相似文献   
49.
OBJECTIVE: The purpose of this study was to compare the preparation costs of two common methods used for neonatal red blood cell transfusion aliquots. METHODS: Three months of data from a Level 2 and Level 3 neonatal intensive care unit (NICU) were used to determine the comparative cost for red cell aliquot transfusions using an eight bag aliquot/transfer system or the syringe set system. Using leuko-poor red blood cell blood collected in Adsol and containing approximately 320 ml of red blood cells and supernatant solution, the average cost of neonatal transfusion aliquots was determined using the Charter Medical syringe set and the Charter Medical eight bag aliquot/transfer system. RESULTS: A total of 126 red blood cell transfusion aliquots were used over the three month period. The amount transfused with each aliquot ranged from 5.0 ml - 55.0 ml with an average of 24.0 ml per aliquot. The cost per aliquot using the eight aliquot/transfer set was calculated as $36.25 and the cost per aliquot using the syringe set cost was calculated as $30.71. Additional benefits observed with the syringe set included decreased blood waste. CONCLUSION: When comparing Charter Medical multiple aliquot bag sets and the Charter Medical syringe aliquot system to provide neonatal transfusions, the use of the syringe system decreased blood waste and proved more cost effective.  相似文献   
50.
Binding of [3H]Ro 5-4864 to mitochondrial membrane preparations of rat cerebral cortex was measured after repeated (5 days) IV administration of diazepam (10 mg/kg daily) and clonazepam (2.5 mg/kg daily). The B(max) value for [3H]Ro 5-4864 was significantly reduced in rats treated with diazepam (-49%) but not in those treated with clonazepam. These findings suggest the involvement of peripheral-type binding sites in the development of rapid tolerance to the sedative effects of benzodiazepines. A downregulation of [3H]Ro 5-4864 (-65%) was also observed after repeated administration of Ro 5-4864 (4 mg/kg daily), thus confirming that this compound behaves as an agonist at its own recognition sites.  相似文献   
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