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31.
Cat flea, Ctenocephalides felis felis (Bouché), feces are an essential part of larval nutrition under natural conditions. The mass values of adult flea feces can be measured by dissolving samples of flea feces in Drabkin's reagent, filtering, centrifuging, and measuring absorbance spectrophotometrically at 540 nm. Either flea feces or air-dried host blood can be used to generate the standard curve used to convert absorbance (optical density) values into mass values. Debris collected from flea-infested house cats averaged 23.02 mg debris per cat per h with an average of 10.41 mg flea feces per cat per h. Flea feces deposited in the environment serve as potential larval food. Adult flea feces comprised an average of 44.28% of the debris deposited from infested domestic house cats in this study. 相似文献
32.
E Patterson B J Scherlag R Lazzara 《The Journal of pharmacology and experimental therapeutics》1992,262(1):375-382
The electrophysiologic actions of the Class III antiarrhythmic drug, clofilium, and the Class IB antiarrhythmic drug, lidocaine, were examined in ischemically injured canine epicardium, 4 days after coronary artery occlusion. Experiments were performed utilizing 1) composite electrode recordings from the intact heart in the anesthetized dog and 2) intracellular and extracellular recordings from superfused canine epicardium. In intact hearts, both clofilium (2 mg/kg i.v.) and lidocaine (6 mg/kg i.v.) increased refractoriness (188 +/- 16 to 331 +/- 39 and 288 +/- 18 msec, respectively, P less than .01), and produced tachycardia-dependent conduction disorders in ischemically injured epicardium. For both drugs, slowing the sinus heart rate with vagus nerve stimulation (32 +/- 6/min) returned activation delays to predrug values. Unlike lidocaine, clofilium failed to increase maximal activation delays in ischemically injured epicardium preceding conduction block (116 +/- 14 msec vs. 71 +/- 7 msec and 147 +/- 16 msec for clofilium and lidocaine, respectively, P less than .01 for both drugs). In superfused epicardium, both clofilium (3 x 10(-7) M) and lidocaine (4 mg/l) prolonged refractoriness in ischemically injured epicardium (175 +/- 16 predrug vs. 273 +/- 33 msec, P less than .01) and (181 +/- 3 predrug vs. 216 +/- 10 msec, P less than .01), respectively, whereas only lidocaine reduced Vmax and prolonged local conduction times in the same tissue. The results demonstrate that 1) lidocaine increases refractoriness in ischemically injured tissue via a decrease in Vmax and conduction velocity and 2) clofilium increases refractoriness in ischemically injured tissue without altering action potential duration, Vmax or conduction velocity.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
33.
Inpatient depression in persons with burns. 总被引:5,自引:0,他引:5
J T Ptacek David R Patterson David M Heimbach 《The Journal of burn care & rehabilitation》2002,23(1):1-9
In this investigation the authors collected data regarding trait anxiety, well-being, and depression from 209 men and women who had been screened for prior psychiatric diagnosis and treated in an acute-care setting for burn injuries. Well-being was measured in reference to the month before the burn injury, whereas level of depression was self-rated by patients within 2 days of hospitalization, 5 days later, and 5 days after that. Ratings of depression were also obtained 1 month after hospital discharge. Results indicated that few patients rated their depression as severe at any point in time. Depression scores decreased significantly across the hospitalization period and were correlated with burn size, trait anxiety, and well-being. Depression ratings after discharge were significantly related to depression scores obtained at the end of the inpatient phase of the study. Although most patients did not report experiencing severe levels of depression, the stability of scores across time suggests the usefulness of early screening procedures. Catching such problems early may head off longer-term difficulties. 相似文献
34.
This case report describes the ophthalmic findings in a child with the linear naevus syndrome. The patient was referred by the Department of Paediatric Neurology with 'unilateral papilloedema'. This was thought to be a form of pseudopapilloedema, a finding that has not been previously described in this syndrome. 相似文献
35.
Cyclosporine nephrotoxicity in lung transplant recipients. 总被引:3,自引:0,他引:3
End-stage lung disease has been treated successfully by lung transplantation (LTXP) at our institution since 1983. We report on the renal function of 30 LTXP recipients who were followed for at least 6 months (mean, 39 months; range, 6-60 months). All patients received quadruple immunosuppressive therapy including cyclosporine A, with a trough serum level (RIA) between 150 and 250 ng/ml for the first 6 months between 125 and 150 mg/ml after 6 months. The mean serum creatinine (SeCr) increased from a baseline value of 75 +/- 3.5 to 182 +/- 13.9 microM at the end of the follow-up. The greatest change in SeCr occurred within the first 6 months post LTXP. Fifteen of 30 patients who were initially normotensive required at least one antihypertensive medication post LTXP. By the end of the follow-up, 9 patients had SeCr > 200 microM. Two patients in this institution have progressed to end-stage renal disease requiring dialytic therapy. CsA nephrotoxicity has emerged as a major source of morbidity in the lung transplant population. Nephrotoxicity occurs early, and there does not appear to be any trend toward reversibility despite a lowering of the dose. Renal parenchymal injury may be progressive, despite an apparent plateau of the SeCr in some patients. 相似文献
36.
Robert L Eisner Randolph E Patterson 《Journal of nuclear medicine》2007,48(11):1912-3; author reply 1913-4
37.
Steve Ramcharitar Mark S Patterson Robert J van Geuns Martin van der Ent Georgios Sianos Gijs M J M Welten Ron T van Domburg Patrick W Serruys 《Catheterization and cardiovascular interventions》2007,70(5):662-668
OBJECTIVES: To directly compare the magnetic navigation system (MNS) guidewires with conventional guidewires in branching tortuous phantoms with operators of varying MNS and percutaneous coronary intervention experience. BACKGROUND: Vessel tortuosity, angulation, and side branches remain limiting factors in coronary interventions. The MNS addresses these limitations by precisely directing the tip of a magnetised guidewire in vivo aided by two permanent adjustable external magnets. METHODS: Crossing and fluoroscopy times of six operators were evaluated in five tortuous Perspex(R) phantom vessels in three consecutive attempts. Standard guidewire (SG) usage was unrestricted. Two 2nd generation magnetic guidewires (MG) were used. Failure was noted if the cross was unsuccessful within 5 min. RESULTS: The magnetic navigation was vastly superior to SG techniques with increasingly tortuous phantoms. It dramatically decreased both the crossing and fluoroscopy times with maximal reduction from 201.7 +/- 111 to 36.4 +/- 13 sec, P < 0.001 and 204.7 +/- 24 to 47.2 +/- 19 sec, P < 0.001, respectively. The MNS had a 98.8% procedural success rate compared to 68% with SG techniques. Moreover it considerably limited the amount of wire usage from 5.5 to 1.3. Operators with prior MG experience performed significantly better than those without, except in the simplest phantom where the difference was nonsignificant (33.8 +/- 13 sec vs. 41.7 +/- 17 sec, P = 0.2). CONCLUSION: MNS significantly reduces both the crossing and fluoroscopy times in tortuous coronary phantom models achieving excellent success rates with dramatic reductions in guidewire usage. Operators with prior MNS experience had an advantage over the inexperienced. 相似文献
38.
Anthony P. Khalifah Ramsey R. Hachem Murali M. Chakinala Roger D. Yusen Aviva Aloush G. Alexander Patterson Thalachallour Mohanakumar Elbert P. Trulock Michael J. Walter 《American journal of transplantation》2005,5(8):2022-2030
Bronchiolitis obliterans syndrome (BOS) is a major cause of lung allograft dysfunction. Although previous studies have identified mild to severe rejection (grade>or=A2) as a risk factor for BOS, the role of minimal rejection (grade A1) remains unclear. To determine if A1 rejection by itself is a risk factor for BOS, we performed a retrospective cohort study on 228 adult lung transplant recipients over a 7-year period. Cohorts were defined by their most severe rejection episode (none, A1 only, and >or=A2) and analyzed for the subsequent development and progression of BOS using univariate and multivariate time-dependent Cox regression analysis. In the univariate model, the occurrence of isolated minimal rejection was a risk factor for all stages of BOS. Similarly, multivariate models that included HLA mismatch, cytomegalovirus pneumonitis, community acquired viral infection, underlying disease and type of transplant demonstrated that A1 rejection was a distinct risk factor for BOS. Furthermore, the associated risk with A1 rejection was slightly greater than the risk from >or=A2 and treatment of A1 rejection decreased the risk for subsequent BOS stage 1. We conclude that minimal rejection is associated with an increased risk for BOS development and progression that is comparable to A2 rejection. 相似文献
39.
A case of infectious mononucleosis presenting as bilateral acute dacryocystitis in a 7-year-old girl is reported. Acute dacryocystitis is uncommon in this age group, and an underlying systemic illness should be suspected particularly when it is bilateral. 相似文献
40.