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排序方式: 共有1121条查询结果,搜索用时 52 毫秒
991.
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994.
G H Wendel A O Maria F Mohamed S Dominguez L Scardapane O S Giordano E Guerreiro J A Guzman 《Pharmacological research》1999,40(4):339-344
Dehydroleucodine (DhL), a sesquiterpene lactone (SQL) of the guaianolide type isolated from Artemisia douglasiana Besser, shows a pharmacological cytoprotective effect and significantly prevents the formation of gastric and duodenal lesions induced by various necrotising agents in rodents. The effects of DhL, on two models of experimental colitis were examined. Colitis was produced in male Wistar rats by rectal instillation of 5 and 10% acetic acid, following the methods of Eliakim et al. and Le Duc et al., respectively. In mice colitis was produced by rectal instillation of 0.1 ml of 2,4,6-trinitrobenzene sulphonic acid (5 mg in 50% ethanol) (TNB) as previously described by Chin et al. In this study, the administration of DhL 40 mg kg(-1)(1 h before the induction of colitis) significantly decreased mucosal damage. This effect was consistent in both models. The protection provided by DhL was accompanied by significant decreases in diarrhoea and colon weight; and histologically normal mucosa without ulceration and mucus production were observed. This study shows that both TNB and acetic acid colitis can be pharmacologically controlled by DhL. Our results suggest that the protective activity of DhL in experimental colitis is mediated, at least in part, through the increase of glycoprotein synthesis, anti-inflammatory effect and inhibition of COX-2 induction, and by inhibiting the degranulation of cells containing monoamines. 相似文献
995.
Coating-techniques to improve the hemocompatibility of artificial devices used for extracorporeal circulation. 总被引:10,自引:0,他引:10
OBJECTIVE: Extracorporeal circulation procedures have been shown to induce complement and leukocyte activation, release of endotoxin and inflammatory mediators, including cytokines, nitric oxide, oxygen free radicals, and platelet activating factors. The contact between the blood and the various artificial surfaces of the extracorporeal system results in an unspecific post-perfusion syndrome. For diminishing these negative side effects several coating-techniques have been developed to create devices with improved hemocompatibility. METHODS: This review deals with the current knowledge of heparin-coated and otherwise surface-modified perfusion systems. The pathway how heparin-coated surfaces work is discussed and techniques for surface-coatings, both clinically introduced as well as newly developed are presented. RESULTS: Numerous clinical studies compared heparin-coated versus non-coated circuits. Heparin-bonded devices showed lessened humoral and cellular activation, in particular a reduced complement activation with a reduced inflammatory post-perfusion syndrome. Also platelet protection and more favorable post-operative lung function are of particular note. Recent clinical trials demonstrated shortened hospital stays, less drainage bleeding, and reduced cerebral complications using heparin-coated oxygenation systems. The diminished expression of the leukocyte adhesion molecules CD 11b/c in CBAS devices points to a decreased activation of neutrophils. In addition, one research group found a reduced production of oxygen radicals. Heparin-bonding minimizes oxygenator failure by a significant reduced pressure gradient across the oxygenator, probably caused by decreased fibrin and platelet deposition at the hollow fiber surfaces. A meta analysis examined the impact of heparin-bonded systems on clinical outcomes and resulting costs. Using heparin-bonded circuits led to total cost savings from US $1000 to 3000. Several authors demonstrated reduced blood loss and better clinical outcome by reduction of systemic heparinization and the employment of heparin-coated devices. CONCLUSION: Above and beyond the long-term applications, routine heart operations have also markedly begun to utilize heparin-coated devices. This trend will assuredly continue in the coming years and is an important step toward higher hemocompatibility of blood-contacting surfaces in the ECC device. Heparin-coatings are merely the beginning of improved hemocompatibility for all materials that come into contact with human blood or tissues. Intelligent materials with almost completely physiological surfaces will be at the surgeon's disposal within the next few years. 相似文献
996.
Otto Wendel 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》1905,76(2-3):290-292
Ohne Zusammenfassung 相似文献
997.
Axel Scherer Hans‐Jrg Wittsack Volkher Engelbrecht Stefan Schwarz Philip May Ludger Wilhelm Poll Jens Albrecht Koch Udo Wendel Ulrich Mdder 《Journal of magnetic resonance imaging : JMRI》2001,14(6):757-762
Glycogen storage disease type Ib is an autosomal recessive inherited metabolic disorder resulting from deficiency of the microsomal glucose-6-phosphatase enzyme system. Six patients (three of which were treated with granulocyte colony stimulating factor) suffering from this disease were examined using image guided localized proton magnetic resonance (MR) spectroscopy. The relative signal intensities of water and lipid protons of the lumbar spine were determined. Comparison was made with iliac crest biopsies in the glycogen storage disease type Ib patients and localized proton MR spectroscopic values of the lumbar spine obtained by thirteen healthy volunteers. The data demonstrate for the first time that hypercellularity and myeloid hyperplasia in subjects with glycogen storage disease type Ib due to functionally impaired leucocytes results in a strongly increased water proton signal with a very low or absent lipid signal in localized proton MR spectroscopy. Upon granulocyte colony stimulating factor treatment, the water proton signal in the lumbar spine is not further augmented. 相似文献
998.
BACKGROUND: The significance of plasma L-alloisoleucine, which is derived from L-isoleucine in vivo, for diagnosis of maple syrup urine disease (MSUD) was examined. METHODS: Branched-chain L-amino acids were measured by automatic amino acid analysis. RESULTS: Alloisoleucine reference values in plasma were established in healthy adults [1.9 +/- 0.6 micromol/L (mean +/- SD); n = 35], children 3-11 years (1.6 +/- 0.4 micromol/L; n = 17), and infants <3 years (1.3 +/- 0.5 micromol/L; n = 37). The effect of dietary isoleucine was assessed in oral loading tests. In controls receiving 38 micromol (n = 6; low dose) and 1527 micromol (n = 3; high dose) of L-isoleucine per kilogram of body weight, peak increases of plasma isoleucine were 78 +/- 24 and 1763 +/- 133 micromol/L, respectively; the peak increase of alloisoleucine, however, was negligible for low-dose (<0.3 micromol/L) and minor for high-dose (5. 5 +/- 2.1 micromol/L) load. In patients with diabetes mellitus, ketotic hypoglycemia, phenylketonuria, and obligate heterozygous parents of MSUD patients, alloisoleucine was not significantly different from healthy subjects. Therefore, a plasma concentration of 5 micromol/L was used as a cutoff value. In patients with classical MSUD (n = 7), alloisoleucine was beyond the cutoff value in 2451 of 2453 unselected samples. In patients with variant MSUD (n = 9), alloisoleucine was >5 micromol/L in all samples taken for establishment of diagnosis and in 94% of the samples taken for treatment control (n = 624). With the other branched-chain amino acids, the frequency of diagnostically significant increases was <45%. CONCLUSIONS: The present findings indicate that plasma L-alloisoleucine above the cutoff value of 5 micromol/L is the most specific and most sensitive diagnostic marker for all forms of MSUD. 相似文献
999.
Katherine Croft Patricia J. Mattingly Patrick Bosse R. Wendel Naumann 《Journal of minimally invasive gynecology》2017,24(1):62-66
Study Objective
To determine whether educating surgeons about their controllable instrumentation costs by providing cost data on total laparoscopic hysterectomy (LH) would reduce the cost of this procedure.Design
Prospective cohort study (Canadian Task Force classification III).Setting
Academic-affiliated community hospital.Patients
Patients who underwent LH between April 2014 and March 2015 with surgeons who performed at least 10 LHs during that time period, along with a second group who underwent LH with the same cohort of surgeons between July 2015 and September 2015.Intervention
The cost of LH was calculated for all surgeons who performed more than 10 LHs between April 2014 and March 2015. Itemized cost data were collected. The individual costs, as well as a summary of the data, were shared with all of the physicians to highlight areas of potential cost savings. The costs were then measured for 3 months after the educational intervention (July–September 2015) to gauge the impact of physician cost education.Measurements and Main Results
Thirteen surgeons met the criteria for inclusion in this analysis. Together, they performed 271 hysterectomies, with an average instrumentation cost of $1539.47 ± $294.16 and an average operating room time of 178 ± 26 minutes. Bipolar instrument choice represented 37% of the baseline costs, followed by 10% for trocar, 9% for cuff closure, and 8% for uterine manipulator. This same group of surgeons performed a total of 69 hysterectomies in the 3-month follow-up period of July–September 2015, with an average instrumentation cost of $1282.62 ± $235.03 and an average operating room time of 163 ± 50 minutes. There was statistically significant cost reduction of $256.85 ± $190.69 (p = .022), with no significant change in operating room time. Bipolar instrument cost decreased significantly, by $130.02 ± $125.02 (p = .021), representing 51% of the total cost savings. Trocar, cuff closure, and uterine manipulator costs were not significant sources of cost savings on average, but did represent sources of cost savings for some surgeons individually.Conclusion
Given adequate education about the products available for use in their institution, surgeons make informed decisions regarding the choice of instrumentation, allowing them to directly impact the cost of total LH, resulting in cost savings. 相似文献1000.
Jubilee Brown R. Wendel Naumann Michael J. Seckl Julian Schink 《Gynecologic oncology》2017,144(1):200-207
Significant improvements in treatment and the understanding of gestational trophoblastic neoplasia have occurred in the last 15 years. These diseases are almost always curable, and refractory patients have more options for salvage therapy. Recent improvements in the understanding of epidemiology, diagnosis, and cell biology have resulted in changes in staging, advances in treatment options, and opportunities for fertility preservation. 相似文献