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81.
The behavior of hydridonickel coordination compounds as catalysts for the oligomerization and polymerization of butadiene in various solvents was studied. In the presence of alcohol bis(tricyclohexylphosphine)chlorohydridonickel ( 4 , X = Cl) (HNiCl[P(C6H11)3]2) catalyzes the linear dimerization. With hydridotetrakis(phosphite)nickel(1+) ( 2 ) ([HNi{P(OR)3}4]+), which is prepared from tetrakis(phosphite)nickel ( 1 ) (Ni[P(OR)3]4) and trifluoroacetic acid, dimerization occurs in sec-alcohol but there is no reaction in tert-alcohol. The main product is 2-methylenevinylcyclopentane ( 8 ). The other products are 4-vinylcyclohexene ( 10 ), 1,5-cyclooctadiene ( 5 ), 1,3,7-octatriene ( 7 ) and 1,3,6-octatriene ( 9 ). The hydridonickel coordination compound, prepared with inorganic acids, does not afford the dimers but the 1,4-trans polymer.  相似文献   
82.
A case of Hodgkln's disease (HD), lymphocyte depression (LD) type In an Immunosuppressive patient is described. The patient was a 48-year-old male and his parents were born In the Kyushu area, which is an endemic area for adult T cell lymphomaheukemla (ATL). He was seropositive for ATL virus (ATLV, also referred to as HTLV-I) and showed a marked Immunosuppressive condition. He developed LD-HD and Pneumocystis carinii pneumonia, and died due to respiratory failure. The Immunohistochemical and in situ hybridization analyses revealed that the Reed-Sternberglike cells In the lymph node biopsy sample were positive for Ber-H2 (CD30), Leu-M1 (CD15), L-26 (CD20), Bcl-2, p53 and EBER, the viral genome of Epstein-Barr virus (EBV).  相似文献   
83.
We report on a 9-year-old boy with radioulnar synostosis, short stature, microcephaly, soliosis, and mental retardation. We propose that he has a new syndrome. © 1995 Wiley-Liss, Inc.  相似文献   
84.
Candidate cytomegalovirus strain for human vaccination.   总被引:15,自引:0,他引:15       下载免费PDF全文
A strain of human cytomegalovirus called Towne was isolated in WI-38 human fibrolast cell cultures from the urine of an infected infant. It was then passaged 125 times in WI-38, including three clonings, and a pool was prepared in the same cell substrate for use as a potential live attenuated vaccine. The Towne virus has a broad antigenicity and cross-reacts with the AD-169 strain. Several markers of the Towne virus were found which differentiated it from fresh isolates. One of these was resistance of the former to trypsin. The Towne virus was tested for freedom from oncogenicity or other harmful effects in preparation for tests in humans.  相似文献   
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To examine the development of T cells within an allogeneic or xenogeneic environment, we engrafted the fetal thymus from AKR mice or F344 rats under the kidney capsule of SCID mice (mTG and rTG mice). T lymphopoiesis developed in SCID mice 2 months after transplantation, although the ratio of CD4/CD8 in both experimental groups was different from that of normal control. T cells in mTG mice did not show in vitro proliferation or cytotoxicity against either host-type C.B-17 (H-2d) or donor-type AKR (H-2k) cells, while they exerted potent activities against third-party BIO (H-2b) cells. In contrast, T cells in rTG mice exhibited proliferation against both host-type C.B-17 and donor-type F344 rat cells. Consistently, graft-vs.-host disease symptoms developed in these mice and histological examination showed impressive infiltration of lymphocytes into the skin or into the mucosal layers of the stomach. Activated state of T cells in rTG mice was also evidenced by the positive expression of interleukin-2 receptor. Taken together, fetal thymus appears to contain progenitor cells which are sufficient for in vivo reconstitution of T lymphopoiesis, but species-specific environment is important for the induction of tolerance. In mTG mice, Vβ6+ T cells reactive to donor Mlsa determinants and Vβ3+ T cells reactive to host Mlsc determinants were deleted, suggesting that tolerance was regulated mainly by clonal deletion. By contrast, Vβ11+ T cells reactive to Mlsf determinants were not deleted possibly due to the lack of their ligands.  相似文献   
87.
Denervation of dopaminergic neurons by intra nigral injection of 6-hydroxydopamine (6-OHDA) increased nerve growth factor (NGF) content in the cortex and hippocampus, both of which are innervated by cholinergic neurons. The increase continued during an observation period of 0.5-28 days after the lesion. The time course of changes in NGF content was quite different from that of cholinergic neuron denervation. The decreased dopamine content produced in the striatum by 6-OHDA injection was not recovered during the observation period. These results suggest that dopaminergic neuron damage may affect NGF synthesis.  相似文献   
88.
Kawasaki disease (KD) is an acute illness of early childhood characterized by prolonged fever, diffuse mucosal inflammation, indurative oedema of the hands and feet, a polymorphous skin rash and nonsuppurative lymphadenopathy. The histopathological findings in KD comprise panvasculitis with endothelial necrosis, and the infiltration of mononuclear cells into small and medium-sized blood vessels. The levels of many proinflammatory cytokines, chemokines and adhesion molecules can be elevated in sera from children with KD at the acute stage. Although many immunological studies on KD involving peripheral blood have been reported, the data obtained remain controversial. This review focuses on the immune response of peripheral blood lymphocytes and monocytes/macrophages during acute KD.  相似文献   
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