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Volume ， Issue 4 ， 1996
- Abstract：The primary Syrian hamster embryo（SHE） cells were used to study the oncogenic transformation by ￣（238）pu α particles or X-rays alone or in combination with a chemical promoter phorbol ester.Survival curves of SHE cells following exposure to α-particles or X-rays were fitted to single-or multi-target models,respectively. Model parameters were: Do = 0. 55 Gy. n = 1 for α particles 4 Do = 1.44 Gy. Dq = 3.0 Gy. n=7.7 for X-rays.Incidence of α particles or X-rays induced cell transformation was dose-dependant.α particles were more efficient in inducing cell transformation than that of X-rays. The enhancement of SHE cell transformation by phorbol 12-myristate 13-acetate（PMA） following exposure to α particles of 0. 25-1. 00 Gy was observed.4|3|0Updated：2024-04-10
- Abstract：Breast tumorigenesis proceeds through an accumulation of specific genetic alteration. Breast malignant transformation is dependent on not only the rate of cell production but also on apoptosis,a genetically programed process of autonomous cell death. We investigated whether breast tumorigenesis involved an altered susceptibility to apoptosis and proliferation by examining normal breast epithelium and breast cancer samples. We found there is a great inhibition of spontaneous apoptosis in breast cancer cells compared with normal breast epithelium. The inhibition of apoptosis in breast cancer may contribute to neoplastic transformation.4|22|1Updated：2024-04-10
- Abstract：A novel strategy to enhance the expression efficiency of cloned target gene in Escherichia coli was developed. The whole expression cartridge , consisting of promoter. SD sequence , target gene and transcription terminator, was tandem repeatedly engineered into a expression plasmid. Consequently, the copy number of specific gene was increased substantially, leading to the improvement of expression efficiency.Using this approach, a recombinant plasmid , designed as PLYD, was constructed and transformated into the Escherichia coli strain DH5α. Upon induction , the desired protein was synthesized in a considerable level and accumulated up to 63% of the total cell proteins. The present study revealed that tandem repeating of expression cartridge provided a convenient means to improve expression level efficiently.4|8|0Updated：2024-04-10
- Abstract：ＥｖａｌｕａｔｉｏｎｏｎｔｈｅＤｅｔｅｃｔｉｏｎｏｆＭｙｃｏｂａｃｔｅｒｉｕｍＴｕｂｅｒｃｕｌｏｓｉｓｉｎＣｌｉｎｉｃａｌＳａｍｐｌｅｓｂｙＰＣＲａｎｄＤＮＡＰｒｏｂｅＷｕＸｕｅｑｉｏｎｇ（吴雪琼）；ＺｈｕａｎｇＹｕｈｕｉ（庄玉辉）；ＺｈａｎｇＸｉａ...4|8|0Updated：2024-04-10
- Abstract：TGF-β is a multifunctional cytokine that regulates many aspects of cellular function, including periosteal mesenchymal cell proliferation, differentiation. This experiment is to study its effects on bone defect repair. A rabbit radial bone defect model was used to evaluate the effect of TGF-β, which was extracted and purified from bovine blood platelets, on the healing of a large segmental osteoperiosteal defect. A 1. 5-centimeter segmental defect was created in the mid-upper part of the radial shaft of adult rabbits. The defect was filled with implant containing TGF-β that consisted of carrier and bovine TGF-β. Limbs served as controls received carrier alone. The defectswere examined radiographically and histologically at 4, 8,12 , 16 and 20 weeks after implantation. The results showed that in TGF-β implant group . the defect areas at 12 weeks post operation were bridged by uniform new bone and the cut ends of cortex could not be seen;while in control group, the defects remained clear. Only a small amount of new bone formed as a cap on the cut bone ends. In the experimental group, new lamellar and woven bone formed in continuity with the cut ends of the cortex. An early medullar canal appears to be forming and contained normal-appearancing marrow elements; while the control group displayed entirely fibrous tissue within the defect site. Remnants of the cancellous bone carrier were observed in the control specimen. These data demonstrate that exogenous TGF-β initiate osteogenesis and stimulate the bone defects repair in animal model.4|8|4Updated：2024-04-10
- Abstract：To study the role of Ca2+ in the pathogenesis of pituitary growth hormone secreting adenomas, the function of Ca2+ in 23 cases of human Prturtary GH-secreting adenoma was investigated in monolayer cell culture. It was found that Ca2+ channel blockers nicardipin and nifedipin inhibrted basal and growth hormone releasing hormone （GRH）stimulated GH secretion in 87. 5 % and 100. 0 % of the GH adenomas . respectively, demonstrating that in most human pituitary GH adenomas, the basal and GRH regulated GH secretion is Ca2+ dependent. The GRH and sometostatin （SRIF） agonist octreotide regulated the processes of GH secretion via Ca2+ had defects in different steps including receptor ,postreceptor Ca2+ channel and Ca2+GH secreting coupling in 6 （66. 6%） and 5 （55. 5 % ） cases of 9 GH adenomas respectively. Among them,the defects in GRH receptor and SRIF regulated Ca2+ channel are the main causes of the dysfunction of GH adenomas. These defects may be related to GH hypersecretion in GH adenomas. Our data provides advance evidences for intrinsic defects of GH adenomas.4|9|0Updated：2024-04-10
- Abstract：ＡｇｇｒａｖａｔｉｏｎｏｆＣａｌｃｉｕｍＣｈａｎｎｅｌＡｃｔｉｖｒｔｉｅｓｂｙＯｘｙｇｅｎＦｒｅｅＲａｄｉｃａｌｉｎＲａｔＣａｒｄｉｏｍｙｏｃｙｔｅｓＢａｏＧｕａｎｇｈｏｎｇ（鲍光宏）；ＬｉｕＤｏｎｇｍｅｉ（刘东梅）ａｎｄＹｕＤｅｊｉｅ（于德洁）(Ｉ...4|4|0Updated：2024-04-10
- Abstract：To investigate the correlation between sarcoidosis and Borrelia burgdorferi （Bb ） infection , flagella DNA of Bb were detected in 23 granulomatous tissue specimens from patients with confirmed sarcoidosis using polymerase chain reaction in siju technique （in situ PCR） and the antibodies to Bb were examined in 55 serum samples obtained from the patients by indirect immunoflurescence assays. Our data presented that:（1） None of granulomatous tissues was found to have Bb DNA in 23 tissue samples. （2） Thirty of 55 （54. 6% ） patients with sarcoidosis were found antibodies to Bb positive ,in contrast ,six of 60 （10%） normal subjects had antibodies against Bb ,the positive rate was remarkably higher in patient group than that in healthy group （P<0. 005） . The results suggest that Bb might not be the causative agent of sarcoidosis.the elevated titres of serum antibodies against Bb in patients with sarcoidosis is a nonspecific response.4|14|1Updated：2024-04-10
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EFFECT OF HYPOXIA ON DNA SYNTHESIS AND C-MYC GENE EXPRESSION OF PULMONARY ARTERY SMOOTH MUSCLE CELLS
Abstract：The neonate is particularly susceptible to the development of hypoxic pulmonary hypertension. The present study was undertaken to observe the effect of hypoxia on DNA synthesis and c-myc gene expression between newborn calf and adult bovine PASMC in vilro. DNA synthesis measured by 3H- TdR incorporation was increased after hypoxic challenge for 24h. Hypoxia enhanced the increment in 3H-TdR incorporation induced by EGF. Northern blot analysis revealed that PASMC cultured in both normoxia and hypoxia expressed c- myc gene transcript of 2. 2Kb ,but there is a higher 2. 2Kb mRNA expression in hypoxic PASMC than that in normoxia. We speculate that newborn calf PASMC exhibited potential response to hypoxia than adult,which was augmented by EGF. Enhanced c-myc gene expression may lead to a great understanding of the mechanism of PASMC growth in the development of pulmonary hypertension.4|3|1Updated：2024-04-10 - Abstract：Objective. The experiment was designed to study the association of cerebral ischemia and reperfusion with endothelin- 1 （ET- 1） gene expression of rat brains and time-dependent changes of ET- 1 gene expression during cerebral ischemia.Materials and methods. Thirty- three male SD rats were divided into dot blot hybridization（n = 27） and in silu hybridization groups（n= 6）. The focal cerebral ischemia and reperfusion models were made with suture embolism of middle cerebral artery. Dot blot hybridization groups were redivided into control and ischemic subgroups （ischemia for 0. 5 , 1 , 1. 5 , 3 , 6 , 12 , 24 , 48 and 72 h respectively）. In situ hybridization groups were redivided into ischemia and reperfusion groups. After 24 h ischemia and 24 h reperfusion,ET1 gene expressions were investigated with in situ hybridization and the resuhs were analyzed with IBAS 2000 Image Analysis System.Results. Dot blot hybridization showed that ET-1 mRNA of cerebral cortex and caudate- putamen was increased at 6 h of ischemia and reached peak at 24 h （3. 9 and 3. 7 fold respectively） ,and at 72 h of ischemia it remained at high levels（3. 5 and 2. 1 fold respectively）. In silu hybridization showed that the levels of ET- 1 mRNA of cerebral cortex and caudate-putamen were also markedly increased both in 24 h ischemia and 24 h reperfusion groups （P<0. 01 , P<0. 05 respectively） .Conclusions. ET-1 gene expression in focal ischemic brain tissue were markedly and progressively increased during cerebral ischemia and reperfusion and downregulation of ET- 1 gene expression may be a new approach to the treatment of ischemic cerebrovascular diseases.4|8|8Updated：2024-04-10
- Abstract：Objective. To explore the role of HLA- DRBI genes in the development of rheumatoid arthritis（RA） and the orrelations between HLA-DR alleles and clinical manifestations of patients with RA.Methods. 86 patients with rheumatoid arthritis and 106 race matched controls were studied in whom HLA-DR typing was perfomed by the method of DNA amplification with sequence-specific primers（PCR-SSP）. The subtypes of HLA- DR4 were determined by the method of hybridization of PCR products with sequence- specific oligonucletides（PCR-SSO） . The absence or presence of HLA-DR4 and its subtypes was correlated with the clinical and serological characteristics of the patients.Results. Compared with controls, an increased gene frequency of HLA-DR4 （48. 8% vs 17. 9 % , P<0. 001） and a decreased frequency of HLADR7 （ 16. 3% vs 27. 4 % , P = 0. 06 ） were found. The DRB1.0405 account for 61. 9 % of DR4+RA patients and 21. 1% of DR4+ controls（P<0. 01 ）. There was no difference between the DR4+ and DR4- patients with respect to age ,sex ,duration of disease ,rheumatoid factor （RF） ,extra-articular manifestations including secondary Sjogren’ s syndrome. According to the wrist X- ray stage,the patients of DR4+ were more severe than that of DR4- （P<0. 05）.Conclusicon. HLA-DR4 and DR4 subtype of DRB1 0405 are related to the development of RA in Chinese. HLA-DR4 can be a useful prognostic marker in the patients with RA.4|13|1Updated：2024-04-10
- Abstract：The aim of this study is to test the patency rate and safety of the accelerated streptokinase dose regimen for coronary thrombolysis compared with the conventional one. One hundred and four patients enterring three hospitals up to 12 hours after the onset of definite acute myocardial infarction were randomizely treated with intravenous accelerated streptokinase dose regimen （ 1. 5 million units/30 min） （group A, 47 cases） and conventional dose regimen （ 1. 5 million units/60 min） （group B , 57 casese）. The reperfusion rate of infarct-related arteries determined by clinical evidence of reperfusion was 76. 6% （36/47） in group A VS 61. 4% （35/57） in group B. There was significant difference in reperfusion rates among patients within 6 hours after the onset of chest pain : 87. 9% （29/33） in group A VS 67. 4 （29/43） in group B（P<0. 05 ）. The incidence of mild bleeding , allergic reaction , hypotension was 12. 8 % （ 6/47 ） , 4. 3 % （ 2/47 ） , 12. 8 （ 6/47 ） respectively in group A vs 21. 1 （ 12/57 ） , 3. 5 （2/57） . 17. 5 % （ 10/57） respectively in group B. Compared to conventional dose regimen, intravenous accelerated streptokinase dose regimen for coronary thrombolysis seems to improve reperfusion rate markedly without increasing adverse events such as bleeding , allergic reaction and hypotension. It suggests that accelerated streptokinase therapy deserves more extensive investigation.4|6|0Updated：2024-04-10
- Abstract：The efficacy of right atrial-pulmonary artery （RA-PA） bypass during acute right ventricular failure （RVF） produced by pulmonary artery constriction in dogs was examined in this study Control group （n=7） was supported with conventional volume loading and inotropic therapy. In the experimental animals （n=8） , RA-PA bypass was initiated 5 min. after the onset of severe RVF. Three control animals died from refractory ventricular fibrillation within one hour of RVF. No animals in the experimental group died within two hours of RA-PA bypass , but the histological study of the lungs in these animals demonstrated peribronchial , perivascular and intraalveolar hemorrhage. Light microscopic and electron microscopic examination of the myocardial specimens of the right ventricular free wall displayed the myocardial structures and ultrastructures were maintained effectively with RA-PA bypass while irreversible myocardial injuries occurred in the control animals after two hours of RVF with conventional therapy. During the 2 hours of RA-PA bypass, the hemodynamic indices were also maintained better when compared to the control animals. It may be concluded , a roller pump right ventricular assist device effectively unloads the acute failing right ventricle, maintains systemic cardiac output , and significantly reverses the myocardial ischemia during right ventricular failure, but RA-PA bypass may induce pulmonary hypertension due to increased pulmonary vascular resistance secondary to pulmonary edema and interstitial hemorrhage.4|4|2Updated：2024-04-10
- Abstract：Enzyme-linked colorimetric analysis and adioimmunoassay were employed to detect serum fasting total bile acids（FBA） and choloyglycin （CG） respectively in cases of 32 neonatal hepatitis , 33 cases of neonatal unconjugated hyperbilirubinemia and 34 cases of breast milk jaundice（BMJ）. FBA and CG in acute period of neonatal hepatitis were obviously elevated and decreased gradually in convalescent and recovered period. The difference was significant for each stage as compared with controls. Acute FBA correlated strongly with the course. Both neonatal unconjugated hyperbilirubinemia and BMJ differed significantly from controls in FBA and CG. The results suggested that serum FBA and CG were helpful in Judging the course and state of neonatal hepatitis, and cholestasis might existed in neonatal unconjugated hyperbilirubinemia.4|9|0Updated：2024-04-10
- Abstract：In order to understand the effect of surgery in the treatment of the bronchial carcinoid tumor and the factors affecting prognosis, 18 cases of bronchial carcinoid tumor are presented, including 5 cases with Cushing’s syndrome. There were lobectomy in 10, lung wedge resection in 3, excision of intraluminal tumor of bronchus in 3, exploratory thoracotomy in 2 cases. No operation death. Pathological examination revealed 14 cases were typical carcinoid tumor and 4 cases were atypical carcinoid tumor. By 2-13 years follow-up . 3 , 5 and 10 years survival rate were 82% , 78%and 70% respectively. Bronchial carcinoid tumor is often confused with small cell carcinoma of lung, the correct diagnosis can be obtained by light microscopic, electron microscopic and immunohistochemistry studies. Those patients accompanied with ectopic-ACTH secretion always have Cushing,s syndrome , resection of tumor can produce gho result. Proper operation method depends on the location of the tumor and patient’s extent of cardiac and pulmonary reserve.Atypical carcinoid tumor had high malignancy and poor prognosis. The size of tumor, lymph node involvement and adjuvant therapy seem no definite effect on the patients’ survival rate.4|14|2Updated：2024-04-10
- Abstract：This paper surnmarizes the historical experiences in venereal disease control in China during the 1950s.Venereal diseases had been all but eliminated in the whole country till 1964. However, along with the implementation of open-door policy and economic reform in the 1980s, the social environment was changed to a great extent in this country. Sexually transmitted diseases （STDs） were reintreduced in the Chinese mainland and new foci of infection established themselves in some cities. During the recent 8 years the national STD case-reporting and sentinel surveillance systems have been set up. The results of surveillance show that the annual incidence of STD has been on the increase. The existing factors associated with the increasing incidence of STD mainly are ; population movement , increasing affiuence in a part of population,the availability of multiple sexual partners （including the prostitution）and asymptomatic STD increased.Finally, the strategies for STD control are discussed in detail.4|34|7Updated：2024-04-10
- Abstract：ＳＵＢＪＥＣＴＩＮＤＥＸＣＨＩＮＥＳＥＭＥＤＩＣＡＬＳＣＩＥＮＣＥＳＪＯＵＲＮＡＬＶｏｌｕｍｅ１１，１９９６Ａｄｅｎｙｌａｔｅｃｙｃｌａｓｅ（ＡＣ）ＥｆｆｅｃｔｓｏｆＤｙｎｏｒｐｈｉｎＡ（１－１７）ｏｎＭｏｔｏｒＦｕｎｃｔｉｏｎａｎｄＳｐｉｎａｌＩｎ...4|3|0Updated：2024-04-10
- Abstract：ＣｏｒｏｎａｒｙＦｌｏｗＲｅｓｅｒｖｅｉｎＰａｔｉｅｎｔｗｉｔｈＥｓｓｅｎｔｉａｌＨｙｐｅｒｔｅｎｓｉｏｎａｎｄＬｅｆｔＶｅｎｔｒｉｃｕｌａｒＨｙｐｅｒｔｒｏｐｈｙＣａｉＸｕ（蔡煦）；ＳｈｅｎＷｅｉｆｅｎｇ（沈卫峰）；ＺｈａｎｇＤａｄｏｎｇ（张大东）...4|4|0Updated：2024-04-10
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