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101.
R Germann M Haisjackl B Schwarz N Salak E Deusch W Pajk HJ Wolf B Riedmann W Hasibeder 《Canadian Metallurgical Quarterly》1997,79(3):357-362
Haemorrhage is associated with intestinal mucosal hypoxia and impaired gut barrier function. Dopamine increases oxygen delivery to the intestinal mucosa and may thus counteract haemorrhage-induced mucosal hypoxia. Jejunal mucosal tissue oxygen tension (mucosal PO2) and jejunal oxygen saturation of mucosal microvascular haemoglobin (mucosal HbO2) were measured in 14 anaesthetized pigs. Seven animals served as controls (group C) and seven received continuous infusion of dopamine 16 micrograms kg-1 min-1 (group D) while 45% of blood volume was removed in three equal increments. Resuscitation was performed using shed blood and fluid. Mean arterial pressure and systemic oxygen delivery decreasing significantly during haemorrhage and returned to baseline after resuscitation in both groups. Mucosal PO2 decreased from 4.4 to 1.7 kPa after haemorrhage (P < 0.01) and further to 1.5 kPa after resuscitation (P < 0.01) in group C whereas group D showed an increase from 3.9 to 5.9 kPa after the start of the dopamine infusion (P < 0.05), but no significant difference from baseline after haemorrhage (2.3 kPa) (ns) or resuscitation (3.1 kPa) (ns). Mucosal HbO2 decreased from 52 to 32% after haemorrhage (P < 0.05) and increased to near baseline (37%) (ns) after resuscitation in group C whereas group D showed no significant changes from baseline (54%) throughout the experiment. Comparison between groups showed higher mucosal PO2 and HbO2 values for group D animals after the start of the dopamine infusion (P < 0.05 each), after the first two steps of haemorrhage (P < 0.01 each) and after resuscitation (P < 0.05 each). We conclude that i.v. dopamine 16 micrograms kg-1 min-1 improved tissue oxygenation of the small intestinal mucosa during moderate haemorrhage and subsequent resuscitation. 相似文献
102.
There are three selenium-containing proteins in human plasma: glutathione peroxidase (GSH-Px-P), albumin and selenoprotein Ph, the human analogue to selenoprotein P from rat plasma. Selenoprotein Ph was separated from the two other selenium-containing proteins by Heparin Sepharose chromatography and was shown to have about 60-70% of the total plasma selenium, while both GSH-Px-P and albumin contain about 15%. A 2588-fold purification from human plasma was achieved by using a four-step procedure. SDS-PAGE of the purified selenoprotein revealed, besides one contaminant selenium-free protein band at about 70 kDa, one selenium-containing band ranging from 54 to 67 kDa with a maximum at 63 kDa. This microheterogeneity, also recognized by IEF, may be due to the glycprotein nature of the selenoprotein Ph. The determination of the molecular mass of the native protein varied from 65 kDa using gel filtration on Fraktogel HW 55 to 89 kDa on Sephacryl S-200 HR, suggesting an interaction between the gel-matrices and selenoprotein Ph. 相似文献
103.
AW Jones 《Canadian Metallurgical Quarterly》1993,39(9):1837-1844
The concentration-time profiles of ethanol were determined for capillary blood, end-expired breath, and saliva after 21 healthy men ingested ethanol at 0.68 g/kg body weight. Near the time of obtaining body fluids, the volunteers estimated their feelings of intoxication, and body sway (with open and closed eyes), hand tremor, positional alcohol nystagmus (PAN), and roving ocular movements (ROM) were quantitatively recorded. The concentration-time profiles of ethanol in blood, breath, and saliva agreed well within individuals but there were large variations between subjects. The mean saliva-ethanol profiles ran slightly above those for blood and breath. Subjective ratings of intoxication and impairment of body function (standing steadiness and hand steadiness) were highest at the time of reaching the peak concentrations of ethanol in body fluids. PAN was evident in most subjects between 60 and 120 min after the start of drinking, whereas ROM appeared mainly during the postabsorptive phase of ethanol kinetics (120-420 min). The blood ethanol concentration thresholds were between 500 and 700 mg/L (50-70 mg/dL) when the diminished performance had recovered to baseline values. 相似文献
104.
Creation of a dynamic levator aponeurosis fold or double eye adds to the beauty of the East Asian. The eyes are larger and less puffy, and the eyelashes appear longer and curve up and out instead of down. The distance from the ciliary border to the eyebrow is decreased and more in proportion. The Mongolian trait is preserved. 相似文献
105.
RB Jones PR Pomrehn RE Mecklenburg EA Lindsay M Manley JK Ockene 《Canadian Metallurgical Quarterly》1993,124(9):92-104; discussion 106-8
The National Cancer Institute's program to help dentists reduce tobacco use among their patients is part of the Community Intervention Trial for Smoking Cessation, a 22-community, randomly controlled trial of an intervention program for smoking cessation. Results of COMMIT baseline surveys of dentists in the 11 intervention communities are presented. 相似文献
106.
Jones Enrico E.; Ghannam Jess; Nigg Joel T.; Dyer Jennifer F. 《Canadian Metallurgical Quarterly》1993,61(3):381
Articulates a paradigm for single-case research in psychotherapy. A patient diagnosed as having major depressive disorder was seen in an intensive, twice-weekly psychodynamic psychotherapy for 2.5 years. Each session was videotaped, and assessments of patient change were obtained at regular intervals. A time-series analysis was used to model fluctuations in the therapy process to take into account time and the effect of previous events on subsequent changes, thereby preserving the context-determined meaning for therapist and patient actions. A bidirectional analysis of causal effects shows that the influence processes between therapist and patient are mutual and reciprocal and suggests that the effect of the patient on the therapist and on the process has not been made sufficiently explicit in previous models of process and change. The potential of intensive single-case designs for uncovering causal effects in psychotherapy is demonstrated. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
107.
S Petrasch LJ van Tits HJ Motulsky OE Brodde MC Michel 《Canadian Metallurgical Quarterly》1993,43(8):904-908
The effects of the antiasthmatic drug ketotifen (CAS 34580-13-7) on human mononuclear leukocytes were studied in vitro and in vivo. In vitro ketotifen concentration-dependently inhibited mitogen-stimulated lymphocyte proliferation. High ketotifen concentrations also inhibited T-lymphocyte mitogen- and adenosine triphosphate stimulated increases in intracellular Ca2+ in lymphocytes and the U937 human monocyte precursor cell line, respectively; this involved inhibition of both Ca2+ influx and intracellular mobilization. In in vivo experiments, treatment of healthy volunteers with 1 mg ketotifen b.i.d. for 7 d did not alter the number or subset composition of circulating lymphocytes. Moreover, the mitogen-stimulated in vitro proliferation of lymphocytes obtained before and after ketotifen treatment in vivo was similar. It is concluded that high ketotifen concentrations can inhibit the activation of resting lymphocytes in vitro but standard ketotifen treatment does not notably affect the number of function of circulating lymphocytes in vivo. 相似文献
108.
A card survey was sent to 340 veterinarians in the Urban, Delta, Highland and Coastal Plain regions of Arkansas. Veterinarians were asked to indicate numbers of dogs tested, confirmed Dirofilaria immitis positive, diagnostic techniques, frequency and period tested. A significantly greater percentage of dogs tested D. immitis positive in the Delta region as compared with the Urban region. There were no significant differences in the percentage of treated dogs on prophylaxis or the types of diagnostic tests among regions. 相似文献
109.
OBJECTIVES: Reoperative coronary artery bypass grafting presents unique challenges for myocardial preservation. The purpose of this study was to compare oxygenated blood cardioplegia with oxygenated crystalloid cardioplegia during reoperative coronary artery bypass grafting using transesophageal echocardiography to assess regional wall motion of the left ventricle before and after cardiopulmonary bypass. METHODS: Sixty-one patients undergoing reoperative coronary artery bypass grafting were prospectively randomized to receive oxygenated blood cardioplegia or oxygenated crystalloid cardioplegia delivered with a combined antegrade-retrograde technique. Transgastric short axis views of the left ventricle were made with transesophageal echocardiography during the operation before cardiopulmonary bypass and immediately after cardiopulmonary bypass. Regional wall motion was graded by a blinded observer, and before cardiopulmonary bypass scores were compared with after cardiopulmonary bypass scores. RESULTS: No significant differences were found in the change in regional wall motion score from before cardiopulmonary bypass to after cardiopulmonary bypass between the blood and crystalloid cardioplegia groups. CONCLUSIONS: This study found blood and crystalloid cardioplegia to be equally efficacious for myocardial preservation during reoperative coronary artery bypass grafting. 相似文献
110.