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51.
We describe two type 2 diabetic patients with unilateral emphysematous pyelonephritis who responded to medical treatment alone. Escherichia coli was isolated in both patients. The presence of gas was confirmed early by ultrasound and CT scan of abdomen. Following treatment, good functional recovery was demonstrable in the affected kidneys by isotope renogram. We stress the need for early diagnosis of this condition and aggressive treatment with broad spectrum antibiotics.  相似文献   
52.
目的:临床局部辐射条件下会造成非辐射区域组织及细胞功能损害,最为突出的是对造血功能的影响。实验建立60Coγ射线左半身辐射动物模型,观察局部电离辐射对其非辐射区域骨髓巨核细胞的影响。方法:实验于2003-10/2005-03在解放军第三军医大学辐照中心和全军复合伤研究所完成。①实验动物:6~8周龄SPF级雄性昆明小鼠180只,随机数字表法分为正常对照组、全身辐射组、左半身辐射组、全身屏蔽辐射组,45只/组。②实验方法:全身辐射组小鼠固定于辐射架内;左半身辐射组小鼠麻醉后固定体位,用铅砖屏蔽右半身;全身屏蔽辐射组小鼠麻醉固定体位,用铅砖屏蔽全身。以60Coγ射线一次性辐射,剂量率68.46cGy/min。正常对照组不作任何干预。③实验评估:辐射后不同时相检测小鼠血清丙二醛含量及超氧化物歧化酶活性变化,计数外周血血小板,检测骨髓巨核祖细胞集落形成单位,观察骨髓组织病理改变及CD41a、CD61的表达。结果:全身辐射组第8天死亡2只,第9天死亡4只,其余各组无脱失。①外周血血小板计数:辐射后第2,7天,左半身辐射组外周血血小板数量显著低于正常对照组(P<0.01),但高于全身辐射组(P<0.01)。②血清丙二醛含量及超氧化物歧化酶活性变化:辐射后第2,9天,左半身辐射组血清丙二醛含量显著高于正常对照组(P<0.01),低于全身辐射组(P<0.01);血清超氧化物歧化酶活性显著低于正常对照组(P<0.01),高于全身辐射组(P<0.01)。③骨髓巨核祖细胞集落形成单位的变化:与正常对照组比较,辐射后6h左半身辐射组非辐射侧的巨核祖细胞集落形成单位显著降低(P<0.01),高于全身辐射组及左半身辐射组(P<0.01)。④骨髓组织病理改变:正常对照组有核细胞比例较高,分布均匀,并见多量散在分布的细胞龛;辐射2d后,左半身辐射组非辐射侧骨髓有核细胞较正常对照组减少,但好于全身辐射组、左半身辐射组。⑤骨髓CD41a及CD61表达的变化:辐射后2d与正常对照组比较,左半身辐射组非辐射侧骨髓CD41a及CD61阳性细胞数和相对荧光强度均显著降低(P<0.01),但高于全身辐射组、左半身辐射组(P<0.01)。结论:局部电离辐射作用后,可导致小鼠非辐射区域骨髓巨核细胞增殖能力降低,血小板减少,产生功能障碍。氧自由基激活可能参与了该损伤过程。  相似文献   
53.

Background and purpose:

Chemokines orchestrate neutrophil recruitment to inflammatory foci. In the present study, we evaluated the participation of three chemokines, KC/CXCL1, MIP-2/CXCL2 and LIX/CXCL5, which are ligands for chemokine receptor 2 (CXCR2), in mediating neutrophil recruitment in immune inflammation induced by antigen in immunized mice.

Experimental approach:

Neutrophil recruitment was assessed in immunized mice challenged with methylated bovine serum albumin, KC/CXCL1, LIX/CXCL5 or tumour necrosis factor (TNF)-α. Cytokine and chemokine levels were determined in peritoneal exudates and in supernatants of macrophages and mast cells by elisa. CXCR2 and intercellular adhesion molecule 1 (ICAM-1) expression was determined using immunohistochemistry and confocal microscopy.

Key results:

Antigen challenge induced dose- and time-dependent neutrophil recruitment and production of KC/CXCL1, LIX/CXCL5 and TNF-α, but not MIP-2/CXCL2, in peritoneal exudates. Neutrophil recruitment was inhibited by treatment with reparixin (CXCR1/2 antagonist), anti-KC/CXCL1, anti-LIX/CXCL5 or anti-TNF-α antibodies and in tumour necrosis factor receptor 1-deficient mice. Intraperitoneal injection of KC/CXCL1 and LIX/CXCL5 induced dose- and time-dependent neutrophil recruitment and TNF-α production, which were inhibited by reparixin or anti-TNF-α treatment. Macrophages and mast cells expressed CXCR2 receptors. Increased macrophage numbers enhanced, while cromolyn sodium (mast cell stabilizer) diminished, LIX/CXCL5-induced neutrophil recruitment. Macrophages and mast cells from immunized mice produced TNF-α upon LIX/CXCL5 stimulation. Methylated bovine serum albumin induced expression of ICAM-1 on mesenteric vascular endothelium, which was inhibited by anti-TNF-α or anti-LIX/CXCL5.

Conclusion and implications:

Following antigen challenge, CXCR2 ligands are produced and act on macrophages and mast cells triggering the production of TNF-α, which synergistically contribute to neutrophil recruitment through induction of the expression of ICAM-1.  相似文献   
54.
STUDY OBJECTIVE: To determine the structural and functional consequences of high-frequency neuromuscular electrical stimulation (hf-NMES) in a group of moderately impaired outpatients with chronic obstructive pulmonary disease (COPD). DESIGN: A prospective, cross-over randomized trial. SETTING: An university-based, tertiary center. PATIENTS AND MATERIALS: Seventeen patients (FEV(1)=49.6+/-13.4% predicted, Medical Research Council dyspnoea grades II-III) underwent 6-weeks hf-NMES (50Hz) and sham stimulation of the quadriceps femoris in a randomized, cross-over design. Knee strength was measured by isokinetic dynamometry (peak torque) and leg muscle mass (LMM) by DEXA; in addition, median cross-sectional area (CSA) of type I and II fibres and capillary-fibre ratio were evaluated in the vastus lateralis. The 6-min walking distance (6MWD) was also determined. RESULTS: At baseline, patients presented with well-preserved functional capacity, muscle strength and mass: there was a significant relationship between strength and type II CSA (P<0.05). NMES was not associated with significant changes in peak torque, LMM or 6MWD as compared to sham (P>0.05). At micro-structural level, however, electrical stimulation increased type II, but decreased type I, CSA; no change, however, was found in the relative fibre distribution or capillary:fibre ratio (P<0.05). There was no significant association between individual changes in structure and function with training (P>0.05). Post-NMES increase in type II CSA was inversely related to baseline mass and strength (P<0.05). CONCLUSION: NMES may promote a modest degree of type II muscle fibre hypertrophy in COPD patients with well-preserved functional status. These micro-structural changes, however, were not translated into increased volitional strength in this sub-population.  相似文献   
55.
Background Negative surgical margins minimize the risk of local recurrence after breast-conserving surgery. Intraoperative frozen section analysis (FSA) is one method for margin evaluation. We retrospectively analyzed records of patients who received breast-conserving therapy with intraoperative FSA of the lumpectomy cavity to assess re-excision rates and local control. Methods Records were retrospectively reviewed for individuals who underwent breast-conserving surgery for ductal carcinoma in situ (DCIS) or invasive carcinoma between 1993 and 2003. Inclusion criteria were a minimum of 2 years follow-up and intact tumor at the time of operation. The major outcome measure was local recurrence. The Kaplan-Meier test was used to evaluate local recurrence rates between groups. Results 290 subjects with an average age of 57.2 years (range 27–89) underwent 292 lumpectomies with FSA. 11.3% had DCIS, 73.3% had infiltrating ductal, 5.8% had infiltrating lobular, and 9.6% exhibited other forms of invasive carcinoma. 70 subjects underwent additional resection at the time of breast surgery, 16 underwent subsequent re-excision, and 17 underwent subsequent mastectomy. At a median follow-up of 53.4 months (range 5.8–137.8), there were six local recurrences (2.74%) in patients who had breast-conserving procedures and two local recurrences in patients who underwent mastectomy. There were no statistically significant associations among local recurrence rate, tumor size, nodal status, or overall stage. Local recurrences were higher in patients with DCIS compared with invasive carcinoma, and tumors >2cm. Conclusions Intraoperative FSA allows resection of suspicious or positive margins at the time of lumpectomy and results in low rates of local recurrence and re-excision. The low local recurrence rate reported here is comparable to those reported with other margin assessment techniques.  相似文献   
56.
一阶导数差示脉冲极谱法的建立及在药物分析中的应用   总被引:11,自引:0,他引:11  
梁云爱  张天民 《药学学报》1992,27(2):135-138
本文研究了一阶导数差示脉冲极谱法,并将其运用于扑尔敏、氟哌啶醇、维生素B6及其制剂的定量分析中。方法简便、快速、灵敏、结果准确。  相似文献   
57.
Karkouti  K  Beattie  WS  Dattilo  KM  McCluskey  SA  Ghannam  M  Hamdy  A  Fedorko  L  Yau  TM 《Journal canadien d'anesthésie》2005,52(1):A64-A64
Canadian Journal of Anesthesia/Journal canadien d'anesthésie -  相似文献   
58.
59.
Summary: Oral ofloxacin has been successfully used in our centres for the primary treatment of peritonitis complicating continous ambulatory peritoneal dialysis (CAPD). In view of the progressive rise in the resistance rate to ofloxacin among peritoneal bacterial isolates, a study was conducted to determine if oral ofloxacin remains a viable first line treatment for CAPD peritonitis in our centres and if the result can be improved by changing from an oral to an intraperitoneal (i.p.) route. In patients on three 2 L daily CAPD exchanges, ofloxacin given at the i.p. dosage of 200 mg loading followed by 25 mg/L of peritoneal dialysate achieved overnight trough peritoneal levels which are at least four times the minimal 90% inhibitory concentration (MIC90) of most bacterial pathogens without significant accumulation in the systemic circulation. This i.p. dosage was therefore chosen for the clinical study and the result was compared to that using ofloxacin given in the oral dosage of 400 mg loading followed by 300 mg once daily as maintenance. of all the recruited episodes, 35 were eligible for analysis. the overall primary cure rate including primary failures and relapses was 55.6% (10/18) in the oral treatment group and 70.6% (12/17) in the i.p. treatment group. the corresponding figures for gram positive bacterial (g +) infections were 36.4% and 50%, for gram negative bacterial (g -) infections were 66.7 and 80% and for culture negative infections were 75 and 80%. In culture positive cases, all treatment failures were due to resistant infections which were observed in 42.3% of all bacterial isolates, 47.1% of g + isolates and 33.3% of g - isolates. Due to the high background level of bacterial resistance among our CAPD population, ofloxacin monotherapy given either by the oral or the i.p. route can no longer be recommended for the primary treatment of CAPD peritonitis.  相似文献   
60.
Quality systems and total process control in blood banking   总被引:3,自引:0,他引:3  
Blood banking has dramatically changed in the past few years. Is the old business hierarchy and medical model for management still workable? How do we want to organize our work today for success in the future? Implementation of quality systems may seem overwhelmingly complex at this time to many blood banking establishments. However, by methodically adhering to the requirements of organization development described in this review, blood centers can achieve goals of quality improvement and TPC. The FDA and the pharmaceuticals and medical device industries have set the direction and provided guidance to blood establishments. The AABB, American Society for Quality Control, the American Society for Training and Development, and numerous other professional organizations can contribute information and materials. The FDA's document on quality assurance and the CFR are the basic texts guiding the approach presented in this paper. The organization's structure and processes may need to be reengineered to meet the requirements of a culture based on quality and process control.  相似文献   
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