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排序方式: 共有487条查询结果,搜索用时 15 毫秒
1.
Immunoglobulin E (IgE) was measured in the sera of 18 healthy adult volunteer donors, 67 adults with various types of solid neoplasms, and 17 adults with clinical allergy by means of a double-antibody radioimmunoassay. There was no siginificant difference in the geometric mean serum IgE level between all cancer subjects and the healthy control subjects except that cancer and noncancer patients who had definite clinical allergies showed an increased mean IgE level. Similarly, there was no significant difference in the mean IgE level of any of the six cancer subgroups studied when compared to the control mean. Thus, there was no evidence reflected in serum levels that IgE plays a role in the immunopathology of the cancer population tested. 相似文献
2.
Selective and nonselective shunts for variceal bleeding. A prospective study of 103 patients 总被引:4,自引:0,他引:4
R W Busuttil 《American journal of surgery》1984,148(1):27-35
Based on the experience reported herein, the following conclusions have been made: (1) Although nonoperative means, including sclerotherapy, have an important role in the management of bleeding varices, they are not definitive means of treating recurrent variceal hemorrhage. (2) Because of the maintenance of hepatopetal flow and splanchnic venous hypertension, a selective shunt is associated with a lower incidence of encephalopathy and provides a better quality of life than does a nonselective shunt. Thus, an elective distal splenorenal shunt is the elective operation of choice for recurrent variceal hemorrhage. (3) Nonselective shunts can be performed with similar expectation of patient survival as selective shunts, but because of increased encephalopathy, should be reserved for emergency operations, in cases of unsuitable venous anatomy, and in those patients with intractable ascites. (4) A well-conceived elective shunt procedure can be performed with low operative mortality and long-term patency, results in significant survival, and is still considered the "gold standard" for treatment of variceal bleeding. 相似文献
3.
目的探讨锁定钢板治疗肱骨近端骨折的临床疗效及并发症发生情况。方法 200例肱骨近端骨折患者平均随机分为锁定钢板组和传统手术组,分别予锁定钢板固定和传统手术固定,术后随访6~12个月,比较两组的疗效和并发症发生情况。结果锁定钢板组疗效优秀率(80%)高于传统手术组(24%),(χ2=6.44,P〈0.05),总体治疗效果优于传统手术组(H=8.43,P〈0.05)。随访期间两组出现的并发症包括愈合不良、内固定不良、肱骨头坏死等,锁定钢板组并发症发生率均低于传统手术组,总并发症发生率锁定钢板组也低于传统手术组(P〈0.05)。结论锁定钢板治疗肱骨近端骨折的临床疗效确切,并发症少,有进一步研究推广的价值。 相似文献
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6.
This study is an attempt to unify the evaluation of patients with well-differentiated thyroid cancer after ablative therapy. As such, serum thyroglobulin determinations on and off thyroid hormone (T4) therapy and iodine 131 total body scans were examined in 53 patient studies. No metastases were found in patients whose thyroglobulin value was undetectable (< 1 ng/ml). Values during T4 therapy that were detectable, even as low as 4.2 ng/ml, were occasionally associated with metastases. After T4 withdrawal, thyroglobulin value and scan were obtained. Neither metastasis nor clinically detectable cancer was found in patients whose thyroglobulin value was less than 10 ng/ml while off T4. Conversely, a value greater than 10 ng/ml was often associated with documented metastases even when the scan was negative. In summary, a thyroglobulin value less than 1 ng/ml during T4 therapy or less than 10 ng/ml off T4 therapy suggests successful therapy and a routine scan could be avoided unless clinically indicated. However, a value greater than 10 ng/ml suggests the presence of metastasis despite a negative scan. Thyroglobulin determination substantially improves the management of these patients. 相似文献
7.
Electrical and contractile consequences of Na+ or Ca2+ gradient reduction in cultured heart cells 总被引:2,自引:0,他引:2
J M Burt 《Journal of molecular and cellular cardiology》1982,14(2):99-110
The normal electrical and contractile activity of cultured neonatal rat ventricular cells is characterized and compared to activity seen in low [Ca2+]0 and low [Na+]0 solutions. In 0 Ca2+/0.5 mm EGTA solutions electrical activity is altered: the maximum diastolic potential (m.d.p.), maximum rate of rise (), and overshoot (o.s.) are reduced, while duration is increased. Low [Ca2+]0 activity is insensitive to TTX and blocked by La3+. In low [Na+]0 solutions electrical activity is generally absent; when present and o.s. are decreased while duration is increased. Low [Na+]0 activity is blocked by La3+. These data suggest the presence of one La3+-sensitive slow inward current channel. The absence of spontaneous electrical activity in low [Na+]0 solutions suggests an inhibition of automaticity. To determine if this inhibition is due to a reduction of the Na+ gradient, drugs which raise [Na+]i were examined. Both monensin (a Na+ ionophore) and ouabain inhibit the occurrence of spontaneous action potentials (cells respond to stimulation) indicating a dependence of pacemaker activity on a normal Na+ gradient. During Na+ gradient reduction, asynchronous subcellular contractile activity occurs independent of membrane potential fluctuation. This asynchronous activity is inhibited by La3+ or when Ca2+0 is absent, but continues in the presence of verapamil (normal activity is blocked by all three conditions). The Na+Ca2+ exchange system is unaffected by verapamil but blocked by La3+, while both these drugs block the slow inward current. These data indicate that the Na+Ca2+ exchange system can directly supply Ca2+ (independent of electrical activity at the membrane) to intracellular sites that support contractile activity. 相似文献
8.
Rex N. MacAlpin 《American heart journal》1980,99(5):555-564
The lead distribution of ST segment elevation produced by severe “spasm” of major coronary arteries was correlated with the specific artery involved in a group of 110 cases of variant angina with single vessel coronary arterial spasm made up from eight cases personally observed and 102 cases abstracted from published literature.The most sensitive and specific lead for ST elevation during anterior descending (LAD) coronary arterial spasm was V3; V2 was almost as good. For spasm of either the right (RCA) or circumflex coronary artery (CMFX), Leads 3 and aVF showed ST elevation most frequently; electrocardiographically it was difficult to distinguish between spasm of these two vessels. ST elevation in Leads V5 and V6 was not specific, occurring in some cases of spasm of each of the three major coronary arteries. ST elevation in Lead V1 occurred in either RCA or LAD spas, but never in CMFX spasm. ST elevation in Lead 1 was never seen with isolated RCA spasm.No single lead can detect all cases of transient ST elevation. Simultaneous monitoring of Leads 3 and V3 would have detected 98.2% of 333 cases of ST elevation reviewed, and addition of Lead aVL would have detected most of the remainder. These findings should be considered in lead selection for monitoring to detect ST elevation, and in using the ECG to identify spastic coronary arteries. 相似文献
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10.
David J. Skorton John S. Child Joseph K. Perloff 《The American journal of medicine》1980,69(3):377-382
Anterior mitral leaflet diastolic flutter and flutter of contiguous cardiac structures are accepted M-mode echocardiographic signs of aortic regurgitation. Ninety-four subjects (47 normal and 47 with aortic regurgitation on angiography) had echocardiograms evaluated (double-blind) by two observers for the presence of anterior mitral leaflet diastolic flutter or ventricular septal diastolic flutter. For the entire study population, sensitivity was 66 percent for anterior mitral leaflet diastolic flutter, 36 percent for ventricular septal diastolic flutter and 72 percent for diastolic flutter over-all (i.e., present on either or both). Severe chronic aortic regurgitation always revealed anterior mitral leaflet diastolic flutter. Mild to moderate aortic regurgitation without mitral stenosis had an 81 percent sensitivity for over-all diastolic flutter; with mitral stenosis, over-all sensitivity of diastolic flutter was 44 percent. Specificity of anterior mitral leaflet diastolic flutter was 83 percent, of ventricular septal diastolic flutter 98 percent, of diastolic flutter over-all 83 percent. There was no observer discordance over diastolic flutter in severe aortic regurgitation, but 19 percent discordance over diastolic flutter in mild to moderate aortic regurgitation without mitral stenosis, and 31 percent discordance in mild to moderate aortic regurgitation with mitral stenosis. There was 26 percent disagreement over the absence of diastolic flutter in normal subjects, predominantly regarding anterior mitral leaflet diastolic flutter. Predictive value of diastolic flutter was 81 percent when present and 75 percent when absent. We conclude the following: (1) In severe aortic regurgitation, interobserver agreement is good for anterior mitral leaflet diastolic flutter, which is a highly sensitive sign; (2) interobserver agreement is good for ventricular septal diastolic flutter, which is highly specific but insensitive; (3) disagreement was greatest over anterior mitral leaflet diastolic flutter in normal subjects; and, (4) with coexisting mitral stenosis, diastolic flutter is not a sensitive sign. 相似文献