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11.
目的了解广州地区2002年淋球菌对抗生素的耐药性及产青霉素酶淋球菌(PPNG)和高水平耐四环素淋球菌(TRNG)的流行状况。方法用琼脂稀释法测定四环素、壮观霉素、头孢三嗪和环丙沙星4种抗生素对100株淋球菌的最低抑菌浓度(MIC)及用纸片碘量法检测β-内酰胺酶。结果100株淋球菌检出PPNG 15株(15%)、TRNG 28株(28%),环丙沙星耐药率高达98%,高度耐药株(MIC≥16 mg/L)32株(32%),未发现对头孢三嗪、壮观霉素的耐药菌株,但头孢三嗪的敏感性有所下降。结论目前广州地区流行的淋球菌菌珠耐药状况仍然严重,尤以环丙沙星为甚,但对壮观霉素和头孢三嗪仍较敏感。此外,有必要持续监测球菌的耐药性。 相似文献
12.
医院感染常见细菌分布与耐药性分析 总被引:6,自引:0,他引:6
目的了解细菌分布及常见细菌的耐药性。方法回顾性分析某院2000—2004年临床标本分离的细菌及其耐药性监测结果。结果1439株细菌中,革兰阳性菌456株(31.69%),以凝固酶阴性表皮葡萄球菌为多,达206株(45.18%),其次为金黄色葡萄球菌92株(20.18%);两种葡萄球菌的耐药率相似,对万古霉素耐药率均为0。革兰阴性菌983株,前5位依次为肠杆菌属346株(35.20%),克雷伯菌属164株(16,68%),铜绿假单胞菌155株(15.77%),埃希菌属101株(10.27%),变形杆菌属94株(9.56%);前5位革兰阴性菌对常用抗菌药物的耐药性以半合成青霉索较明显,铜绿假单胞菌的耐药性较突出。结论应高度重视细菌变迁和耐药性监测,提高抗菌药物合理应用水平。 相似文献
13.
14.
目的:探讨地衣芽胞杆菌C01在模型小鼠体内对大肠杆菌、沙门氏菌抑制作用以及对乳杆菌等有益菌的促进作用。方法:用地衣芽胞杆菌C01灌胃肠道感染模型小鼠,采用体外活菌培养,分析粪便菌群数量的变化。结果:C01灌胃治疗组(EPEC C01)中乳杆菌的数量显著高于EPEC灌胃模型组(EPEC N)(P<0.01),肠杆菌数量下降极显著(P<0.01),而(EPEC N)组肠杆菌数显著高于正常对照组(NS)(P<0.05);肠炎沙门氏菌处理后C01灌胃治疗组(SL C01)和处理后肠炎沙门氏模型组(SL N)比较,乳杆菌、肠球菌和总厌氧菌的变化不明显,但肠杆菌数量下降极显著(P<0.01);形态病理学观察结果显示,C01芽胞杆菌灌胃治疗组肠粘膜病变明显减轻,肠粘膜及绒毛高度明显增加,绒毛轻度水肿,绒毛排列整齐、致密。结论:地衣芽胞杆菌C01在体内对肠炎沙门氏菌和致病性大肠杆菌有较强的抑制作用,能促进乳杆菌等生理性有益菌的增殖,可保护肠粘膜结构的完整性免受病原菌的侵袭。 相似文献
15.
左氧氟沙星治疗细菌性感染70例 总被引:40,自引:2,他引:38
目的:观察左氧氟沙星治疗细菌感染的疗效和安全性。方法:以左氧氟沙星治疗细菌性感染70例(男性35例,女性35例,年龄54±s15a),其中下呼吸道感染40例,尿路感染30例,剂量一般为0.2g,po,bid,疗程7~14d;单纯性下尿路感染为0.2g,po,qd,疗程5~7d。结果:总有效率93%,细菌清除率88%,不良反应轻微,呈一过性,发生率为6%。结论:左氧氟沙星治疗细菌性感染有效而安全。 相似文献
16.
Aseptic technology of vitrification of human pronuclear oocytes using open-pulled straws 总被引:4,自引:0,他引:4
Isachenko V Montag M Isachenko E Zaeva V Krivokharchenko I Shafei R van der Ven H 《Human reproduction (Oxford, England)》2005,20(2):492-496
BACKGROUND: The aim of this study was to compare the viability of human pronuclear oocytes subjected to vitrification using cooling by direct submerging of open-pulled straws in liquid nitrogen versus vitrification by cooling of open-pulled straws located inside a closed 0.5 ml straw (aseptic system). METHODS: Two- and three-pronuclei stage oocytes (n=114) were cryopreserved in super-open-pulled straws by vitrification in 20% ethylene glycol +20% dimethylsulphoxide (DMSO) + osmotic active and neutral non-permeable cryoprotectants with a four-step exposure in 20, 33, 50 and 100% vitrification solution for 2, 1 and 1 min, and 30-50 s, respectively at room temperature, and plunging into liquid nitrogen. Oocytes of group 1 (n=42) were rapidly cooled at a speed of 20,000 degrees C/min by direct plunging of open-pulled straws into liquid nitrogen. Oocytes of group 2 (n=44) were first located in 0.5 ml straws, which were closed at both sides by metal balls, and then plunged into liquid nitrogen. This method resulted in a cooling speed of 200 degrees C/min. For both groups, oocytes were thawed rapidly at a speed of 20 000 degrees C/min using an identical protocol. Oocytes subsequently were expelled into a graded series of sucrose solutions (1.0, 0.75, 0.5, 0.25 and 0.12 mol/l) at 2.5 min intervals. RESULTS: Oocyte development up to expanded blastocyst stage after in vitro culture was 15% in group 1, 14% in group 2 and 29% in an untreated control group. CONCLUSION: The deposition of human pronuclear oocytes in open-pulled straws which are placed inside a hermetically closed container guarantees a complete isolation of oocytes from liquid nitrogen and avoids potential contamination by pathogenic microorganisms. The combination of direct plunging of this container into liquid nitrogen and rapid warming makes this process as efficient as conventional vitrification. 相似文献
17.
Yewande E. Odeyemi ODene Lewis Julius Ngwa Kristen Dodd Richard F. Gillum Alem Mehari 《Journal of the National Medical Association》2019,111(1):94-100
Purpose
There is presently an ongoing debate on the relative merits of suggested criteria for spirometric airway obstruction. This study tests the null hypothesis that no superiority exists with the use of fixed ratio (FR) of forced expiratory volume in the first second (FEV1)/forced vital capacity (FVC) < 0.7 versus less than lower limit predicted (LLN) criteria with or without FEV1 <80% predicted in regards to future mortality.Methods
In 1988–1994 the Third National Health and Nutrition Examination Survey (NHANES III) measured FEV1 and FVC with mortality follow-up data through December 31, 2011. For this survival analysis 7472 persons aged 40 and over with complete data formed the analytic sample.Results
There were a total of 3554 deaths. Weighted Cox proportional hazards regression revealed an increased hazard ratio in persons with both fixed ratio and lower limit of normal with a low FEV1 (1.79, p < 0.0001), in those with fixed ratio only with a low FEV1 (1.77, p < 0.0001), in those with abnormal fixed ratio only with a normal FEV1 (1.28, p < 0.0001) compared with persons with no airflow obstruction (reference group). These remained significant after adjusting for demographic variables and other confounding variables.Conclusions
The addition of FEV1 < 80% of predicted increased the prognostic power of the fixed ratio <0.7 and/or below the lower limit of predicted criteria for airway obstruction. 相似文献18.
Korppi M 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2002,110(7-8):515-522
Seven paediatric studies on community-acquired pneumonia with serological methods for both viruses and bacteria have been published, allowing the evaluation of concomitant multiple etiological findings. In these studies, dual viral infection has been present in 0-14%, dual bacterial infection likewise in 0-14%, and mixed viral-bacterial infection in 3-30% of the pneumonia cases. The results confirm former clinical observations that respiratory viruses often pave the way for airway-colonising bacteria. The measured frequency of multiple infections has been dependent on the available test panel, mainly on the tests used for pneumococcal aetiology. Mixed viral-bacterial infections have been especially common in young children under 2 years of age, reflecting the high frequency of respiratory syncytial virus infections and their tendency to induce bacterial co-infections. No microbe-specific viral-bacterial associations have been demonstrated. The clinical implications of mixed viral-bacterial infections, compared with viral infections alone or bacterial infections alone, have so far remained unresolved. Current guidelines recommend antibiotic therapy for all community-acquired pneumonia cases in children. 相似文献
19.
Jan Schmeller Michael Wessolly Elena Mairinger Sabrina Borchert Thomas Hager Thomas Mairinger Kurt Werner Schmid Jeremias Wohlschlaeger Robert F.H. Walter Fabian D. Mairinger 《Pathology, research and practice》2019,215(2):381-386
Introduction
The usage of formalin-fixed paraffin embedded (FFPE) tissue is characterized by its long shelf-life and simple handling. Therefore it is the most commonly available tissue specimen in routine diagnostics and histological studies. Formaldehyde fixation may result in RNA degradation and cross linking with proteins, while storage conditions also affect RNA integrity. The present study was designed to investigate the influence of these factors on RNA analysis.Design
FFPE-derived RNA from sections of 23 patients with spontaneous pneumothoraxes was used. Unstained sections of FFPE tissue were stored at various temperatures (?80?°C, ?20?°C, 4?°C, 24?°C) prior to RNA extraction. The potential impact on RNA quality of semi-automatic and manual RNA isolation and three different deparaffinization agents (mineral oil, xylene and d-limonene) were compared.Results
The storage temperature of FFPE sections affects RNA concentration and fragmentation, with the optimal storage temperature below -20?°C. The RNA extracted with d-limonene shows equivalent quality to the RNA extracted using more toxic standard agents. The manual isolation provides a higher RNA yield compared to the semi-automatic isolation. However, no differences in the amount of longer RNA fragments were observed. Furthermore, the semi-automatic isolation showed an enhanced RNA quality.Conclusion
FFPE sections not directly used for RNA extraction should be stored below -20?°C to increase quality and yield of the RNA. Usage of semi-automatic isolation produces superior results and simplifies routine processes by having less hands-on-time. Replacement of toxic xylene by d-limonene may contribute to improved occupational safety while not influencing analytical results. 相似文献20.
The series equivalent resistance R and capacitance C of metal/saline electrode/electrolyte interfaces were measured as a function
of frequency (100 Hz–20k Hz) and current density (0·25 to 1000 A m−2) for eight typical electrode metals. For each of the metals tested, R decreased and C increased as the current density was
increased above a critical value (with the exception of silver and MP35N at frequencies above 1 kHz for which R increased
and C decreased slightly). With the exception of copper, the current density linearity limit (for 10 per cent decrease in
R or 10 per cent increase in C) increased with increasing frequency and, in most cases, the current density linearity limit
for 10 per cent increase in C was slightly less than that for 10 per cent decrease in R. Among the metals tested, copper and
aluminium had the lowest current carrying capability and rhodium had the highest current-carrying capability. The current
carrying capabilities of 316 SS, platinum, silver and MP35N, were intermediate and similar. With increasing current density,
an increase in the electrode/electrolyte capacitance was the most sensitive indicator of the current-carrying linearity limit. 相似文献