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131.
OBJECTIVE: The reported results of intracoronary stenting with Palmaz-Schatz stents using the low dose anticoagulation protocol have been encouraging and no stent thrombosis was observed. The effectiveness of such method extending to the use of other types of stents was therefore evaluated in this study. METHODS: All patients followed the anticoagulation protocol (heparin and warfarin) using non-heparin-coated stents. From September 1995, 92 patients received intracoronary stenting (69 men, 23 women, mean age 60.9 years). Altogether 117 stents were implanted in 99 target arteries and 106 lesions. RESULTS: A total of 50.4% of the stents were bare stents (stents without protective sheaths). Both coil stents and slotted tubular stents were used. Stenting was performed without the guidance of intravascular ultrasonography and high-pressure poststenting inflation was used in only 24.0% of patients with less than optimal angiographic results. The mean (+/- SD) coronary minimum luminal diameter changed from 0.63 +/- 0.39 mm to 3.12 +/- 0.48 mm immediately after stenting. Both stent thrombosis rate and femoral bleeding complication rate remained at 0%. Four bare stents could not be deployed in the first instance but without sequels. No morbidity nor mortality was recorded. The mean hospital stay remained at a mean of 4.5 days. All patients (100%) were followed up regularly. The mean (+/- SD) clinical follow-up period was 229 +/- 173 days. Clinical symptoms improved in all patients. CONCLUSIONS: These findings further support that the method is safe and stent thrombosis was not observed. Post-stenting recoil was more with coil stents. Dislodgment and potential risk of embolization could not be underestimated with bare stents. The restenosis rate between different types of stents remains to be determined. 相似文献
132.
133.
The PROSITE pattern Zinc_Finger_C2H2 was extended to permit the detection of all C2H2 zinc fingers and their parent proteins in the recently completed sequence of the yeast genome. Additionally, a new computer program was written that extracts other zinc binding motifs (non C2H2 'fingers'), overlapping with the classical zinc finger pattern, from the found set of yeast C2H2 fingers. The complete and correct detection of all fingers is a prerequisite for the classification of the yeast zinc finger proteins in functional terms. The detected 53 yeast C2H2 zinc finger proteins do not contain finger clusters with 10 or more repeats, as is frequently found in higher eukaryotes. Only three proteins contain four or more fingers in a cluster. Moreover, nearly all 27 yeast proteins with tandem arrays of two or three finger domains can be classified into nine subgroups with high sequence conservation in their finger clusters, in particular of their DNA recognition helices. These results and application of the recently elaborated finger/DNA recognition rules suggest that the yeast proteins belonging to the same subgroup may recognize identical or very similar DNA sites. 相似文献
134.
P Engler-Pinto J Gama-Rodrigues F Pinatel Lopasso A Castro Cordeiro HW Pinotti 《Canadian Metallurgical Quarterly》1995,50(6):320-325
This study is to analyze gastric emptying (GE) of 99mTc tagged solid meals in 43 gastric ulcer (GU), 16 duodenal ulcer (DU) patients, and 15 normal subjects. Diagnosis of active ulcers had been made through high gastrointestinal endoscopy. The patients with GU were divided into three groups according to Johnson's classification. Gastric contents were measured at 15 minute intervals over a period of 150 minutes, with the person standing in front of a gamma-counter. The GE curve was obtained from the mean percentile of radioactivity of all the groups measured at 15 minute intervals. Results were submitted to statistical analysis. Significant delay in GE in DU patients compared to normals, type II and Type III group. However, GE of type I GU was not statistically different from the DU group nor of types II and III GU, occupying an intermediate e position. 相似文献
135.
Mycophenolate mofetil (the morpholinoethyl ester of mycophenolic acid) inhibits de novo purine synthesis via the inhibition of inosine monophosphate dehydrogenase. Its selective lymphocyte antiproliferative effects involve both T and B cells, preventing antibody formation. Mycophenolate mofetil has immuno-suppressive effects alone, but is used most commonly in combination with other immunosuppressants. Mycophenolate mofetil, in combination with cyclosporin and corticosteroids, has been studied in large, randomised clinical trials involving nearly 1500 renal allograft transplant recipients. These trials demonstrated that mycophenolate mofetil is significantly more effective in reducing treatment failure and acute rejection episodes than placebo or azathioprine. Additionally, mycophenolate mofetil may be able to reduce the occurrence of chronic rejection. Mycophenolate mofetil is relatively well tolerated. The most common adverse effect reported is gastrointestinal intolerance; haematological aberrations have also been noted. The reversible cytostatic action of mycophenolate mofetil allows for dose adjustment or discontinuation, preventing serious toxicity or an overly suppressed immune system. Cytomegalovirus tissue invasive disease and the development of malignancies are concerns that merit evaluation in long term follow-up studies. Mycophenolate mofetil does not cause the adverse effects typically associated with other commercially available immunosuppressant medications such as nephrotoxicity, hepatotoxicity, hypertension, nervous system disturbances, electrolyte abnormalities, skin disorders, hyperglycaemia, hyperuricaemia, hypercholesterolaemia, lipid disorders and structural bone loss. Based on preliminary information, a positive benefit-risk ratio has been demonstrated with the use of mycophenolate mofetil in the prophylaxis of rejection in cadaveric renal allograft transplantation. Data from studies in other types of organ transplants are promising, but are too limited to draw clear conclusions. Long term follow-up studies are required to confirm these observations. Although mycophenolate mofetil is expensive, the beneficial effects on the reduction of rejection, treatment failure and related expenses suggest that it is most likely to be cost effective. 相似文献
136.
HW van Marwijk 《Canadian Metallurgical Quarterly》1997,28(2):69-75
The typical chronic splanchnic syndrome is characterized by upper abdominal pain usually provoked by a meal, the finding of an epigastric bruit and weight loss in conjunction with haemodynamically significant stenosis of two or more of the splanchnic arteries. Diagnosis of chronic splanchnic syndrome depends mainly on a strong clinical suspicion. Usually the classical triad is incomplete or absent. Therefore chronic splanchnic syndrome should be considered, in every patient with chronic abdominal discomfort, after exclusion of other more common causes of upper abdominal discomfort. Findings from nonvasive and invasive diagnostic tests support the presence of chronic splanchnic syndrome. However, until now, the diagnosis of chronic splanchnic syndrome has usually only been made retrospectively if all the symptoms disappeared after technically successful reconstructive surgery. A variety of surgical techniques has been advocated to repair the splanchnic arteries. The choice of the technique is usually based on the preference and experience of the surgeon. 相似文献
137.
TL Toth SG Baka LL Veeck HW Jones S Muasher SE Lanzendorf 《Canadian Metallurgical Quarterly》1994,61(5):891-894
OBJECTIVE: To determine the potential for in vitro maturation, fertilization, and cleavage after cryopreservation of immature, prophase I human oocytes. DESIGN: Immature oocytes obtained in excess of the number required by the patient were randomized and cryopreserved at the prophase I stage or cultured as control. After thawing and maturation in vitro, test and control oocytes were inseminated with husband's sperm and evaluated for fertilization and cleavage in vitro. SETTING: In vitro fertilization program. PATIENTS: Consenting patients undergoing controlled ovarian hyperstimulation for the purposes of IVF. MAIN OUTCOME MEASURES: Rates of maturation to metaphase II, fertilization, and cleavage were compared between control and cryopreserved oocytes. RESULTS: Upon thaw, 58.5% (72/123) of prophase I oocytes were viable. Control oocytes demonstrated a 74.8% (98/131) maturation rate to metaphase II, a 56.5% (52/92) fertilization rate, and an 11.5% (6/52) blastocyst rate. Cryopreserved oocytes showed a 83.3% (60/72) rate of maturation, a 57.7% (30/52) fertilization rate, and a 3.3% (1/30) blastocyst rate. No significant differences were noted between any of these parameters. CONCLUSIONS: These results demonstrate that prophase I oocytes from stimulated IVF cycles are able to survive cryopreservation and resume meiosis to achieve full nuclear maturation post-thaw. In addition, cryopreserved oocytes retain the same capacity for fertilization and development as control oocytes. 相似文献
138.
139.
A novel flow-injection (FIA) system, for the rapid and direct determination of both total ammonia (T[NH3]) and total carbon dioxide (T[CO2]) in clinical blood samples, has been developed. Samples were injected into a carrier stream of H2O, then emerged with a reagent stream, where the analyte was converted into a gaseous species and diffused across a PTFE gas-permeable membrane into an acceptor stream. The trapped NH3/CO2 in the acceptor was determined on line by a bulk acoustic wave (BAW) impedance sensor. At a through-put of 20 and 65 h(-1), the proposed system exhibited a linear frequency response up to 200 micromol l(-1) ammonium and 20 mmol l(-1) bicarbonate with a detection limit of 1.0 and 10 micromol l(-1), respectively. Results obtained for T(NH3) in serum and T(CO2) in plasma were in agreement with those obtained by the conventional glutamate dehydrogenase (GDH) method and gas-sensing electrode method, respectively. The effects of composition of acceptor stream, cell constant of conductivity electrode, sample volume, flow rate and potential interferents on the FIA signals were also discussed. 相似文献
140.
JR Stofan L DiPietro D Davis HW Kohl SN Blair 《Canadian Metallurgical Quarterly》1998,88(12):1807-1813
OBJECTIVES: This study examined cross sectionally the physical activity patterns associated with low, moderate, and high levels of cardiorespiratory fitness. METHODS: Physical activity was assessed by questionnaire in a clinic population of 13,444 men and 3972 women 20 to 87 years of age. Estimated energy expenditure (kcal.wk-1) and volume (min.wk-1) of reported activities were calculated among individuals at low, moderate, and high fitness levels (assessed by maximal exercise tests). RESULTS: Average leisure time energy expenditures of 525 to 1650 kcal.wk-1 for men and 420 to 1260 kcal.wk-1 for women were associated with moderate to high levels of fitness. These levels of energy expenditure can be achieved with a brisk walk of approximately 30 minutes on most days of the week. In fact, men in the moderate and high fitness categories walked between 130 and 138 min.wk-1, and women in these categories walked between 148 and 167 min.wk-1. CONCLUSIONS: Most individuals should be able to achieve these physical activity goals and thus attain a cardiorespiratory fitness level sufficient to result in substantial health benefits. 相似文献