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91.
Twenty patients with major depressive disorder were studied with evoked potential (EP) topographic mapping after receiving placebo, imipramine, or amoxapine for 2 days in a random-assignment, double-blind design. Patients performed the Continuous Performance Test (CPT), a visual vigilance test. The stimuli were the digits 0-9, with 0 a target to be responded to with a button press. EPs were recorded from 32 channels and were averaged separately for detected and undetected targets and for false positives and correctly identified nontargets (no button press). Twenty-one normal controls were also tested. Amoxapine enhanced N120 amplitude in midline parietal and right parietal cortex where selective attention effects have been found to be greatest in studies of normal controls. Both amoxapine and imipramine enhanced differences in P200 between target and nontarget stimuli in comparison to placebo, with amoxapine differences again being greatest over midline parietal locations. CPT performance was significantly better on amoxapine than placebo. 相似文献
92.
93.
A definition and systems view of anaerobic capacity 总被引:3,自引:0,他引:3
Simon Green 《European journal of applied physiology》1994,69(2):168-173
The purpose of this paper is both to define terms used in exercise physiology, i.e. anaerobic capacity, anaerobic work capacity and anaerobic potential, and develop a systems perspective of anaerobic capacity. Philosophical argument is used to support the proposed definitions and systems view, which is an approach to assist in the universal acceptance of such terms amongst scientific investigators, coaches and athletes, and provide a focus on physiological mechanisms associated with anaerobic capacity which may be the subject of future investigation. 相似文献
94.
Brandon JC; Teplick SK; Haskin PH; Sammon JK; Muhr WF; Hofmann AF; Gambescia RA; Zitomer N 《Radiology》1988,166(3):665-667
The authors describe their experience with methyl tertiary butyl ether (MTBE) in a larger series of patients than previously reported in order to acquaint physicians with both its effectiveness for dissolution of common bile duct calculi and the limitations of its use. Ten patients with 13 biliary calculi underwent percutaneous stone dissolution treatment with the experimental cholesterol solvent, MTBE. Three stones completely dissolved within 30 minutes, seven were reduced in size, and three were visibly unaffected. All stones not completely dissolved were easily extracted by means of a stone basket except for one in a patient taken to surgery. Although MTBE perfusion is an effective technique for management of biliary calculi, practitioners should be aware that its use is quite time consuming and its odor difficult to control. 相似文献
95.
96.
97.
B. H. Green J. R. M. Copeland M. E. Dewey V. Sharma I. A. Davidson 《International journal of geriatric psychiatry》1994,9(10):789-795
The Liverpool Continuing Health in the Community Study has followed up 1070 elderly community subjects over 6 years. In the first year 123 subjects had case-level depression. Three years later 49 (39.8%) of the previously depressed were recovered, 33 (26.8%) were depressed, 16 (13%) were not available for interview and 25 (20.3%) were dead. This study looks at factors associated with the 3-year outcome of patients who were depressed at year 0. Two outcome groups that were compared were a recovered depression group and a recurrent/persistent depression group. The factors that were significantly associated with a recurrence of depression (or persistent depression) at year 3 were bereavement of a close figure in the 6 months before interview, loneliness and life dissatisfaction at year 3. A variety of traditional risk factors for depression (including age, marital status, physical ill-health and incapacity) failed to attain significance in predicting recurrent or persistent depression. When combined, both recovered and recurrently depressed groups at year 3 had significantly higher levels of pain and a higher number of serious upsets in the past 6 months and 6 weeks compared to a compared to a control group. The depressed at year 0 were more likely to have entered more dependent forms of accommodation by year 3. 相似文献
98.
S F Gardner J A Green E M Bednarczyk L Farnett F Miraldi 《American journal of hospital pharmacy》1992,49(6):1499-1506
The basics of positron emission tomography (PET) are presented, including the physics, instrumentation, and radiopharmaceuticals involved; the clinical and research applications; and the cost. In PET, organic molecules labeled with positron-emitting radionuclides are injected or inhaled, and the high-energy photons produced by annihilation events are detected by paired, integrated crystal detectors. A computer uses the lines of origin of these photons to reconstruct a three-dimensional map of a functioning organ system. The positron-emitting radionuclides most often used are carbon 11, oxygen 15, nitrogen 13, fluorine 18, and rubidium 82. PET imaging centers usually consist of a cyclotron facility, a radiochemistry facility, a PET scanner, and computers for image reconstruction. Radiopharmaceuticals used in PET may be divided into blood flow-imaging agents, metabolic imaging agents, and drug receptor-imaging agents. Although PET is still primarily a research tool, it has shown diagnostic potential in neurology, cardiology, and oncology. It has also shown promise as a tool for pharmacologic assessment, as in studies of the effects of the fluorinated quinolones on cerebral blood flow and glucose metabolism. PET may become important in drug development because it yields specific information relatively noninvasively. A single study carries an average break-even price tag of $1500-$2000; rigorous cost-benefit analyses should be conducted before society is asked to subsidize such costs. Positron emission tomography is a frontier technology for which valuable clinical applications are being discovered. Pharmacists can contribute enormously to PET applications and at the same time establish a unique subspecialty for the profession. 相似文献
99.
E I Traboulsi J C Silva M T Geraghty I H Maumenee D Valle W R Green 《American journal of ophthalmology》1992,113(3):269-280
The eyes of a 22-month-old girl with the cobalamin C complementation type of combined methylmalonic aciduria and homocystinuria were studied with light and electron microscopy. We observed vacuolization of the iris pigment epithelium, loss of photoreceptors in the central 3.3 mm of the macula, partial loss of the nerve fiber and ganglion cell layers between the fovea and optic disk, and partial optic atrophy. The sclera in the posterior pole was thickened with deposition of mucopolysaccharide. Electron microscopy showed inclusions containing fine granular material in conjunctival fibrocytes; corneal epithelium, keratocytes, and endothelial cells; iris pigment epithelium; ganglion cells; retinal pigment epithelium; and choroid and scleral fibrocytes. Enlarged mitochondria and clear vacuoles distended the corneal endothelial cells. We found evidence of possible lysosomal dysfunction and mucopolysaccharide storage, as well as a clinicopathologic correlation of the macular degeneration in this disease. 相似文献
100.
L. Valinsky S. Simhoni R. Bassal V. Agmon R. Yishai M. S. Green D. Cohen 《Clinical microbiology and infection》2006,12(10):968-973
A seroepidemiological study was performed to evaluate immunity to diphtheria and to determine the correlates of diphtheria toxoid antibody levels among children and adults in Israel. In total, 3,185 sera from an age-stratified sample of children and adults, obtained in 2000-2001, were tested for diphtheria toxoid antibodies by an in-house double-antigen ELISA. A level of or=0.1 IU/mL (full protection or seropositivity). Seronegativity increased significantly in subjects aged >50 years, reaching levels of 9.7%, 12.6% and 18.9% in the groups aged 50-54, 55-59 and >60 years, respectively (p 0.001), with rates of basic immunity following a similar pattern. Subjects born abroad had higher seronegativity rates than those born in Israel (7.7% vs. 4.9%; p 0.019). No difference in diphtheria toxoid antibody levels was found according to other demographical variables, such as gender, Jewish or Arab ethnicity, urban or rural settlements, and the subjects' place of residence. The level of immunity to diphtheria among children and adults in Israel was satisfactory, with the exception of individuals aged >50 years. The risk of diphtheria outbreaks is low, but sporadic cases may occur among individuals lacking basic immunity against the disease. 相似文献