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排序方式: 共有298条查询结果,搜索用时 15 毫秒
31.
32.
WE Gillies FRACO FRACS FRCS Anne MV Brooks MD PhD FRACO FRACS FRACP 《Clinical & experimental ophthalmology》1992,20(3):239-242
A method of combined cataract extraction with posterior chamber intraocular lens and trabeculectomy using separate incisions was tested in 44 operations on 38 patients. The mean preoperative intraocular pressure (IOP) of 28.1 ± 11.7 (range 12 to 56) mmHg on maximum medication was lowered to 13.9 ± 3.4 (9 to 23) mmHg at one year, with half the eyes still requiring topical medication. The IOP was 40 mmHg or more preoperatively in eight eyes and 20 mmHg or more in only two patients at one year. There were no rises in IOP above 20 mmHg in the early postoperative period (days 1 and 2). Visual acuity was 6/9 or better in 27 and 6/12 in three eyes. There was an expulsive haemorrhage in one case, rupture of the posterior capsule in two eyes and a choroidal detachment in one eye, but no flat anterior chambers. The two-incision method allowed placement of an intraocular lens with good postoperative pressure control. 相似文献
33.
Donohue JF Parsey MV Andrews C D'Urzo T Sharma S Schaefer K Claus R Baumgartner RA;Levalbuterol COPD Study Group 《COPD》2006,3(3):125-132
The efficacy and safety of nebulized levalbuterol in adults with chronic obstructive pulmonary disease (COPD) was evaluated in this multicenter, randomized, double-blind, parallel design study. Randomized subjects (n = 209) received levalbuterol (LEV) 0.63 mg or 1.25 mg, racemic albuterol (RAC) 2.5 mg, or placebo (PBO) TID for 6 weeks. Serial spirometry was completed in-clinic after study drug alone (weeks 0, 2, and 6) or in combination with ipratropium bromide 0.5 mg (week 4). The primary endpoint was the averaged FEV1 AUC(0-8 hrs) over weeks 0, 2 and 6 compared with placebo. Other endpoints included rescue medication use, safety parameters, COPD exacerbations, and global evaluations. All active treatments demonstrated improvements in the percent change in FEV1 AUC(0-8 hrs) over the double-blind period and at each visit vs PBO (p < 0.05). Rescue medication use vs. baseline (doses/day) changed over time: PBO +0.38 +/- 3.3; LEV 0.63 mg +0.07 +/- 3.3; LEV 1.25 mg -0.84 +/- 3.8 (p = 0.02 vs. RAC); RAC +0.97 +/- 2.5. The overall rate of adverse events was PBO 56.4%, LEV 0.63 mg 56.6%, LEV 1.25 mg 67.3%, and RAC 65.4%. Protocol-defined COPD exacerbations occurred in all groups (PBO 12.7%, LEV 0.63 mg 11.3%; LEV 1.25 mg 18.4%; RAC 21.2%). Withdrawals due to COPD exacerbations were significantly higher in the RAC group compared with PBO (PBO 0%; LEV 0.63 mg 1.9%; LEV 1.25 mg 4.1%; RAC 9.6% p = 0.01 vs. PBO). In this study, levalbuterol treatment in subjects with COPD was generally well tolerated, produced significant bronchodilation compared with PBO, and improved clinical control of COPD as evidenced by reductions in rescue medication use compared with PBO and/or RAC. 相似文献
34.
A comparison of levalbuterol with racemic albuterol in the treatment of acute severe asthma exacerbations in adults 总被引:7,自引:0,他引:7
Nowak R Emerman C Hanrahan JP Parsey MV Hanania NA Claus R Schaefer K Baumgartner RA;XOPENEX Acute Severe Asthma Study Group 《The American journal of emergency medicine》2006,24(3):259-267
This multicenter, randomized, double-blind trial compared nebulized levalbuterol (Lev) and racemic albuterol (Rac) in the treatment of acute asthma. METHODS: Adults with acute asthma exacerbations (FEV(1) 20%-55% predicted) received prednisone and either Lev (1.25 mg, n = 315) or Rac (2.5 mg, n = 312). Nebulized treatments were administered every 20 minutes in the first hour, then every 40 minutes for 3 additional doses, then as necessary for up to 24 hours. The primary end point was time to meet discharge criteria. Secondary end points included changes in lung function and hospitalization rates. A subset of 160 patients had plasma (S)-albuterol concentrations determined at study entry. RESULTS: Time to meet discharge criteria did not differ between the 2 treatments. FEV(1) improvement was greater following Lev compared with Rac, both after dose 1 and cumulatively over the entire treatment period (dose 1 in intent to treat [ITT] group: Lev 0.50 +/- 0.43 L, Rac 0.43 +/- 0.37 L; P = .02), particularly among the 60% of patients not on recent steroid therapy (dose 1: Lev 0.58 +/- 0.47 L, Rac 0.44 +/- 0.37 L; P < .01), and patients whose entry (S)-albuterol concentrations were in the highest quartile of those measured. A small and similar proportion of Lev-treated (7.0%) and Rac-treated (9.3%) patients required hospitalization (P = .28). Among patients not on steroids, fewer Lev- than Rac-treated patients required admission (3.8% vs 9.3%, P = .03), as was also the case for patients with high plasma (S)-albuterol concentrations. Asthma relapses (5% in 30 days) were lower than in previous reports and did not differ between groups. CONCLUSIONS: This study suggests that early, regular nebulized beta(2)-agonist and systemic corticosteroid therapy may reduce hospitalization and relapse rates in patients with acute severe asthma. Lev was well tolerated and compared favorably with Rac in improving airway function, particularly in those who were not on inhaled or oral corticosteroids and in those who had high plasma (S)-albuterol concentrations at presentation. 相似文献
35.
MV Pravin Charles Joshy M Easow Noyal M Joseph M Ravishankar Shailesh Kumar Umadevi Sivaraman 《The Australasian medical journal》2013,6(9):430-434
Background
Ventilator-associated pneumonia (VAP) is a common type of nosocomial pneumonia encountered in intensive care units. There are several aetiological agents which make treatment challenging. Improper antibiotic treatment of ventilated patients may lead to the emergence of multidrug resistant (MDR) pathogens.Method
A prospective study was performed over a period of 20 months. Our study had two arms: the first, ‘Incidence and risk factors of VAP in a tertiary care hospital’ was the subject of an earlier publication; we therefore present the second investigative arm in this work. The aetiological agents of patients on mechanical ventilation (MV) were identified by standard bacteriological method. The susceptibility pattern was evaluated by Kirby-Bauer disc diffusion method. Extended spectrum beta lactamase (ESBL) testing was performed by combination disc method, and metallo-beta lactamase (MBL) testing was performed by EDTA disk synergy test (EDS).Results
Late-onset VAP was associated with Pseudomonas aeruginosa, Klebsiella pneumoniae and Escherichia coli, while early-onset VAP was commonly caused by members of Enterobacteriaceae, Candida albicans and Staphylococcus aureus. 72.2 per cent of VAP patients had monomicrobial and 27.8 per cent had polymicrobial infection. Out of the 24 isolates obtained from patients with VAP, seven (29.2 per cent) were MDR pathogens. ESBL and MBL production was detected in 40 per cent and 20 per cent of Klebsiella pneumoniae isolated in our study. Around 50 per cent of isolates associated with late-onset VAP were MDR, while 22.2 per cent isolates obtained from patients with earlyonset VAP were MDR.Conclusion
VAP is a nosocomial pneumonia that is common among ventilated patients. The aetiological agents vary from common organisms to MDR pathogens that are difficult to treat. A proper knowledge of MDR pathogens and early isolation followed by prevention of prolonged antibiotic therapy can reduce the mortality of late onset VAP. 相似文献36.
37.
38.
Neutrophil apoptosis in the lung after hemorrhage or endotoxemia: apoptosis and migration are independent of IL-1beta 总被引:13,自引:0,他引:13
Hemorrhage and endotoxemia are associated with neutrophil accumulation in the lungs and the development of acute inflammatory lung injury. Because alterations in the rate of apoptosis may affect the number and function of neutrophils in the lungs, we determined the percentage of neutrophils undergoing apoptosis in the lungs of control, hemorrhaged, or endotoxemic mice. In control mice, 18.5 +/- 1.2% of pulmonary neutrophils were apoptotic. The proportion of apoptotic neutrophils in the lungs was significantly decreased 1 h after hemorrhage (6.5 +/- 1.6%, P < 0.01 compared to control) or endotoxemia (7.0 +/- 0.9%, P < 0.01 compared to control). Between 1 and 24 h after endotoxemia or hemorrhage, the proportion of apoptotic neutrophils in the lung remained significantly depressed compared to that in control, unmanipulated mice. By 48 h, the proportion of apoptotic neutrophils returned to baseline levels in the lungs of hemorrhaged (21.4 +/- 1.4%) or endotoxemic (16.4 +/- 1. 6%) mice. Lung neutrophil IL-1beta mRNA was significantly increased from that of control mice [i.e., 0.12 +/- 0.06 relative absorbance units (RAU)] 1 h after hemorrhage (5.19 +/- 0.068 RAU, P < 0.05 compared to control) or endotoxemia (8.90 +/- 1.53 RAU, P < 0.01 compared to control). In IL-1beta-deficient mice, there was no significant difference in lung neutrophil apoptosis or neutrophil entry into the lung after hemorrhage or endotoxemia compared to wild-type mice. Our results show that apoptosis among lung neutrophils is decreased for more than 24 h after hemorrhage or endotoxemia. Although IL-1beta expression is increased in lung neutrophils under these conditions, IL-1beta is not responsible for either the influx of neutrophils into the lung or the reduction of apoptosis in neutrophil populations after hemorrhage or endotoxemia. 相似文献
39.
Hon YY; Fessing MY; Pui CH; Relling MV; Krynetski EY; Evans WE 《Human molecular genetics》1999,8(2):371-376
The molecular basis for the genetic polymorphism of thiopurine S -
methyltransferase (TPMT) has been estab-lished for Caucasians, but it
remains to be elucidated in African populations. In the current study, we
determined TPMT genotypes in a population of 248 African-Americans and
compared it with allele frequencies in 282 Caucasian Americans. TPMT
genotype was determined in all individuals with TPMT activity indicative of
a heterozygous genotype (</=10.1 U/ml pRBC, n = 23African- Americans, n
= 21 Caucasians) and a control group with TPMT activity indicative of a
homozygous wild-type genotype (>10.2 U/ml pRBC, n = 23
African-Americans, n = 21 Caucasians). No mutant alleles were found in the
high activity control groups. The overall mutant allele frequencies were
similar in African-Americans and Caucasians (4.6 and 3.7% of alleles,
respectively). However, while TPMT*3C was the most prevalent mutant allele
in African-Americans (52.2% of mutant alleles), it represented only 4.8% of
mutant alleles in Caucasians ( P < 0.001). In contrast, TPMT*3A and
TPMT*2 were less common in African-Americans (17.4 and 8.7% of mutant
alleles), whereas TPMT*3A was the most prevalent mutant allele in
Caucasians (85.7% of mutant alleles). A novel allele ( TPMT*8 ), containing
a single nucleotide transition (G644A), leading to an amino acid change at
codon 215 (Arg-->His), was found in one African-American with
intermediate activity. These data indicate that the same TPMT mutant
alleles are found in American black and white populations, but that the
predominant mutant alleles differ in these two ethnic groups.
相似文献
40.
R V Parsey M Slifstein D R Hwang A Abi-Dargham N Simpson O Mawlawi N N Guo R Van Heertum J J Mann M Laruelle 《Journal of cerebral blood flow and metabolism》2000,20(7):1111-1133
Serotonin 5-HT(1A) receptors are implicated in the pathophysiology of neuropsychiatric conditions. The goal of this study was to evaluate methods to derive 5-HT(1A) receptor parameters in the human brain with positron emission tomography (PET) and [carbonyl-(11)C]WAY 100635. Five healthy volunteer subjects were studied twice. Three methods of analysis were used to derive the binding potential (BP), and the specific to nonspecific equilibrium partition coefficient (k3/k4). Two methods, kinetic analysis based on a three compartment model and graphical analysis, used the arterial plasma time-activity curves as the input function to derive BP and k3/k4. A third method, the simplified reference tissue model (SRTM), derived the input function from uptake data of a region of reference, the cerebellum, and provided only k3/k4. All methods provided estimates of regional 5-HT(1A) receptor parameters that were highly correlated. Results were consistent with the known distribution of 5-HT(1A) receptors in the human brain. Compared with kinetic BP, graphical analysis slightly underestimated BP, and this phenomenon was mostly apparent in small size-high noise regions. Compared with kinetic k3/k4, the reference tissue method underestimated k3/k4 and the underestimation was apparent primarily in regions with high receptor density. Derivation of BP by both kinetic and graphical analysis was highly reliable, with an intraclass correlation coefficient (ICC) of 0.84 +/- 0.14 (mean +/- SD of 15 regions) and 0.84 +/- 0.19, respectively. In contrast, the reliability of k3/k4 was lower, with ICC of 0.53 +/- 0.28, 0.47 +/- 0.28, and 0.55 +/- 0.29 for kinetic, graphical, and reference tissue methods, respectively. In conclusion, derivation of BP by kinetic analysis using the arterial plasma input function appeared as the method of choice because of its higher test-retest reproducibility, lower vulnerability to experimental noise, and absence of bias. 相似文献