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991.
992.
Transendoscopic pulsed dye laser lithotripsy was effective in the treatment of calcium carbonate urothlithiasis in 2 adult geldings. Perineal urethrotomy provided convenient access for standing transendoscopic lithotripsy and evacuation of a large cystic calculus in one gelding. In the second horse, an obstructive urethral calculus was fragmented and removed by a transurethroscopic approach. Pulsed dye laser lithotriptor is effective in fragmentation of the most common form (calcium carbonate) of uroliths in horses and may be performed in standing horses with reduced surgical invasiveness and trauma to the urinary tract, compared with conventional approaches. The principle disadvantages include cost of the procedure, which is comparable to laparocystotomy, and the time delay required to make arrangements for use of the pulsed dye laser lithotriptor. 相似文献
993.
STUDY OBJECTIVE: To describe the effectiveness of an emergency medical education program in a postwar developing country. METHODS: A prospective, nonrandomized interrupted time-series study was conducted in an emergency department at a national referral hospital in Rwanda immediately after the 1994 civil war. Participants included 11 medical personnel staffing the ED comprising physicians, nurses, and medical assistants. International medical relief workers in the ED identified deficiencies by directly observing routine clinical practices. On the basis of this assessment, formal training programs in trauma resuscitation, airway management, wound care, and blood/fluid precautions were conducted. Subjects were then observed 1 week and 2 months after the educational programs and scored on a standardized data-collection form. Scores before and after intervention were compared with the use of Fisher's exact test to determine program effectiveness. RESULTS: Educational interventions with statistically significantly longer term effects included wound management principles and blood/fluid precautions (before versus after intervention, P < .05). Interventions with the least sustained effect included advanced airway interventions and procedures related to trauma resuscitation. CONCLUSION: Educational seminars proved to have the greatest sustained effect on those behaviors requiring minimal equipment and noncomplex medical decisionmaking. 相似文献
994.
MC Wehby-Grant CE Olmstead WJ Peacock DA Hovda RJ Gayek RS Fisher 《Canadian Metallurgical Quarterly》1996,24(2):79-91
The metabolic changes that occur in the neonatal brain as a result of hydrocephalus, and the response to ventriculoperitoneal shunting, vary with the maturational stage of the brain. In this study, local glucose utilization (LCMRglu) and oxidative metabolic capacity were estimated using 2-deoxyglucose autoradiography and cytochrome oxidase histochemistry, respectively. Hydrocephalus was induced in rabbit pups via intracisternal kaolin injections at 4-6 days of age. Shunting occurred at 19-26 days of age and the animals were sacrificed at ages ranging from 33 to 331 days. In normal animals there was a high glucose demand early in life which showed a decrease at about 60 days of age. In rabbits sacrificed prior to 60 days of age the controls showed the highest LCMRglu with significant decreases in both the hydrocephalic and shunted animals. After 60 days of age the shunted animals had higher LCMRglu than both the hydrocephalic and control subjects. Oxidative metabolic capacity peaked before 50 days of age in normal animals. At the youngest age, both the hydrocephalic and shunted animals showed higher cytochrome oxidase density rates than the control rabbits. In the older group, the hydrocephalic animals remained high while the shunted animals approximated the control densities. Neither the changes seen in the LCMRglu nor the oxidative metabolic capacity were correlated with changes in cell packing density or increased intracranial pressure. These data suggest that when the brain is compromised by hydrocephalus, there is an initial compensatory increase in oxidative metabolic capacity. The development of the glycolytic pathway appears to be retarded by hydrocephalus, but with shunting and the passage of time, the LCMRglu rebounds to levels above that of controls. 相似文献
995.
Thirty consecutive patients with amputation or devascularizing injuries of the thumb or two or more fingers proximal to the PIP joint were reviewed. Replantation or revascularization had been done in 27 patients, in 24 successfully. Three patients had primary amputation. The distribution of calculable costs was dominated by those for sick leave (49%), operation (26%) and ward costs (20%). Out-patient care, physiotherapy and travel together constituted only 6%. The cost of a successful replantation was equal to 1.6 times the mean annual salary of these patients and that of primary amputation about half as much. Mobility, power and performance of a standardized grip test were better for the successfully replanted or revascularized patients. Subjective evaluation of 23 parameters of function, cosmesis and quality of life did not disclose any differences. All patients except three had returned to their original work within 2 years. 相似文献
996.
BACKGROUND: Polyethylene glycol (PEG) has been shown to potentiate antigen-antibody reactions. STUDY DESIGN AND METHODS: To investigate the utility of PEG in pretransfusion testing, a blinded comparison study of PEG and a low-ionic-strength additive solution (LISS) was conducted. A total of 500 patient samples were tested in parallel with reagent antibody-detection cells using blind-coded PEG and LISS potentiators. RESULTS: In 34 (34%) of 100 samples with known antibodies in the Rh, Kell, Duffy, Kidd, and MNS systems, PEG antiglobulin reactions were stronger (total score, 382) than LISS antiglobulin reactions (total score, 216), and in 66 cases (66%), they were equal to those of LISS. Of 400 samples without detectable antibodies, 384 were negative with PEG and LISS, and 16 were positive in PEG tests and negative in LISS. Seven of the 16 were clinically important antibodies (D, 1; E, 3; Fya, 1; Jka; 1; Jkb, 1), and four were clinically benign antibodies (Le(a), 2; McCc, 1; Sda, 1). Five of the 16 demonstrated inconclusive PEG reactions, for a false-positive rate of 5 in 400 (1.3%). Of the 500 samples, none was negative in PEG tests and positive in LISS (0% false-negative rate). CONCLUSION: Although PEG demonstrates a relatively high false-positive rate, PEG is more sensitive than LISS in detecting clinically significant antibodies. 相似文献
997.
998.
H Krakauer MJ Lin EM Schone D Park RC Miller J Greenwald RC Bailey B Rogers G Bernstein DE Lilienfeld SM Stahl RS Crawford DC Schutt 《Canadian Metallurgical Quarterly》1998,4(1):11-29
The functioning of working memory in schizophrenic patients according to Baddeley's model was examined in two complementary experiments. Experiment 1 comprised 27 patients and their controls, matched in age and level of education. Of this pool, 20 pairs participated also in Experiment 2. Digit span, reading rate, and immediate serial recall assessed the functioning of the phonological loop. Corsi and pattern span tasks assessed the capacity of visuo-spatial memory. The central executive's ability to monitor two concurrent tasks was evaluated in a dual task paradigm, and its capacity to control action in a random generation task. A preliminary set of analyses showed that the patients' performances were reduced in all tasks explored, except in digit span. This initial pattern changed consistently after controlling for reading rate. While slow and fast reading patients were comparable in demographic and clinical criteria, slow reading patients showed impaired performance in all tasks, whereas fast reading patients exhibited reduced performance in visuo-spatial tasks and in the random generation task only. The state of functioning of working memory in schizophrenia appears, therefore, to vary consistently among the components of the model and is markedly impaired in slow reading patients. The implications of slowness are discussed. 相似文献
999.
RS Larson MA Scott TL McCurley CL Vnencak-Jones 《Canadian Metallurgical Quarterly》1996,56(19):4378-4381
The genetic mechanisms that give rise to posttransplant lymphoproliferative disorders (PTLDs) are not well established, yet previous studies have focused or) the role of immunosuppression and EBV infection. We investigated whether microsatellite analysis could: (a) determine the recipient/donor origin of the tumor; and (b) document novel genetic alterations in PTLDs, i.e., microsatellite instability. We characterized seven cases of PTLD (five B-cell and two T-cell non-Hodgkin's lymphomas) in which donor allograft tissue, normal recipient tissue, and tissue from the PTLDs were available. In each case, six microsatellite loci were analyzed. Five cases were of host origin (three B-cell and two T-cell lymphomas). The two cases of donor origin were B-cell lymphomas. Multiple loci showed microsatellite instability in two cases of host-derived T-cell non-Hodgkin's lymphomas (28% of PTLDs). These findings show that microsatellite analysis may be used to determine the host or donor origin of PTLDs and suggest for the first time that defective DNA mismatch repair may be an underlying genetic mechanism of lymphomagenesis in some cases of PTLD. 相似文献
1000.