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101.
Paulo Cezar Galv?o do Amaral Euler de Medeiros ázaro Filho Thales Delmondes Galv?o Ettinger Eric Junior Galeno Egydio José de Magalh?es Neto Fabrício Mascarenhas Edvaldo Fahel 《JSLS, Journal of the Society of Laparoendoscopic Surgeons》2006,10(3):355-358
BACKGROUND: Randomized studies demonstrate that laparoscopic appendectomy yields better results compared with open techniques. We sought to identify factors that determine an extended hospital stay among patients undergoing laparoscopic appendectomy. METHODS: This was a prospective study including 669 patients undergoing laparoscopic appendectomy. We analyzed variables that can predict the length of hospital stay. RESULTS: Of 669 patients undergoing laparoscopic appendectomy, 141 stayed in the hospital for > or = 5 days (Group 1), and 97 stayed in the hospital for < or = 1 day after surgery (Group 2). The univariate analysis demonstrated that fever (P<0.0001), nausea and vomiting (P=0.060), leukocytosis (P<0.0001), gangrened or perforated intraoperative appearance of the appendix (P<0.0001), and appendix position behind the ileocecal junction (P<0.001) were related to a longer hospital stay. The multivariate analysis through logistical regression showed that the factors independently and significantly associated with an extended hospital stay were presurgical fever, appendix position behind the ileocecal junction, and intraoperative gangrened or perforated appearance of the appendix. CONCLUSION: Fever, appearance, and position of the appendix are factors related to an extended hospital stay. 相似文献
102.
103.
Minimally Invasive Coronary Artery Bypass Grafting: A New Method Using an Anterior Mediastinotomy 总被引:2,自引:0,他引:2
M. Clive Robinson M.D. David R. Gross D.V.M. Ph.D. William Zeman M.D. Eric Stedje-Larsen M.D. 《Journal of cardiac surgery》1995,10(5):529-536
The benefit of internal mammary artery (IMA) grafting as a long-lasting intervention for coronary artery disease is well recognized. However, largely because they are less invasive, catheter based alternatives are frequently chosen, particularly to treat single or double vessel disease. To retain the advantages of the IMA graft, and to offset the invasiveness of conventional coronary artery bypass grafting, we developed a new minimally invasive method using an anterior mediastinotomy for treating left anterior descending (LAD) or right coronary artery disease, or both. Feasibility studies using 16 pigs and a human cadaver led to approval by the Institutional Review Board for use of this procedure to treat six patients (four men, two women; mean age, 63.8 ± 13.6 [SD] yrs) who granted informed consent. Pedicle dissection of the IMA, using video assisted thoracoscopy if necessary, was made through a 2-to 3-inch horizontal anterior mediastinotomy. The underlying LAD artery was grafted during femoral vessel cardiopulmonary bypass, with cooling to 30°C, induced ventricular fibrillation, and left ventricular venting if required. Transesophageal echocardiography performed after bypass showed that two patients maintained normal wall motion and four had improvement from the original impairment. One patient suffered a recurrence of angina 4 weeks after the procedure; recatheterization showed an acutely angled IMA, subsequently corrected by balloon angioplasty. The results of follow-up dobutamine echocardiographic stress tests were negative in all patients. With this minimally invasive approach, the procedure should provide the benefits of IMA grafting with shorter hospital stay, more rapid recovery, and less overall cost. 相似文献
104.
Summary Dozens of novel cysteine proteinases have been identified in positive single-stranded RNA viruses and, for the first time, in large double-stranded DNA viruses. The majority of these proteins are distantly related to papain or chymotrypsin and may be direct descendants of primordial proteolytic enzymes. Virus genome synthesis and expression, virion formation, virion entry into the host cell, as well as cellular architecture and functioning can be under the control of viral cysteine proteinases during infection. RNA virus proteinases mediate their liberation from giant multidomain precursors in which they tend to occupy conserved positions. These proteinases possess a narrow substrate specificity, can cleave in cis and in trans, and may also have additional, nonproteolytic functions. The mechanisms of catalysis, substrate recognition and RNA binding were highlighted by the recent analysis of the three-dimensional structure of the chymotrypsin-like cysteine proteinases of two RNA viruses. 相似文献
105.
Restriction fragment length polymorphisms (RFLPs) of peripheral leucocyte DNA in insulin-dependent diabetes mellitus (IDDM) patients and in controls were studied with Southern blot analysis. IDDM has been reportedly associated positively with the HLA-DR3 and-DR4 in Caucasians, with the HLA-DR3 and-DR9 in Chinese, and negatively with the HLA-DR2 in both Caucasians and Chinese, Using an HLA-DQβcDNA probe, an EcoRI 2.2 kb fragment is found associated with DR2 controls (r = 0.78, P=1×10~(-6)), but not with DR2 IDDM patients, their respective frequencies being significantly different (P=0.02). The authors also report here their new findings that the frequencies of the EcoRI3.0 kb and BamHI3.3 kb fragments are both decreased in the patient group (P=0.0032 and P=0.0018 respectively). This suggested certain kinds of mutation such as partial deletion or others in the IDDM patients might have caused the RFLP pattern change as compared to the normal DNA. RFLPs may provide valuable information in searching for the genetic basis of IDDM. 相似文献
106.
Gene delivery systems are designed to control the location of administered therapeutic genes within a patient's body. Successful in vivo gene transfer may require (i) the condensation of plasmid and its protection from nuclease degradation, (ii) cellular interaction and internalization of condensed plasmid, (iii) escape of plasmid from endosomes (if endocytosis is involved), and (iv) plasmid entry into cell nuclei. Expression plasmids encoding a therapeutic protein can be, for instance, complexed with cationic liposomes or micelles in order to achieve effective in vivo gene transfer. A thorough knowledge of pharmaceutics and drug delivery, bio-engineering, as well as cell and molecular biology is required to design optimal systems for gene therapy. This mini-review provides a critical discussion on cationic lipid-based gene delivery systems and their possible uses as pharmaceuticals. 相似文献
107.
Influence of Preparation Factors on the Sustained Release of Nifedipine from Eudragit RL/RS Microspheres 总被引:1,自引:0,他引:1
用乳剂—溶剂挥发法制备硝苯地平的丙烯酸树脂缓释微球。微球中药物的释放速度随丙烯酸树脂EudragitRL/RS比率的增加以及制备时搅拌速率的增加而增大,随内相聚合物浓度的增加及微球粒径的增加而减小,释药50%所需时间与微球粒径呈良好线性。微球的释药速率也随药物含量的增加(从4.2%到16.7%)而增大,并快于药物结晶的溶解速率,但药物含量达26.6%时,微球释药速率明显下降并低于药物结晶的溶解速率。用差热分析和X射线衍射分析证明,药物含量为4.2,9.4和16.7%的微球中药物完全是以非晶态分散的,而含药26.6%的微球中有药物结晶存在。不同微球释药低于70%时,释放方式均符合Higuchi时间平方根方程。 相似文献
108.
香菇多糖注射液对慢性乙型肝炎外周血单个核细胞膜IL—2受体表达的影响 总被引:5,自引:0,他引:5
万克青 《湖南医科大学学报》1998,23(1):90-92
The effects of lentinan on peripheral blood mononuclear cell (PBMC) expression of IL-2 receptor in patients with chronic hepatitis B in vitro and in vivo were studied. The expression percentage of IL-2 receptor in 44 patients with chronic hepatitis before treatment was 36.74 +/- 7.74, which was lower than healthy subjects, and was 48.92 +/- 3.79 after 2 months treatment of lentinan, which was approximated the normal control. PBMC from 30 patients with chronic hepatitis B were cultured in vitro with or without lentinan. The percentage of expression IL-2 receptor was 12.81 +/- 2.62 without lentinan and was 35.70 +/- 4.87 in the presence of lentinan. The concentration of lentinan stimulating expression of IL-2 receptor was between 0.2 to 200 g.ml-1. The results suggest that lentinan stimulates expression of IL-2 receptor on PBMC, which is associated with the therapeutic effectiveness of lentinan treatment. 相似文献
109.
Denise Haderski Sergey Nazarenko Chih-Min Cheng Anne Hiltner Eric Baer 《Macromolecular chemistry and physics.》1995,196(8):2545-2561
The crystallization behavior of coextruded microlayered sheets comprised of 657 alternating layers of polycarbonate (PC) and a miscible copolyester of mainly 1,4-cyclohexanedimethanol and terephthalic acid (KODAR) was investigated as a function of annealing time when the KODAR was crystallized isothermally from the glass at 195°C. Comparisons were made with crystallization of KODAR alone, and with crystallization of KODAR from melt blends with PC. The kinetics of crystallization and the morphology of the crystallized KODAR were characterized with differential scanning calorimetry, and by examination of thin sections microtomed from annealed specimens in the polarized light microscope and the transmission electron microscope. The growth rate of small, birefringent KODAR spherulites was non-linear, and was strongly affected by diffusion of PC into the KODAR layers. Diffusion of amorphous PC into the KODAR layers retarded nucleation and spherulite growth and decreased spherulite density. The effect became more pronounced as the KODAR layer thickness was reduced. Spherulities nucleated randomly throughout the KODAR layers in the PC/KODAR 20/80 (w/w) microlayer and grew rapidly to form a continuous layer of impinged spherulites. In contrast, spherulites in the PC/KODAR 40/60 and 60/40 microlayers nucleated and grew along the center of the KODAR layers where the KODAR concentration was highest. 相似文献
110.
白内障超声乳化吸出及囊袋内人工晶体植入术 总被引:1,自引:0,他引:1
为观察和评价超声乳化白内障吸出术的临床效果、特点、并发病及防治措施,对41 眼白内障施行超声乳化吸出术及小切口(6mm)囊袋内人工晶体植入术,并以同期的白内障患者41眼行现代囊外摘除及后房型人工晶体植入做对照。结果:术后6个月,视力≥1.0者占43.9%>0.8者占70.7≥0.5者占92.7%,均明显高于对照组(P<0.001),术后平均散光为1.04±0.81,1,低于对照组(P<0.01)。白内障超声乳化吸出并囊袋内人工晶体植入术的复明效果优于囊外摘除并后房型人工晶体植入术。 相似文献