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281.
282.
目的:评价肝移植术后患者血清总胆汁酸水平、胆酸/鹅脱氧胆酸比值在肝移植术后发生排斥反应及肝功能延迟恢复时的变化规律。方法:选择2004-01/2004-12在大连医科大学器官移植中心进行肝移植手术的患者28例,同时收集大连医科大学附属二院门诊健康体检者和肝硬化患者血清学标本各12例作为对照,所有观察对象均知情同意。采用高效液相色谱检测肝移植术后患者血清中不同种类胆汁酸及总胆汁酸水平,也与常规肝功能监测指标谷草转氨酶和总胆红素加以比较,对肝移植术后患者血清指标与肝功能恢复之间的关系进行综合评价。结果:所有观察对象均进入结果分析,无脱落。①肝硬化组、肝移植组术前患者的血清总胆汁酸水平显著高于正常对照组(P<0.05)。②肝移植患者术后发生排斥反应或肝功能延迟恢复时,血清总胆汁酸水平较术前明显升高(P<0.05),胆酸/鹅脱氧胆酸比值明显降低(P<0.05),且比谷草转氨酶、总胆红素的变化提前发生,随着供肝功能的恢复它们将逐渐恢复正常。结论:总胆汁酸及胆酸/鹅脱氧胆酸比率可以作为肝移植术后发生排斥反应及肝功能延迟恢复的早期诊断指标,其对于肝移植术后急性排斥反应的早期诊断、早期治疗有重大意义。  相似文献   
283.
BACKGROUND: The use of antithrombotic agents and falls are independently associated with an increased risk of hemorrhagic injury. However, few studies have delineated the risk of fall-related hemorrhagic complications in persons who are taking antithrombotic therapy. The objective of this study was to compare the rates of fall-related hemorrhagic injury in hospital in-patients who are taking and not taking antithrombotic therapy. METHODS: A 4-year retrospective chart review of consecutive patients who fell during admission to a 500-bed tertiary-care teaching hospital was conducted. Major hemorrhagic injuries including subdural hematomas and major bleeding/cuts, patients' use of antithrombotic medication (warfarin, aspirin, clopidogrel and heparin) and their anticoagulation status at the time of their fall were recorded. RESULTS: A total of 2635 falls in 1861 patients were reviewed. Approximately 10% of falls caused major hemorrhagic injury. One fall resulted in a subdural hematoma. Persons taking warfarin were less likely to suffer a fall-related major hemorrhagic injury compared with persons not taking antithrombotic therapy (warfarin, 6%; no therapy, 11%; p = 0.01). Logistic regression showed that fall-related major hemorrhagic injury was associated with female gender (odds ratio 1.6; 95% CI 1.3, 2.1), use of aspirin (odds ratio 1.4; 95% CI 1.1, 1.8) and use of clopidogrel (odds ratio 2.2; 95% CI 1.1, 4.8), but not with the use of warfarin or heparin, or the intensity of anticoagulation. CONCLUSIONS: In this study, compared with persons taking no antithrombotic therapy, those taking warfarin had lower rates of fall-related hemorrhagic injuries. The absolute rate of the development of fall-related intracranial hemorrhagic injury such as subdural hematomas was low, even in persons taking warfarin. These counter-intuitive results may be due to selection bias, and suggest that physicians are very conservative in selecting patients for warfarin therapy, choosing only those who are sufficiently healthy to be at much lower than average risk of suffering fall-related hemorrhagic injuries. This phenomenon may lead to physicians overestimating the potential for fall-related major hemorrhagic injury in persons taking antithrombotic therapy, with the possible denial of warfarin therapy to many of those who would benefit. This perception may contribute to the care gap between the number of patients who would theoretically derive overall benefit from warfarin therapy and those who are actually receiving it.  相似文献   
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285.
目的:分析肿瘤坏死因子基因多态性分布与中国西南地区汉族人群鼻咽癌易感性的关系。方法:选择2000-10/2005-09在华西医科大学第一附属医院就诊的100例鼻咽癌患者为鼻咽癌组,均经过病理科活检确诊,其中包括未治疗44例,放疗后37例,放疗加化疗后19例,选择100名同期入院健康体检者为对照组。所有受试对象为中国西南地区汉族人,均对检测项目知情同意。采用聚合酶链反应-限制性片段长度多态性的方法检测100例中国西南地区汉族鼻咽癌患者和100名健康对照者肿瘤坏死因子α基因启动子区-308位点及肿瘤坏死因子β基因第一内含子252位点的等位基因以及基因型频率,分析两位点多态性与鼻咽癌遗传易感性的关系。结果:鼻咽癌组患者肿瘤坏死因子β( 252)位点G/A杂合子基因型频率显著高于对照组(57%,29%,P<0.01),野生型(G/G基因型)频率低于健康对照组(23%,51%,P<0.01),等位基因A的频率高于健康对照组(48.5%,13%,P<0.01);肿瘤坏死因子α(-308)位点基因型以及等位基因频率与对照组相比较无统计学差异。结论:本实验人群中未发现肿瘤坏死因子α(-308)位点多态性与鼻咽癌易感性无关;肿瘤坏死因子β( 252)位点基因多态性与鼻咽癌具有相关性,A等位基因可能是鼻咽癌的遗传易感基因,G/A杂合子基因型个体较易患鼻咽癌。  相似文献   
286.
SUMMARY Neurological dysfunction from base of skull metastasis of prostate cancer is rare. In this case, dysphagia was the presenting symptom and relief occurred after orchidectomy. Improvement of neurological symptoms usually occurs only after local radiotherapy.  相似文献   
287.
T-B-NK+ severe combined immunodeficiency (SCID) is caused by a defect in V(D)J recombination. A subset of these patients has a mutation in one of the non-homologous end joining (NHEJ) genes, most frequently the Artemis gene. Artemis is involved in opening of hairpin-sealed coding ends. The low levels of residual DH-JH junctions that could be amplified from patients' bone marrow precursor B cells showed high numbers of palindromic (P)-nucleotides. In 25% of junctions, microhomology was observed in the P-nucleotide regions, whereas this phenomenon was never observed in junctions amplified from bone marrow precursor B cells from healthy controls. We utilized this difference between Artemis-deficient cells and normal controls to develop a V(D)J recombination assay to determine hairpin-opening activity. Mutational analysis of the Artemis gene confirmed and extended the mapping of an N-terminal nuclease active site, which contains several indispensable aspartate residues. C-terminal deletion mutants did not show such severe defects in the V(D)J recombination assay using transient overexpression of (mutated) Artemis protein. However, a C-terminal deletion mutation causes T-B-NK+ SCID, indicating that the Artemis C terminus is essential for V(D)J recombination at the normal Artemis expression level. The V(D)J recombination assays used in this study contribute to the diagnostic strategy for T-B-NK+ SCID patients.  相似文献   
288.
Ninety-nine patients with acute nonlymphocytic leukemia (ANLL) received HLA-identical bone marrow transplants (BMTs) from sibling donors after preparation with high doses of busulfan and cyclophosphamide. Forty- nine patients were transplanted in first complete remission (CR), and 50 patients were transplanted in second and third CR and early relapse. Fifty-three received one of three regimens containing primarily low- dose cyclophosphamide (group I) for graft-v-host disease (GVHD) prophylaxis; since March 1983, 46 patients received intravenous (IV) cyclosporine (group II). After December 1983, only cytomegalovirus (CMV)-seronegative blood products were used in appropriate patients, and since April 1984 patients seropositive for herpes-simplex virus (HSV) and CMV received high-dose acyclovir prophylaxis. For patients transplanted in first CR, there was a significantly lower incidence of acute GVHD (P = .005) and deaths related to GVHD and interstitial pneumonitis (P = .001) in patients in group II. This was reflected in an improved Kaplan-Meier probability of disease-free survival (DFS) in the 22 patients transplanted in group II as compared with the 27 patients in group I (64% +/- 10% v 30% +/- 9%, P = .017). The probability of remaining in remission was slightly lower in group II (82% +/- 9% v 94% +/- 6%, P = .479). For patients transplanted in second and third CR and early relapse, the incidence of acute GVHD (P = .026) and deaths related to GVHD and interstitial pneumonitis was significantly lower in group II (P = .029); the probability of remaining in remission was also less (47% +/- 15% v 91% +/- 15%, P = .022). However, the probability of DFS was not significantly different between the two groups (26% +/- 10% v 35% +/- 18%, P = .957). We conclude that transplantation for patients in first CR who received IV cyclosporine therapy is effective treatment; patients with more refractory disease treated with the same cyclosporine regimen (group II) had a lower incidence of GVHD than those treated in group I, but survival did not improve because of an increase in the number of relapses and other nonleukemic complications.  相似文献   
289.
OBJECTIVE: To investigate the sympathetic and parasympathetic cardiovascular function in primary Sj?gren's syndrome (SS) and to investigate the possible relation with ocular dryness. METHODS: 41 (40 women) patients with primary SS, mean age 50 years (range 20-80) with a mean disease duration of eight years (range 1-30), were studied. In each patient direct arterial blood pressure (BP), heart rate (HR) and respiration were measured continuously for two hours. The function of the autonomic circulatory regulation was evaluated by measuring the heart rate response to deep breathing (6 cycles/min) and by means of the Valsalva manoeuvre and the responses of BP, HR and plasma noradrenaline (norepinephrine) concentrations to a 10 minute 60 degree head up tilt test. Pupillography was done to evaluate ocular autonomic function. RESULTS: The HR-Valsalva ratio was abnormal in 24% of the patients, and the HR variability during forced respiration was abnormal in 56% of the patients. The HR responses to both the Valsalva manoeuvre and deep breathing, as indicators of parasympathetic function, were abnormally low in 6 of 41 (15%) patients. In only two patients the decrease in systolic BP in response to the head up tilt test, as indicator of sympathetic function, was more than 20 mm Hg. However, increment of plasma noradrenaline concentration during head up tilt test and the overshoot of BP in phase IV of the Valsalva manoeuvre, as indicators of sympathetic function, were normal in both patients. Thus, no evidence for sympathetic dysfunction was found, whereas evidence for parasympathetic failure occurred sometimes. Autonomic pupillary function in patients with primary SS and healthy controls, as well as the Schirmer test in patients with or without evidence for parasympathetic dysfunction as based on the results of the Valsalva and deep breathing tests, were not significantly different. CONCLUSION: Parasympathetic, but not sympathetic dysfunction seems to occur in a subgroup of primary SS. Results show that this does not necessarily contribute to the typical ocular dryness in this condition.  相似文献   
290.
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