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排序方式: 共有720条查询结果,搜索用时 15 毫秒
1.
M. Perwaiz Iqbal M. Khalid Ashfaq Sarfaraz K. Niazi M. Mahboobali Khalid N. Khawaja 《Biopharmaceutics & drug disposition》1994,15(2):173-177
Pharmacokinetic parameters of two antifolates, trimethoprim and aditoprim, were studied in buffalo calves. The elimination half-life of aditoprim (6.14 h) was nearly twice as long as that of trimethoprim (3.08 h) and compares well with values observed in heifers. This longer half-life of aditoprim is a result of its much larger distribution volume (four to five times larger) because the clearance of aditoprim was about twice as high as that of trimethoprim. The longer half-life of aditoprim is expected to give a longer duration of in vivo bacteriostatic activity than that of trimethoprim. 相似文献
2.
Long H. Phan Michael J. Hickey Zahid B. M. Niazi Alastair G. Stewart 《Microsurgery》1994,15(10):703-707
Nitric oxide (NO), originally identified as the mediator of endothelial-dependent relaxation of vascular smooth muscle, is now known to also have cytotoxic effects under certain conditions. Thus, we have investigated the effects of inhibition of NO synthesis on ischemia/reperfusion injury in the rabbit rectus femoris muscle. Three and a half hours of ischemia and 24 hours of reperfusion resulted in a 56% loss of viability. In muscles receiving an infusion of the nitric oxide synthase inhibitor, L-NIO (30 μM), the loss of viability was reduced to 15%. Post-ischemic blood flow was increased in muscles receiving a saline infusion, whereas there was a marked decrease in blood flow for at least the first 60 minutes of reperfusion in muscles treated with L-NIO (30 μM). The increase in myeloperoxidase levels (indicative of neutrophil accumulation) following 24 hours of reperfusion was attenuated with L-NIO infusion by approximately 50% and the reperfusion-induced edema was also attenuated in L-NIO treated muscle. These findings suggest that endogenous NO production during ischemia/reperfusion injury may be deleterious to muscle survival. © 1994 Wiley-Liss, Inc. 相似文献
3.
Enrique E Pineda F Malek T Bartra J Basagaña M Tella R Castelló JV Alonso R de Mateo JA Cerdá-Trias T San Miguel-Moncín Mdel M Monzón S García M Palacios R Cisteró-Bahíma A 《The Journal of allergy and clinical immunology》2005,116(5):1073-1079
BACKGROUND: Food allergy may be life-threatening, and patients affected need to receive accurate diagnoses and treatment. Hazelnut has often been implicated as responsible for allergic reactions, and trace quantities can induce systemic reactions. OBJECTIVE: The aim of this study was to evaluate the efficacy and tolerance of sublingual immunotherapy with a standardized hazelnut extract in patients allergic to hazelnut. METHODS: This was a randomized, double-blind, placebo-controlled study. Inclusion criteria were a history of hazelnut allergy and positive skin prick test and double-blind placebo-controlled food challenge results. Patients were then randomly assigned into 2 treatment groups (hazelnut immunotherapy or placebo). Efficacy was assessed by double-blind, placebo-controlled food challenge after 8 to 12 weeks of treatment. Blood samples were drawn for measurement of specific IgE, IgG(4), and serum cytokines before and after treatment. RESULTS: Twenty-three patients were enrolled and divided into 2 treatment groups. Twenty-two patients reached the planned maximum dose at 4 days. Systemic reactions were observed in only 0.2% of the total doses administered. Mean hazelnut quantity provoking objective symptoms increased from 2.29 g to 11.56 g (P = .02; active group) versus 3.49 g to 4.14 g (placebo; NS). Moreover, almost 50% of patients who underwent active treatment reached the highest dose (20 g), but only 9% in the placebo. Laboratory data showed an increase in IgG(4) and IL-10 levels after immunotherapy in only the active group. CONCLUSION: Our data confirm significant increases in tolerance to hazelnut after sublingual immunotherapy as assessed by double-blind, placebo-controlled food challenge, and good tolerance to this treatment. 相似文献
4.
A. Chuan B. Jeyaratnam G. Iohom G. Shorten P. Lee S. Miglani K. Kwofie J. Szerb A. U. Niazi R. Jin T. Jen C. J. McCartney R. Ramlogan the Education in Regional Anaesthesia Collaboration Group 《Anaesthesia》2021,76(7):911-917
The learning curve for novices developing regional anaesthesia skills, such as real-time ultrasound-guided needle manipulation, may be affected by innate visuospatial ability, as this influences spatial cognition and motor co-ordination. We conducted a multinational randomised controlled trial to test if novices with low visuospatial ability would perform better at an ultrasound-guided needling task with deliberate practice training than with discovery learning. Visuospatial ability was evaluated using the mental rotations test-A. We recruited 140 medical students and randomly allocated them into low-ability control (discovery learning), low-ability intervention (received deliberate practice), high-ability control, and high-ability intervention groups. Primary outcome was the time taken to complete the needling task, and there was no significant difference between groups: median (IQR [range]) low-ability control 125 s (69–237 [43–600 s]); low-ability intervention 163 s (116–276 [44–600 s]); high-ability control 130 s (80–210 [41–384 s]); and high-ability intervention 177 s (113–285 [43–547 s]), p = 0.06. No difference was found using the global rating scale: mean (95%CI) low-ability control 53% (95%CI 46–60%); low-ability intervention 61% (95%CI 53–68%); high-ability control 63% (95%CI 56–70%); and high-ability intervention 66% (95%CI 60–72%), p = 0.05. For overall procedure pass/fail, the low-ability control group pass rate of 42% (14/33) was significantly less than the other three groups: low-ability intervention 69% (25/36); high-ability control 68% (25/37); and high-ability intervention 85% (29/34) p = 0.003. Further research is required to determine the role of visuospatial ability screening in training for ultrasound-guided needle skills. 相似文献
5.
Background: Vitamin B12 deficiency after gastric surgery for obesity is due to a failure of separation of vitamin B12 from protein foodstuffs and to a failure of absorption of crystalline vitamin B12 in the presence of intrinsic factor. The purpose of this study was to determine which of four oral doses of crystalline vitamin
B12 was most effective in treating vitamin B12 deficiency in 102 patients. Methods and Results: At time of entry into the study, the patients had a serum vitamin B12 < 100 pmol L −1, were 29.9 ± 21.7 months post-op, were 37 ± 8 years old and had a body mass index of 30 ± 6 kg m−2. Eight (8%) had had a vertical banded gastroplasty and 94 (92%) a gastric bypass. For the first 3 months all patients received
350 μg per day of crystalline vitamin B12 and all increased their serum vitamin B12 levels to over 100 pmol L−1. The patients were then assigned to receive for a further 3 month period one of four oral doses of crystalline vitamin B12-100 μg, 250 μg, 350 μg and 600 μg. Serum vitamin B12 levels were greater than 150 pmol L−1 after 6 months in 83.3% of patients who received 100 μg; 92.3% of patients who received 250 μg; 94.7% after 350 μg and 95.2%
after 600 μg (p%0.525). Conclusion: At least 350 μg per day is the appropriate oral dose of crystalline vitamin B12 after gastric surgery for obesity to correct low serum vitamin B12 levels in 95% of patients. 相似文献
6.
Experience with endoluminal colonic wall stents for the management of large bowel obstruction for benign and malignant disease 总被引:4,自引:0,他引:4
Tamim WZ Ghellai A Counihan TC Swanson RS Colby JM Sweeney WB 《Archives of surgery (Chicago, Ill. : 1960)》2000,135(4):434-438
HYPOTHESIS: To assess the applicability and efficacy of endoluminal colonic wall stents (ECWSs) in the management of large bowel obstruction (LBO). DESIGN: Inception cohort study. SETTING: University-based tertiary medical center. PATIENTS: Eleven consecutive patients with LBO in the absence of peritonitis. INTERVENTION: Placement of ECWS under endoscopic and fluoroscopic guidance. MAIN OUTCOME MEASURES: The success rate in ECWS placement, the efficacy in decompressing the obstruction, and the patency rate of the ECWS. RESULTS: Successful placement of ECWSs was obtainable in 10 of 11 patients. Once placed, all 10 patients achieved immediate decompression of their LBO. Eight patients had malignant obstructions associated with distant spread of disease; 3 patients had diverticular disease. Among those with malignant obstruction, 6 patients had successful and lasting palliation without colostomy, 1 patient underwent 1-stage resection 1 month later with no evidence of obstruction, and 1 patient could not be stented so diversion was done. None of the patients with diverticular disease required diversion: 2 had complete bowel preparation followed by resection with primary anastomosis, whereas the third declined surgery. Four of the 10 patients required overlapping ECWSs to bridge the stricture. One patient required a second ECWS secondary to recurrence of obstruction after stent migration and has continued palliation of his stage 4 rectal cancer for the last 11 months. No other complications were encountered. CONCLUSIONS: Urgent surgery with colostomy for LBO was avoided in 10 of 11 patients because of successful placement of ECWSs. We believe that endoscopic colonic stenting is safe, effective, and lasting, and should be considered as initial nonoperative management in all patients seen with LBO in the absence of peritonitis. 相似文献
7.
Farideh Doroodgar Feizollah Niazi Sana Niazi Azad Sanginabadi Cyrus Alinia 《国际眼科杂志》2019,19(7):1089-1094
目的:评估可植入式Phakic角膜接触镜治疗稳定型圆锥角膜患者的疗效、安全性、稳定性和可预测性。
方法:共14例患者采用植入式Phakic角膜接触镜(IPCL)矫正屈光不正,测量了未矫正视力、最佳矫正视力、离焦曲线、对比敏感度、屈光度及可能的副作用。评估结果超过6mo。
结果:平均等效球镜度(SE)和散光在术后6mo末次检查时由术前-6.94±2.79 DS和-4.24±1.42 DC分别变为术后-0.23±0.43 DS和-1.05±0.49 DC。术前平均Snellen视力为0.18±0.10。6mo内未矫正视力和最佳矫正视力平均值分别为0.13±0.10和0.05±0.15。平均安全指数为1.11。所有眼视力均无降低,其中22眼视力提高超过1行。20眼(71.4%)屈光度在0.50 D以内,27眼(96.42%)在±1.00 D以内。术后1wk至6mo,屈光度变化为-0.23±0.43(范围: -1.00至+0.75)。6mo内角膜内皮细胞(ECL)丢失率小于5%。术后6mo眼压(IOP)为11.32±2.28 mmHg。
结论:Toric植入式Phakic角膜接触镜在矫正与稳定圆锥角膜相关的近视和近视散光方面具有有效性、安全性和可预测性。 相似文献
8.
Approach to Non‐Neutropenic Fever in Pediatric Oncology Patients—A Single Institution Study
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9.
Effect of narghile and cigarette smoking on newborn birthweight 总被引:1,自引:1,他引:0
Tamim H Yunis KA Chemaitelly H Alameh M Nassar AH;National Collaborative Perinatal Neonatal Network Beirut Lebanon 《BJOG : an international journal of obstetrics and gynaecology》2008,115(1):91-97
Objective To assess the effect of narghile smoking on the weight of newborns.
Design Historical retrospective cohort.
Setting Six major hospitals in Greater Beirut, Lebanon.
Population Consecutive singleton newborns delivered from August 2000 to August 2003.
Methods Obstetric and nursery charts were reviewed to obtain information about maternal and neonatal variables. Information concerning initiation of smoking, dose of smoking, smoking habits during pregnancy, and socio-demographic characteristics was collected through interviews with mothers.
Main outcome measures Low birthweight and newborn birthweight.
Results Exclusive narghile smokers constituted 4.4% (378/8592) of women. Multiparas were significantly more likely to smoke cigarettes and narghile. Mothers smoking narghile more than once per day were at 2.4 increased odds of having low birthweight infants compared with nonsmoking mothers (OR 2.4; 95% CI 1.2–5.0) after adjusting for confounding variables. No difference was noted between women smoking narghile in the first trimester and those initiating smoking in subsequent trimesters regarding low birthweight.
Conclusions Narghile smoking more than once per day increases the odds of low birthweight by a 2.4-fold compared with nonsmokers, although to a lesser extent than cigarette smoking. 相似文献
Design Historical retrospective cohort.
Setting Six major hospitals in Greater Beirut, Lebanon.
Population Consecutive singleton newborns delivered from August 2000 to August 2003.
Methods Obstetric and nursery charts were reviewed to obtain information about maternal and neonatal variables. Information concerning initiation of smoking, dose of smoking, smoking habits during pregnancy, and socio-demographic characteristics was collected through interviews with mothers.
Main outcome measures Low birthweight and newborn birthweight.
Results Exclusive narghile smokers constituted 4.4% (378/8592) of women. Multiparas were significantly more likely to smoke cigarettes and narghile. Mothers smoking narghile more than once per day were at 2.4 increased odds of having low birthweight infants compared with nonsmoking mothers (OR 2.4; 95% CI 1.2–5.0) after adjusting for confounding variables. No difference was noted between women smoking narghile in the first trimester and those initiating smoking in subsequent trimesters regarding low birthweight.
Conclusions Narghile smoking more than once per day increases the odds of low birthweight by a 2.4-fold compared with nonsmokers, although to a lesser extent than cigarette smoking. 相似文献
10.
Fernando Luiz de Melo Bernardi Henrique Barbosa Ribeiro Luis Nombela-Franco Enrico Cerrato Gabriel Maluenda Tamim Nazif Pedro Alves Lemos Matias Sztejfman Pablo Lamelas Dario Echeverri Marcelo Antonio Cartaxo Queiroga Lopes Fbio Sndoli de Brito Jr Alexandre A. Abizaid Jos A. Mangione Helene Eltchaninoff Lars Sndergaard Josep Rodes-Cabau 《Arquivos brasileiros de cardiologia》2022,118(6):1085
Background:Transcatheter aortic valve replacement (TAVR) is a worldwide adopted procedure with rapidly evolving practices. Regional and temporal variations are expected to be found.Objective:To compare TAVR practice in Latin America with that around the world and to assess its changes in Latin America from 2015 to 2020.Methods:A survey was applied to global TAVR centers between March and September 2015, and again to Latin-American centers between July 2019 and January 2020. The survey consisted of questions addressing: i) center’s general information; ii) pre-TAVR evaluation; iii) procedural techniques; iv) post-TAVR management; v) follow-up. Answers from the 2015 survey of Latin-American centers (LATAM15) were compared with those of other centers around the world (WORLD15) and with the 2020 updated Latin-American survey (LATAM20). A 5% level of significance was adopted for statistical analysis.Results:250 centers participated in the 2015 survey (LATAM15=29; WORLD15=221) and 46 in the LATAM20. Combined centers experience accounted for 73 707 procedures, with WORLD15 centers performing, on average, 6- and 3-times more procedures than LATAM15 and LATAM20 centers, respectively. LATAM centers performed less minimalistic TAVR than WORLD15 centers, but there was a significant increase in less invasive procedures after 5 years in Latin-American centers. For postprocedural care, a lower period of telemetry and maintenance of temporary pacing wire, along with less utilization of dual antiplatelet therapy was observed in LATAM20 centers.Conclusion:Despite still having a much lower number of procedures, many aspects of TAVR practice in Latin-American centers have evolved in recent years, followingthe trend observed in developed country centers. 相似文献