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991.
目的:观察肾小管上皮细胞的更新、再生有无来源于骨髓干细胞。方法:建立性别不匹配大鼠间的骨髓移植和肾脏移植模型,通过激光切割技术,将肾小管上皮细胞切割下来,提取其基因组DNA,用针对大鼠Y染色体上性别决定基因(Sry基因)的引物进行PCR反应,以观察提取的DNA中有无Sry基因。结果:据PCR反应结果,在2种模型所取标本的肾小管上皮细胞中,大部分可见Sry基因的存在。结论:骨髓干细胞可能是肾小管上皮细胞再生的一个来源。 相似文献
992.
Hiroshi Sonobe Jun Iwata Mutsuo Furihata Yuji Ohtsuki Hiroo Mizobuchi Hiroshi Yamamoto 《Pathology international》1994,44(5):407-411
Periosteal osteosarcoma is an exceedingly rare type of chondroblastic osteosarcoma, showing rather better prognosis, and secondary bone marrow involvement is unusual. A case of a 22 year old male with periosteal osteosarcoma of the right femur with an associated bone marrow lesion is presented. The juxtacortical tumor, 16 ×11 × 9 cm, was located on the bone cortex of the upper diaphysis and extended into the surrounding soft tissues. A minimal bone marrow lesion was present, although the bone cortex was quite intact. Microscopically, the tumor consisted exclusively of atypical chondroblastic cells with a small osteoblastic area. The bone marrow lesion, interestingly, contained both multiple nodules of well-differentiated chondrosarcomatous components and a few demarcated foci of atypical spindle cells producing a fine osteoid matrix. It was reasonable to conclude, therefore, that this tumor was a periosteal osteosarcoma with an unusual secondary bone marrow lesion rather than a conventional (central) chondroblastic osteosarcoma with soft tissue invasion. The patients good prognosis with no tumor recurrence or metastasis during more than 7 years follow-up after surgery supports this conclusion. 相似文献
993.
IgG inhibits the increase of platelet-associated C3 stimulated by anti-platelet antibodies 总被引:1,自引:0,他引:1
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S. Nomura Y. Miyazaki T. Miyake K. Yamaguchi H. Kido T. Kawakatsu T. Fukuroi H. Kagawa M. Suzuki M. Yanabu T. Kokawa 《Clinical and experimental immunology》1993,93(3):452-455
We investigated the increase of platelet-associated IgG and complement component 3 (C3) caused by the in vitro action of anti-platelet MoAbs, and the effect of mouse and human IgG on these events. Anti-glycoprotein IIb/IIIa and anti-glycoprotein Ib MoAbs caused a slight increase of C3, but not of platelet-associated IgG. In contrast, anti-CD9 and anti-Fcγ II receptor MoAbs caused an increase of both platelet-associated C3 and IgG. In particular, three MoAbs which activated the complement system caused a marked increase of C3. When platelet-rich plasma was treated with aspirin and prostaglandin E1 before incubation with antibodies, the increase of platelet-associated IgG was inhibited in all cases. In contrast, the increase of platelet-associated C3 was scarcely influenced. These results suggest that the binding to platelets of platelet-activating antibodies caused the increase expression of IgG molecules on the platelet surface and a possible increase of platelet-associated IgG. However, the increase of platelet-associated C3 appeared to depend on specific characteristics of the antibodies tested, such as a complement-activating effect. In addition, intact mouse or human IgG inhibited the increase of platelet-associated C3 caused by complement-activating antibodies, while F(ab')2 mouse or human IgG had no such effect. This suggested that the Fc portion of IgG may block the increase of C3 mediated by anti-platelet antibodies. 相似文献
994.
In order to confirm the role of 14-3-3 sigma (sigma) as a tumor suppressor in breast carcinogenesis, we have studied the expression of 14-3-3sigma immunohistochemically in usual ductal hyperplasia (UDH), ductal carcinoma in situ (DCIS) and invasive ductal carcinoma (IDC) breast lesions. Immunostaining for estrogen receptor alpha (ERalpha), p53 and estrogen-responsive RING finger protein (Efp) was also carried out. Immunohistochemically, expression of 14-3-3sigma was seen in 92% UDH lesions and gradually decreased from 65% in DCIS to 23% in IDC. The expression of ERalpha decreased gradually from UDH to DCIS to IDC, while p53 showed an inverse staining pattern to that of ERalpha. The expression of Efp showed no significant difference among the three breast lesions. Hence, the present immunohistochemical study confirmed 14-3-3sigma as a tumor suppressor in breast carcinogenesis. A similar immunohistochemical analysis was then carried out on columnar cell hyperplasia with atypia (CCHA), in which the expression pattern of tumor suppressor 14-3-3sigma, ERalpha and p53 suggested that it might be possible that CCHA is a precancerous lesion. 相似文献
995.
目的:通过观察无糖低氧(OGD)刺激对小鼠海马脑片内蛋白激酶C(PKC)特定亚型膜转位水平(激活程度)的影响,进一步证实我们在整体低氧预适应小鼠模型上所获实验结果,并为离体海马脑片缺血/低氧预适应(I/HPC)模型建立及后续药物干预实验打下基础。方法:急性分离小鼠海马组织、制备400!μm厚度的脑片,并用无糖低氧(OGD)人工脑脊液(ACSF)模拟缺血/低氧刺激;应用SDS-PAGE和Westernbolt等生化技术,并结合GelDoc凝胶成像系统,半定量检测OGD刺激2、5、10、15和30min后海马脑片内cPKCβII和nPKCε的膜转位水平。结果:OGD刺激可增高海马脑片内cPKCβII和nPKCε的膜转位水平,且这种增高从刺激5min开始持续至30min均有显著差异(P<0.001,n=6)。结论:实验结果进一步证实cPKCβII和nPKCε可能参与脑缺血/低氧性预适应的形成过程,并提示OGD10min作为制备离体海马脑片I/HPC模型的预处理刺激较为合理。 相似文献
996.
Hidai C Kawana M Habu K Kazama H Kawase Y Iwata T Suzuki H Quertermous T Kokubun S 《The anatomical record. Part A, Discoveries in molecular, cellular, and evolutionary biology》2005,287(2):1165-1175
In the present study, we established transgenic mice overexpressing Del1, a ligand of integrins, to examine the effect of overexpression of Del1 on vascular morphogenesis. In the wild-type mouse, mesenteric vessels are shaped like rakes consisting of a long stalk and short branches at the periphery. In contrast, those in transgenic mice showed typical dendritic architecture consisting of a few large primary branches with smaller spreading branches. The phenotype of mice overexpressing Del1 suggests the existence of a tissue-specific mechanism for branching morphogenesis in the mesentery. 相似文献
997.
Kuca K Cabal J Kassa J Jun D Hrabinová M 《Acta medica (Hradec Králové) / Universitas Carolina, Facultas Medica Hradec Králové》2005,48(2):81-86
(1) The efficacy of the oxime HL?7 and currently used oximes (pralidoxime, obidoxime, HI-6) to reactivate acetylcholinesterase inhibited by various nerve agents (sarin, tabun, cyclosarin, VX) was tested by in vitro methods. (2) Both H oximes (HL?-7, HI-6) were found to be more efficacious reactivators of sarin and VX-inhibited acetylcholinesterase than pralidoxime and obidoxime. On the other hand, their potency to reactivate tabun-inhibited acetylcholinesterase is very low and does not reach the reactivating efficacy of obidoxime. In the case of cyclosarin, the oxime HI-6 was only found to be able to sufficiently reactivate cyclosarin-inhibited acetylcholinesterase in vitro. (3) Thus, the oxime HL?-7 does not seem to be more efficacious reactivator of nerve agent-inhibited acetylcholinesterase than HI-6 according to in vitro evaluation of their reactivation potency and, therefore, it is not more suitable to be introduced for antidotal treatment of nerve agent-exposed people than HI-6. 相似文献
998.
Unlike the penetrating monoenergetic 662 keV gamma rays emitted by 137Cs LDR sources, the spectrum of 192Ir used in HDR brachytherapy contains low-energy components. Since these are selectively absorbed by the high-atomic number materials of which intracavitary applicators are made, the traditional neglect of applicator attenuation can lead to appreciable dose errors. We investigated the attenuation effects of a uterine applicator, and of a set of commonly used vaginal cylinders. The uterine applicator consists of a stainless steel source guide tube with a wall thickness of 0.5 mm and a density of 8.02 g/cm3, whereas the vaginal cylinders consist of the same stainless steel tube plus concentric polysulfone cylinders with a radius of 1 or 2 cm and a density of 1.40 g/cm3. Monte Carlo simulations were performed to compute dose distributions for a bare 192Ir-HDR source, and for the same source located within the applicators. Relative measurements of applicator attenuation using ion-chambers (0.125 cm3) confirmed the Monte Carlo results within 0.5%. We found that the neglect of the applicator attenuation overestimates the dose along the transverse plane by up to 3.5%. At oblique angles, the longer photon path within applicators worsens the error. We defined attenuation-corrected radial dose and anisotropy functions, and applied them to a treatment having multiple dwell positions inside a vaginal cylinder. 相似文献
999.
Zhang J Herman EH Knapton A Chadwick DP Whitehurst VE Koerner JE Papoian T Ferrans VJ Sistare FD 《Toxicologic pathology》2002,30(1):28-40
The characteristics and pathogenesis of the cardiovascular toxicity induced by the type III selective phosphodiesterase inhibitor SK&F 95654 were examined in 2 studies. Sprague-Dawley rats received either a single sc injection of 50, 100, or 200 mg/kg SK&F 95654 and were euthanized at 24 hours after administration of the drug (Study 1), or were given a single subcutaneous (sc) injection of 100 mg/kg SK&F 95654 and euthanized at 1, 2, 4, 6, 8,12, 24 hours, or 2 weeks after treatment (Study 2). Control rats received either DMSO or saline. Myocardial lesions and vascular lesions of the mesentery, spleen, and pancreas were seen 24 hours after dosing with either 50,100, or 200 mg/kg SK&F 95654. The frequency and severity of these lesions (evaluated after the 100 mg/kg dose) increased with time over a period of 1 to 24 hours. By 2 weeks, the lesions subsided. Cardiac lesions consisted of myocyte necrosis with hypercontraction bands, inflammatory cell infiltration, interstitial hemorrhage, and interstitial edema. Vascular lesions of the mesentery were most prominent and consisted of vasodilatation and inflammation in the small-sized vessels, arterial medial necrosis and hemorrhage, and venous thrombosis. The vascular lesions included: leukocyte adhesion to endothelial cells, transendothelial migration of leukocytes, and inflammatory cell infiltration into vessel walls. Affected vessels included arteries, terminal arterioles, capillaries, postcapillary venules, and veins. Apoptosis of endothelial and smooth muscle cells was detected in the mesenteric vasculature by both TUNEL assay and electron microscopy. Evidence of endothelial cell activation in the mesenteric arteries and veins was also observed by electron microscopy. Immunohistochemical staining detected enhanced endothelial cell expression of intercellular adhesion molecule- 1 (ICAM- 1) and von Willebrand factor (vWF) in the mesenteric arteries and veins. Mast cells were noted to be more prevalent in affected mesenteric tissue from drug-treated animals. The present findings suggest that apoptosis of endothelial and smooth muscle cells, activation of endothelial cells, recruitment of mast cells, and increased expression of adhesion molecules are important factors to the overall pathogenesis of SK&F 95654-induced vasculitis. 相似文献
1000.
云南省1999-2003年围产儿出生缺陷监测结果分析 总被引:1,自引:0,他引:1
目的为了解云南省围产儿出生缺陷的发生种类及分布情况,寻找影响出生缺陷的相关因素.方法 1999年1月-2003年12月监测云南省多所医院住院分娩孕28w-产后7d的围产儿.按全国出生缺陷统一标准要求,由医院逐季上报<围产儿数季报表>,<出生缺陷登记卡>至省妇幼保健院.结果围产儿出生缺陷率为10.26‰(1013/98690),指(趾)畸形;唇腭裂;神经管畸形是云南省围产儿出生缺陷前3位高发种类,男性出生缺陷发生率为10.84‰(561/51732)高于女性9.41‰(442/46958),城市高于乡村,产妇年龄≥35岁是出生缺陷的高发风险因素.结论进一步开展婚前生殖健康教育和医学检查,指导新婚妇女服用小剂量叶酸预防神经管畸形,加强全民健康教育,提高环境意识,做好婚前保健,优生和孕产期保健,开展产前筛查或产前诊断是减少出生缺陷发生的有力措施. 相似文献