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Records at the USAF School of Aerospace Medicine, Hyperbaric Medicine Division, were reviewed to determine whether a relationship exists between the length of time from development of symptoms of altitude chamber decompression sickness (DCS) to start of compression therapy and the outcome of treatment. During the 5-year period from 1 January 1984 to 31 December 1988, 233 cases of altitude chamber DCS were treated in USAF hyperbaric chambers. Information obtained from each record included age, sex, time from exposure to symptom onset, time from symptom onset to start of compression therapy, time required for resolution of symptoms, and number of treatment failures (failure to resolve during the first treatment dive or recurrence of symptoms after the first dive). Analysis of the data obtained from treatment records reveals a direct relationship between length of delay to treatment with compression therapy and outcome of treatment. Patients successfully treated with a single treatment dive had an average delay to treatment of 10.6 h. Patients that failed treatment after one dive (failed to resolve or recurred) had an average delay to treatment of 18.2 h. The difference between these groups is significant (p less than 0.05). Outcome of treatment was not significantly related to patient age, sex, or type of symptoms. A discussion of factors causing delays in treatment of decompression sickness is included.  相似文献   
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High-resolution MR imaging with local coils   总被引:4,自引:0,他引:4  
Kneeland  JB; Hyde  JS 《Radiology》1989,171(1):1-7
We propose the following rules to govern the choice of local coils by the practicing radiologist: 1. Smaller coils permit smaller FOVs and better resolution. The coil should be as small as possible. 2. Match the ROS of the coil to the FOV, which will be determined by the anatomic region of interest. 3. For the case of a choice between surface coils or between a surface and a whole- or partial-volume coil, the anatomic region should lie on the high side of the crossover point. For the case of a choice among whole-volume coils, the smallest coil that surrounds the region of interest should be chosen. 4. Considerations in regard to the anatomic shape or the need to vary the position of the structure may alter the choice of coil from that obtained by S/N considerations alone.  相似文献   
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自国产沉香(Aquilaria sinensis)[瑞香科(Thymeleaceae)植物]的挥发油中,经硅胶柱层析和离心薄层层析分离得到一新的倍半萜,命名为异白木香醇(isobaimuxinol),根据光谱(IR,~1HNMR,~(13)CNMR,2 D-NMR和MS)分析确定其结构式为(Ⅰ)所示,并用X-光衍射晶体解析进一步确定了其立体化学。同时,也从该植物挥发油的低沸点部分分离得到四个已知化合物:苄基丙酮,对甲氧基苄基丙酮,茴香酸和β-沉香呋喃。这些化合物均为首次从该植物中得到。  相似文献   
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We describe two type 2 diabetic patients with unilateral emphysematous pyelonephritis who responded to medical treatment alone. Escherichia coli was isolated in both patients. The presence of gas was confirmed early by ultrasound and CT scan of abdomen. Following treatment, good functional recovery was demonstrable in the affected kidneys by isotope renogram. We stress the need for early diagnosis of this condition and aggressive treatment with broad spectrum antibiotics.  相似文献   
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BACKGROUND: Polyethylene glycol (PEG) has been shown to potentiate antigen-antibody reactions. STUDY DESIGN AND METHODS: To investigate the utility of PEG in pretransfusion testing, a blinded comparison study of PEG and a low-ionic-strength additive solution (LISS) was conducted. A total of 500 patient samples were tested in parallel with reagent antibody-detection cells using blind-coded PEG and LISS potentiators. RESULTS: In 34 (34%) of 100 samples with known antibodies in the Rh, Kell, Duffy, Kidd, and MNS systems, PEG antiglobulin reactions were stronger (total score, 382) than LISS antiglobulin reactions (total score, 216), and in 66 cases (66%), they were equal to those of LISS. Of 400 samples without detectable antibodies, 384 were negative with PEG and LISS, and 16 were positive in PEG tests and negative in LISS. Seven of the 16 were clinically important antibodies (D, 1; E, 3; Fya, 1; Jka; 1; Jkb, 1), and four were clinically benign antibodies (Le(a), 2; McCc, 1; Sda, 1). Five of the 16 demonstrated inconclusive PEG reactions, for a false-positive rate of 5 in 400 (1.3%). Of the 500 samples, none was negative in PEG tests and positive in LISS (0% false-negative rate). CONCLUSION: Although PEG demonstrates a relatively high false-positive rate, PEG is more sensitive than LISS in detecting clinically significant antibodies.  相似文献   
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目的:观察大黄苷元联合溶栓治疗对大鼠脑缺血损伤肺胃组织的保护作用。方法:实验于2005-08/2006-07在河南中医学院老年医学研究所实验室完成。①260只SD大鼠采用随机数字法分为假手术组20只、模型组60只、尿激酶组60只、大黄苷元组60只、大黄苷元 尿激酶组60只;除假手术组外,其余各组根据缺血后动脉用药时间又各分为3,6,9h3个时间点,每个时间点20只。②自体血栓结合线栓阻塞大鼠大脑中动脉制备局灶性脑缺血动物模型。③各组大鼠均于术前4d灌胃用药,大黄苷元组、大黄苷元 尿激酶组用大黄苷元灌胃(灌胃体积为每100g大鼠1mL),假手术组、模型组和尿激酶组用等体积的生理盐水灌胃;动脉用药除假手术组外,其余各组分别于造模后3,6,9h经导管由区域动脉给药,尿激酶组与大黄苷元 尿激酶组用尿激酶(用药体积为20μL),模型组和大黄苷元组区域动脉用同等体积的生理盐水。④动脉给药后24h,观察大鼠脑组织病理损伤、颅内和胃出血率、脑和肺组织含水量、肺和胃病理损伤变化。结果:实验过程中因麻醉、操作等原因死亡及剔除大鼠156只,进入结果分析104只。①颅内和胃出血率:尿激酶组9h大鼠颅内出血率较模型组高(66.67%,28.57%,P<0.05);尿激酶组9h脑和胃出血率较3h高(脑:66.67%,18.75%;胃:41.18%,17.65,P<0.05);大黄苷元 尿激酶组9h颅内出血率较尿激酶组9h低(P<0.05)。②脑和肺及胃组织病理改变:各模型组大鼠脑、胃和肺组织病理损伤均较假手术组明显;各用药组脑和肺组织分别较相应时间模型组减轻;各组脑、胃和肺组织损伤9h均较其3h明显;大黄苷元 尿激酶组9h较相应时间点尿激酶组和大黄苷元组损伤减轻(P<0.05)。③脑和肺组织含水量:各模型组脑和肺组织含水量均较假手术组增高(P<0.01);尿激酶组和大黄苷元 尿激酶组各时间点均较模型组降低(P<0.01);各组9h分别较其3h脑和肺含水量增加(P<0.01,P<0.05);大黄苷元 尿激酶组6h脑组织和9h肺含水量分别较尿激酶组降低(P<0.05)。结论:脑缺血后延迟溶栓治疗可引起大鼠脑和胃出血率增高、脑组织和肺组织水肿加重,脑和肺及胃组织病理损伤明显;大黄苷元联合溶栓可降低脑出血率,改善神经细胞超微结构,降低脑和肺组织含水量,对脑缺血肺和胃组织损伤具有保护作用。  相似文献   
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