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1.
儿童心脏移植是治疗年龄18岁终末期心力衰竭患者的有效手段。1967年美国Adrian Katrowitz实施第一例儿童心脏移植,近五年全球80家单位每年开展500例左右。中国儿童心脏移植起步晚、发展慢。自1995年开展第一例儿童心脏移植以来,目前国内已登记病例超过130例。中华医学会器官移植学分会组织心脏移植专家,总结国内外相关研究最新进展,结合国际指南和临床实践,针对儿童心脏移植受者选择及常用术式的操作要点、程序和方法,以及各类复杂先天性心脏病心脏移植的特殊操作,制订《中国儿童心脏移植适操作规范(2019版)》。  相似文献   
2.
The relationship between stroke and physical disability was examined in a cohort of adult, Framingham, Massachusetts, residents who, between 1948 and 1951, were assembled for a longitudinal examination of cardiovascular disease. Multivariate analyses examined the amount of residual disability attributable to stroke among 2540 community-dwelling survivors, 27 years after their initial examination, after controlling for age, cardiovascular risk factors, other cardiovascular diseases, and eight general health conditions related to physical disability. Among men living in the community, a history of stroke explained 12% of the variance in physical disability. Suffering a stroke, however, was not as strongly related to physical disability among women living in the community, accounting for only 3% of the variance. Results suggest that although older men and women die from the same major causes, they may not be disabled by the same conditions.  相似文献   
3.
目的 观察培养液在 pH值为 6 .8、7.3、7.6条件下rIL - 2、IFN -α2b、ADM及合用维拉帕米对人肝癌细胞 74 0 4杀伤作用的影响。方法 MTT法于 96孔培养板上进行杀伤实验 ,测定培养液pH值分别为 6 .8、7.3、7.6状态下 ,rIL - 2、IFN -α2b、ADM、及与维拉帕米联合杀伤人肝癌细胞 70 4 0的差异。结果 pH值为 7.6状态下rIL - 2、IFN -α2b、ADM及合用维拉帕米杀伤效果最佳。pH值为 6 .8、7.3、7.6时 ,IFN -α2b都能增加ADM抗肿瘤作用 ,但pH值为 7.6时 ,IFN -α2b +ADM杀伤效果最佳。结论 在偏硷性环境下 ,rIL - 2、IFN -α2b、ADM及合用维拉帕米对肿瘤细胞杀伤效果最佳  相似文献   
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5.
2007年5月31日至6月2日,中华医学会肾脏病学分会血液净化论坛在山东省济南市举行,来自全国各地的500余名代表参加了会议。本次论坛收到论文稿403篇,举行了9场大会报告、36场专题报告、3场卫星会议及23个口头报告。会议以透析并发症为主题,同时也对血液透析、腹膜透析及连续性肾脏替代治疗等进行了深人探讨。国内肾脏病学知名专家黎磊石院士、刘志红院士、陈香美教授等作了大会报告,着重阐述了血液净化领域当前面临的主要问题及发展趋势。大会还邀请国际肾脏病学专家Swans教授作了连续性肾脏替代治疗(CRRT)进展的专题报告,以及心血管病专家张运院士作了动脉粥样硬化斑块易损性研究进展的专题报告。  相似文献   
6.
α-L-岩藻糖苷酶测定的临床应用   总被引:1,自引:0,他引:1  
侯振江  张宗英 《华夏医学》2003,16(5):742-743
研究结果表明AFU测定对肝癌的诊断具有较高的敏感性和特异性,其价值优于AFP,两项指标联合检测可提高阳性检出率。动态监测有利于肝癌的早期诊断、鉴别诊断,并可作为转移、复发的指标,也可用于白血病及卵巢癌的诊断。  相似文献   
7.
Veterans who were eligible for dental care in Department of Veterans Affairs (VA) facilities at no monetary cost responded to a mailed questionnaire. Seventy-one percent were aware that they were actually eligible for VA dental care. However, only 48 percent reported the VA as their only or primary source of dental care. Eligibility status, perceived quality of VA dental care, use of VA medical care, perception that one's income meets expenses, and perceived need for dental care were significant correlates of using the VA as one's current source of dental care. Level of formal education, perception that one's income meets expenses, transportation pattern, geographic distance from a VA facility, and eligibility status were significant correlates of using the VA as one's current medical care source. Research on VA utilization offers the opportunity to study issues of access to, and use of, a large public health care system whose patients largely receive care at no monetary cost. Veterans' use of VA dental and medical care is apparently influenced by a wide variety of factors, ranging from barriers to access to non-VA systems, to characteristics of the VA delivery system itself, to need for treatment.  相似文献   
8.
One of the major routes of elimination of dapsone (4,4'-diaminodiphenylsulfone) is by N-oxidation, to produce a hydroxylamine metabolite. The specific form of cytochrome P-450 (P-450) involved in this oxidation reaction was examined in human liver microsomal preparations previously characterized with respect to their content of several known P-450 enzymes. Among five preparations, the rank order of activity for dapsone hydroxylamine formation was most well correlated with the immunochemically determined level of P-4503A4 (r = 0.94, p less than 0.03). Moreover, inhibition of microsomal oxidation was observed with antibodies specific to P-4503A, with a maximum reduction of greater than 90%, but was not produced by antibodies specific to P-4501A2, P-4502CMP, or P-4502E1. Prior incubation of microsomes with gestodene (100 microM) or troleandomycin (20 microM), known selective mechanism-based inhibitors of P-4503A enzymes (in the presence of NADPH), led to 75% and 40% reductions in catalytic activity, respectively. In contrast, preincubation with increasing concentrations of alpha-naphthoflavone, a known activator of P-4503A4, increased dapsone N-hydroxylation in a concentration-dependent manner, with 5-fold activation being observed at 50 microM alpha-naphthoflavone. Finally, P-4503A4 isolated from human liver microsomes and cDNA-expressed P-4503A4 (in yeast) were both able to catalyze dapsone N-hydroxylation, with the latter preparation exhibiting a 3-fold activation in the presence of 100 microM alpha-naphthoflavone. Collectively, these findings demonstrate that N-oxidation of dapsone in human liver is predominantly mediated by P-4503A4, and they suggest that quantitative measurement of this metabolic pathway in vivo might serve as an index of the activity of this enzyme.  相似文献   
9.
In dual-modality PET/CT systems, the CT scan provides the attenuation map for PET attenuation correction. The current clinical practice of obtaining a single helical CT scan provides only a snapshot of the respiratory cycle, whereas PET occurs over multiple respiratory cycles. Misalignment of the attenuation map and emission image because of respiratory motion causes errors in the attenuation correction factors and artifacts in the attenuation-corrected PET image. To rectify this problem, we evaluated the use of cine CT, which acquires multiple low-dose CT images during a respiratory cycle. We evaluated the average and the intensity-maximum image of cine CT for cardiac PET attenuation correction. METHODS: Cine CT data and cardiac PET data were acquired from a cardiac phantom and from multiple patient studies. The conventional helical CT, cine CT, and PET data of an axially translating phantom were evaluated with and without respiratory motion. For the patient studies, we acquired 2 cine CT studies for each PET acquisition in a rest-stress (13)N-ammonia protocol. Three readers visually evaluated the alignment of 74 attenuation image sets versus the corresponding emission image and determined whether the alignment provided acceptable or unacceptable attenuation-corrected PET images. RESULTS: In the phantom study, the attenuation correction from helical CT caused a major artifactual defect in the lateral wall on the PET image. The attenuation correction from the average and from the intensity-maximum cine CT images reduced the defect by 20% and 60%, respectively. In the patient studies, 77% of the cases using the average of the cine CT images had acceptable alignment and 88% of the cases using the intensity maximum of the cine CT images had acceptable alignment. CONCLUSION: Cine CT offers an alternative to helical CT for compensating for respiratory motion in the attenuation correction of cardiac PET studies. Phantom studies suggest that the average and the intensity maximum of the cine CT images can reduce potential respiration-induced misalignment errors in attenuation correction. Patient studies reveal that cine CT provides acceptable alignment in most cases and suggest that the intensity-maximum cine image offers a more robust alternative to the average cine image.  相似文献   
10.
Food-deprived pigeons were trained to peck a key under either a three-component multiple random-ratio 5, random-ratio 25, random-ratio 125 schedule or a three-component multiple random-interval 10-sec, random-interval 30-sec, random-interval 125-sec schedule of food presentation. Following determination of acute effects of cocaine (1.0-13.0 mg/kg), are-sponse-rate-reducing dose was given before each daily session. Once performance under conditions of daily administration had become stable, other doses occasionally were substituted for the usual daily dose so that dose effects could be assessed. Tolerance, i.e., a rightward shift in the dose-effect curve was observed in all subjects. For subjects studied under the random-ratio schedules, however, the robustness of the tolerance usually was related to the schedule-parameter value; tolerance was great at lower random values. By contrast, subjects whose responding was maintained by random-interval schedules were less likely to show tolerance that was schedule-parameter dependent. The results also provide suggestive evidence that dose may be an important factor in determining effects of repeated cocaine exposure; repeated administration of larger doses may be less likely to result in tolerance than similar exposure to smaller doses.  相似文献   
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