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81.
Ultraviolet-B (UV-B) irradiation of platelet concentrates (PCs) may prevent the development of posttransfusion HLA alloimmunization. This study evaluated the effect of increasing doses of UV-B radiation on stored PCs. Pooled PCs were irradiated at UV-B doses of 600, 2400 or 10,000 mJ per cm2 and stored up to 96 hours under standard blood bank conditions. Compared to nonirradiated room-temperature and 37 degrees C controls, the irradiated units showed no significant changes in platelet count, white cell count, discharge of lactate dehydrogenase, release of beta-thromboglobulin, metabolism of ATP, ADP, ammonia, glutamine, glutamate, hypoxanthine, pCO2, or pO2 at any time of storage following any of the three UV-B doses. However, after a dose of 10,000 mJ per cm2, there were significant decreases in in vitro assays of platelet function-specifically, osmotic recovery and morphology score. Some metabolic systems were also affected by the 10,000 mJ per cm2 radiation dose, as shown by a decline in pH and bicarbonate and an increase in glucose consumption and lactate production (p < 0.05). The changes in these latter assays appeared only after 96 hours of postirradiation storage. Such changes were not seen in either the room- temperature or 37 degrees C control groups. Thus, heat generated during irradiation, per se, did not appear responsible for the observed in vitro changes in platelet function and metabolism. On the basis of the assays analyzed, it is concluded that UV-B irradiation of PCs at doses up to 10,000 mJ per cm2 does not induce significant metabolic or functional derangements following short-term storage (24-48 hours).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
82.
LD Petz ; L Calhoun ; P Yam ; M Cecka ; G Schiller ; AR Faitlowicz ; R Herron ; D Sayah ; RB Wallace ; A Belldegrun 《Transfusion》1993,33(9):742-750
A patient without evident immune deficiency who received a transfusion of blood from a second-degree family member developed fatal transfusion- associated graft-versus-host disease (TA-GVHD). The donor was homozygous for an HLA haplotype for which the recipient was heterozygous (one-way HLA match). All 39 reported cases of TA-GVHD in immunocompetent patients were reviewed to ascertain the predisposing factors and to define the indications for irradiating blood for this population. HLA typing was described in 15 cases; in 13, including seven related and six unrelated donors, a one-way HLA match was present. Thirty-one (79%) of the 39 cases were reported from Japan (and 196 other cases are cited in the Japanese literature), but a one-way HLA match among unrelated donors at HLA-A, -B, -DR loci is only approximately two to four times more likely in Japanese persons than in whites. Fresh blood (< 96 hours old) was used in 29 (94%) of the 31 cases reported from Japan and in 33 (87%) of 38 cases overall (in one case, the age of the blood used was not reported). Thus, factors that appear to predispose to TA-GVHD in immunocompetent patients are a one- way HLA match, fresh blood, and, possibly, Japanese ancestry. Irradiating cellular blood components from all blood relatives of transfusion recipients will not completely eliminate the risk of TA- GVHD. 相似文献
83.
低氧训练对下丘脑-垂体-肾上腺皮质轴内分泌相关激素的影响 总被引:1,自引:0,他引:1
目的:总结低氧训练对下丘脑-垂体-肾上腺皮质轴内分泌相关激素的影响,为科学运动训练提供依据。资料来源:应用计算机检索中国期刊全文数据库1994-01/2006-10的相关文章,检索词"低氧,低氧训练,下丘脑-垂体-肾上腺,激素",并限定文章语言种类为中文。并应用计算机检索美国国立医学图书馆NCBI1980-01/2006-10的相关文章,检索词"Hypoxic Training,organism endocrine system,hormone",并限定文章语言种类为English。资料选择:对资料进行初审,选取低氧训练与下丘脑-垂体-肾上腺分泌的相关激素有关的文献,并作初步分类,同类文献首选近年发表的核心期刊文章。排除重复及综述类文献。资料提炼:共收集到95篇相关文章,其中56篇属于重复及综述类文献,对符合标准38篇文献进行分析整理。资料综合:①高海拔状态下机体对低氧产生应激反应,表现为下丘脑-垂体-肾上腺皮质轴的适应性运转,血中促肾上腺皮质激素浓度增加,以调节机体对应激刺激的适应能力,同时使促肾上腺皮质激素释放因子分泌增加。②高原训练后,睾酮和皮质醇的变化都较明显,其总体变化均趋于降低,睾酮/皮质醇值有升有降,从一定意义上反映了机体的机能状况与疲劳积累程度。③低氧还引起大鼠血浆β-内啡肽浓度升高,可使心房钠尿素增加、前列腺素增加、血管内皮素分泌增加及抑制血管内皮舒张因子的分泌。结论:激素对机体的新陈代谢、生长发育、各种功能活动以及维持内环境稳态等方面发挥重要的调节作用,低氧训练对机体激素的影响一直应该受到人们的关注。 相似文献
84.
Nicole H. Raney Evan J. Petersen Tracy A. Smith James E. Cowan Daniel G. Rendeiro Gail D. Deyle John D. Childs 《European spine journal》2009,18(3):382-391
The objective of the study was to develop a clinical prediction rule (CPR) to identify patients with neck pain likely to improve
with cervical traction. The study design included prospective cohort of patients with neck pain referred to physical therapy.
Development of a CPR will assist clinicians in classifying patients with neck pain likely to benefit from cervical traction.
Eighty patients with neck pain received a standardized examination and then completed six sessions of intermittent cervical
traction and cervical strengthening exercises twice weekly for 3 weeks. Patient outcome was classified at the end of treatment,
based on perceived recovery according to the global rating of change. Patients who achieved a change ≥+6 (“A great deal better”
or “A very great deal better”) were classified as having a successful outcome. Univariate analyses (t tests and chi-square) were conducted on historical and physical examination items to determine potential predictors of successful
outcome. Variables with a significance level of P ≤ 0.15 were retained as potential prediction variables. Sensitivity, specificity and positive and negative likelihood ratios
(LRs) were then calculated for all variables with a significant relationship with the reference criterion of successful outcome.
Potential predictor variables were entered into a step-wise logistic regression model to determine the most accurate set of
clinical examination items for prediction of treatment success. Sixty-eight patients (38 female) were included in data analysis
of which 30 had a successful outcome. A CPR with five variables was identified: (1) patient reported peripheralization with
lower cervical spine (C4–7) mobility testing; (2) positive shoulder abduction test; (3) age ≥55; (4) positive upper limb tension
test A; and (5) positive neck distraction test. Having at least three out of five predictors present resulted in a +LR equal
to 4.81 (95% CI = 2.17–11.4), increasing the likelihood of success with cervical traction from 44 to 79.2%. If at least four
out of five variables were present, the +LR was equal to 23.1 (2.5–227.9), increasing the post-test probability of having
improvement with cervical traction to 94.8%. This preliminary CPR provides the ability to a priori identify patients with
neck pain likely to experience a dramatic response with cervical traction and exercise. Before the rule can be implemented
in routine clinical practice, future studies are necessary to validate the rule. The CPR developed in this study may improve
clinical decision-making by assisting clinicians in identifying patients with neck pain likely to benefit from cervical traction
and exercise.
This study was approved by the Institutional Review Board at Brooke Army Medical Center, Fort Sam Houston, Texas. The opinions
and assertions contained herein are the private views of the authors and are not to be construed as official as reflecting
the views of the Department of the Army, Department of the Air Force, Department of the Navy, or the Department of Defense. 相似文献
85.
Jung Nathalie Namjoshi Sarika Mohammed Yousuf Grice Jeffrey E. Benson Heather A. E. Raney Sam G. Roberts Michael S. Windbergs Maike 《Pharmaceutical research》2022,39(5):935-948
Pharmaceutical Research - The quality testing and approval procedure for most pharmaceutical products is a streamlined process with standardized procedures for the determination of critical quality... 相似文献
86.
Abstract Background: One of the unique variables for successful implantation of transcatheter aortic valves involves the ability to secure an access route for deployment of the aortic valve. Aim of study: A large number of the high‐risk patients with critical aortic stenosis referred for transcatheter valve implantation approach may not be candidates for the femoral approach due to peripheral vascular disease with the morbidity and mortality increased severalfold in patients who develop access related complications. Method & Results: A thorough knowledge and review of various alternate access site techniques and trouble shooting are therefore important and required by the implanting cardiac surgeons involved in transcatheter aortic valve therapy. Conclusion: The article review highlights the various percutaneous, hybrid, and surgical access techniques platforms available as well as options for implantation of these devices . (J Card Surg 2010;25:373‐380) 相似文献
87.
A R Rajakumar K Prasad S V Mantha M Khouri B Raney 《The Canadian journal of cardiology》1999,15(9):989-998
BACKGROUND: Oxygen free radicals (OFRs) have been implicated in ischemic-reperfusion cardiac injury. Use of percutaneous transluminal coronary angioplasty (PTCA) has created renewed interest in salvation of ischemic myocardium. The PTCA procedure is similar to the ischemia-reperfusion model. It is possible that OFRs are increased following PTCA. However, OFR-related cardiac complications are uncommon and the evidence for lipid peroxidation is conflicting. PATIENTS AND METHODS: In this study the levels of plasma malondialdehyde, OFR-producing activity of polymorphonuclear leukocytes (PMNL-CL) and blood antioxidant enzymes (superoxide dismutase, catalase and glutathione peroxidase) were measured in peripheral venous blood of 50 consecutive patients with stable angina undergoing elective PTCA. The ability of Isovue (used during PTCA) and of streptokinase (used during thrombolysis) to scavenge OH in the high performance liquid chromatography method and to reduce OH-induced lipid peroxidation were also assessed. Patients were divided into three groups: group 1, single vessel PTCA; group 2, two or more vessel PTCA; and group 3, combined single and multivessel PTCA. RESULTS: The results indicated that there was an increase in PMNL-CL (22% to 44%) and a decrease in plasma malondialdehyde (33% to 40%) at 60 mins following PTCA. The activity of antioxidant enzymes remained unaltered. Isovue scavenged OH in a concentration-dependent manner and was complete at a concentration below that used in patients. Streptokinase, on the other hand, was ineffective in scavenging OH. CONCLUSIONS: These results suggest that, in spite of increased production of OFR by polymorphonuclear leukocytes and unaltered activity of antioxidant enzymes, lipid peroxidation decreased. Lack of lipid peroxidation may have been due to the OH-scavenging property of Isovue. The observed differences in OFR-related complications between PTCA and thrombolytic therapy may have been due to the antioxidant activity of Isovue. 相似文献
88.
89.
90.
Dachman AH; Lieberman J; Osnis RB; Chen SY; Hoffmann KR; Chen CT; Newmark GM; McGill J 《Radiology》1997,203(2):427