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11.
茶色素对冠心病及高血压病病人血小板功能的影响 总被引:1,自引:0,他引:1
目的:探索茶色素对冠心病、高血压病病人血小板功能的影响。方法:冠心病病人36例(男性21例,女性15例;年龄64±s4a);高血压病病人30例(男性18例,女性12例;年龄58±8a)。采用茶色素250mg,po,tid,30d为一个疗程。结果:治疗后TXB2下降,6-keto-PGP1α上升,TXB2/6-keto-PGF1α比值下降(P<0.01或P<0.05),GMP-140下降(P<0.05),PagT,PadT下降(P<0.05)。结论:茶色素具有降低血小板表面活性作用,抑制血小板聚集和粘附,抗血栓形成,改善微循环,对冠心病和高血压病病人起到积极的防治作用。 相似文献
12.
Guthrie and Buchwald (1991) proposed an ad hoc procedure for assessing the statistical significance of waveform difference potentials that may arise in a variety of psychophysiology research contexts. In our paper, an alternative method is presented and demonstrated that has fewer underlying assumptions than does the Guthrie-Buchwald test and may, therefore, produce better results in some situations. In particular, the test proposed here (a) is distribution free, (b) requires no assumption of an underlying correlation structure (e.g., first-order autoregressive), (c) requires no estimate of the population autocorrelation coefficient, (d) is exact, (e) produces p values for any number of subjects and time points, and (f) is highly intuitive as well as theoretically justifiable. This procedure may be used to carry out multiple comparisons with exact specification or experimentwise error, however, this test is based on permutation principles and may require large amounts of computer time for its implementation. 相似文献
13.
Diagnosis and treatment of thoracic outlet syndrome 总被引:2,自引:0,他引:2
Masataka Abe Tadashi Shimamura Jun Nishida Katsuaki Ichinohe 《Journal of orthopaedic science》1997,2(2):119-127
Patients who develop symptoms of thoracic outlet syndrome (TOS) have a predisposing anatomic abnormality. In most patients
with TOS, the symptoms are caused by entrapment of the brachial plexus and they do not arise from compression of the subclavian
artery, as was previously thought. The tests advocated for diagnosing this common syndrome (i.e., evaluating the positional
compression of the artery when the arms are raised, the neck is turned, or the shoulders are braced) cannot accurately diagnose
this syndrome. There are two reasons for this. The symptoms of TOS are not related to the compression of the artery in the
outlet in 98% of patients, and 75% of normal individuals without symptoms show diminished radial pulse on various provocation
tests. We employed four timed provocation tests (minute tests) to diagnose TOS: the timed Morley test, timed Wright test,
timed Eden test, and elevated arm stress exercise, all of which are very sensitive. In normal individuals without symptoms,
20% experience transitional symptoms such as slight pain and tiredness, on these tests indicating a subclinical state. TOS
is treated by keeping the thoracic outlet wide, this being done either conservatively or surgically. In 1993 and 1994, we
conservatively treated 418 of 422 patients with TOS by means of active exercise, a brace, and by block therapy. These measures
did not reduce the symptoms in 23 of these patients, so surgical treatment was indicated. In the remaining 4 of the 422 patients,
conservative treatment was not indicated and surgery was performed directly. All the patients showed significant clinical
improvement of varying degree.
Presented at the 69th Annual Meeting of the Japanese Orthopaedic Association, Tokyo, April 12, 1996 相似文献
14.
15.
测定72例健康老年人(60-84岁)和65例健康青中年人(20-50岁)血清和尿β2微球蛋白(β2m),发现前血清β2m浓度比后明显增高(p<0.001);老年组≥70岁尿液β2m浓度也明显增高(p<0.05)。结果表明肾小球滤过率下降随年龄增长而降低,以后再出现肾小管功能减退。本试验较血清尿素氮、肌酐和内生肌酐清除率测定更为敏感。 相似文献
16.
分析了GELOGIQ 400B超机不能启动的故障,经对电源、主板、硬盘的维修,机器恢复正常。 相似文献
17.
本文应用XD—Ⅰ型微电脑程序刺激器检查26例患者,在窦房结功能检查中测定了窦房结恢复时间、窦房传导时间及固有心率;在房室传导功能的估计中测定了文氏点,2∶1阻滞点及房室结的有效不应期;在室上性心动过速中测定了旁路不应期,房室结双通道,折返区及折返性心动过速区;还进行了心脏负荷试验及右束支不应期等方面的测定。并就其方法,判断标准及临床意义等分别作了讨论。 相似文献
18.
Margaret Sullivan Pepe Ziding Feng Gary Longton Joseph Koopmeiners 《Statistics in medicine》2009,28(5):762-779
Development of a disease screening biomarker involves several phases. In phase 2 its sensitivity and specificity is compared with established thresholds for minimally acceptable performance. Since we anticipate that most candidate markers will not prove to be useful and availability of specimens and funding is limited, early termination of a study is appropriate, if accumulating data indicate that the marker is inadequate. Yet, for markers that complete phase 2, we seek estimates of sensitivity and specificity to proceed with the design of subsequent phase 3 studies. We suggest early stopping criteria and estimation procedures that adjust for bias caused by the early termination option. An important aspect of our approach is to focus on properties of estimates conditional on reaching full study enrollment. We propose the conditional‐UMVUE and contrast it with other estimates, including naïve estimators, the well‐studied unconditional‐UMVUE and the mean and median Whitehead‐adjusted estimators. The conditional‐UMVUE appears to be a very good choice. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
19.
J. Heidrich P. U. Heuschmann P. Kolominsky-Rabas A. G. Rudd C. D. A. Wolfe 《European journal of neurology》2007,14(3):255-261
Valid classification of stroke is essential to initiate effective acute management and early secondary prevention strategies. To accurately evaluate stroke subtype a number of diagnostic procedures have to be performed. This study sought to investigate variations in use of diagnostic procedures across selected European hospitals. First-ever stroke patients were sampled over a 1-year period through 11 hospital-based registers across 10 European countries. We defined a diagnostic standard for valid aetiological classification of ischemic stroke including brain imaging, vascular imaging and echocardiography. The impact of socio-demographic, clinical and structural characteristics on performance of the diagnostic standard was assessed using multivariate logistic regression analyses. A total of 1721 patients were included in the study. 83.1% received brain imaging, ranging from 32.8% to 100%. The diagnostic standard was performed in 40.4% of stroke patients, ranging from 0% to 77.2%. Patients with increasing age ( P < 0.001) and with more severe strokes ( P = 0.001) were less probably to receive the diagnostic standard. Patients treated in stroke units and neurological departments were more frequently investigated with the diagnostic standard ( P < 0.001). Less than half of hospitalized stroke patients across Europe underwent diagnostic procedures to allow for aetiological classification of stroke, which may hamper the initiation of effective early management and secondary prevention. 相似文献
20.
D. M. Jensen P. Damm B. Sørensen L. Mølsted-Pedersen J. G. Westergaard L. Korsholm P. Ovesen H. Beck-Nielsen 《Diabetic medicine》2003,20(1):51-57
AIMS: To study if established diagnostic threshold values for gestational diabetes based on a 75-g, 2-h oral glucose tolerance test can be supported by maternal and perinatal outcomes. METHODS: Historical cohort study of 3260 pregnant women examined for gestational diabetes on the basis of risk indicators. Information on oral glucose tolerance test results and clinical outcomes were collected from medical records. RESULTS: There was an increased risk of delivering a macrosomic infant in women with 2-h capillary blood glucose of 7.8-8.9 mmol/l compared with women with 2-h glucose < 7.8 mmol/l. Despite treatment, 2-h glucose of 9.0-11.0 mmol/l and > or = 11.1 mmol/l were both associated with increased rates of macrosomia, spontaneous preterm delivery, hypertensive complications, and neonatal hypoglycaemia. Adverse outcomes tended to be more frequent in women with 2-h glucose > or = 11.1 mmol/l than in women with 2-h glucose of 9.0-11.0 mmol/l. CONCLUSIONS: The risk for several maternal and perinatal complications increased with the diagnostic threshold for 2-h glucose. Large-scale blinded studies are needed to clarify the question of a clinically meaningful diagnosis of gestational diabetes mellitus. Until these results are available, a 2-h threshold level of 9.0 mmol/l after a 75-g oral glucose tolerance test seems acceptable. 相似文献