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151.
MA Judson 《Canadian Metallurgical Quarterly》1998,11(3):738-744
Patients with end-stage sarcoidosis have now undergone lung transplantation successfully with good short-term and intermediate-term results. Lung transplantation for sarcoidosis requires several considerations unique to this disease. Selection of pulmonary sarcoidosis patients for transplantation requires that medical therapy has been exhausted. This may involve the use of corticosteriods and alternative medications. Causes of pulmonary dysfunction other than pulmonary sarcoidosis, such as bronchiectasis and myocardial sarcoidosis, must be excluded before candidates are considered for transplantation. The extent and severity of extrapulmonary disease must also be assessed and may preclude lung transplantation. The presence of mycetomas is considered a relative contra-indication by some transplant centres and an absolute contra-indication by others. Relatively few patients with pulmonary sarcoidosis have undergone transplantation and, therefore, there are few data on outcome. Sarcoidosis frequently recurs in the allograft, but rarely causes symptoms or pulmonary dysfunction. More severe acute rejection episodes may occur in sarcoidosis transplant recipients, although at present there is no evidence of an increased risk of obliterative bronchiolitis or increased mortality. 相似文献
152.
An experiment was performed to determine the effect of elevated prostaglandin F2 alpha (PGF2 alpha) on pregnancy rates of progestogen-treated bred cows in the presence or absence of luteal tissue. Ninety-one beef cows were bred (Day 0) and assigned randomly to receive either 3 mL saline (CON), 15 mg PGF2 alpha, or 15 mg PGF2 alpha + lutectomy (P + L) administered intramuscularly (i.m.) at 8 h intervals on either Days 5-8, 10-13, or 15-18 postbreeding. Lutectomies were performed by transrectal digital pressure before initiation of treatment on Day 5, 10, or 15 for the respective treatment groups. All cows were fed 4 mg/day of melengesterol acetate from two days prior to initiation of treatment until Day 30 postbreeding. Mean concentrations of 13,14-dihydro-15-keto-PGF2 alpha (PGFM) were increased in cows administered PGF2 alpha and P + L treatments (398 +/- 23 and 413 +/- 22 pg/ml, respectively; p < 0.01) compared to the CON group (80 +/- 29 pg/ml) regardless of treatment group. Mean concentrations of oxytocin (OT) were increased in cows given PGF2 alpha on Day 10 and 15 (p < or = 0.0001) and tended to be increased on d 5 when compared to CON and P + L treatment groups on Day 5. Pregnancy rates were reduced (p < or = 0.03) in the PGF2 alpha treatment group (23%) and by Day 5-8 compared to CON (72%). Lutectomy tended to improve pregnancy rate in P + L (5-8; 55%) compared to PGF2 alpha (5-8; p = 0.1). Pregnancy rates tended (p < or = 0.07) to increase in the PGF2 alpha treatment groups on Days 5-8 treatment (23%, 50%, and 60% for Days 5-8, 10-13, and 15-18, respectively). The later the treatments were initiated pregnancy rates did not differ between treatments given on Days 10-13 and 15-18. In conclusion, the most susceptible period of embryonic growth to the negative effects of PGF2 alpha was during morula to blastocyst development. Removal of luteal tissue diminishes the negative effects of PGF2 alpha through interruption of the luteal oxytocin-uterine PGF2 alpha feedback loop. 相似文献
153.
We report a long-term follow-up of abduction-extension osteotomy of the first metacarpal, performed for painful trapeziometacarpal osteoarthritis. Of a consecutive series of 50 operations, 41 thumbs (82%) were reviewed at a mean follow-up of 6.8 years. Good or excellent pain relief was achieved in 80%, and 93% considered that surgery had improved hand function, while 82% had normal grip and pinch strength, with restoration of thumb abduction. Metacarpal osteotomy was equally successful in relieving symptoms of those with early (grade 2) and moderate (grade 3) degenerative changes. This simple procedure provides lasting pain relief, corrects adduction contracture and restores grip and pinch strength, giving good results with few complications. 相似文献
154.
155.
JM Prins FN Lauw BH Derkx P Speelman EJ Kuijper J Dankert SJ van Deventer 《Canadian Metallurgical Quarterly》1998,114(2):215-219
Muscle activity produces an electrical signal termed the myo-electric signal (MES). The MES is a useful clinical tool, used in diagnostics and rehabilitation. This signal is typically stored in 2 bytes as 12-bit data, sampled at 3 kHz, resulting in a 6 kbyte s-1 storage requirement. Processing MES data requires large bit manipulations and heavy memory storage requirements. Adaptive differential pulse code modulation (ADPCM) is a popular and successful compression technique for speech. Its application to MES would reduce 12-bit data to a 4-bit representation, providing a 3:1 compression. As, in most practical applications, memory is organised in bytes, the realisable compression is 4:1, as pairs of data can be stored in a single byte. The performance of the ADPCM compression technique, using a real-time system at 1 kHz, 2 kHz and 4 kHz sampling rates, is evaluated. The data used include MES from both isometric and dynamic contractions. The percent residual difference (PRD) between an unprocessed and processed MES is used as a performance measure. Errors in computed parameters, such as median frequency and variance, which are used in clinical diagnostics, and waveform features employed in prosthetic control are also used to evaluate the system. The results of the study demonstrate that the ADPCM compression technique is an excellent solution for relieving the data storage requirements of MES both in isometric and dynamic situations. 相似文献
156.
Vanable Peter A.; McKirnan David J.; Buchbinder Susan P.; Bartholow Bradford N.; Douglas John M. Jr.; Judson Franklyn N.; MacQueen Kathleen M. 《Canadian Metallurgical Quarterly》2004,23(5):525
Alcohol use may increase HIV sexual risk behavior, although findings have varied across study populations and methods. Using event-level data from 1,712 seronegative men who have sex with men, the authors tested the hypothesis that social context would moderate the effect of alcohol consumption on unprotected anal sex (UAS). For encounters involving a primary partner, rates of UAS did not vary as a function of alcohol use. However, consumption of 4 or more drinks tripled the likelihood of UAS for episodes involving a nonprimary partner. Thus, the effects of alcohol vary according to the context in which it is used. Interventions to reduce substance-related risk should be tailored to the demands of maintaining sexual safety with nonprimary partners. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
157.
Acidosis in cattle: a review 总被引:1,自引:0,他引:1
Acute and chronic acidosis, conditions that follow ingestion of excessive amounts of readily fermented carbohydrate, are prominent production problems for ruminants fed diets rich in concentrate. Often occurring during adaptation to concentrate-rich diets in feedyards, chronic acidosis may continue during the feeding period. With acute acidosis, ruminal acidity and osmolality increase markedly as acids and glucose accumulate; these can damage the ruminal and intestinal wall, decrease blood pH, and cause dehydration that proves fatal. Laminitis, polioencephalomalacia, and liver abscesses often accompany acidosis. Even after animals recover from a bout of acidosis, nutrient absorption may be retarded. With chronic acidosis, feed intake typically is reduced but variable, and performance is depressed, probably due to hypertonicity of digesta. Acidosis control measures include feed additives that inhibit microbial strains that produce lactate, that stimulate activity of lactate-using bacteria or starch-engulfing ruminal protozoa, and that reduce meal size. Inoculation with microbial strains capable of preventing glucose or lactate accumulation or metabolizing lactate at a low pH should help prevent acidosis. Feeding higher amounts of dietary roughage, processing grains less thoroughly, and limiting the quantity of feed should reduce the incidence of acidosis, but these practices often depress performance and economic efficiency. Continued research concerning grain processing, dietary cation-anion balance, narrow-spectrum antibiotics, glucose or lactate utilizing microbes, and feeding management (limit or program feeding) should yield new methods for reducing the incidence of acute and chronic acidosis. 相似文献
158.
M Canis R Botchorishvili K Slim D Pezet JL Pouly A Wattiez C Pomel FN Masson G Mage J Chipponi MA Bruhat 《Canadian Metallurgical Quarterly》1996,25(7):699-709
Colo-rectal endometriosis requiring colon resection are reported in 8 patients to illustrated the diagnostic and therapeutic problems encountered in the management of this uncommon localisation. Pericatamenial or catamenial bowel symptoms associated with pelvic genital involvement were encountered in all cases. Clinical examination, barium enema and colonoscopy are essential to guide surgical management looking for multiple localisations. However their diagnostic value is low as endometriosis rarely involves the mucosa. Endosonography appears to be very promising in evaluating the depth of infiltration of the bowel. The treatment of bowel endometriosis is controversial and varies greatly according to the patient's complaints and clinical data. The indications and limits of all treatment modalities including abstention, medical, and surgical treatment are discussed. From the cases reported we conclude that symptomatic bowel endometriosis should be fully excised whenever possible, and the surgical procedure should be adapted to the depth of infiltration. A full thickness excision or bowel resection is mandatory in patients with deep muscularis involvement. These procedures, which are often difficult due to extensive fibrosis and adhesions, may be achieved by laparoscopy in selected patients. 相似文献
159.
OBJECTIVES: Slow potentials appearing during simple repetitive acral limb movement were investigated. Twenty-six patients suffering from drug resistant partial epilepsies and explored with implanted intracerebral electrodes were examined using two protocols. METHODS: In 18 patients, readiness potential (RP), in 13 patients contingent negative variation (CNV), and in 7 patients both protocols, were tested. The recordings from leads with evident pathological EEG activity were excluded from evaluation. The results concerning the slow potentials preceding the movements in RP and CNV protocols have already been published. RESULTS: The movement-accompanying slow potentials (MASP) were polyphasic or monophasic, started before or during the movement. In the primary motor cortex they followed the pre-movement potentials depending on the protocol: in the RP paradigm they were present only contralateral to the movement, but were bilateral in the CNV protocol. In other areas they either followed the potentials preceding the movement, in some cases with opposite polarity, or they occurred alone. MASP was recorded in motor and supplementary motor, premotor and prefrontal, midtemporal, somatosensory, superior parietal and cingular cortices. The cingular cortex was heavily involved in the self-paced movements but rarely in the cued movements. CONCLUSION: The major involvement of the cingular gyrus contrasted with the absence of slow potentials in temporal limbic structures. MASP is evidently a heterogenic phenomenon. Its genesis could be involved in a spread of information through the relevant structures. 相似文献
160.
We attempted to determine health and economic outcomes from the perspective of an integrated health system of administering enoxaparin 30 mg twice/day versus heparin 5000 U twice/day for prophylaxis against venous thrombosis after major trauma. A decision-analytic model was developed from best literature evidence, institutional data, and expert opinion. We assumed that 40% of proximal deep vein thromboses (DVTs) and 5% of distal DVTs are diagnosed and confirmed with initial or repeat duplex scanning; 50% of undiagnosed proximal DVTs result in pulmonary embolism; 2% and 1% of undiagnosed proximal DVTs will lead to readmission for DVT and pulmonary embolism, respectively, and pulmonary embolism-related mortality rates range from 8-30%. Length of hospital stay data and 1996 institutional drug use and acquisition cost data were used to estimate the cost of enoxaparin and heparin therapy. Diagnosis and treatment costs for DVT and pulmonary embolism were derived from institutional charge data using cost:charge ratios. A second analysis of patients with lower extremity fractures was completed. One-way and multiway sensitivity analyses were performed. For 1000 mixed trauma patients receiving enoxaparin versus heparin, our model showed that 62.2 (95% CI -113 to -12) DVTs or pulmonary emboli would be avoided, resulting in 67.6 (8 to 130) life-years saved at a net cost increase of $104,764 (-$329,300 to $159,600). Enoxaparin versus heparin resulted in a cost of $1684 (-$3600 to $9800) for each DVT or pulmonary embolus avoided and a discounted cost/life-year saved of $2303 (-$8100 to $19,000). For 1000 patients with lower extremity fractures, enoxaparin versus heparin resulted in a cost of $751 (-$4200 to $3300) for each DVT or pulmonary embolus avoided and a discounted cost/life-year saved of $1017 (-$10,200 to $6300). Although enoxaparin increases overall health care costs, it is associated with a cost/additional life-year saved of only $2300, which is generally lower than the commonly used hurdle rate of $30,000/life-year saved. The cost-effectiveness ratio is more favorable in patients with lower extremity fractures than in the general mixed trauma population. 相似文献