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81.
This study demonstrates that ZnSO4 induced chemical trauma results in an in situ regeneration of the olfactory epithelium which, when maintained in vitro, provides an enriched population of olfactory neurons. Therefore, the ability of the olfactory epithelium to respond to chemical trauma with increased mitotic activity can be used to increase growth of neurons in culture. Tissue obtained from normal or vehicle-treated adult mice produced few olfactory neurons, when maintained in culture, compared to cultures established from tissue following an in situ ZnSO4 trauma. Maximal neuronal yields were obtained in cultures established from tissue that was removed 4–6 days following chemical trauma. The morphological appearance and the presence of cell specific intermediate filament proteins were used to classify the cell types in these olfactory epithelial cultures. Single cells and aggregates of cells which were immunopositive for keratin, but immunonegative for neurofilament protein and GFAP, were identified as epithelioid. Flattened polygonal cells immunopositive for GFAP were identified as glia. A small population of flattened cells was immunonegative for all of the antibodies used in this study. Cells that had processes were immunonegative for GFAP and keratin. Some were immunopositive for 200 kDa and 160 kDa neurofilament proteins but immunonegative for the 68 kDa neurofilament protein. A few of these cells showed positive immunoreactivity with the olfactory marker protein (OMP) antibody and most likely represented the most mature olfactory neurons in the cultures. This trauma-induced culture model using olfactory tissue from adult mice can serve as a source of CNS neurons for comparison with cultured embryonic neurons. 相似文献
82.
观察了黄芪注射液对流行性出血热病毒(EHF.V)的抑制作用。动物及传代细胞实验结果显示:黄芪注射液对小白鼠乳鼠体内EHF.V的感染过程具有一定的阻断作用;其机制可能主要是通过宿主的免疫调节而发挥作用。 相似文献
83.
本文应用改良的血浆凝块技术和共培养系统研究特发性血小板减少性紫癜(ITP)患者T细胞在体外对异体骨髓巨核细胞生成作用的影响,以探讨ITP的发病机制。实验结果表明,从总体来看,ITP患者的T细胞当加到培养物中和靶细胞共培养时,对巨核系祖细胞集落形成单位(CFU-MK)的集落效应无明显的影响。其中三例PAIgG升高患者的T细胞对CFU-MK有不同程度的抑制作用。以上结果提示ITP的发病机制相当复杂。除体液免疫机制外,也有细胞免疫机制参与,T细胞或其亚群对巨核系祖细胞生成抑制在ITP的发病机制中可能起着一定的作用。 相似文献
84.
Kohei Hara MD PhD Shigeru Kohno MD PhD Hironobu Koga MD PhD 《Journal of infection and chemotherapy》1996,1(3):166-176
Conclusion Reviewing the history of diagnostic procedures of causative organisms of respiratory infections, invasive techniques such
as the protected specimen catheter (PSB) and bronchoalveolar lavage (BAL) have become the preferred choices because they have
many advantages. These methods cause the patient relatively little discomfort, and permit an early diagnosis since they can
easily be performed at the bedside and the causative organism from the disease site is obtained in cultures. These procedures
can be used not only in patients with community-acquired lung infections, but also in immunocompromised hosts, including those
with blood diseases or following renal transplantation, in patients in intensive care units and in mechanically-ventilated
patients so that the cause can be accurately determined and chemotherapy started quickly, resulting in better therapeutic
efficacy.
Although these invasive procedures are advantageous for the diagnosis of respiratory infections, they also present various
problems which remain to be addressed including minimizing contamination and setting diagnostic threshold values. However,
the importance of accurately determining the causative organism in respiratory infections should be recognized as the most
important factor, and these methods have shown to date to provide the most accurate information to aid in the timely treatment
of respiratory infections in a wide variety of patients. 相似文献
85.
The epithelial cells of the colonic mucosa of the animal have proved impossible to culture using standard tissue culture techniques. Immortalization of adult colonic epithelial cells has been unsuccessful due to the lack of DNA synthesis in these cells once they are isolated from the tissue. Recently an unique transgenic mouse bearing a temperature sensitive mutant of the known immortalizing gene, SV40 large T has become available. The advantage of this mouse is that the SV40 large T gene is expressed in every cell. Active immortalizing protein is produced in each cell at the permissive temperature. We have used colonic mucosa from these mice to initiate cultures of epithelial cells from the colon of adult mice. The cells grow readily at the permissive temperature but die within 7 days at the non-permissive temperature. The methods used to develop these cultures are described. 相似文献
86.
黄鹤群 《南通大学学报(哲学社会科学版)》2002,18(3):105-109
江海文化既有长江流域的源远流长 ,又有沿海岸线文化的博大精深 ,其构成源自水流文化的浸润、南北文化的影响、移民文化的交流、战地文化的积淀、艰苦创业的铸炼。文化是一个民族的根系 ,是一个民族的“身份证”。加强江海文化建设 ,把南通市建成文化大市 ,是我市新形势下的重要任务。为此 ,须理清江海文化建设的思路 ,找准切入点和突破口 ,在文化大市建设中显示文化投入的大气 ,展现独具特色的“灵气” ,焕发社会发展进步的朝气 ,奠定长期发展的底气。 相似文献
87.
Homologous testis transplantation in dogs 总被引:4,自引:0,他引:4
Evert J. Barten Hayrabet Garybian Pieter J. Klopper Donald W. W. Newling 《Transplant international》1997,10(5):362-368
There is growing interest in the possible use of homologous testis transplantation for the treatment of anorchia and male
infertility. In order to test the surgical and immunological feasibility of this therapy, three series of experimental studies
of homologous testis transplantation were carried out in dogs. In the first pilot study, four beagles from the same litter
were transplanted using microsurgical techniques for end-to-end anastomosis of the testicular vessels and the vas deferens.
These dogs received cyclosporin A (CyA) for 3 months after transplantation. The longest functional graft survival in this
series was 163 days, strongly suggesting that long-term survival of a homologously transplanted testis graft is possible.
A second series of operations was performed on ten mongrel dogs. The same surgical technique was employed and the series was
divided into three groups.
Group 1 received CyA monotherapy, group 2 a combination of CyA and prednisolone, and group 3 received no immunosuppression.
The average graft survival time in this series was 18 days, significantly less than the 71 days in the first series. The dogs
in group 2, however, had graft survival times that were three times longer than those in the other two groups, suggesting
that CyA in combination with prednisolone yields the best graft survival. In the third series, five littermates received a
testis graft after castration. Immunosuppression was achieved by administration of CyA and prednisolone for 3 months. In three
out of five animals, the graft survived until the immunosuppressive therapy was suspended. Histological biopsies of the graft
3 months after transplantation showed the same maturation of sperm cells as in the control testis of the same dog. The results
of the last series suggest that long-term survival of homologously transplanted testis grafts in dogs is, indeed, possible
with the aid of CyA and prednisolone.
Received: 14 August 1996 Received after revision: 21 March 1997 Accepted: 24 April 1997 相似文献
88.
蜂王浆冻干粉对小鼠肿瘤的抑制作用 总被引:4,自引:0,他引:4
目的研究蜂王浆冻干粉对小鼠肿瘤的抑制作用.方法按每公斤体重0g、0.25g、0.50g、0.75g设对照及低、中、高3个剂量组,经口给予蜂王浆冻干粉30d后,接种小鼠肉瘤180(S180)和艾氏癌腹水型(EAC)两个瘤种.结果在两次重复的小鼠S180和EAC抑瘤试验中发现中剂量组瘤重明显低于阴性对照组(P<0.05),抑制率可达34%;中剂量组荷瘤小鼠平均生存时间均明显高于对照组(P<0.05).结论蜂王浆冻干粉具有抑制肿瘤的作用. 相似文献
89.
利用人类骨髓粒一单核系祖细胞集落(CFU—GM)和成纤维细胞集落(CFU—F)体外检测技术,比较观察32例骨髓增生异常综合征(MDS)和11例慢性原因不明性粒细胞减少症(CIN)患者的造血改变。结果表明,MDS 和 CIN 的造血状态存在显著区别,69%的 MDS 患者 CFU—GM集落显著受抑,集簇、簇/落比值明显升高;其 CFU—F 集落亦存在明显缺陷。而 CIN 患者的上述指标均类似于正常。这提示体外集落检测技术有助于 MDS 和 CIN 的鉴别。此外,CFU—GM 系列培养对 MDS 患者具有一定预后价直。 相似文献
90.
Michiko Oka Y. Itoh Shigeru Tatsumi F.-H. Ma Yojiro Ukai Yoshiaki Yoshikuni Kiyoshi Kimura 《Naunyn-Schmiedeberg's archives of pharmacology》1997,356(2):189-196
The effect of (+)-5-oxo-D-prolinepiperidinamide monohydrate (NS-105), a novel cognition enhancer, on adenylate cyclase activity
was investigated in cultured neurons of the mouse cerebral cortex. NS-105 (10–7 and 10–6 M) inhibited forskolin-stimulated cyclic AMP formation, an action that was dependent on pertussis toxin-sensitive G proteins.
Conversely, in pertussis toxin-pretreated neurons, NS-105 (10–7 –10–5 M) significantly enhanced the forskolin-stimulated cyclic AMP formation, and this action was completely reversed by cholera
toxin. A metabotropic glutamate receptor agonist (1S, 3R)-1-aminocyclopentane-1, 3-dicarboxylic acid (1S, 3R-ACPD) produced
similar bi-directional actions on the cyclic AMP formation. Both of these inhibitory and facilitatory actions of NS-105 and
1S, 3R-ACPD were blocked by L(+)-2-amino-3-phosphopropinoic acid (L-AP3). NS-105 (10–6 M) and 1S, 3R-ACPD (10–4 M) significantly enhanced isoproterenol- and adenosine-stimulated cyclic AMP formation. The enhancement of such Gs-coupled
receptor agonists-stimulated cyclic AMP formation was also produced by quisqualate but not by L(+)-2-amino-4-phosphonobutanoate
(L-AP4). The phosphoinositides hydrolysis was enhanced by 1S, 3R-ACPD (10–4 M) but not by NS-105 (10–6 M), however, 1S, 3R-ACPD-induced increase in phosphoinositides turnover was attenuated by NS-105. These findings suggest
that NS-105 stimulates metabotropic glutamate receptor subclasses that are coupled both negatively and positively to adenylate
cyclase, but it acts as an antagonist at the receptor subclasses that are linked to phosphoinositides hydrolysis.
Received: 3 February 1997 / Accepted: 25 April 1997 相似文献