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111.
HemorrhagicfeverwithrenalsyndromevirusinfectioninliversstudiedbyinsituhybridizationandimmunohistochemistryYangShoujing(杨守京);L... 相似文献
112.
对60例病毒性肝炎患者进行肝穿刺活检,结果发现,临床与病理诊断的符合率为46.6%,其中,急性肝炎的诊断符合率最低(23.8%),慢性迁延型肝炎(慢迁肝)为44.8%;HBsAg阳性首次发病的患者中,急性乙型肝炎仅为11.2%(2/18);临床诊断的慢性活动型肝炎(慢活肝)仅为病理检出的25.7%(9/35);肝炎患者中脾肿大,凝血酶元时间延长、A/G值<1.2、抗HBcIgM阳性可作为慢活肝与慢迁肝鉴别的重要指标。这些对提高病毒性肝炎临床分型诊断的准确率及指导临床治疗有意义。 相似文献
113.
重症肌无力病人乙酰胆碱受体抗体的测定及临床意义 总被引:7,自引:0,他引:7
用ELISA(固相酶联免疫吸附)法测定172例MG病人血清乙酰胆碱受体抗体(AchRab),结果显著高于健康献血员组和非MG病人组。不同性别、病程及临床类型与AchRab无相关性,但41~50岁组的显著高于其他年龄组。67例类固醇激素治疗组、22例大剂量两种球蛋白治疗组、12例胸腺切除术组及3例MG危象病人24次血浆交换疗法(PE)组,治疗后伴随肌无力症状的好转,AchRab均显著低于治疗前。结果表明:AchRab测定为MG诊断提供了可靠的实验依据,为类固醇激素、大剂量丙种球蛋白、胸腺切除术和PE等治疗MG提供理论依据和疗效评定的实验指标,进一步证实了MG免疫学发病机理。 相似文献
114.
Erythromycin administration has been associated with a prolongation of cardiac repolarization in certain clinical settings.
This could be due to blockade of voltage-dependent K+ channels in the human heart. For this reason we examined the effects of erythromycin on a rapidly activating delayed rectifier
K+ channel (Kv1.5) cloned from human heart and stably expressed in human embryonic kidney cells. When examined using the whole-cell
patch clamp technique, erythromycin (100 μM) blocked Kv1.5 current in a time-dependent manner but required prolonged exposure
to do so. However, when we examined Kv1.5 current using inside-out macropatches, erythromycin applied to the cytoplasmic surface
rapidly (within 1-2 min) inhibited Kv1.5 current with an IC50 value of 2.6 x 10-5M (1.7 - 3.9 x 10-5M, 95% C.L.). The main effect of erythromycin was to accelerate the rate of Kv1.5 current decay thereby reducing the current
at the end of a prolonged voltage-clamp pulse. Erythromycin also blocked Kv1.5 current in both a voltage- and frequency-dependent
manner but had little effect on the activation kinetics, deactivation kinetics, or the steady-state inactivation properties
of Kv1.5. These data suggest that erythromycin acts as a blocker of an activated state of the Kv1.5 channel and that it may
access its binding site from the intracellular face of the channel. This study is the first to examine the effects of erythromycin
on a cloned human cardiac K+ channel. It is concluded that erythromycin blocks Kv1.5 at clinically relevant concentrations. Blockade of voltage-dependent
K+ channels in the heart could contribute to the alterations in cardiac repolarization that have been observed with erythromycin.
Received: 22 November 1996 / Accepted: 26 February 1997 相似文献
115.
采用ELISA法检测104例各类型乙型肝炎(乙肝)患者的血清前-S2抗原(Pre-S2Ag)及其抗体(Pre-S2Ab),结果表明,Pre-S2Ag的出现与HBsAg、HBeAg、HBcAb呈显著相关性(P值均<0.005),主要见于乙肝急性期及慢性乙肝患者,说明病毒复制活跃、传染性强。而Pre-S2Ab阳性仅见于急性乙肝恢复期。 相似文献
116.
Tsuyoshi Satoh Tadashi Watanabe Masanori Tadokoro Junichi Sakamoto Hiroki Murayama Katsuki Itoh Sadayuki Sakuma Hiroshi Takagi 《Cancer science》1992,83(4):379-386
Anti-carcinoembryonic antigen monoclonal antibody (MAb) CEA102 was produced by immunization with purified CEA and the specific accumulation of radiolabeled CEA102 in colorectal cancers was investigated by autoradiography of surgical specimens using Fuji Computed Radiography (FCR). Five patients with colorectal cancer were injected intravenously with 131 I-labeled intact CEA102 or its F(ab')2 . Primary tumor and liver metastases were successfully detected by external scanning with a gamma camera in 4 cases. Autoradiographic study of the surgical specimens using FCR showed predominant localization of 131 I-labeled CEA102 in primary tumors and liver metastases in all cases. Even a small liver metastasis (0.5 cm) was clearly visualized in the autoradiogram by FCR. The pixel distribution curves of the density of the respective tissues in the autoradiograms by FCR showed the heterogeneity of the distribution of administered radiolabeled MAb in individual tumors, but the density of the tumors was higher than that of the normal tissues. In the quantitative distribution analysis of CEA102, the uptake of the primary tumor (mean 1.10%ID/kg) was ten-fold greater than that of the normal colon mucosa (mean G.10%ID/kg). These results revealed that the application of MAb has great potential in radioimmunodetection as well as in antibody-directed therapy. 相似文献
117.
A murine monoclonal antibody (MDR3M) (isotype: IgM) reactive with mdr3 gene product was generated by immunizing mice with mdr3 -specific peptide (H2 N-12 WRPTSAEGDFELGISSKQKRKKTKTVKMI41 G-COOH) and hybridizing the primed mouse splenic B cells with X63-Ag8,6.5.3 mouse plasmacytoma cells. MDR3M did not cross-react with mdr1 gene product. This monoclonal antibody may be useful for analyzing the role of mdr3 gene product in cells and tissues. 相似文献
118.
Y. W. Loke A. King T. Burrows L. Gardner M. Bowen S. Hiby S. Howlett N. Holmes D. Jacobs 《Tissue antigens》1997,50(2):135-146
A monoclonal antibody to HLA-G has been generated by immunizing HLA-A2.1/human β2 -microglobulin (β2 m) double transgenic mice with murine L cells transfected with both human β2 m and HLA-G. This monoclonal antibody, designated as G233, has been found not to cross-react with other HLA class I antigens when tested on numerous cell lines by flow cytometry. With immunohistology, all populations of extravillous trophoblast (cell columns, interstitial trophoblast, endovascular trophoblast, placental bed giant cells) were stained. An extensive range of adult and fetal tissues was also tested but none reacted with monoclonal antibody G233, including those previously reported to express HLA-G mRNA, indicating that the protein has a highly restricted distribution. Failure to detect HLA-G in the fetal thymus raises the question as to how T-cell tolerance to this antigen is induced. Immunoprecipitation of trophoblast surface proteins with monoclonal antibody G233 revealed a heavy chain of 39 kDa and a light chain of 12 kDa, indicating that HLA-G expressed on the surface of trophoblast is complexed with p2m. However, sequential immunoprecipitation with monoclonal antibody W6/32 followed by monoclonal antibody G233 continued to detect a residual band of 39 kDa, suggesting that trophoblast surface HLA-G may also occur as free heavy chains not associated with p2m. Immunoprecipitation followed by two dimensional gel electrophoresis showed that monoclonal antibody G233 recognizes several iso-forms of HLA-G from trophoblast similar to the characteristic spot array previously described for HLA-G. This monoclonal antibody G233 will be highly useful in future experiments to elucidate the function of HLA-G. 相似文献
119.
M. Kneissel P. Roschger W. Steiner D. Schamall G. Kalchhauser A. Boyde M. Teschler-Nicola 《Calcified tissue international》1997,61(2):95-100
There is abundant data on cancellous bone in the aging human spine, but little relating to the growing vertebral cancellous
bone in childhood and adolescence. The purpose of this study was to map vertebral cancellous bone in a growth and age series
of historic skeletal samples and to make comparisons with data published on recent material. Lumbar vertebral bodies were
collected from 65 skeletons (0–60 years) from a medieval Nubian population. Ethnohistoric information was collected to interpret
conditions that might have influenced bone structure and metabolism. The cancellous bone was studied three dimensionally,
using stereophotography and scanning electron microscopy and morphometrically by performing a semiautomatic structural analysis
on digitized backscattered electron images of polymethacrylate-embedded material. The cancellous bone structure in the children
consisted mainly of a densely packed, uniform network of small rodlike trabeculae. The greatest bone volume fraction with
small, more platelike trabeculae was observed during adolescence. In young adults, larger platelike trabeculae were present
in the central zone and smaller trabeculae in the superior and inferior zones, as described for modern skeletal material.
Structural changes associated with aging were observed much sooner than in modern man. By the estimated age of approximately
50–60 years, the predominant architectural elements were slender rarified rods in both sexes. The ethnohistorical data suggest
that this was essentially a black African population of physically active peasants, not likely to suffer Vitamin D insufficiency
or deficient calcium intake. Thus an earlier onset of the biological age changes in cancellous bone found in modern populations
was probably prevalent.
Received: 1 March 1996 / Accepted: 31 December 1996 相似文献
120.
KILL AND CURE THE HOPE AND REALITY OF VIRUS INACTIVATION 总被引:2,自引:0,他引:2
CHRISTOPHER PROWSE 《Vox sanguinis》1994,67(S3):191-196