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931.
目的 了解大同市布鲁杆菌病(简称布病)流行现状,为制订预防决策提供科学依据。方法 通过全国传染病疫情网络直报系统,收集整理2006 - 2009年大同市7个县4个区人间布病疫情监测资料,建立Excel数据库,对全部数据进行统计分析。分析当地人群布病发病率,发病人群的地区分布、时间分布、职业分布、年龄性别分布,总结大同市人间布病流行趋势及特点。结果 2006 - 2009年大同市共发生布病5195例,平均发病率为57.51/10万。各县(区)均有发病,发病时间以春、夏季为主,发病人群以青壮年男性居多。农民发病人数占总发病人数的81.67%(4243/5195)。结论 2006 - 2009年,大同市人间布病疫情呈现“高—低—高”流行态势,建议有关部门加大重点县(区)的防治工作力度,对重点发病人群进行布病防护知识的宣传,提高农民自我防护意识。 相似文献
932.
C57黑鼠骨关节炎模型的关节病理积分与血清及滑膜中基质金属蛋白酶-3白细胞介素-1水平的相关性研究 总被引:1,自引:0,他引:1
目的 探讨基质金属蛋白酶(MMP)-3与白细胞介素(IL)-1在骨关节炎(OA)发病中所起的作用及其用于临床判断OA早期病理变化的可能性.方法 采用C57黑鼠OA模型.在自然增龄基础上,又对小鼠进行运动负荷训练.应用形态学方法对模型关节的病理切片观察,进行OA积分评分.研究采用酶联免疫吸附试验(ELISA)的方法.检测血清及滑膜中MMP-3、IL-1的水平.采用相关性分析来检验血清和滑膜中MMP-3、IL-1水平之间的关系,以及与OA积分评分之间的相关性.结果 ①形态学观察:C57黑鼠具有自发OA特征,其OA严重程度与周龄相关,且运动负荷可加快有自发OA倾向的小鼠关节软骨病理改变.②ELISA检测:运动负荷组滑膜中MMP-3[(84±6)ng/ml]、IL-1[(48±3)ng/ml]及血清中IL-1[(38.3±5.0 mg/ml]含量高于自然增龄组[滑膜MMP-3(71±5)ng,ml;IL-1(42±3)ng/ml;血清IL-1(8.1±2.4)ng/ml],差异有统计学意义(P<0.01);血清与滑膜中MMP-3、IL-1水平、OA评分存在线性相关[r均>0.67,P均<0.01].结论 联合检测MMP-3及IL-1在OA血清中的含量,有助于疾病的诊断与病情的判断.特别是MMP-3对于OA的早期诊断具有更为重要的意义. 相似文献
933.
N Arber EK Han A Sgambato GA Piazza TM Delohery M Begemann CM Weghorst NH Kim R Pamukcu DJ Ahnen JC Reed IB Weinstein PR Holt 《Gastroenterology》1997,113(6):1892-1900
BACKGROUND & AIMS: Mutations of c-K-ras occur commonly in colonic neoplasms. The aim of this study was to determine how c-K-ras mutations alter the responses to the chemopreventive agent sulindac. METHODS: The parental rat intestinal cell line IEC-18 and c-K-ras-transformed derivatives were treated with sulindac sulfide. Cell cycle distribution was determined by flow-cytometric analysis (fluorescence-activated cell sorter), apoptosis by DNA fragmentation (laddering), flow cytometry, and microscopy, and changes in gene expression by immunoblotting. RESULTS: Sulindac sulfide inhibited cell growth and induced apoptosis in a time- and dose-dependent manner more rapidly in and at lower concentrations in parental cells than ras-transformed cells. Expression of the sulindac sulfide arrested cells in G0/G1, but cells entered apoptosis throughout the cell cycle. Proapoptotic protein Bak was relatively high in untreated parental cells and increased markedly after sulindac sulfide but was low in untreated ras-transformed cells and did not increase after sulindac sulfide. Expression of other Bcl-2 family members was unchanged after sulindac sulfide. However, sulindac sulfide reduced levels of cyclin D1 protein and cyclin E- and cyclin D1- associated kinase activity. CONCLUSIONS: c-K-ras-transformed enterocytes are relatively resistant to sulindac sulfide-induced growth inhibition and apoptosis, which may result from specific reduction of bak expression. (Gastroenterology 1997 Dec;113(6):1892-900) 相似文献
934.
John Z. Ayanian M.D. M.P.P. Edward Guadagnoli Ph.D. 《Breast cancer research and treatment》1996,40(1):65-74
Summary Guidelines for the optimal treatment of breast cancer have been publicized over the past 15 years, yet clinical practices continue to vary substantially in the United States. This article reviews the literature on variations in local and systemic treatment of breast cancer by patient and provider characteristics.Studies of local therapy have consistently demonstrated that older women are less likely than younger women to receive radiation therapy after breast-conserving surgery. Some studies have noted that black women are less likely than white women to receive breast-conserving surgery and less likely to receive radiation therapy after breast-conserving surgery. Rates of breast-conserving surgery vary three-fold among geographic regions and between teaching and non-teaching hospitals. Patients at smaller hospitals appear less likely to receive indicated radiation therapy.Patterns of systemic therapy have not been well described. Women over age 75 may not be receiving adequate hormonal therapy, but recent data are not available. Limited data suggest that rates of systemic therapy do not vary substantially by race or Hispanic ethnicity, but women without health insurance may not be receiving appropriate chemotherapy. Studies relating hospital and physician characteristics to the use of systemic therapy are sparse and inconclusive.In order to increase the proportion of women who receive optimal treatment for breast cancer and ensure greater equity, a more sophisticated understanding of variations in clinical practice will be required. These variations may arise from insufficient knowledge of or disagreement with guidelines among physicians, inadequate communication between physicians and patients, and individual preferences or clinical attributes of patients. Future studies will need to explore the dialogue between women and their physicians that leads to decisions about treatment of breast cancer. 相似文献
935.
Participation of ADP in the binding of fibrinogen to thrombin- stimulated platelets 总被引:17,自引:0,他引:17
Thrombin and adenosine diphosphate (ADP) supported the binding of 125I- fibrinogen to washed human platelets with similar kinetics and affinity. Platelet secretion, as measured by 14C-serotonin release, and fibrinogen binding exhibited an identical dependence on thrombin concentration. Enzymatic removal of ADP with apyrase or creatine phosphate/creatine phosphokinase (CP/CPK) from thrombin-stimulated platelets markedly inhibited 125I-fibrinogen binding, but pretreatment of platelets with CP/CPK prior to thrombin stimulation was without effect. Thus, ADP, released from the platelet, participates in the binding of fibrinogen to thrombin-stimulated platelets. 相似文献
936.
Cytochemically demonstrable B-glucuronidase activity in normal and neoplastic human lymphoid cells 总被引:1,自引:0,他引:1
Mononuclear cell suspensions were prepared from 40 normal peripheral blood and lymphoid tissue specimens and 42 neoplastic specimens obtained from patients with malignant lymphoma and lymphocytic leukemia. These suspensions were analyzed for la antigens, surface immunoglobulin (Slg), sheep erythrocyte (E) rosette formation and, in some instances, acid alpha-naphthyl acetate esterase (ANAE) activity. The results of these studies were correlated with the expression of cytochemically demonstrable BG activity. The percentage of BG+ lymphocytes was found to be comparable, within 10%, to the percentage of E+ (T) cells in the majority of normal, non-neoplastic peripheral blood, tonsil, spleen, and lymph node specimens examined. Occasionally, the percentage of E+ cells exceeded the percentage of BG+ cells by 20% or more, suggesting the presence of an E+BG- T cell subpopulation. BG+ B lymphocytes were only demonstrated in 1 of 40 non-neoplastic lymphoid specimens. The neoplastic B cells in each of 14 B cell (la+Slg+E-) lymphomas were BG-. However, a variable proportion of the neoplastic cells isolated from 6 cases of B cell chronic lymphocytic leukemia and neoplastic plasma cells isolated from 7 cases of multiple myeloma expressed BG activity. Thus, it appears that both normal and neoplastic BG- and BG+ B lymphocyte populations exist; the latter may be related to a state of activation or a stage of B cell differentiation. The neoplastic cells isolated from 4 T cell (la-Slg-E+) malignancies were BG+ while those isolated from 3 T cell malignancies were BG-. The variable expression of BG activity by T cell malignancies may be related to T cell differentiation. Investigation of BG expression by T cell derived malignancies may prove useful in sorting out T cell phenotypes. 相似文献
937.
颞下颌关节骨关节病发展过程中诱导型一氧化氮合酶在其软骨组织内的表达和意义 总被引:1,自引:0,他引:1
目的研究颞下颌关节骨关节病(TMJOA)发生发展过程中诱导型一氧化氮合酶(iNOS)在其软骨组织内的表达和作用。方法采用山羊建立TMJOA动物模型,在各组动物注射胶原酶后的2、4、12、24周时,分别切取其TMJ标本做EnVision二步法免疫组化检测。结果正常组TMJ软骨无iNOS表达,在实验组动物TMJOA发病过程中其软骨组织iNOS的表达有明显增加,且随着病变过程的发展与病变组织有一定的对应性。结论iNOS在TMJOA发生发展过程中起着重要的作用,抑制iNOS的生成有可能会阻断TMJOA的发生和发展。 相似文献
938.
Daniel H. Solomon Elena Losina John A. Baron Anne H. Fossel Edward Guadagnoli Elizabeth A. Lingard Andrew Miner Charlotte B. Phillips Jeffrey N. Katz 《Arthritis \u0026amp; Rheumatology》2002,46(9):2436-2444