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1.
Bi-Hua BIE Yong CHEN Zhi-Qi ZHAO Institute of Neurobiology Fu-Dan University Shanghai China Institute of Shanghai Physiology Chinese Academy of Sciences Shanghai China 《中国神经科学杂志》2006,(2)
Objective Ligustrazine, also named as tetramethylpyrazine, is a compound purified from Ligusticum chuanxiong hort and has ever been testified to be a calcium antagonist. The present investigation was to determine the antinoci-ceptive effect of ligustrazine and, if any, the peripheral ionic mechanism involved. Methods Paw withdrawal Latency ( PWL) to noxious heating was measured in vivo and whole-cell patch recording was performed on small dorsal root ganglion (DRG) neurons. Results Intraplantar injection of ligustrazine (0.5 mg in 25μl) significantly prolonged the withdrawal latency of ipsilateral hindpaw to noxious heating in the rat. Ligustrazine not only reversibly inhibited high-voltage gated calcium current of dorsal root ganglion (DRG) neuron in dose-dependent manner with IC50 of 1.89 mmol/L, but also decreased tetrodotoxin (TTX) -resistant sodium current in relatively selective and dose-dependent manner with IC50 of 2.49 mmol/L. Conclusion The results suggested that ligustrazine could elevate the threshold of thermal nociception through inhibiting the high-voltage gated calcium current and TTX-resistant sodium current of DRG neuron in the rat. 相似文献
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3.
Zhang Gu-sheng章谷生 Hu Fang-yuan胡方远 Ye Qing-zhen叶庆祯 Yan Yong-tang严咏棠Immunology Laboratory Shanghai Institute of Biologicat Products Shanghai 《中华医学杂志(英文版)》1986,99(4):343-346
Neurotropin (NSP) is an extract isolated from
the skin of rabbits inoculated with vaccinia virus.
The present study examines the possible action of
NSP on the number and function of immunocompe
tent cells in mice. The experiment showed that NSP
had no effect on both T and B lymphocytes of nor-
malimmunized mouse spleen. The degree of plaque
forming cell reaction and titre of specific antibody
showed no significant differences when the NSP
treated group and controls were compared. How-
ever, NSP exhibited promotive effect on specific
antigen binding cells in the early stage of immune
responses. It was also noted that the rosette forming
capacity of human T lymphocytes in vitro was restor-
ed markedly by NSP. These results suggest that
NSP possesses certain immunostimulating activity,
particularly on the specific antigen binding cells and
human T lymphocytes. 相似文献
4.
Chai Ben-Fu柴本甫Shanghai Institute of Traunatology Orthopedics ShanghaiTang Xue-ming汤雪明Shanghai Second Medical College Shanghai 《中华医学杂志(英文版)》1986,99(2):126-132
Transmission electron microscopic investigation
of standardized fractures of radii in 50 rabbits re
vealed that fibroblasts took part in the formation of
bony callus. The osteogenetic role played by the
fibroblasts can be categorized into the following 5
aspects: a. Fibroblasts synthesize and secrete Type
collagen fibrils and induce deposition of calcium
salt crystals in the collagen fibrils. b. Fibroblasts
produce matrix vesicles in their surroundings. These
matrix vesicles become calcified and turn into floccu-
lent calcospherules which coalesce and fuse into bone
tissues. c. Fibroblasts harbor calcium granules in
their mitochondria, thus providing calcium for calci-
fication of the intercellular matrix and bone forma
tion between the cells. d. Fibroblasts can transform
directly into osteocytes; there is bone formation
around the fibroblasts, the bone tissues surround the
fibroblast in the form of bony lacuna, then the fibro-
blast in the lacuna transforms into osteocyte. e.
Fibroblasts can undergo degenerative changes leading
to decease and replacement by bone tissues. 相似文献
5.
Lin Yuan林原 Liu Tong-hua刘彤华and Li Shi-e李士谔Department of Pathology Peking Union Medical. College HospitaT. Chinese Acade'rnl of Medical Sciences Beijin! 《中华医学杂志(英文版)》1988,101(7):523-528
WiLh RNA-DNA dot blot technique, the expression of c-myc and N-ras oncogenes in human hepato
cellular carcinoma was found to be higher than in
tie non-cancerous liver tissue adjacent to the carci
noma (p<0.01). The expression of both oncogenes
was high in the fetal liver and gradually decreased
with age during development, indicating a probable
co-operation of c-myc and N-ras. Immunocytochemi-
cal analysis showed changes in protein products of
c-myc hepatocellular carcinoma and its nan
cancerous tissue were similar to those in mRNA
expression. The same was true for the fetal liver
during its development.
A comparable study was also made on the ex
pression of c-myc and N-ras oncogenes in limited
samples of human pancreatic adenocarcinoma and
its noncancerous tissue. The results are inconclu
sive, and further studies are needed. 相似文献
6.
With the method of rapid gel sequencing, the complete nueleotide sequence of Fasciolopsis buski 5S rRNA has been determined: AAC GGG AUG AAG CUA GAC AUG UGG CGG CCU AGU UGG AGG UCG GAA CUC GGA AGU UAA GGA AUG UUG GGC CUG GUU AGU ACU GGU AUG GGU GAC CUU GGG AAU ACC GGG UGU UGC GUC CA_(OH) This have been compared with 553 species of other organisms 5S rRNA sequences previously published and fitted to a secondary structural model. 相似文献
7.
Dongrun Tang Guoxiang Song Shimin Cui Lingen Chen Qingbin LiDepartment of Ophthalmology the Second Affiliated Hospital Tianjin Medical UniversityTianjin ChinaDepartment of Neurosurgery Tianjin Huan Hu Hospital 《眼科学报》1994,(3)
By digital subtraction angiography(DSA), the authors made observations on 108 normal ophthalmic arteries in 80 patients with regard to the origins, courses, branching, morphology and anastomoses of the vessels. The merits and demerits of DSA in observing the ophthalmic artery were discussed. Eye Science 1994; 10: 157- 162. 相似文献
8.
9.
Zhong Rui-kun钟瑞琨 Dong Yong-he董永和and Lu Dao-pei陆道培Institute of Hematology Beijing Medical University Beijing 《中华医学杂志(英文版)》1989,102(7):537-544
In order to understand the mechanism of immunosuppression caused by infusion of placental gamma globulin (PGG) in patients with renal allografts, rheumatoid arthritis, and graft – versus –host disease (GCHD) following bone marrow transplantation (BMT) ,we have examined the effect of PGG in vitro and in a model of the xenogeneic , local graft –ver- sus – host reaction (LGVHR) .PGG inhibited lymphocyte proliferation in mixed lymphocyte cultures (MLC) (P<0.005) and depressed interleukin -2 (IL-2) levels in such cultures at 72 hours (P<0.01) . In contrast phytohemagglutinin (PHA) –and pokeweed mitogen (PWM) –induced T and B lymphocyte blastogenesis was not affected by such PGG treatment .PGG treatment .PGG neither decreased the [3H] TdR pulse incorporation in unstimulated lymphocytes nor affected cell viability .Cell cycle analysis by flow cytometry showed that PGG reduced the percentage of cells in S and G2, M phases during the MLC, but did not alter cell cycling during PWM-stimulated proliferation .
An immunosuppressive effect of PGG on the LGCHR was tested in a model of intracutaneous transplantation of PGG –treat human lymphocytes into cyclophosphamide – immunosuppressed rats. Lymphoprep – separated human tonsillar lymphocytes were incubated with RPMI-1640 buffer containing:(1)PGG,4mg/ml,(2) human plasma albumin,4mg/ml,(3)mitomycin-C,25ug/ml, or (4) no additive. Cell of each preparation (3x107cells in 0.1ml) were injected intracutaneously into cyclophosphamide-treated male rats at separate abdominal locations. A fifth site received only the buffer solution. Five days after injection of cells ,each rat received [125 I]IUdR (10uCi) intraperitoneally and was killed after 5 hours. For each site of injection, the diameters of induration were measured and 125 I was counted . There was no difference between buffer – treated and a ibumin – treated groups either in the diameter of the area of induration (t=0.66;P>0.5)or in radioactive counts(t=0.22;P>0.05).In the PGG –treated group, the induration and radioactivity measurements were significantly less than in control groups (t=3.72 and P<0.1;t=2.62 and P<0.02,respectively ) Cytophilic antibodies in PGG were thought to inhibit an early phase of T cell activation, and not to be cytotoxicity .In the LGVHR, the immune response might be abrogated either by immuno- regulatory suppression of T cell function or by toxicity to the infused lymphoid cells. For some clinical purposes, immuno- modulating, human antibodies might be preferred to murine, monoclonal antibodies. 相似文献
10.