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51.
52.
目的探讨医源性脾脏损伤脾切除对结直肠癌切除患者术后长期生存的影响。方法对1990年1月1日至1999年12月31日10年间行结直肠癌手术切除并附带脾切除患者进行病例配对回顾研究。分析患者年龄、性别、依据美国麻醉学医师协会(ASA)标准评估的身体状况、疾病分期、手术类型及预后等资料。配对病例来自同一医疗中心,性别、年龄、疾病分期及手术类型完全相同。手术附带脾切除患者为试验组,未切脾者为对照组。结果55例患者行医源性脾切除术,对照组在年龄、性别、身体状况、疾病分期及手术类型上与之匹配。随访时间(从手术开始到患者死亡或者最后一次随访1为2~205个月(中位随访时间为43个月)。Cox比例危险度模型进行Kaplan-Meier法生存分析发现两组间差异有显著性意义,不切除脾脏对患者生存有利(危险度1.8,95%可信区间为1-3.3,P=0.0399),未切脾组与切脾组5年生存率分别为70%和47%,10年生存率分别为55%和38%。结论结直肠癌患者在行结肠或直肠切除时,因医源性脾脏损伤而切除脾脏者,预后较差。  相似文献   
53.
对人流感病毒A/Udorn/72(H_3N_2)株与禽类流感病毒A/Mallard/NY/78/(H_2N_2)重组后的重组株分析表明,仅含禽类病毒的核蛋白(NP)或膜蛋白(M)的RNA片段的重组株,在松鼠猴的呼吸道繁殖是受限制的。另外。仅有禽类的RNAl和NS基因的重组株(Clone 12)在松鼠猴的气管内的繁殖也明显受限制,而只具有其中一个基因的Clone 9, Clone 2, 则限制就不明显。由此表明,禽类流感病毒的NP和M基因在宿主范围的繁殖限制中起主要作用,而RNAI和SN基因的结合,同样起着繁殖受限制作用。  相似文献   
54.
Mode of regulation of natural killer cell activity by interferon   总被引:18,自引:5,他引:18       下载免费PDF全文
Whereas xenogeneic tumors such as baby hamster kidney or HeLa cells grow in nude mice, the same cells persistently infected with a variety of viruses are rejected. Spleen cells from normal nude mice were found to be induced to produce interferon and to exert natural killer (NK) activity on virus persistently infected (PI) tumor cells, and not on uninfected parental cells in vitro. The phenotype of the interferon-producing cells and the NK effector cells was found to be the same namely, Qa 5(+), Ly 5(+), ganglio-N- tetraosylceramide, with 35 percent of the NK cells also expressing Thy 1.2. NK activity against virus PI tumor cell lines could be nonspecifically augmented both in vivo and in vitro by prior contact with virus PI tumor cells. It was unambiguously demonstrated with chemically homogeneous mouse interferon that interferon, and not a contaminant, was responsible for the augmentation of NK activity in vitro. Studies on the mode of interferon action in augmenting NK activity revealed that the target cell for interferon action was serologically distinct from the NK effector cell. Anti-Ly 5 + complement (C)-treated spleen cells were depleted of NK activity and the ability to produce interferon, but, upon incubation with interferon for 1-3 h, regained both NK activity and susceptibility to anti-Ly 5 + C. Treatment with anti-Qa 5 + C eliminated NK activity, which could not be restored by the addition of interferon. We conclude that interferon produced by Ly 5(+) cells in response to virus PI tumor cells acts on Ly 5(-) precursor cells and induces their differentiation into functional Ly 5(+) NK effector cells.  相似文献   
55.
Spinal anaesthesia for elective caesarean section is associated with maternal hypotension, secondary to alteration of sympathetic tone and hypovolemia, in up to 70% of cases. Measurement of the subaortic variation in the velocity time integral (VTI) after passive leg raising allows prediction of fluid responsiveness. Our objective, in this prospective single‐centre observational study, was to assess the ability of change in VTI after 45° passive leg raising to predict hypotension after spinal anaesthesia. Ultrasound measurements were performed just before elective caesarean section. Anaesthesia, intravenous coloading and prophylactic vasopressor treatment were standardised according to current guidelines. We studied 40 women. Hypotension occurred in 17 (45%) women. The area (95%CI) under the receiver operating characteristics (ROC) curve for the prediction of spinal hypotension was 0.8 (0.6–0.9; p = 0.0001). Seventeen women had a change in VTI with leg elevation ≤ 8%, which was predictive for not developing hypotension, and 11 had a change ≥ 21%, predictive for hypotension. The grey zone between 8% and 21%, with inconclusive values, included 12 women. We suggest that cardiac ultrasound provides characterisation of the risk of hypotension following spinal anaesthesia at elective caesarean section, and therefore may allow individualised strategies for prevention and management.  相似文献   
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Indinavir plasma levels are associated with antiretroviral efficacy; however, little data are available regarding toxicity. We assessed the relationship between indinavir pharmacokinetic (PK) characteristics and severe nephrolithiasis as well as other severe or serious adverse reactions. Patients included in the ANRS CO8 APROCO-COPILOTE cohort and receiving 800 mg indinavir three times daily as a first-line protease inhibitor were eligible for this study. To be included in the analysis, their plasma sample at month 1 (M1) had to be available (n = 282) to estimate using population PK modeling, indinavir PK characteristics, ie, maximum (Cmax) and trough plasma (Cres) concentrations, area under the curve (AUC), and observed/predicted concentration ratio (CR). A Cox model was used to estimate the independent effect of Cmax, Cres, AUC, and CR on the hazard of severe nephrolithiasis and serious adverse reactions. At M1, median Cmax was 6205 ng/mL, Cres 631 ng/mL, AUC 24,242 ng . h/mL, and CR 0.6. After a median follow up of 12 months, 11% of patients (30 of 282) had experienced at least one serious adverse reaction among which 12 were nephrolithiasis. In the multivariate analyses, early high indinavir Cres (ie, >/=1000 ng/mL at M1) was associated with a higher rate of severe nephrolithiasis (hazard ratio = 6.7; 95% confidence interval = 1.8-25.2; P < 0.01) and was also associated with a higher rate of all serious adverse reactions but only when nephrolithiasis were included among those cases. Prospective and early indinavir Cres determination should be recommended in the patient's care management and dosage adjustments.  相似文献   
58.
A nontoxigenic strain isolated from a fatal human case of bacterial sepsis was identified as a Clostridium strain from Clostridium botulinum group III, based on the phenotypic characters and 16S rRNA gene sequence, and was found to be related to the mosaic C. botulinum D/C strain according to a multilocus sequence analysis of 5 housekeeping genes.  相似文献   
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60.
The impact of nosocomial tuberculosis remains poorly known. There is a real risk that is relatively higher when the probability of community acquisition declines. Diagnosis is difficult due to the natural history of tuberculosis infection so that most cases of nosocomial contamination result in infection without disease expression. The nosocomial origin is rarely recognized. Though diagnosis is difficult, prevention is well described: early diagnosis of tuberculosis disease and treatment as well as respiratory isolation in case of suspected tuberculous bacilli. Particular care is required in units managing immunodepressed patients where the risk of contamination and development of overt tuberculosis is greater.  相似文献   
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