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目的 比较不同溶剂法结晶纯化头孢菌素C钠盐收率和质量。方法 用HPLC、ESEM等检测方法检测头孢菌素C钠盐的纯度和晶型。结果 用无水乙醇、丙酮、异丙醇三种溶剂所得的头孢菌素C钠盐指标均达到国内厂家内控检测标准,超过国外同类产品指标;其中以丙酮结晶法收率较高,乙醇结晶法纯度高,晶型好。结论 丙酮结晶法成本较低,为厂家选择结晶工艺提供参考。  相似文献   
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维生素A干预对大鼠抗氧化能力及细胞膜流动性影响的研究   总被引:12,自引:0,他引:12  
韩磊  马爱国  张燕 《卫生研究》2004,33(4):450-452
目的 通过对大鼠补充不同剂量维生素A(VA)观察机体抗氧化能力及对红细胞膜流动性的影响 ,了解抗氧化活性的最佳剂量。方法 将Wistar大鼠随机分为 4组 ,分别为维生素A缺乏组 (VA1组 )补充1 1 4 3(VA2组 )、4 2 86 (VA3组 )和 1 4 2 86 μgRE·kg- 1 ·d- 1 (VA4组 )维生素A三个剂量组。测定各组大鼠血浆VA含量、SOD、MDA和GSH Px的含量和活性 ,用荧光偏振度P值和微粘度 η值评价红细胞膜的流动性。 结果 各组血浆中VA水平随补充剂量的增加而增加。血浆中SOD、GSH -Px和MDA的结果显示 ,补充剂量为VA2、VA3组SOD的水平较VA缺乏组和VA4组明显偏低 (P <0 0 1 )。VA3组的MDA较其它 3个剂量组明显下降 (P <0 0 1 )。VA4组的SOD、MDA含量明显高于其它三个剂量组 (P <0 0 1 )。VA3组血浆中GSH -Px的活性明显升高 ,P <0 0 1。细胞膜流动性的结果显示 :VA3组P值最小 (P <0 0 1 ) ;VA4组P值明显增高 (P<0 0 1 )。微粘度 η在VA3组与VA缺乏组和VA2组之间未见明显差异 ,与VA4组相比明显下降 (P <0 0 1 )。结论 维生素A补充剂量为 4 2 86 μgRE·kg- 1 ·d- 1 时 ,能够发挥较好抗氧化作用 ,红细胞膜的流动性明显增加 ,过量摄入维生素A可造成机体的中毒反应 ,增加机体的氧化损伤  相似文献   
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Objectives: To determine the quality of life (QOL) after stapes surgery and whether audiological parameters for hearing correlate with specific QOL factors. Design: A retrospective cross‐sectional study. Setting: A tertiary referral centre. Participants: A series of 35 patients who underwent stapes surgery of which three were excluded because they were <18 years of age, chronically or mentally ill, or in a dependant relationship. Response rate was 93% (30/32). Nine were further excluded because they had revision or bilateral surgery, or missing data. Twenty‐one patients were included in this study. Main outcome measures: The Glasgow Benefit Inventory (GBI) was used to evaluate general QOL and the Hearing Disability and Handicap Scale (HDHS) was used as a disease‐specific measure. The Belfast Rule of Thumb and Glasgow Benefit Plot assessed hearing outcomes. Results: Operative success was 86% using the Belfast Rule of Thumb and 95% had closure of the air–bone gap to within 20 dB. 81.8% of patients reported a better overall QOL as surgery. Glasgow Benefit Inventory Social and GBI Physical scores correlated positively with the HDHS speech component (P < 0.05). The duration of hearing loss correlated inversely with the average HDHS score (P < 0.05). Conclusion: The majority of patients report a better QOL as undergoing stapes surgery. Speech impacts on people's physical and social QOL of patients. Quality of life tools, in addition to objective audiologic measurements can provide clinicians with patients’ subjective perspective that helps guide clinical decision‐making and counselling.  相似文献   
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OBJECTIVE: To evaluate the feasibility and potential benefits of hand-assisted laparoscopic surgery with the HandPort System, a new device. SUMMARY BACKGROUND DATA: In hand-assisted laparoscopic surgery, the surgeon inserts a hand into the abdomen while pneumoperitoneum is maintained. The hand assists laparoscopic instruments and is helpful in complex laparoscopic cases. METHODS: A prospective nonrandomized study was initiated with the participation of 10 laparoscopic surgical centers. Surgeons were free to test the device in any situation where they expected a potential advantage over conventional laparoscopy. RESULTS: Sixty-eight patients were entered in the study. Operations included colorectal procedures (sigmoidectomy, right colectomy, resection rectopexy), splenectomy for splenomegaly, living-related donor nephrectomy, gastric banding for morbid obesity, partial gastrectomy, and various other procedures. Mean incision size for the HandPort was 7.4 cm. Most surgeons (78%) preferred to insert their nondominant hand into the abdomen. Pneumoperitoneum was generally maintained at 14 mmHg, and only one patient required conversion to open surgery as a result of an unmanageable air leak. Hand fatigue during surgery was noted in 20.6%. CONCLUSIONS: The hand-assisted technique appeared to be useful in minimally invasive colorectal surgery, splenectomy for splenomegaly, living-related donor nephrectomy, and procedures considered too complex for a laparoscopic approach. This approach provides excellent means to explore, to retract safely, and to apply immediate hemostasis when needed. Although the data presented here reflect the authors' initial experience, they compare favorably with series of similar procedures performed purely laparoscopically.  相似文献   
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The treatment of patent ductus arteriosus (PDA) has evolved over the years. We reviewed 231 non-premature children (group 1) undergoing surgical closure of a PDA between January 1985 and December 1997, and 30 children (group 2) undergoing transcatheter closure from May 1995 to December 1998. The median age and weight at operation in group 1 were 13 months (range, 0.5-174 months) and 9.5 kg (range, 1.9-49.7 kg), respectively. There was one intra-operative death (0.4%) secondary to hemorrhage. Immediate extubation was performed in 208 patients (90%). Intra-operative chest tube use decreased from 73.3% to 10% between the 1985-88 and 1996-97 periods (P < 0.001). Postoperative pneumothoraces occurred in 33/131 (25%) patients with only one patient (0.7%) requiring drainage. Eleven patients had complications including wound infection in four, vocal cord paralysis in three, and left pulmonary artery stenosis in one. The median length of stay (LOS) was 5 days (range, 2-43 days). Follow-up echocardiogram was performed in 146/230 patients (63%) and revealed a residual PDA in six (4%); two being re-ligated, two remaining clinically insignificant, and two spontaneously resolved at 7 and 28 months follow-up. The remaining 84 patients had no clinical signs of a residual PDA. In group 2, where a transcatheter coil occlusion technique was used, the median age and weight at procedure were 31 months (range, 9-320 months) and 14.9 kg (range, 9-69.7 kg), respectively. Vascular complications occurred in four patients (13.3%). One patient developed hemolysis and hemoglobinuria requiring hospital admission. Four patients required a second intervention. At the most recent echocardiographic assessment, four patients (13.3%) had a residual PDA.  相似文献   
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Abstract

Background: Corrected QT (QTc) prolongation is predictive of cardiovascular mortality in both the general and human immunodeficiency virus (HIV) populations. Objective: As part of the HIV-HEART study, we assessed the prevalence and risk factors of a prolonged QTc interval in patients with HIV infection. Methods: In this cross-sectional cohort study, 802 unselected HIV-infected patients were included. Data were analyzed by the use of gender-specific QTc categories (men abnormal at > 440 ms and women abnormal at >460 ms). Multiple variables related to infection and treatment were collected. Results were analyzed with a multivariable model. Results: The QTc interval was found to be prolonged in 154 patients (19.8%; 95% CI 17–23). The mean (±SD) QTc in men (n = 142) presenting with a prolonged QTc interval was 456 ± 16.3 ms (range 441–548 ms).The mean (±SD) QTc in women (n = 12) presenting with a prolonged QTc interval was 479 ± 9 ms (range 465–498 ms). In the multivariable model, female gender, diabetes mellitus, and arterial hypertension were associated with prolonged QTc. There were no parameters related to HIV independently associated with QT interval prolongation. In particular, no anti-HIV drug was associated with QTc prolongation. Conclusions: Our study demonstrated that in an HIV-infected population, QTc prolongation had a high prevalence of nearly 20% compared to the general population and was possibly influenced by common factors like gender, diabetes, and arterial hypertension.  相似文献   
70.
Established in 2003 by the Office of Rare Diseases Research (ORDR), in collaboration with several National Institutes of Health (NIH) Institutes/Centers, the Rare Diseases Clinical Research Network (RDCRN) consists of multiple clinical consortia conducting research in more than 200 rare diseases. The RDCRN supports longitudinal or natural history, pilot, Phase I, II, and III, case–control, cross-sectional, chart review, physician survey, bio-repository, and RDCRN Contact Registry (CR) studies. To date, there have been 24,684 participants enrolled on 120 studies from 446 sites worldwide. An additional 11,533 individuals participate in the CR. Through a central data management and coordinating center (DMCC), the RDCRN’s platform for the conduct of observational research encompasses electronic case report forms, federated databases, and an online CR for epidemiological and survey research. An ORDR-governed data repository (through dbGaP, a database for genotype and phenotype information from the National Library of Medicine) has been created. DMCC coordinates with ORDR to register and upload study data to dbGaP for data sharing with the scientific community. The platform provided by the RDCRN DMCC has supported 128 studies, six of which were successfully conducted through the online CR, with 2,352 individuals accrued and a median enrollment time of just 2 months. The RDCRN has built a powerful suite of web-based tools that provide for integration of federated and online database support that can accommodate a large number of rare diseases on a global scale. RDCRN studies have made important advances in the diagnosis and treatment of rare diseases.  相似文献   
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