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Objective To observe the earlier pathological character and mechanism of radiation osteonecrosis in femoral head, in order to provide evidences for the earlier diagnosis and prevention of radiation osteonecrosis of femoral head. Methods Single femoral head of rats were irradiated singly with 30 Gy of 137 Cs γ-ray. The rats were executed after 2, 6 and 12 weeks, then the femurs were stained with HE and histopatholngical changes were observed by light microscope. The bone marrow mesenchymal stem cells (BMSCs) were cultured after 2 weeks and its proliferation and the colony formation were observed. The rats were endo-perfused with microfili contrast medium 12 weeks later, and the 3-dimensional structure of capillaries by Micro-CT was re-estabhshed to detect the pathological changes of capillaries after irradiation. Result The irradiated femur showed deranged cbondrocyte, decreased osteocyte, shrinking nucleus, increased empty bone lacuna and reduced bone trabocnla (P < 0.05). Micro-CT showed the discontinued small vessels and absence(6.65 %) capillaries in irradiated femur were obviously less than those of the unirradiated (12.3 %)(P < 0.001). The proliferation of BMSCs was slowed, the number of colony in irradiated group (10 %) was less than that of control (21 %) (P < 0.001). Conclusions The preliminary histopathological changes of osteoradionecrosis on femoral head could be increased the empty bone lacuna, and the bone lacuna above 30 % was the sign of the earlier period of osteoradionecrosis. The osteonecrosis of femoral head induced by radiation is not only correlated to the damages to the bone, but also to the damages to BMSCs and capillaries.  相似文献   
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U.urealyticumisthesmallestprokaryoticorgan ismcapableofself replication.Thetinymicroor ganismcouldbeisolatedfromurogenital,placen tasandtherespiratorytractsofpreterminfants.Moreover,U.urealyticuminfectionmaybein volvedinnon specificurethritis(NSU),prostati tis,postpartumfever,infertility,pelvicinflamma torydisease,neonatalpneumoniaandevenchronic lungdisease(CLD)[1].ItisknownthatU.urealyticumlackscellwallstructureandcontains abundantmembraneproteins,butitspathogenicity isstillunknownclearly.…  相似文献   
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To investigate the HLA-A, -B allele polymorphism in Han population of Shandong province and to explore the possibility to find out the HLA-A, -B-matched cord blood donors for stem cell transplantation to be used in other area in China, 5844 umbilical cord blood samples were taken from Han population donors of Shandong province, and assayed with PCR-sequence-oligonucleotide (PCR-SSO) assay. In Shandong Han donors, 20 alleles at HLA-A locus and 46 alleles at HLA-B locus could be detected as revealed in the present study. Among the 20 alleles at HLA-A locus, the most prevalent five alleles included A * 02(0.3041), A * 11(0.1443), A * 24(0.1434), A * 30(0.0975) and A * 33(0.0859), while, the alleles with lower gene frequencies included A * 34(0.0006), A * 25 (0.0005), A*66(0.0005), A* 74(0.0004) and A* (0.0001). Of the 46 HLA-B alleles detected, the most prevalent five alleles were B * 13(0.1348), B * 51(0.0713), B * 62(0.0712), B * 61 (0.0676) and B * 60(0.0642); while alleles with lower gene frequencies included B * 77(0.0001), B * 76(0.0002), B * 47(0.0003), B * 42(0.0003) and B * 72(0.0004). In comparison with those of the other Han population in China, the HLA-A, -B gene frequencies in the umbilical cord blood of Shandong province possess unique distribution features among the investigated populations from various regions of the same race origin, and the differences in various regions of the same race were less than those among the different race. It is evident that the HLA-A,-B alleles of the umbilical cord blood taken in Shangdong province show high degree of polymorphism, and it might be part of those of Northern Han population in China. So, it is reasonable for patients of Northern Chinese to receive HLA class I -match transplant of cord blood stem cells for tissue and organ transplantation from Shangdong umbilical cord blood bank.  相似文献   
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目的分析新型歼击机飞行员改装体检不合格原因的动态变化。方法对2004~2008年间102名新型歼击机飞行员改装体检不合格的资料进行综合分析,并与我们曾报道的1999-2003年间的相关资料比较。结果改装体检不合格的原因中,离心机检查未达标59例,外科病症26例,内科病症9例,神经科病症4例,耳鼻喉科病症3例,眼科病症1例,分别占改装体检不合格的58.4%、25.7%、7.9%、4.0%、3.0%、和0.9%。  相似文献   
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随着高新机种装备部队,对飞行人员综合素质要求更高,同时给航卫保障工作提出了更高的要求,传统型保障已经不能适应新的作战、训练模式的转变。新的保障装备配备部队使用,在实时监测飞行员状态变化、提高飞行耐力、缓解疲劳等方面带来了革命性的变化,但抛弃传统经验,将会使航卫保障工作走向教条化。所以将来的航卫保障模式将是精确型与经验型的结合。  相似文献   
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BACKGROUND: The aim of the study presented here was to examine the accuracy of ureteroscopic biopsy in the diagnosis of upper urinary tract transitional cell carcinoma (TCC) and whether nephron-sparing management (holmium YAG laser, transurethral resection or partial ureterectomy) is possible or not based on pathological diagnosis. METHODS: Forty consecutive patients underwent ureteroscopic biopsy with the use of 3-Fr cold cup forceps. Pathological diagnosis of the biopsy sample and grade or stage of surgically resected tumors were compared. In patients with grade 1 or 2 TCC diagnosed by ureteroscopic biopsy, the disease-free and survival rates determined whether nephron-sparing management was performed or not. RESULTS: There were no major complications associated with ureteroscopic biopsy. The pathological grading of the biopsy specimen was almost the same as that of the surgically resected specimen. Eighty five percent of grade 2 or 3 TCC showed muscle invasive disease. There were no significant differences in the disease-free and survival rates between the nephroureterectomy and the nephron-sparing management groups, except for grade 3 or pT3 tumors. CONCLUSION: Ureteroscopic biopsy is safe and accurate if sufficient tissue sample is obtained. Ureteroscopic biopsy should be performed in patients who require nephron-sparing management. Nephroureterectomy can be avoided if the tumor is confirmed as low-grade.  相似文献   
20.
Objective To observe the earlier pathological character and mechanism of radiation osteonecrosis in femoral head, in order to provide evidences for the earlier diagnosis and prevention of radiation osteonecrosis of femoral head. Methods Single femoral head of rats were irradiated singly with 30 Gy of 137 Cs γ-ray. The rats were executed after 2, 6 and 12 weeks, then the femurs were stained with HE and histopatholngical changes were observed by light microscope. The bone marrow mesenchymal stem cells (BMSCs) were cultured after 2 weeks and its proliferation and the colony formation were observed. The rats were endo-perfused with microfili contrast medium 12 weeks later, and the 3-dimensional structure of capillaries by Micro-CT was re-estabhshed to detect the pathological changes of capillaries after irradiation. Result The irradiated femur showed deranged cbondrocyte, decreased osteocyte, shrinking nucleus, increased empty bone lacuna and reduced bone trabocnla (P < 0.05). Micro-CT showed the discontinued small vessels and absence(6.65 %) capillaries in irradiated femur were obviously less than those of the unirradiated (12.3 %)(P < 0.001). The proliferation of BMSCs was slowed, the number of colony in irradiated group (10 %) was less than that of control (21 %) (P < 0.001). Conclusions The preliminary histopathological changes of osteoradionecrosis on femoral head could be increased the empty bone lacuna, and the bone lacuna above 30 % was the sign of the earlier period of osteoradionecrosis. The osteonecrosis of femoral head induced by radiation is not only correlated to the damages to the bone, but also to the damages to BMSCs and capillaries.  相似文献   
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