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81.
82.
对SARS抗体动态水平的系统观察 总被引:2,自引:1,他引:1
目的应用化学发光光度分析法对SARS抗体(SARS-Ab)动态水平进行观察.方法对432例SARS病人在恢复期的不同阶段进行检测.结果显示SARS病人的抗体检出率为94.0%(404/432).病人SARS-Ab在2,3,4周和2个月时,抗体检出平均光子数值为3.79,7.71,12.31和24.17;3~8个月SARS-Ab下降率分别为92.9%,83.3%,40.0%,26.7%,13.3%和7.0%.结论病人在患病初期,SARS-Ab呈上升趋势,3个月后逐渐下降,并能动态观察不同年龄组SARS-Ab的明显差异. 相似文献
83.
84.
Joe I-Chiang Chou Hwai-Jen Fong Shou-Hsin Kuang Lin-Yang Gi Fang-Yi Hwang Yu-Chieng Lai Richard Che-Shoa Chang Shou-Yen Kao 《Journal of oral and maxillofacial surgery》2005,63(3):355-361
PURPOSE: This study was an analysis of the soft and hard tissue changes of the facial profile after bilateral sagittal splitting osteotomy for mandibular setback of Taiwanese patients. PATIENTS AND METHODS: We collected pre- and postsurgical lateral cephalographs of 64 patients (28 males, 36 females) with skeletal Class III malocclusion who received combined orthodontic-surgical treatment with bilateral sagittal splitting osteotomy mandibular setback at Taipei Veterans General Hospital between 1994 and 2000. Nineteen cephalometric parameters of (14 linear, 4 angular, and the BS index) soft and hard tissues were measured at 1 week before treatment, and 2 months and 1 year after surgery, and analyzed by paired t test. RESULTS: Mean patient age was 20.0 +/- 1.6 years. The patients underwent an average of 7 mm mandibular setback at the osseous pogonion (Pog). Average setbacks at Pog and soft tissue pogonion (pog) were 5.54 mm and 4.85 mm, respectively, at 1 year after surgery. The setback ratio of Pog/pog was 1:0.88. The hard tissue relapse at Pog was 21% at 1 year after surgery. Improvement in prognathic profile was demonstrated by significant changes in the positions of Pog and pog, ANB angle, the distance from lower lip to esthetic line (E-L lip), and the BS index after surgery. However, compared with parameters obtained from a normal Taiwanese population, the cephalometric data of Pog, pog, and BS index still indicated mild prognathism. CONCLUSION: Although mandibular prognathism could be grossly improved by bilateral sagittal splitting osteotomy mandibular setback, a significant amount of relapse occurred within 1 year after surgery. The extent of the postoperatively preserved features showing mandibular prognathism should be a concern for both patients and physicians. 相似文献
85.
86.
S. T. Fan Q. S. Wang C. M. Lo K. W. Tam Yu E. C. S. Lai J. Wong 《ANZ journal of surgery》1994,64(11):759-762
Impaired hepatic function is a major contributory factor to the high incidence of postoperative morbidity and mortality in patients with malignant biliary obstruction. Dynamic hepatic function tests such as indocyanine green (ICG) retention and aminopyrine breath tests were evaluated in such patients to define whether they were clinically useful for prediction of postoperative morbidity and mortality. Forty-four patients with malignant biliary obstruction undergoing surgery for relief of obstructive jaundice were recruited into the study. Indocyanine green retention and aminopyrine breath tests were carried out in all patients pre-operatively and repeated in 36 patients postoperatively. The ICG retention was abnormal in all patients before surgery and there was significant improvement 2 weeks after surgery (32.8 ± 2.5%vs 18.3 ± 2.8%, P= 0.001). The change in ICG retention levels correlated with the serum bilirubin levels but the pre-operative ICG retention value could not predict postoperative morbidity and mortality. The aminopyrine breath test was abnormal in all but one patient. It correlated with pre-operative prothrombin time of the patients before surgery but it did not improve significantly after surgery and was not predictive of postoperative outcome. It is concluded that both ICG retention and aminopyrine breath tests have limited clinical value in the pre-operative evaluation of patients with malignant biliary obstruction. 相似文献
87.
Benzo(a)pyrene inhibits epidermal growth factor binding and receptor autophosphorylation in human placental cell cultures 总被引:1,自引:0,他引:1
H J Guyda L Mathieu W Lai D Manchester S L Wang S Ogilvie K T Shiverick 《Molecular pharmacology》1990,37(2):137-143
Studies investigated the effects of benzo(a)pyrene (BP) treatment on epidermal growth factor (EGF) receptor binding and kinase activity in human placental cell cultures. Specific binding of 125I-EGF to cells from early gestation placentae was significantly decreased by 37 and 60% following exposure to 1 and 10 microM BP, respectively, for 24 hr. In contrast, cells cultured from term placentae showed no inhibitory effect of either concentration of BP. Specific binding of 125I-labeled insulin and insulin-like growth factors-I and -II to early gestation cells was decreased only 15-18% at 10 microM BP, which indicates that loss of membrane receptors appears to be selective for EGF. Scatchard analysis of early gestation cells revealed that BP was associated with a dose-dependent loss in the number of high affinity EGF binding sites. Evidence from cross-linking and autophosphorylation experiments confirmed that the Mr 170,000 binding protein was decreased in a dose-dependent manner following BP treatment. In comparison, term placental cells exhibit a 26% loss of EGF receptor autophosphorylation without alteration in binding following exposure to 10 microM BP. Thus, early gestation cells exhibit a BP-related down-regulation of EGF receptors, whereas term placental cells show receptor desensitization. No adverse effect of BP treatment was observed on the incorporation of [35S] methionine into proteins secreted by early gestation cells. Further experiments compared the effects of BP with the related poly-cyclic compounds beta-naphthoflavone, alpha-naphthoflavone, and 3-methylcholanthrene. In early gestation cells, EGF binding and receptor autophosphorylation were measurably decreased at 10 microM concentrations of these polycyclic compounds, but to a lesser extent than observed with BP. In term placental cells, however, EGF binding was unchanged or increased, whereas receptor autophosphorylation was decreased 10-26%. Thus, exposure of term placental cells to these polycyclic compounds leads to a dissociation between EGF binding and receptor protein kinase activity. Finally, aryl hydrocarbon hydroxylase activity was induced 20- to 200-fold in early placental cells exposed to BP, beta-naphthoflavone, and 3-methylcholanthrene. In summary, the direct effects of BP and related compounds observed on placental EGF receptors may indicate altered function of EGF in the regulation of cell growth and differentiation in the human placenta. 相似文献
88.
Identifying potential indicators of the quality of end-of-life cancer care from administrative data.
Craig C Earle Elyse R Park Bonnie Lai Jane C Weeks John Z Ayanian Susan Block 《Journal of clinical oncology》2003,21(6):1133-1138
PURPOSE: To explore potential indicators of the quality of end-of-life services for cancer patients that could be monitored using existing administrative data. METHODS: Quality indicators were identified and assessed by literature review for proposed indicators, focus groups with cancer patients and family members to assess candidate indicators and generate new ideas, and an expert panel ranking the meaningfulness and importance of each potential indicator using a modified Delphi approach. RESULTS: There were three major concepts of poor quality of end-of-life cancer care that could be examined using currently-available administrative data (such as Medicare claims): institution of new anticancer therapies or continuation of ongoing treatments very near death; a high number of emergency room visits, inpatient hospital admissions, or intensive care unit days near the end of life; and a high proportion of patients never enrolled in hospice, only admitted in the last few days of life, or dying in an acute-care setting. Concepts such as access to psychosocial and other multidisciplinary services and pain and symptom control are important and may eventually be feasible, but they cannot currently be applied in most data systems. Indicators based on limiting the use of treatments with low probability of benefit or indicators based on economic efficiency were not acceptable to patients, family members, or physicians. CONCLUSION: Several promising claims-based quality indicators were identified that, if found to be valid and reliable within data systems, could be useful in identifying health-care systems in need of improving end-of-life services. 相似文献
89.
目的:探讨应对压力的方式与腹膜透析患者的焦虑抑郁情绪的关系。方法:采用自填式结构问卷,对81例腹膜透析患者进行调查,了解患者的一般情况和患者应对措施,同时用综合性医院焦虑和抑郁情绪量表测量他们的焦虑与抑郁情绪。结果:控制年龄等因素后的等级回归分析表明:使用“面对”和“自我缓解”应对方式显著降低患者的焦虑情绪,采用“屈从”应对方式增加焦虑的发生;文化程度高的患者采用逃避应对方式则大大增加焦虑情绪的程度,女性和经济收入高者采用面对应对方式可以大大降低焦虑情绪的发生;“自我缓解”应对方式显著降低患者抑郁情绪发生的可能性。结论:不同的应对方式对腹膜透析患者的焦虑抑郁情绪存在差异。 相似文献
90.
Jong-Kai Hsiao Ming-Fong Tai Hung-Hao Chu Shin-Tai Chen Hung Li Dar-Ming Lai Sung-Tsang Hsieh Jaw-Lin Wang Hon-Man Liu 《Magnetic resonance in medicine》2007,58(4):717-724
The purpose of this work was to evaluate the efficacy of labeling human mesenchymal stem cells (hMSCs) by ionic superparamagnetic iron oxide (SPIO) without a transfection agent and verifying its capability to be detected with clinical 1.5 T magnetic resonance (MR) at the single-cell level. Human hMSCs were incubated for 24 h with an ionic SPIO, Ferucarbotran. The labeling efficiency of hMSCs was determined by iron content measurement spectrophotometrically, and the influence of labeling on cell behavior was ascertained by examination of cell viability using the trypan blue exclusion method, cell proliferation analysis using MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay, mitochondrial membrane potential (MMP) change, differentiation capacity, and reactive oxygen species (ROS) production measured by dichlorofluorescein diacetate (DCFDA) fluorescent probe. Labeled hMSCs were scanned under 1.5 T MRI with three-dimensional (3D) and two-dimensional (2D) T(2)-weighted gradient echo (GRE) pulse sequences. Human hMSC labeling without transfection agent was efficient. The iron content in hMSCs was 23.4 pg Fe/cell. No significant change was found in viability, proliferation, MMP change, ROS production, or differentiation capacity. About 45.2% of the hMSCs could be detected using 1.5 T MRI at the single cell level with 3D GRE and four repetitions. 相似文献