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101.
BACKGROUND AND PURPOSE: Nosocomial methicillin-resistant Staphylococcus aureus (MRSA) infection is difficult to control. Due to a dramatic increase in the nosocomial MRSA infection rate at our hospital from 2000 to 2001, this study was conducted to identify the source of these infections and the effectiveness of control measures. METHODS: 179 healthcare workers (HCWs) were screened for carriage of MRSA. Starting in April 2001, all patients with MRSA infection or colonization were put in strict contact and cohort isolation. The bacterial isolates of HCW carriers and patients with MRSA infection from April 2001 to September 2001 were subjected to antimicrobial susceptibility testing by disk-diffusion method and molecular typing by pulsed-field gel electrophoresis (PFGE). RESULTS: Fifteen HCWs were found to be carriers of MRSA. They were all given topical mupirocin treatment. After these interventions, the nosocomial MRSA infection rate decreased from 1.23 to 0.53 per 1000 patient-days. All 61 MRSA isolates available for antimicrobial susceptibility testing and molecular typing were multidrug resistant. PFGE study revealed 2 predominant types, type C and type Y, comprising 36 and 12 isolates, respectively. CONCLUSIONS: The current study demonstrates the importance of measures to control nosocomial MRSA infections in hospitals that already have a high incidence of endemic MRSA infection. Elimination of carriage by healthcare workers, and strict contact and cohort isolation are the main effective measures.  相似文献   
102.
火把花根片对哮喘豚鼠气道炎症抑制作用的实验研究   总被引:3,自引:0,他引:3  
目的 研究火把花根片对哮喘豚鼠气道炎症的作用。方法 建立哮喘豚鼠动物模型。豚鼠17只随机分为2组,即对照组(8只)和火把花根组(9只)。测定支气管肺泡灌洗液(BAIF)细胞总数、嗜酸性粒细胞、淋巴细胞、中性粒细胞数量及蛋白浓度,图像分析软件测定气道壁厚度及腺体厚度。结果 火把花根组BAIF细胞总数、嗜酸性较细胞为主的炎性细胞数量及蛋白浓度均低于对照组(P<0.01),图像分析表明火把花根组气道壁厚度及腺体厚度均较对照组减低(P<0.01)。结论 火把花根片可抑制哮喘豚鼠的气道慢性炎症,对支气管哮喘有治疗作用。  相似文献   
103.
增生性玻璃体视网膜病变基质金属蛋白酶的定量研究   总被引:5,自引:0,他引:5  
目的:研究增生性玻璃体视网膜病变(proliferative vitreoretinopathy,PVR)玻璃体中基质金属蛋白酶(matrix metalloproteinases,MMPs)的表达,探讨MMPs在PVR病理过程中的作用。方法:PVR患者采用标准三切口巩膜扁平部玻璃体切割术(pars plana vitrectomy,PPV),取未稀释的玻璃体21只眼,PPV术后复发的玻璃体腔液20只眼,意外死亡的正常人玻璃体10只眼,采用明胶酶谱分析法定量分析MMP-2和MMP-9活性水平。结果:PVR玻璃体有MMP-2活性水平增高,与正常玻璃体比较差异有显著性意义(P<0.05)。21眼PVR玻璃体中13只眼有MMP-9活性水平增高,平均(171.52±13.17)扫描单位。20眼PPV术后PVR复发的玻璃体腔液19只眼有MMP-9活性水平增高,平均(156.01±37.21)扫描单位。正常人玻璃体无MMP-9的表达。结论:PVR玻璃体有MMP-2和MMP-9活性水平增高,MMP-9活性水平增高可能与术后PVR复发有关。眼科学报2003;19:130-132。  相似文献   
104.
105.
OBJECTIVE: Our objective was to determine whether the observed relaxation to lactate and other agents in placental vessels of normal pregnancies is altered in severe preeclampsia.STUDY DESIGN: Isolated placental arteries and veins from women with severe preeclampsia and uncomplicated term pregnancies were precontracted with prostaglandin F under 5% oxygen and 5% carbon dioxide with the balance nitrogen (Po2 35 to 38 torr) and then exposed to lactate (1 to 10 mmol/L, pH 7.4, n = 8 to 15), arachidonic acid (0.01 to 10 μmol/L, n = 6 to 13), nitroglycerin (1 nmol to 1 μmol/L, n = 4 to 12), or forskolin (0.01 to 10 μmol/L, n = 6 to 9). The response to lactate was also examined in placental vessels from appropriate-for-gestational-age preterm deliveries (n = 8) for comparison with a similar group with severe preeclampsia (n = 8). The t test and analysis of variance statistics were used.RESULTS: Relaxation to lactate was markedly inhibited in both placental arteries and veins of women with severe preeclampsia compared with vessels from uncomplicated term or preterm pregnancies. Responses to the other relaxing agents were not altered in the severely preeclampsia vessels.CONCLUSIONS: In severe preeclampsia absence of lactate-induced dilatation of placental vessels may contribute to the fetal complications associated with impaired blood flow and vasospasm.  相似文献   
106.
The partial pressure of oxygen (pO2) of the liver in vivo in unanesthetized mice was determined using electron paramagnetic resonance (EPR) oximetry with India ink. The EPR spectra were obtained using a low-frequency (1.2 GHz) EPR spectrometer with a loop gap cavity resonator. The line width of the India ink used in this experiment was reversibly broadened by oxygen and was particularly sensitive to pO2 below 30 torr. After the administration of India ink into the tail vein, the India ink particles were taken up mainly by Kupffer cells in the liver and in part by phagocytes in the spleen. The pO2 measured in the normal liver was about 14 torr and was constant for the 2-week experimental period. The pO2 decreased when measured at 1, 2, and 6 days after treatment with a hepatotoxin (carbon tetrachloride (CCI4)); within 2 weeks, it returned almost to the initial level. Measurements by EPR at sacrifice of controls and CCI4-treated mice indicated that more than 90% of the India ink went to the liver; the spleen contained 4.7% of total amount in control mice and 8.8% in CCI4-treated mice when measured 2 weeks after the treatment. These data indicate the usefulness of India ink for measuring the pO2 of the liver in vivo and that the pO2 in the Kupffer cells is decreased when the liver is damaged by CCI4.  相似文献   
107.
胎儿腹壁异常的超声诊断   总被引:5,自引:0,他引:5  
本文总结了胎儿腹壁异常12例,其中脐疝4例,腹壁缺损4例、膈疝3例、胸腹壁缺损1例。分析了超声图像特点及漏诊、误诊原因,并提出鉴别诊断要点及最早诊断时间。对分娩方式及时间选择有重要意义。  相似文献   
108.
109.
This is first report about the simultaneous over-expression of both Insulin-like growth factor (IGF-II) and its receptor (IGF-II R) at mRNA level in human primary hepatic Cancer (PHC). In 10 PHC samples from China, IGF-II and IGF-II R were both over-expressed, whereas only a background signal was detected in normal liver. In 5 pairs of PHC and its non-tumorous adjacent liver tissues from South Africa, IGF-II and IGF-II R were also over-expressed in PHC. mRNA expression of IGF-II in all 5 cases and IGF-II R in 4 of 5 cases were higher in cancer than non-tumorous adjacent liver tissues. These results strongly implicate that an autocrine and/or paracrine mechanism might be involved in formation and progression of PHC.  相似文献   
110.
Twenty-eight breasts of 15 patients with macromastia underwent reduction mammaplasty from 1982 to 1989. We followed up these patients postoperatively for 6 months to 7 years. The follow-up time for 8 patients was over 1 year, and 4 patients over 5 years. And 3 patients labored and lactated. These 15 patients were satisfied with this operative results. The operative technology was based on Pitange's method. This method improved the site of the nipple, transposition of nipple-areola complex, and design of dermal pedicle, so that it had better effects in the breast shape, breast fixation and incision scar concealed. We suggest that the purpose of macromastia treated in reducing volume, improving breast shape, preserving lactating function. This paper also discusses the methods for nipple site, nipple-areola complex transposition, breast resection and mastopexy.  相似文献   
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