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81.
我们的实验发现,磁处理水对环磷酰胺等五种抗癌药物的毒性具有不同程度的缓解作用,能增加小鼠的存活率,能降低药物引起的白细胞减少。对目前癌化疗中使用率最高的环磷酰胺,其作用最明显。  相似文献   
82.
The quality of articular cartilage engineered using a cell-polymer construct depends, in part, on the chemical composition of the biomaterial and whether that biomaterial can support the chondrocytic phenotype. Acknowledging the supportive influence of tissue-specific matrix molecules on the chondrocytic phenotype, we have combined chondroitin sulfate-A (CSA) and chitosan, a glycosaminoglycan (GAG) analog, to develop a novel biomaterial to support chondrogenesis. Chitosan is a polycationic repeating monosaccharide of beta-1,4-linked glucosamine monomers with randomly located N-acetyl glucosamine units. Chitosan may be combined with the polyanionic CSA such that ionic crosslinking results in hydrogel formation. Bovine primary articular chondrocytes, when seeded onto a thin layer of CSA-chitosan, form discrete, focal adhesions to the material and maintain many characteristics of the differentiated chondrocytic phenotype, including round morphology, limited mitosis, collagen type II, and proteoglycan production. Our findings suggest CSA-chitosan may be well suited as a carrier material for the transplant of autologous chondrocytes or as a scaffold for the tissue engineering of cartilage-like tissue.  相似文献   
83.
Hereditary spastic paraplegia (HSP) is a heterogeneous group of inherited neurodegenerative disease characterized by progressive lower limb spasticity. Recent studies revealed that biallelic variants in RNF170 gene cause autosomal recessive complicated HSP with infancy onset. Here, we report an adolescent-onset HSP patient from a consanguineous Chinese family, with lower extremity stiffness, spastic gait, and unstable straight-line walking as the main manifestations. Whole-exome sequencing identifies a novel RNF170 mutation c.190C>T (p.R64*), which co-segregates with the disease in this pedigree. Functional analysis, including quantitative real-time PCR (RT-qPCR) and Western blot, indicates that both the mRNA and protein levels of mutant RNF170 are significantly reduced, which confirms the loss-of-function mechanism. Our study expands the spectrum of RNF170-associated HSP, while the RNF170 protein-involved degradation of the inositol 1,4,5-trisphosphate receptor in neurodegenerative motor neuron disorders deserves further investigation.  相似文献   
84.
Quinolin-2-one represents an important and valuable chemical motif that possesses a wide variety of biological activities; however, the anti-influenza activities of quinolin-2-one-containing compounds were rarely reported. Herein, we describe the screening and identification of 3-aryl-quinolin-2-one derivatives as a novel class of antiviral agents. The 3-aryl-quinolinone derivatives were synthesized via an efficient copper-catalyzed reaction cascade that we previously developed. Using this synthetic method, preliminary structure–activity relationships of this scaffold against the influenza A virus infection were systematically explored. The most potent compound 34 displayed IC50 values of 2.14 and 4.88 μM against the replication of H3N2 (A/HK/8/68) and H1N1 (A/WSN/33) strains, respectively, without apparent cytotoxicity on MDCK cells. We further demonstrated that 27 and 34 potently inhibited the plaque formation of the IAV, rendering this scaffold attractive for pursuing novel anti-influenza agents.  相似文献   
85.
Clonal analysis of mndne T cells has led to the idenuncation of Z typeS of Th cells, Thl and on. Thl cells,chacterized by secreting interferon-y (Iap-Y), interleukin-2 (IL2) and tumor necrosis factor-5 (TNF-3), involved Principally in cell-mediated ~ity and play acrucial role in defending the host against intracellularPathogens such as a Vallety of yi~es. ThZ cells,secreting IL4, ms, IL-6 and ilo, mostly regulateh~ immune responSe, and may oafs Paxtial PIDtection against extracellula…  相似文献   
86.
目的 为在肺癌的外科治疗过程中减少并发症的发生率,提高手术治疗效果。方法 对前期(1972年2月至1989年2月)与后期(1989年3月至1999年2月)的1178例肺癌病例在麻醉方法、手术入路、肺根及癌灶的处理、手术并发症的发生率和死亡率等方面进行了分析比较。结果 手术时间由平均217min减少至129min;术中输血量由平均830ml减少至460ml;呼吸衰竭发生率由3.4%降至1.5%;急性  相似文献   
87.
社区老年高血压病人健康教育近期效果评价   总被引:1,自引:0,他引:1  
为了解在社区老年高血压患者中进行的联合型健康教育活动的近期效果,作者重复调查了健教组社区老年人有关高血压“知-信-行”的状况,与基线和对照组的情况进行了比较分析。结果表明:本次联合型的健康教育活动使健教组在高血压的相关知识、信念、行为方面均有一定的改善。作者还对这项联合型健康教育活动的可行性及存在的问题进行了讨论。总结了本次研究的体会,并指出了进一步提高这项活动效率、效果的工作重点和建议。  相似文献   
88.
Chie W  Fu C  Lee W  Li C  Huang C  Chang K  Lin R 《Oncology reports》1997,4(5):1039-1043
One hundred and seventy-five pathologically confirmed new cases of female breast cancer in National Taiwan University Hospital were selected as the case group. Four hundred and fifty-seven inpatient controls were individually matched for each case by age and date of admission. Information of reproductive factors and potential confounders were collected from questionnaire interview and medical records. Menstrual cycles before and after first fuIl-term pregnancy were estimated from the questionnaire. Conditional logistic regression was used to estimate the effects of reproductive risk factors and numbers of menstrual cycles before and after first full-term pregnancy. After adjusting for educational level, body mass index, family history of breast cancer and oral contraceptive use, age at menarche and menopause only showed borderline significance. Age at first full-term birth predicted breast cancer risk better. Parity was the most important protective factor. Number of menstrual cycles before first full-term pregnancy was also positively associated with breast cancer risk with linear trends.  相似文献   
89.
Objective: The objective of this study was to determine whether human papillomavirus (HPV) infections are involved in the development of papillomatosis lesions of the lower female genital tract.Methods: A total of 616 biopsy specimens of genital papillomatous lesions (307 nodular and 309 papular types) from 598 patients were anaylyzed for the presence of HPV DNA sequences by polymerase chain reaction (PCR). These specimens were also examined by histopathological assessment for characteristic HPV-associated cytological changes, by immunohistochemical staining for HPV-associated antigen, and by electron microscopy for the presence of virions.Results: HPV DNA sequences were found in 97.9% (140 of 143 cases) and 1.1% (1 of 91 cases) of the nodular and papular papillomatosis cases tested, respectively. In 18 patients who had both types of papillomatosis lesions, HPV DNA was invariably found only in nodular tissues. HPV-associated antigen, koilocytosis, and virions were found in 53.6% (98 of 183 cases), 70.5% (129 of 183 cases), and 5.9% (5 of 85 cases) of nodular papillomatosis lesions tested, respectively.Conclusions: These data suggest that nodular papillomatosis was closely associated with HPV infection, but that papular papillomatosis of the lower female genital tract may have an etiology other than HPV infection.  相似文献   
90.
目的观察正常及模拟“缺血”时胺碘酮对绵羊心室浦肯野纤维起搏离子流(If)的影响。方法双微电极电压钳制术,使膜电位过度极化以激活If。结果胺碘酮1×10-5mol/L在正常台氏液中显著降低浦肯野纤维If幅值;模拟“缺血”也使If幅值降低,在此基础上,胺碘酮使If幅值进一步减小,加剧了“缺血”对If离子流的抑制作用。结论提示胺碘酮能抑制心肌缺血时心室正常自律性活动。  相似文献   
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