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91.
Summary  Surgical repair of enterocutaneous fistulae in Crohn’s disease may result in large skin defects of the anterior abdominal wall. We present a case in which a large defect was managed with reconstruction using a pedicled rectus abdominis mycocutaneous flap in a single procedure. The case highlights the technical challenge of such a case and the value of a joint surgical approach between plastic and colorectal services.  相似文献   
92.
This study investigated the applicability and utility of Megargee and Bohn's MMPI-based offender classification system in correctional mental health units (MHUs). Previous studies found that 11 MHU samples (n = 1723) had substantially more offenders classified in the more pathological MMPI types than did 21 samples (n = 5881) drawn from general male populations in US prisons. In this study of 63 severely disturbed felons, 43% belonged to the most pathological type (‘group How’). Comparing MHU patients with general offenders from the same IvfIvIPI types on staff ratings and case history variables, we found that the MHU patients were significantly poorer in adjustment. Within the MHU sample, there was no difference in case history variables or adjustment ratings between those in the most and least severe MMPI types. These findings differed from those of studies using less severely disturbed, more heterogeneous, MHU populations. It was concluded that, in settings in which the entire population is flagrantly disturbed, the MMPI-based system is more useful in screening potential admissions than it is in making meaningful distinctions among those already admitted.  相似文献   
93.
There is some controversy about the role of long-term potentiation (LTP) in spatial learning. The authors have found that triggering generalized kindled seizures with stimulation of the perforant path disrupts spatial learning in the Morris water maze but that kindling per se does not affect spatial learning. It is suggested that abnormal electrical activity induced by high-frequency stimulation of the perforant path may have been responsible for the disruption of spatial learning previously attributed to LTP saturation.  相似文献   
94.
Effects of alfentanil, preceded by lorazepam, on suppressionof haemodynamic and somatic responses to noxious stimuli wasstudied in patients undergoing CABG. Plasma concentration ofalfentanil, somatic and haemodynamic responses were measuredat loss of consciousness, tracheal intubation, sternotomy andduring multiple applications of electrocoagulation. Additionalalfentanil was administered i.v. to control unwanted responses.Study 1 (six patients): lorazepam 0.08 mg kg–1 by mouth1–2 h before operation, alfentanil priming infusion (60µg kg–1 min–1 for 10 min) followed by maintenanceinfusion (4.5 µg kg–1 min–1). With mean plasmaalfentanil 1178 (SEM 54) ng ml–1, two patients requiredsupplementary alfentanil to suppress somatic motor responses;one patient required nitroglycerin to control an increase inarterial pressure which was unresponsive to additional alfentanilfollowing sternotomy. Study 2 (13 patients): lorazepam 0.04mg kg–1 by mouth as premedication; one of three maintenanceinfusion rates of alfentanil: 5.4 (n=4), 6.6 (n=5), or 7.8 (n=4)µg kg–1 min–1, each preceded by a proportionalpriming infusion. With plasma alfentanil 2181 (62)ng ml–1,somatic motor responses requiring additional alfentanil occurredin nine patients; haemodynamic responses in four of seven patientstested could not be controlled by alfentanil. The highest plasmaconcentration of alfentanil to prevent response to a stimulusother than tracheal intubation was different between the twostudies (P<0.05). We conclude that alfentanil alone is insufficientto suppress haemodynamic and somatic motor responses to noxiousstimulation during CABG and that the role of premedication issignificant. *Department of Anesthesia, Bowman-Gray School of Medicine Winston-Salem,NC 27103, U.S.A. 2114 de Mayo Road, Del Mar, Ca. 92014, U.S.A.  相似文献   
95.
An Immunotoxicological Evaluation of 4,4'-Thiobis-(6-t-butyl-m77-cresol)in Female B6C3F1 Mice. 1. Body and Organ Weights, Hematology,Serum Chemistries, Bone Marrow Cellularity, and Hepatic MicrosomalParameters. MUNSON, A. E., WHITE, K. L., JR., BARNES, D. W.,MUS-GROVE, D. L., LYSY, H. H., AND HOLSAPPLE, M. P. (1988).Fundam. Appl. Toxicol. 10, 691–700. Adult female B6C3F1mice were gavaged with 4,4'-thiobis-(6-t-butyl-m-cresol) (TBBC)in corn oil at doses of 10, 100, or 200 mg/kg daily for 14 consecutivedays. There was no overt toxicity, as manifested by grosslyobservable behavioral changes, decreased growth rate over theexposure period, or mortality. There were also no marked effectson serum chemistries or hematology, with the exception of asignificant increase (41%) in the number of leukocytes at thehighest dose. Absolute differential counts indicated that significantincreases occurred in the number of lymphocytes (31%) and neutrophils(177%). Studies with bone marrow indicated a significant 30%increase in the number of cells/femur from animals treated withthe highest dose of TBBC. The number of macrophage progenitors(CFU-M)/femur was significantly increased by 28%, while thenumber of granulocyte-monocyte progenitors (CFU-GM)/femur wasnonsig-nificantly increased by 20% in the high dose animals.The weight of both the spleen and liver was increased in a dose-relatedfashion, although the histopathology of the spleen of TBBC-treatedmice was not different from control. The livers of mice receivingthe high dose showed mild focal hydropic degeneration, mildhepatitis, and a slight increase in the number of Kupffer cells.No other organs were affected. Liver microsomal protein andcytochrome P-450 levels were increased in a dose-related fashion.Enzyme activities of aminopyrine demethylase and aniline hydroxylase,but not arylhydrocarbon hydroxylase, were also increased ina dose-related fashion.  相似文献   
96.
The Hemopump Cardiac Assist System is a relatively new intraarterial, axial-flow circulatory assist device that offers temporary left ventricular support to patients in refractory cardiogenic shock, without requiring major surgery for insertion. Use of the Hemopump is associated with a low complication rate. Device-related morbidity is extremely rare. Because the Hemopump is safe for use in community hospitals, the number of patients supported by this device is expected to increase. In this report, we present general guidelines for the care of patients supported by the Hemopump. We describe techniques for the management of afterload reduction, supravalvular dislodgement, device malfunction, ventricular ectopy, intracardiac shunting, and inflow cannula obstruction.  相似文献   
97.
Mode and speed specificity of eccentric and concentric exercise training   总被引:2,自引:0,他引:2  
This research was supported by a Duke University Research Council Grant. The purpose of this study was to examine mode and speed specificity of strength training by comparing concentric and eccentric isokinetic exercise of the quadriceps. Forty-eight healthy men (mean age = 23.9 years) were randomly assigned to one of three groups: concentric training (C), eccentric training (E), or control (K). Average force (in Newtons) of 3 concentric and of 3 eccentric quadriceps contractions on the KIN-COM(R) dynamometer at 60, 120, and 180 degrees /sec was evaluated prior to and following a 6 week period during which only the C and E groups trained. Training sessions (3/week) included 4 submaximal and 1 maximal warm-up followed by 10 maximal effort isokinetic contractions of the quadriceps at 120 degrees /sec for each leg. Group C subjects trained concentrically only while Group E subjects trained eccentrically only. A t-test for independent means showed no significant right/left differences. ANOVA and Scheffe's F-tests were then used to assess the differences in training effects among the 3 groups for the left leg only. Results showed that although Group C increased slightly in both concentric and eccentric force at all speeds, the gains were significant only for concentric force at 180 degrees /sec. Group E showed significant gains (p < 0.05) in eccentric force at all speeds but not in concentric force. The K group had no significant change in concentric or eccentric force at any speed. We conclude that the eccentric mode of isokinetic exercise has highly specific strength training effects while the concentric mode has less specific training effects. In addition, speed of exercise does not appear to have specific training effects. J Orthop Sports Phys Ther 1989;11(2):70-75.  相似文献   
98.
Immunotoxicity of the Semiconductor Gallium Arsenide in Female B6C3F1 Mice   总被引:1,自引:1,他引:0  
The effects of gallium arsenide (GaAs) exposure on immunocompetenceof B6C3F1 female mice were investigated. GaAs was administeredas a single intratracheal instillation at doses of 50, 100,and 200 mg/kg. Fourteen days after exposure, various cellularand humoral immune parameters were assessed. GaAs exposure increasedspleen cellularity in a dose-dependent manner. However, thepercentages of Thy 1.2 positive and 1g positive cells were decreasedand that of F4/80 positive cells was increased dose dependency.The IgM and IgG antibody-forming cell response of the spleento the T-dependent antigen sheep erythrocytes was reduced by66 and 48%, respectively, at 200 mg/kg. Levels of the serumcomplement protein, C3, were increased by as much as 16% withno significant change in CH50 levels. The mitogenic responseof splenic T cells to Con A and PHA was unaffected by GaAs,but that of B cells to LPS was increased by 52%. The delayedhypersensitivity response to keyhole limpet hemocyanin and mixedlymphocyte response were significantly reduced in a dose-dependentmanner by GaAs exposure. Natural killer cell activity againstthe YAC-1 mouse lymphoma was enhanced in treated mice. Analysisof peritoneal exudate cells (PEC) revealed a dose-dependentdecrease in number and a shift in the composition of PECs. Thepercentage of PEC monocytes increased from 53% of the populationto 81%, while the lymphocytes decreased from 46 to 20%. Theadherent PEC population demonstrated decreased phagocytosisof covaspheres and increased phagocytosis of chicken erythrocytes(CRBC). GaAs exposure had no effect on host resistance to Plasmodiumyoelii or Streptococcus pneumoniae, but dose dependency increasedresistance of the mouse to Listeria monocytogenes Treated micedemonstrated a significantly decreased resistance to the B16F10melanoma with a sevenfold increase in tumor burden at 200 mg/kg.GaAs affects both humoral and cellular immune parameters inmice and impairs the ability of the immune system to protectagainst B16F10 tumor challenge.  相似文献   
99.
100.
Enterotoxin produced by a sporulating culture of Clostridium perfringens type C, which had been isolated from a case of severe necrotic enteritis, was purified. The molecular weight was estimated to be 36,000 by gel chromatography on Sephadex G-100 and 33,400 by ultracentrifugation. The sedimentation coefficient S20,W was 2.92. The toxin protein exhibited unusual behavior on sodium dodecyl sulfate gels, and toxin aggregates having molecular weights of 68,000, 85,000, 105,000, and 140,000 were obtained. The purified enterotoxin often separated, apparently due to slight charge differences, into two protein bands on 7% polyacrylamide gels. Electrofocusing of enterotoxin on polyacrylamide gels gave an approximate isoelectric point of 4.3, with the enterotoxin being fractionated into four distinct protein bands. The specific toxicity of the enterotoxin was about 1,900 mouse mean lethal doses per mg of calculated nitrogen. The data obtained indicate that the enterotoxin from C. perfringens type C is identical in most respects to that obtained from type A strains. Whether or not this toxin plays a role in the necrotic enteritis caused by type C strains is unknown at present.  相似文献   
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