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41.
We sought to compare self-assessment of preoperative anxiety levels and selection of worst fears by surgical patients with the assessments made by the anesthesia and surgery residents providing intraoperative care for those patients. One hundred inpatients at a Veterans Affairs hospital (Group 1) and 45 patients at a University hospital (Group 2) were asked to complete a brief questionnaire; the residents were asked to complete the same questionnaire. Group 1 results showed that median patient visual analog scale (VAS) scores were lower for anxiety about anesthesia compared to surgery (16 vs 22, P < or = 0.05). Anesthesia resident VAS scores were higher than patient or surgery resident scores. Neither type of resident was able to predict their individual patient's VAS score (Kendall's tau). The fear chosen with the greatest incidence by Group 1 patients and residents was "whether surgery would work". A significant number of residents (34%, anesthesia or surgery, P < or = 0.05) matched their patient's fear choice. Residents commonly chose fears related to their specialty (e.g., anesthesia residents chose anesthesia-related fears more often than surgery residents, 50% vs 28%, P < or = 0.001). In Group 2, residents demonstrated an improved ability to predict patient scores. For instance, both surgery and anesthesia residents were able to predict individual University patient VAS scores (P < or = 0.01). The fear chosen with the greatest frequency by Group 2 patients was "pain after the operation". Sixty percent of anesthesia residents matched their patients' fear choice (P < or = 0.001). This study indicates a variable ability of anesthesia and surgery residents to predict patient anxiety and fear which may be due, in part, to difficulty in understanding a Veterans Affairs hospital patient population. 相似文献
42.
We compared development of feline hindlimb collateral circulation after acute occlusion of the terminal aorta by ligation, thrombus formation, and formation of a "closed" aortic loop containing thromboplastin. Collateral circulation development was assessed by aortograms, scintillation scans, neurological signs following occlusion, measurement of hindlimb muscle blood flow, and forelimb and hindlimb temperature. In cats in which aortic occlusion was the result of ligation or thromboplastin in the aortic loop, paralysis was not evident. Aortograms and scintillation scans indicated hindlimb blood flow. Both muscle temperature and blood flow data indicated that the return of blood flow was rapid. The 5th lumbar artery appears to be the origin of the collateral vessels. The mid-zone component is a dorsal and ventral vertebral route and an epaxial muscle route. The reentry components are the 6th or 7th lumbar arteries. The collateral vessels arise from preexisting collateral vessels. Of those cats in which aortic occlusion was the result of a thrombus, all exhibited paralysis. Aortograms, scintillation scans, muscle temperature, and hindlimb blood flow data indicated reduced hindlimb blood flow. The results suggest that the thrombus has an inhibitory effect on the development of collateral circulation. 相似文献
43.
GJ Mancini-Samuelson V Kieweg KM Sabaj S Ghisla MT Stankovich 《Canadian Metallurgical Quarterly》1998,37(41):14605-14612
The modulation of the electron-transfer properties of human medium-chain acyl-CoA dehydrogenase (hwtMCADH) has been studied using wild-type and site-directed mutants by determining their midpoint potentials at various pH values and estimating the involved pKs. The mutants used were E376D, in which the negative charge is retained; E376Q, in which one negative charge (pKa approximately 6. 0) is removed from the active center; E99G, in which a different negative charge (pKa approximately 7.3) also is affected; and E376H (pKa approximately 9.3) in which a positive charge is present. Em for hwtMCADH at pH 7.6 is -0.114 V. Results for the site-directed mutants indicate that loss of a negative charge in the active site causes a +0.033 V potential shift. This is consistent with the assumption that electrostatic interactions (as in the case of flavodoxins) and specific charges are important in the modulation of the electron-transfer properties of this class of dehydrogenases. Specifically, these charge interactions appear to correlate with the positive Em shift observed upon binding of substrate/product couple to MCADH [Lenn, N. D., Stankovich, M. T., and Liu, H. (1990) Biochemistry 29, 3709-3715], which coincides with a pK increase of Glu376-COOH from approximately 6 to 8-9 [Rudik, I., Ghisla, S., and Thorpe, C. (1998) Biochemistry 37, 8437-8445]. From the pH dependence of the midpoint potentials of hwtMCADH two mechanistically important ionizations are estimated. The pKa value of approximately 6.0 is assigned to the catalytic base, Glu376-COOH, in the oxidized enzyme based on comparison with the pH behavior of the E376H mutant, it thus coincides with the pK value recently estimated [Vock, P., Engst, S., Eder, M., and Ghisla, S. (1998) Biochemistry 37, 1848-1860]. The pKa of approximately 7.1 is assigned to Glu376-COOH in reduced hwtMCADH. Comparable values for these pKas for Glu376-COOH in pig kidney MCADH are pKox = 6.5 and pKred = 7.9. The Em measured for K304E-MCADH (a major mutant resulting in a deficiency syndrome) is essentially identical to that of hwtMCADH, indicating that the disordered enzyme has an intact active site. 相似文献
44.
KM Boberg O Fausa T Haaland E Holter OJ Mellbye A Spurkland E Schrumpf 《Canadian Metallurgical Quarterly》1996,23(6):1369-1376
Overlapping features between primary sclerosing cholangitis (PSC and autoimmune hepatitis (AIH) have previously been noted. To assess systematically similarities between these disorders, we have evaluated 114 PSC patients (36 women; 78 men), all confirmed by endoscopic retrograde cholangiography (ERC), according to a scoring system proposed by The International Autoimmune Hepatitis Group for the diagnosis of AIH. The scoring system attributes positive or negative scores to the parameters sex, ratio of elevation of serum levels of alkaline phosphatase (ALP) vs. aminotransferase, serum levels of immunoglobulins and autoantibodies, viral markers, history of drug and alcohol intake, genetic factors, liver histology, and response to therapy. Two of the PSC patients (2%) obtained scores above 15 before treatment, satisfying the diagnostic criterion of "definite" AIH. Thirty-eight patients (33%) scored between 10 and 15 points and could be classified as "probable" AIH. The serum level of immunoglobulin G (IgG) was elevated in 68 patients (61% of 111 cases tested), and positive titers of antinuclear antibodies (ANA) or smooth muscle antibodies (SMA) were detected in 24 patients (22% of 111 cases tested). Thirty-five of the PSC patients (33% of 105 evaluable biopsy specimens) obtained positive scores for histological features similar to those of AIH, but the total score for histology was in the negative range in 72 patients (69%) because of the presence of biliary changes. The frequent finding of high scores in PSC patients underlines the similarities PSC may have with AIH. A modification of the scoring system, in particular by increasing the negative score for histological biliary changes, would improve its potential to discriminate between AIH and PSC. 相似文献
45.
HJ Deeg W Leisenring R Storb J Nims ME Flowers RP Witherspoon J Sanders KM Sullivan 《Canadian Metallurgical Quarterly》1998,91(10):3637-3645
We reviewed the records and reevaluated 212 patients with aplastic anemia transplanted at the Fred Hutchinson Cancer Research Center (FHCRC) between 1970 and 1993 who survived >/=2 years and who have been followed for up to 26 years. Parameters analyzed included hematopoietic function, chronic graft-versus-host disease (GVHD), skin disease, cataracts, lung disease, skeletal problems, posttransplant malignancy, depression, pregnancy/fatherhood, and the return to work or school, as well as patient self-assessment of physical and psychosocial health, social interactions, memory and concentration, and overall severity of symptoms. Survival probabilities at 20 years were 89% for patients without (n = 125) and 69% for patients with chronic GVHD (n = 86) (the status was uncertain in 1 surviving patient). All patients had normal hematopoietic parameters. Skin problems occurred in 14%, cataracts in 12%, lung disease in 24%, and bone and joint problems in 18% of patients. Eleven patients (12%) developed a solid tumor malignancy and 19% of patients experienced depression. Chronic GVHD was the dominant risk factor for late complications. Seventeen patients died at 2.5 to 20.4 years posttransplant; 13 of these had chronic GVHD and related complications. At 2 years, 83% of patients had returned to school or work; the proportion increased to 90% by 20 years. At least half of the patients preserved or regained the ability to become pregnant or father children. Patients rated their quality of life as excellent and symptoms as minimal or mild. In conclusion, marrow transplantation in patients with aplastic anemia established long-term normal hematopoiesis. No new hematologic disorders occurred. The major cause of morbidity and mortality was chronic GVHD. However, the majority of patients who survived beyond 2 years returned to a fully functional life. 相似文献
46.
ED Engelstein KM Stein SM Markowitz BB Lerman 《Canadian Metallurgical Quarterly》1996,27(5):1098-1105
OBJECTIVES: This study sought to present evidence that fast atrioventricular (AV) node pathways with posterior exit sites may participate in typical AV node reentry. BACKGROUND: Catheter ablation of the slow AV node pathway in the posteroseptal right atrium is the preferred therapeutic approach in patients with AV node reentrant tachycardia. Despite the success achieved with this approach, electrophysiologic changes consistent with fast pathway ablation are occasionally observed. One potential explanation is the presence of an aberrant posterior fast pathway. METHODS: The location of fast and slow AV node pathways was determined by atrial activation mapping along the tricuspid valve annulus during tachycardia and was further confirmed by the effect of radiofrequency catheter ablation. RESULTS: Seven patients with AV node reentrant tachycardia had evidence of a posterior fast pathway near the coronary sinus os. Abolition of anterograde and retrograde fast pathway conduction followed radiofrequency ablation in the posteroseptal region in six patients. Consistent with fast pathway ablation, the AH interval increased from 70 +/- 24 to 195 +/- 35 ms (mean +/- SD), and tachycardia was no longer inducible. Selective slow pathway ablation was performed in one other patient with a posterior fast pathway. CONCLUSIONS: Functionally fast AV node pathways may be located in the posteroseptal right atrium, where slow pathway modification is performed. These data delineate the limitation of an anatomically guided slow pathway ablative approach and emphasize the importance of detailed mapping and localization of the retrograde fast pathway exit site before ablation. Failure to recognize the presence of posterior fast AV node pathways may account for sporadic examples of AV block, complicating posteroseptal ablation in patients with AV node reentry. 相似文献
47.
CW Shuttleworth AJ Burns SM Ward WE O'Brien KM Sanders 《Canadian Metallurgical Quarterly》1995,68(4):1295-1304
Neurons that synthesize nitric oxide from arginine produce stoichiometric amounts of citrulline. We investigated whether nitric oxide-releasing enteric neurons have the capacity to recycle citrulline to arginine and thereby sustain nitrergic neurotransmission. Argininosuccinate synthetase-like immunoreactivity and argininosuccinate lyase-like immunoreactivity, enzymes capable of citrulline to arginine conversion, were both localized in discrete populations of myenteric and submucosal neurons in the canine proximal colon. Argininosuccinate synthetase-like immunoreactivity and argininosuccinate lyase-like immunoreactivity co-localized with neuronal beta-nicotinamide adenine dinucleotide phosphate diaphorase staining, a marker for nitric oxide synthase. The functional significance of argininosuccinate synthetase-like immunoreactivity and argininosuccinate lyase-like immunoreactivity was shown by testing the effects of exogenous citrulline on responses to enteric inhibitory nerve stimulation, which were assessed by measuring contractions, inhibitory junction potentials and electrical slow waves. As shown previously, arginine analogues (L-nitroarginine methyl ester or L-nitroarginine; 100 microM) inhibited nitric oxide-dependent responses, and excess L-arginine restored inhibitory responses. Citrulline alone (0.1-2 mM) had no effect on nitrergic transmission under control conditions, but in the presence of L-nitroarginine methyl ester or L-nitroarginine, citrulline (0.1-2 mM) restored nitrergic transmission in a concentration-dependent manner. Other neutral amino acids (L-serine, L-leucine) did not mimic the effects of citrulline. Taken together, these data suggest that enteric nitrergic neurons have the enzymatic apparatus and functional capability of recycling citrulline to arginine. 相似文献
48.
49.
RR Frazier ES Millican SK Watson NJ Oldroyd RL Sparkles KM Taylor S Panchal L Bark CP Kimpton PD Gill 《Canadian Metallurgical Quarterly》1996,17(10):1550-1552
The Applied Biosystems (ABI) Prism 377 DNA sequencer has been evaluated in an attempt to increase the throughput of samples for short tandem repeat (STR) analysis, in both forensic casework and the UK National Criminal Intelligence DNA Database. The gel system assessed consisted of 0.2 mm, 4% acrylamide 6 M urea gels, with a well-to-read distance of 36 cm. Gels were run at a constant voltage of 3 kV and constant temperature of 51 degrees C. The run time of our second generation multiplex (SGM) STR system was achieved in less than 2 h. Rigorous validation has been performed on the instrument hardware and software. Complete resolution of 1 base differences was obtained, up to and beyond 350 bases; sizing precision across gels was more than 2-fold higher than the 373A and the sensitivity was increased by one third. 相似文献
50.
J Marszalek W Zhang TR Hupp C Margulies KM Carr S Cherry JM Kaguni 《Canadian Metallurgical Quarterly》1996,271(31):18535-18542
DnaA protein of Escherichia coli is a sequence-specific DNA-binding protein required for the initiation of DNA replication from the chromosomal origin, oriC. It is also required for replication of several plasmids including pSC101, F, P-1, and R6K. A collection of monoclonal antibodies to DnaA protein has been produced and the primary epitopes recognized by them have been determined. These antibodies have also been examined for the ability to inhibit activities of DNA binding, ATP binding, unwinding of oriC, and replication of both an oriC plasmid, and an M13 single-stranded DNA with a proposed hairpin structure containing a DnaA protein-binding site. Replication of the latter DNA is dependent on DnaA protein by a mechanism termed ABC priming. These studies suggest regions of DnaA protein involved in interaction with DnaB protein, and in unwinding of oriC, or low-affinity binding of ATP. 相似文献