肝内HBcAg与血清学指标的关系及慢性乙型肝炎发病机理的探讨

We detected the presence and distribution of HBcAg in the liver by immunohistochemistry (ABC method) and the presence of HBV-DNA in serum (spot hybridization) and anti-HBe in serum (ELISA) from 59 cases of hepatitis B hospitalized in our hospital, including 47 cases of CAH, 5 cases of CPH, and 7 cases of subacute fulminant hepatitis. 1. HBcAg in the liver was detected in 25 out of 47 cases (53%) of CAH, in 2 out of 5 cases of CPH and in 4 out of 7 cases of subacute fulminant hepatitis. The total percentage was 53% (31/59). 2. There was no positive correlation between HBV replication activity and liver disease activity (P greater than 0.05). Our results did not support the hypothesis that suggests a direct cytopathic effect of HBV. Oppositely, the fact was that the presence, the amount and the patterns of HBcAg in the liver, and the presence of HBV-DNA in serum were predominant in mild CAH compared with those in severe CAH, predominant in CAH without cirrhosis compared with those in CAH with cirrhosis. There was a tendency of inverse correlation between HBV replication activity and liver disease activity. The results above were in line with the concept that HBcAg expressed on the surface of infected hepatocytes may be relevant target for T lymphocyte cytotoxicity. The results have suggested that an immune response to HBV is present, leading to the destruction of most infected cells. 3. There was a positive correlation between HBV-DNA in serum and HBcAg in the liver (P less than 0.005), indicating that HBV-DNA in serum can represent HBV replication.(ABSTRACT TRUNCATED AT 250 WORDS)     

Differential protective effects of varying degrees of hypoxia on the cytotoxicities of etoposide and bleomycin

Summary Oxygen is thought to be involved both directly and indirectly in the mechanisms of action of several anticancer agents. We studied the effects of various oxygen concentrations on the cytotoxicities of the following drugs: bleomycin (BLM), etoposide (VP-16), doxorubicin (DOX), and mitomycin C (MMC). Human sarcoma cells, MESSA, were exposed to drug for 1 h at one of several oxygen concentrations: less than 1%, 2.5%, 5%, 21%, and 95%. Cytotoxicity was assessed by cellular incorporation of ³H-thymidine into DNA 5 days after drug exposure. Control experiments varying oxygen concentration without drugs demonstrated toxicity only at the highest concentration (95%). Three different responses of drug sensitivity to varying oxygen tensions were observed. BLM, which has been shown to utilize oxygen as a substrate in generating free radicals and producing DNA scission, demonstrated a progressive increase in cytotoxicity over the entire range of increasing oxygen concentrations. This is consistent with the model of a BLM-cation-oxygen complex and catalytic reduction of oxygen. VP-16, which also produces DNA strand breakage but by interaction with topoisomerase II, exhibited a threshold response. VP-16 toxicity was ameliorated by anoxic conditions (less than 1% O₂), but not by oxygen concentrations of 2.5%–95%. The reason for this protective effect of anoxia with VP-16 is not clear. In contrast, acute anoxia had no effect on the cytotoxicities of DOX and MMC. We conclude that acute hypoxia protects cells from both BLM and VP-16 but that the nature of that protection is different. VP-16 toxicitiy is blunted only by severe anoxia, wheaeas BLM exhibits a dose response effect over the entire range of oxygen concentrations.Supported by NIH grant CA-27478 from the US Department of Health and Human Services, and by the American Lung Association. Dr. Sikic is a recipient of a Faculty Development Award in Clinical Pharmacology from the Pharmaceutical Manufacturer's Association Foundation.     

冰点下降法测定血、尿渗透压的临床应用及注意事项

本文应用溶液冰点下降法测定了178例正常血清渗透压。结果为287±13毫渗量/kg水。并对20例尿崩症病人在限水加压素试验过程中测定血清,尿渗透压。尿崩症病人尿渗透压明显低于正常人。注射加压素后,尿渗透压升到正常。在多尿症的鉴别诊断中,此法是一种简便,灵敏的手段。有重要的诊断价值。     

来流温度不均匀对叉流换热器性能的影响

对来流温度不均匀叉流换热器,本文进行了熵产生和(火用)效率的数值分析。结果表明:①在相同的传热单元数和热容量比值下,对应于换热效果最好的来流温度分布,其熵产生单元数最小,(火用)效率最高。②在给定的条件下,换热器的(火用)效率并不是随传热单元数的增加而单调增加,而是存在一个极大值,它所对应的传热单元数要小于有效度ε_(max)对应的传热单元数。③熵产生单元数也并不是随传热单元数的增加而单调减少,而是有时单调增加,有时有极大值。并对以上现象作了一些物理机理的分析和讨论。     

抗人甲状腺球蛋白单克隆抗体的制备及其对抗原决定簇特异性的研究

用杂交瘤技术建立三株分泌抗甲状腺球蛋白(TG)单克隆抗体的杂交瘤细胞株。所获三种单克隆抗体经兔抗小鼠IgG亚类、IgM及IgA血清鉴定表明,两种为IgG_1,一种为IgA;三种含单克隆抗体小鼠腹水的滴度(ELISA法)均为51200以上;以竞争性固相抗体结合试验测定它们对抗原决定簇的特异性差异,结果发现三种单克隆抗体的抗原结合部位是不同的,但对抗原的结合有一定的相互竞争抑制现象。     

RESEARCH ON A REAL-TIME CONTROL SYSTEM OF LOW POWER DISSIPATION FOR CONTINUOUS CYCLIC PERITONEAL DIALYSIS(CCPD) CYCLER

FOREWORDPeritonealdialysisrepresentssoluteandfluidexchangemainlybetweenperitonealcapillarybloodanddialysissolutionintheperitonealcavity'CombinedwithhemodialySisandrenaltransplantation,peritonealdialysisisusedmainlyforthetreatmentofrenalfailure,particularlyforchronicfailure'In1976,Prof'Popovichdevelopedcontinuousambulatoryperitonealdialysis(CAPD)basingontheconceptofcontinuousequilibrationdialysis('1'Fromthenon,peritonealdialysisfounditsclinicaluse'Continuouscyclicperitonealdialysis(CCPD…     

心血管外科术后急性肾功能衰竭的处理

目的：总结两组心血管外科术后急性肾功能衰竭病例的治疗经验，提出心血管外科术后急性肾功能衰竭的特点、早期诊断标准及处理原则。方法：１７例心血管外科术后急性肾功能衰竭病例，以入院先后分为两组。第１组８例，第２组９例。回顾第１组病例的急性肾功能衰竭的治疗经验，总结腹膜透析、血液透析和血液滤过的优缺点。在第２组病例治疗中，以急性肾功能衰竭的早期诊断为前题，早期开始腹膜透析。同时，强调综合治疗的重要性。结果：第１组病例均死亡。第２组病例，７例存活（７８％）。结论：心血管外科术后急性肾功能衰竭的早期诊断和早期肾功能替代疗法，是治疗成败的关键。腹膜透析简便易行，在急性肾功能衰竭的早期开始腹膜透析，可以收到良好效果，并以此作为心血管外科术后急性肾功能衰竭的首选肾功能替代疗法。     

不同浓度氢氟酸对大鼠血钙变化的影响

OBJECTIVE: To evaluate the effects of different concentration of hydrofluoric acid (HF) on local skin and calcium level of serum. METHODS: SD rats were divided into two groups which were wounded by 20% and 40% percent of HF respectively. Samples of blood and wound tissue were harvested at different postburn time for the analysis of the calcium level of the serum and histological study. RESULTS: It was found that twenty percent of HF was enough to cause a skin damage, and might bring about fatal hypocalcemia after a prolonged contact. High concentration of HF (40%) could cause deep tissue necrosis within a short time, and result in a fatal hypocalcemia within 24 hour even in the case of a small area injury. CONCLUSION: It is important to treat the patient with HF injury as early as possible. Sufficient calcium must be applied guided by laboratory study in order to prevent the fatal hypocalcemia.     

Stress signaling through Ca2+/calmodulin-dependent protein phosphatase calcineurin mediates salt adaptation in plants

Calcineurin (CaN) is a Ca²⁺- and calmodulin-dependent protein phosphatase (PP2B) that, in yeast, is an integral intermediate of a salt-stress signal transduction pathway that effects NaCl tolerance through the regulation of Na⁺ influx and efflux. A truncated form of the catalytic subunit and the regulatory subunit of yeast CaN were coexpressed in transgenic tobacco plants to reconstitute a constitutively activated phosphatase in vivo. Several different transgenic lines that expressed activated CaN also exhibited substantial NaCl tolerance, and this trait was linked to the genetic inheritance of the CaN transgenes. Enhanced capacity of plants expressing CaN to survive NaCl shock was similar when evaluation was conducted on seedlings in tissue culture raft vessels or plants in hydroponic culture that were transpiring actively. Root growth was less perturbed than shoot growth by NaCl in plants expressing CaN. Also, NaCl stress survival of control shoots was enhanced substantially when grafted onto roots of plants expressing CaN, further implicating a significant function of the phosphatase in the preservation of root integrity during salt shock. Together, these results indicate that in plants, like in yeast, a Ca²⁺- and calmodulin-dependent CaN signal pathway regulates determinants of salt tolerance required for stress adaptation. Furthermore, modulation of this pathway by expression of an activated regulatory intermediate substantially enhanced salt tolerance.