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排序方式: 共有408条查询结果,搜索用时 15 毫秒
81.
Reed-Sternberg cells in Hodgkin's disease contain fibronectin 总被引:6,自引:0,他引:6
Reed-Sternberg cells in the lymph nodes from five patients with Hodgkin's disease were studied. Indirect immunofluorescence on fixed sections with a monospecific anti-serum to fibronectin revealed abundant cytoplasmic fibronectin in approximately 90% of the Reed- Sternberg cells. In addition, the cells were shown by immunofluorescence to contain polyclonal IgG; however, factor VIII antigen, albumin, fibrinogen, alpha-2-macroglobulin, anti-thrombin III, and ceruloplasmin were not present. The abundant cytoplasmic fibronectin suggests that Reed-Sternberg cells are derived from tissue macrophages. 相似文献
82.
Serum hepatitis B surface antigen correlates with fibrosis and necroinflammation: A multicentre perspective in China 下载免费PDF全文
P. Zhang HB. Du GD. Tong XK. Li XH. Sun XL. Chi YF. Xing ZH. Zhou Q. Li B. Chen H. Wang L. Wang H. Jin DW. Mao XB. Wang QK. Wu FP. Li XY. Hu BJ. Lu ZY. Yang MX. Zhang WB. Shi Q. He Y. Li KP. Jiang JD. Xue XD. Li JM. Jiang W. Lu GJ. Tian ZB. Hu JC. Guo CZ. Li X. Deng XL. Luo FY. Li XW. Zhang YJ. Zheng G. Zhao LC. Wang JH. Wu H. Guo YQ. Mi ZJ. Gong CB. Wang F. Jiang P. Guo XZ. Yang WQ. Shi HZ. Yang Y. Zhou NN. Sun YT. Jiao YQ. Gao DQ. Zhou YA. Ye 《Journal of viral hepatitis》2018,25(9):1017-1025
The kinetics of serum hepatitis B surface antigen (HBsAg) during the natural history of hepatitis B virus (HBV) infection has been studied, but the factors affecting them remain unclear. We aimed to investigate the factors affecting HBsAg titres, using data from multicentre, large‐sized clinical trials in China. The baseline data of 1795 patients in 3 multicentre trials were studied, and the patients were classified into 3 groups: hepatitis B early antigen (HBeAg)‐positive chronic HBV infection (n = 588), HBeAg‐positive chronic hepatitis B (n = 596), and HBeAg‐negative chronic hepatitis B (n = 611). HBsAg titres in the different phases were compared, and multiple linear progression analyses were performed to investigate the implicated factors. HBsAg titres varied significantly in different phases (P = .000), with the highest (4.60 log10 IU/mL [10%‐90% confidence interval: 3.52 log10 IU/mL‐4.99 log10 IU/mL]) in patients with HBeAg‐positive chronic HBV infection. In all phases, age and HBV DNA were correlated with serum HBsAg level. In HBeAg‐positive chronic hepatitis B patients, a negative correlation between HBsAg titres and fibrosis stage was observed. Alanine amonitransferase or necroinflammatory activity was also correlated with HBsAg titres in HBeAg‐negative chronic hepatitis B patients. In conclusion, decreased HBsAg titres may be associated with advancing fibrosis in HBeAg‐positive chronic hepatitis B patients or increased necroinflammation in those with HBeAg‐negative chronic hepatitis B. Our findings may help clinicians better understand the kinetics of HBsAg and provide useful insights into the management of this disease. 相似文献
83.
P. Zhang HB. Du GD. Tong XK. Li XH. Sun XL. Chi YF. Xing ZH. Zhou Q. Li B. Chen H. Wang L. Wang H. Jin DW. Mao XB. Wang QK. Wu FP. Li XY. Hu BJ. Lu ZY. Yang MX. Zhang WB. Shi Q. He Y. Li KP. Jiang JD. Xue XD. Li JM. Jiang W. Lu GJ. Tian ZB. Hu JC. Guo CZ. Li X. Deng XL. Luo FY. Li XW. Zhang YJ. Zheng G. Zhao LC. Wang JH. Wu H. Guo YQ. Mi ZJ. Gong CB. Wang F. Jiang P. Guo XZ. Yang WQ. Shi HZ. Yang Y. Zhou NN. Sun YT. Jiao YQ. Gao DQ. Zhou YA. Ye 《Journal of viral hepatitis》2018,25(9):ii-ii
84.
Plasminogen activator inhibitor: a regulator of ancrod-induced fibrin deposition in rabbits 总被引:2,自引:0,他引:2
Plasma levels of a fast-acting plasminogen activator inhibitor (PAI), which neutralizes both tissue plasminogen activator (t-PA) and urokinase, are markedly increased in endotoxin-treated rabbits. The ability of this inhibitor to prevent the fibrinolysis that occurs after a thrombogenic stimulus was investigated in a rabbit model. Normal and endotoxin-treated male New Zealand rabbits were infused with ancrod, an enzyme that causes noncrosslinked fibrin formation in vivo. Ancrod stimulated t-PA activity by 90% in normal rabbits and caused hypofibrinogenemia but did not increase PAI levels or induce fibrin deposition in target organs. Rabbits injected with endotoxin (10 micrograms/kg) showed an increase in PAI from less than 1 to 32 U/mL 4 hours later. When ancrod was infused at this time, 90% of the rabbits developed renal fibrin thrombi. Fibrin deposition was recorded in 40% of the rabbits that received a lower dose of endotoxin (1.0 microgram/kg) and had a PAI level of 14 U/ml at the time of ancrod infusion 4 hours later. Fibrin deposition did not occur in the endotoxin-treated rabbits that received normal saline. These data suggest that high levels of PAI inhibit fibrinolysis in vivo, thereby promoting fibrin clot deposition following a thrombogenic stimulus. 相似文献
85.
Ehrlich GD; Glaser JB; LaVigne K; Quan D; Mildvan D; Sninsky JJ; Kwok S; Papsidero L; Poiesz BJ 《Blood》1989,74(5):1658-1664
The extent of human T-cell leukemia/lymphoma virus type II (HTLV-II) infection and its rate of spread have been difficult to determine owing to the serological cross-reactivity between HTLV-I and HTLV-II. The present study overcame this problem by directly detecting type-specific proviral sequences by means of the polymerase chain reaction (PCR) and liquid hybridization. Screening was performed on a cohort of primarily white intravenous drug abusers (IVDAs), and individuals of other behaviorally defined risk groups from the New York City area. Eleven percent (19 of 169) of the individuals in these high-risk groups were determined by PCR to have HTLV-II proviral infections. One of these patients displayed an exfoliative erythrodermatitis. Thirteen of the 19 subjects were positive in an HTLV-II enzyme-linked immunosorbent assay (ELISA). The remaining six individuals, although negative in the HTLV- II ELISA, were confirmed as HTLV-II positive by analyzing their DNA with a second HTLV-II-specific primer detector system. Four additional individuals were reactive in the HTLV-II ELISA but were PCR-negative for HTLV-II. PCR analysis for HTLV-I revealed that all four were positive for that virus. Thirty-seven percent (seven of 19) of the HTLV- II PCR-positive subjects were also PCR-positive for HTLV-I, and 84% (16 of 19) of the HTLV-II positive individuals were infected with human immunodeficiency virus (HIV-1). Six individuals were triply infected with HTLV-I, HTLV-II, and HIV-1. 相似文献
86.
Immunologic characterization of a helper T-cell lymphoma 总被引:3,自引:0,他引:3
The lymphocytes of a patient with a T-cell non-Hodgkin's lymphoma with peripheral blood involvement and polyclonal hypergammaglobulinemia were characterized in terms of surface markers and immunologic functions. Using the fluorescence-activated cell sorter and employing various monoclonal antibodies against T-cell surface antigens, it was shown that almost all of the patient's peripheral blood lymphocytes were positive for OKT4 and 9.3, antibodies that recognize helper T-cell subset. The circulating lymphoma cells had typical characteristics for T cells; they formed spontaneous rosettes with sheep erythrocytes and stained with the pan-T-cell antibodies 9.6 and 10.2, but did not react with other anti-T-cell monoclonal reagents such as OKT3, UCHT-1, and 3A1. The cells appeared to be mature by the fact that they did not stain with OKT6, and terminal deoxynucleotidyl transferase was undetectable. Functionally, they were able to provide "help" for antibody production, and they could be stimulated to produce moderate amounts of interleukin-2, while unable to proliferate in response to mitogens. Morphologically, some of the lymphocytes showed a deeply cleaved nucleus. 相似文献
87.
Snyder DS; Chao NJ; Amylon MD; Taguchi J; Long GD; Negrin RS; Nademanee AP; O'Donnell MR; Schmidt GM; Stein AS 《Blood》1993,82(9):2920-2928
Ninety-nine consecutive patients with acute leukemia in first complete remission under age 50 (median age 27 years; age range 1 to 47 years) with a histocompatible sibling donor were treated with fractionated total body irradiation (1,320 cGy) and high-dose etoposide (60 mg/kg) followed by allogeneic bone marrow transplantation. Sixty-one patients were diagnosed with acute myelogenous leukemia (AML), 34 patients with acute lymphoblastic leukemia (ALL), 3 patients with biphenotypic acute leukemia, and 1 patient with acute undifferentiated leukemia. Thirty of the 34 patients with ALL had at least one of the following high-risk factors: age greater than 30, white blood cell count at presentation > 25,000/microL, extramedullary disease, certain chromosomal translocations, or the need for greater than 4 weeks of induction chemotherapy to achieve first complete remission. Cumulative probabilities of disease-free survival and relapse at 3 years were 61% and 12%, respectively, for the 61 patients with AML and 64% and 12%, respectively, for the 34 patients with ALL. By stepwise Cox regression analysis, significant prognostic variables for patients with acute myelogenous leukemia were the presence of acute graft-versus-host disease and increasing age, whereas for patients with acute lymphoblastic leukemia, significant variables were age and the development of cytomegalovirus-associated interstitial pneumonia. Complications related to graft-versus-host disease and relapse of leukemia were the major causes of death. 相似文献
88.
Cogan's syndrome with Takayasu's arteritis 总被引:1,自引:1,他引:1
Cogan's syndrome may be associated with large-vessel arteritis. We describe
a patient with ocular inflammation, sensorineural hearing loss and arm
claudication in whom a diagnosis of 'atypical' Cogan's syndrome and
Takayasu's arteritis was made. All symptoms resolved with treatment.
相似文献
89.
Subsecond calcium dynamics in ADP- and thrombin-stimulated platelets: a continuous-flow approach using indo-1 总被引:2,自引:2,他引:2
The regulation and kinetics (less than 5 seconds) of cytosolic calcium changes ([Ca2+]i) in stimulated blood platelets have been investigated under physiological blood flow conditions. Using a newly-developed continuous-flow approach with indo-1-loaded human platelets, adenosine diphosphate (ADP, 10 mumol/L) and thrombin (5 U/mL) were equally effective in significantly increasing [Ca2+]i by 0.5 seconds. ADP induced a transient [Ca2+]i peak of 1 to 2 mumol/L near 2 seconds, whereas thrombin caused a sustained and larger response. The first phase (less than 2 seconds) was not influenced by a lack of extracellular Ca2+, in contrast to the subsequent [Ca2+]i increase that only reached about 0.7 mumol/L for either ADP or thrombin. The shear rates used in our continuous-flow apparatus were physiological (less than 1,258 sec-1) and only slightly increased the basal [Ca2+]i of 0.1 mumol/L. Platelet aggregation (less than 5 seconds), assessed by single- particle counting, was not altered in platelets loaded with indo-1/AM (2.5 mumol/L). 相似文献
90.
The Philadelphia (Ph1) chromosome, characteristic of chronic myelogenous leukemia (CML), arises from a reciprocal translocation between chromosomes 9 and 22. The site of the breakpoint on chromosome 22 is within a small region called the breakpoint cluster region (bcr). We have mapped the breakpoint within the bcr in peripheral blood leukocyte DNA from 22 Ph1-positive CML patients. No correlation between the site of the breakpoint and the clinical phase of the disease was found. However, a striking correlation between the site of the breakpoint and the length of time between presentation and onset of acute phase was observed: on average, patients with a 5' break-point had a fourfold longer chronic phase (median, 203 weeks) than those with a 3' breakpoint (median, 52 weeks). 相似文献