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91.
S. Patel S. Lu P. C. Doerschuk G. R. Wodicka 《Medical & biological engineering & computing》1995,33(4):571-574
A parametric phase delay estimation technique is used to determine the spatial and inhaled gas composition dependencies of
sound propagation time through an intact human lung at frequencies of 150–1200 Hz. Noise transmission measurements from the
mouth to the extrathoracic trachea and six sites on the posterior chest wall are performed in 11 healthy adult subjects at
resting lung volume after equilibration with air, an 80% helium-20% oxygen mixture, and an 80% sulfurhexafluoride-20% oxygen
mixture. The phase delay, τ(f), exhibits a bilateral asymmetry with relatively decreased delays to the left posterior chest
as compared with the right. The phase delay to lower lung sites is greater than to upper sites at frequencies below 300 Hz;
yet the opposite is found at higher frequencies, indicating changing propagation pathways with frequency. There is no measurable
effect of inhaled gas composition on τ(f) below 300 Hz. At higher frequencies, changes in τ(f) that reflect the relative sound
speed of the particular inhaled gas are observed. These findings support and extend previous measurements and hypotheses concerning
the strong frequency dependence of the acoustical properties of the intact respiratory system. 相似文献
92.
We report on the antileukemia effect of interleukin 2 (IL2) on different immune cells from 22 patients with chronic myeloid leukemia (CML). Bone marrow cells from these patients were first cultured in modified long-term bone marrow culture medium for several days, then separately cultured with lymphokine activated killer cells (LAK), cytokine-induced killer cells (CIK), and dendritic cell cocultured CIK (DC-CIK) for another 1-2 days. They were then detected for presence of the Philadelphia chromosome (Ph) by cytogenetic analysis and fluorescence in situ hybridization (FISH). The percentage of Ph-chromosome-positive cells in the bone marrow mononuclear cells after culturing with CIK and DC-CIK was significantly lower than that after culturing with IL2 or LAK. Our results demonstrate that cytogenetics and FISH are useful techniques for the evaluation of the anti-CML effect of immune cells and that CIK or DC-CIK can be appropriate candidates for adoptive immune cell therapy in vivo or for leukemia cell purging ex vivo. 相似文献
93.
Pelvic radiation with concurrent chemotherapy compared with pelvic and para-aortic radiation for high-risk cervical cancer 总被引:55,自引:0,他引:55
Morris M Eifel PJ Lu J Grigsby PW Levenback C Stevens RE Rotman M Gershenson DM Mutch DG 《The New England journal of medicine》1999,340(15):1137-1143
BACKGROUND AND METHODS: We compared the effect of radiotherapy to a pelvic and para-aortic field with that of pelvic radiation and concurrent chemotherapy with fluorouracil and cisplatin in women with advanced cervical cancer. Between 1990 and 1997, 403 women with advanced cervical cancer confined to the pelvis (stages IIB through IVA or stage IB or IIa with a tumor diameter of at least 5 cm or involvement of pelvic lymph nodes) were randomly assigned to receive either 45 Gy of radiation to the pelvis and para-aortic lymph nodes or 45 Gy of radiation to the pelvis alone plus two cycles of fluorouracil and cisplatin (days 1 through 5 and days 22 through 26 of radiation). Patients were then to receive one or two applications of low-dose-rate intracavitary radiation, with a third cycle of chemotherapy planned for the second intracavitary procedure in the combined-therapy group. RESULTS: Of the 403 eligible patients, 193 in each group could be evaluated. The median duration of follow-up was 43 months. Estimated cumulative rates of survival at five years were 73 percent among patients treated with radiotherapy and chemotherapy and 58 percent among patients treated with radiotherapy alone (P=0.004). Cumulative rates of disease-free survival at five years were 67 percent among patients in the combined-therapy group and 40 percent among patients in the radiotherapy group (P<0.001). The rates of both distant metastases (P<0.001) and locoregional recurrences (P<0.001) were significantly higher among patients treated with radiotherapy alone. The seriousness of side effects was similar in the two groups, with a higher rate of reversible hematologic effects in the combined-therapy group. CONCLUSIONS: The addition of chemotherapy with fluorouracil and cisplatin to treatment with external-beam and intracavitary radiation significantly improved survival among women with locally advanced cervical cancer. 相似文献
94.
Lu Y Condie A Bennett JD Fry MJ Yuille MR Shipley J 《Cancer Genetics and Cytogenetics》2001,126(2):97-101
Mutations in the ATM gene, which maps to 11q22-23, cause the multisystem recessive syndrome ataxia-telangiectasia (AT). Breast cancer has been reported in AT patients and carriers. Sporadic breast cancer is associated with loss of heterozygosity at or in the region of ATM and chromosomal abnormalities involving 11q23. We have investigated the chromosomes, nuclei and released chromatin fibers from nine primary breast carcinoma and eight cell lines by fluorescence in situ hybridization with four fluorochrome-labeled cosmids spanning the ATM gene. The ATM gene was disrupted in one primary breast carcinoma and in the cell lines MDA-MB-231 and MCF-7. The role of these aberrations in breast carcinomas, which may lead to gene dosage or dominant negative effects on gene function, requires further investigation. 相似文献
95.
Ha-VP39 binding to actin and the influence of F-actin on assembly of progeny virions 总被引:3,自引:0,他引:3
Summary We present evidence that actin is necessary for the successful assembly of HaNPV virions. Purified nucleocapsid protein Ha-VP39 of Heliothis armigera nuclear polyhedrosis virus (HaNPV) was found to be able to bind to actin in vitro without assistance, as demonstrated by Western blot and isothermal titration calorimeter. H and binding constants (K) detected by isothermal titration calorimeter strongly suggested that Ha-VP39 first binds actin to seed the formation of hexamer complex of actin, and the hexamers then link to each other to form filaments, and the filaments finally twist into cable structures. The proliferation of HaNPV was completely inhibited in Hz-AM1 cells cultivated in the medium containing 0.5µg/ml cytochalasin D (CD) to prevent polymerization of actin, while its yield was reduced to 10–4 in the presence of 0.1µg/ml CD. Actin concentration and the viral DNA synthesis were not significantly affected by CD even though the progeny virions assembled in the CD treated cells were morphologically different from normal ones and resulted in fewer plaques in plaque assayThe authors equally contributed to the work.The authors equally contributed to the work. 相似文献
96.
Molecular epidemiological and clinical aspects of hepatitis D virus in a unique triple hepatitis viruses (B,C, D) endemic community in Taiwan 总被引:2,自引:0,他引:2
The molecular epidemiological and clinical aspects of hepatitis D virus (HDV) in a unique HBV, HCV, and HDV triple virus endemic community in southern Taiwan were investigated. A total of 2,909 residents aged 45 or older were screened for hepatitis B surface antigen (HBsAg), anti-HCV antibody, and anti-HDV antibody (specifically for HBsAg-positive carriers). Factors that might be associated with HDV infection, viral nucleic acid detection, and genotyping of HBV, HCV, and HDV were investigated. The prevalence of HBsAg and anti-HCV were 12.6% (366/2,909) and 41.6% (1,227/2,909), respectively. For HBsAg carriers, 15.3% (56/366) were positive for anti-HDV assay. Living in a higher endemic district of HCV infection (odds ratio [OR] = 3.2; 95% confidence interval [CI] = 1.7-6.3), male gender (OR = 1.9; 95% CI = 1.1-3.6) and co-infection with HCV (OR = 1.8; 95% CI = 1.0-3.3) were significantly independent factors associated with HDV infection. The detection rate of HDV RNA among anti-HDV-positive patients was only 12.7% (7/55). The mean HBV titer of triple infection group was significantly lower than in the HBV/HDV co-infection group (2.23 vs 3.05 in log(10), copies/ml, P = 0.046). HCV RNA detection among the triple infection group showed 47.4% (9/19) viremia rate and viral loads of 579,121 IU/ml in median (16,803-1,551,190 IU/ml). The prevalent genotype of HBV was type B (23/25); HCV was 1b (7/9) and HDV was IIa/IIb (4/4). Only the presence of HCV RNA predicted the presence of elevated ALT significantly (OR = 25.0; 95% CI = 3.39-184.6). In conclusion, the geographical aggregation of HDV infection paralleled that of HCV infection in this community. HCV suppressed the replication of HBV among triple vital infection patients. HBV and HDV lapsed into a remission or nonreplicative phase in most cases, and HCV acted as a dominant factor in triple viral-infected individuals. Only the presence of HCV RNA was associated with elevated ALT values, but not HBV or HDV. 相似文献
97.
Under the condition of obvious iron-overload, there is a zonal hernoeiderin (iron) deposition in hepatic lobules. The deposition is heavtest in the periporfal (zone 1) and lightest in the perivenws (zone 3) hepatocytes. However, the mechanism for this pattern of iron deposition is obscure. Hepatic tissues from control, iron-deficlent or ironoverloaded Wistar rats me used to study its pathogenesis. iron-deficiency was Induced by a low Iron regimen. Ironoverload was produced by repeated intraperitoneal injections of ferric nitrilotriace-We (Fe3+ -NTA) for 1–4 months. Liver tissues of the rats were lmmunohistochemically and histochemically stained for tmnaferrin receptor (TfR), transferrin (Tf), ferritin (Ft), and iron. The staining intensity of TfR, Tf and Ft increased in hepatocytes of iron-deflctent rats and decreased in that of the iromverloaded in comparison with the control rats. TfR atalning was strong in zone 1, with gradual transition into weak staining in zone 3 hepatocytes of the rat liver. TfR located primarily on the hepatocyte membrane. Tf had both membranous and cytoplasmic distribution. Many hepatocytes in group B had strong cytoplasmic Tf staining. Conversely, only a few hepatocytes had weakly stained cytoplasmic Tf in group C. Hepatocytes and Kupffer cells were Ft positive in control rats. Ft was distributed only in the cytoplasm. The staining intensity of Ft was stronger in zone 3 than in zone 1 hepatocytes of iron-deficient rats. In iron-overloaded rats, the iron deposition was severe in zone 1 and mild in zone 3 hepatocytes. These findings suggest that uptake of iron into hepatocytes in vivo is regulated and mediated by TfR and Tf. Gradient TfR distribution from zone 1 to 3 hepatocytes and active TfR-Tf mediated iron uptake resuited in the zonal iron deposition in the hepatic lobule of iron-overloaded rats. 相似文献
98.
99.
Lupus-related advanced liver involvement as the initial presentation of systemic lupus erythematosus. 总被引:1,自引:0,他引:1
Ming-Chi Lu Ko-Jen Li Song-Chou Hsieh Cheng-Han Wu Chia-Li Yu 《Journal of microbiology, immunology, and infection》2006,39(6):471-475
BACKGROUND AND PURPOSE: Systemic lupus erythematosus (SLE), a prototype of systemic autoimmune disease characterized by multiorgan involvement with diverse clinical and serological manifestations, principally affects women in their child-bearing years. Clinically significant hepatic abnormality as the initial presentation of SLE has rarely been reported. METHODS: Eleven patients with lupus with initial presentation of lupus-related hepatitis were included in this retrospective review. Clinical manifestation, immunological profiles, and risk factors for poor prognosis were analyzed. RESULTS: The most commonly associated clinical manifestations were found to be thrombocytopenia, leukopenia, advancing age, and presence of anti-SSA/Ro antibody and anti-thyroid antibodies. The diagnosis of SLE was delayed due to dominant hepatic abnormalities. Age greater than 50 years and marked hepatic decompensation in accordance with Child classification B and C might suggest poor prognosis (p=0.06). However, the p value was not statistically significant because of the small sample size. CONCLUSIONS: Lupus-related hepatitis, particularly in late-onset lupus, is common. In addition, the presence of anti-SSA, anti-thyroglobulin, and anti-microsomal antibodies is indicative of hepatic involvement in patients with SLE. 相似文献
100.
Z Y Lu J Brochier J Wijdenes H Brailly R Bataille B Klein 《European journal of immunology》1992,22(11):2819-2824
A patient with plasma cell leukemia was treated with anti-interleukin (IL)-6 monoclonal antibodies (mAb) for 2 months. Using chromatography on protein A-Sepharose, anti-murine-IgG-Sepharose, anti-IL-6-mAb-Sepharose and gel filtration at pH 2.3, we have demonstrated that the anti-IL-6 mAb, by preventing the binding of IL-6 to its cell membrane receptor and its renal elimination, has induced huge amounts of IL-6 to circulate in the form of monomeric immune complexes. By using this observation, we have developed a mathematical modelling that allows the determination of the overall daily production of IL-6 in this patient, which was in the range of 15 micrograms per day. Overall in vivo production of cytokines has never been evaluated in animals or in humans before. 相似文献