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91.
Acute nonfatal erysipelas was diagnosed in 4 sows in a 1,000-sow commercial farrow-to-finish operation in Indiana. Sows were pyrexic, lethargic, lame, and had multiple, 1.3- to 7.6-cm, erythematous rhomboid skin lesions. Outbreak was attributed to failure to properly vaccinate pigs. Further morbidity and mortality were prevented by treatment of clinically affected sows and all pigs in close proximity with procaine penicillin G daily for 3 consecutive days and vaccination of all pigs with questionable vaccination status, using bacterin of killed Erysipelothrix rhusiopathiae. Periodic review of herd management protocols is important to ensure that recommended vaccination schedules are being followed and animals are receiving quality vaccinations. Human error can contribute to many production problems and should be included on the differential diagnoses list. 相似文献
92.
93.
BM Katzman DM Klein TC Garven DA Caligiuri J Kung ED Collins 《Canadian Metallurgical Quarterly》1998,23(4):653-657
Sustained iontophoresis of NMDA potentiated visual responses for minutes after the application in 16 of 38 cells (42%), peaking 3 min after the end of the application and declining to control levels within 12 min. Potentiation was also seen after application of ACPD (36%, n = 14) and AMPA (29%, n = 14), but not after application of ACh (n = 20). ACh also excites dLGN cells, but does not interact with amino acid receptors, and ACh receptors are not directly involved in the transmission of visual information. We suggest that this modulation is a form of visually induced potentiation which permits dynamic modification of the strength of visual information to be relayed to the cortex depending upon the history of previous activity levels. 相似文献
94.
MM Idu J Buth WC Hop P Cuypers ED van de Pavoordt JM Tordoir 《Canadian Metallurgical Quarterly》1998,27(3):399-411; discussion 412-3
PURPOSE: The objective of this study was to assess the accuracy of color-flow duplex surveillance parameters to detect infrainguinal vein graft stenoses and to investigate whether graft revision without angiography is justified. METHODS: In a prospective study in which three centers participated, the data of graft surveillance in 300 patients were analyzed. For the evaluation of surveillance criteria all patients underwent a digital subtraction angiography if a graft stenosis was suspected. To create a control group, in patients with normal grafts a consented digital subtraction angiography was performed also. From these data the accuracy of seven duplex and three ankle blood pressure-derived variables was assessed. The relation between various surveillance criteria and continued graft patency was determined with life table analysis with the transient state method. RESULTS: The mean follow-up period was 20 months (range, 1 to 40 months). At univariate and multivariate analysis the peak systolic velocity (PSV) ratio provided the best correlation with angiographic stenoses > or = 70% (PSV ratio cutoff 3.0: sensitivity 80%, specificity 84%). This finding did not differ between the participating centers. With life table methods it was demonstrated that the best combination of efficacy (limitation of the number of unnecessary revisions), safety (minimal number of correctable lesions missed), and reduction of angiograms was obtained by a two-parameter surveillance algorithm. This algorithm included a PSV ratio < 2.5 to delineate patients in whom a conservative approach without angiography or revision was appropriate, a PSV ratio > or = 4.0 to indicate patients in whom vein graft revision without angiography could be scheduled, and a group with PSV ratios between 2.5 and 4.0 in whom angiography was to be performed to determine clinical management on the basis of the stenosis severity. This algorithm had a positive predictive value of 93% and a negative predictive value of 89%. In addition, it resulted in a reduction of the number of angiograms of 49% compared with a policy of angiographies in all patients with a PSV ratio > or = 2.5. CONCLUSIONS: The best criterion to identify a failing graft is the PSV ratio. With a two-parameter algorithm for vein graft surveillance, the incidence of unnecessary revisions and of missed high-grade lesions was acceptably low, whereas the number of angiograms was reduced by one half. 相似文献
95.
96.
PM Sutaria M Ohebshalom TA McCaffrey ED Vaughan D Felsen 《Canadian Metallurgical Quarterly》1998,62(21):1965-1972
Transforming growth factor-beta (TGF-beta) is a profibrotic cytokine which has been implicated in the renal fibrosis which follows unilateral ureteral obstruction (UUO) in the rat. TGF-beta receptor type I (TGF-RI) and TGF-beta receptor type II (TGF-RII) are part of the complex which mediates the response to TGF-beta. We sought to determine if TGF-RI and TGF-RII are found in the kidney, and if their expression is changed as a result of UUO. Polymerase chain reaction (PCR) was used to determine expression of mRNA for TGF-RI and TGF-RII in the kidney. Immunoperoxidase was used to localize and quantify the expression of these receptors at 3, 7, 14, 21 and 28 days after UUO, and in sham-operated animals. Expression of mRNA for TGF-RI and TGF-RII was demonstrated in sham operated, obstructed and contralateral unobstructed kidneys using PCR. Using immunoperoxidase, a uniform distribution of TGF-RI and TGF-RII was found in cortical tubules of sham operated kidneys, whereas medullary tubules showed a patchy TGF-RI distribution and no TGF-RII staining. After UUO, an increased tubular expression of TGF-RI and TGF-RII was noted in both obstructed and contralateral kidneys compared to sham operated kidneys. No staining for either TGF-RI or TGF-RII was noted in glomeruli, vasculature or interstitial cells. TGF-beta receptors I and II were found exclusively in renal tubules and were shown to increase in both the obstructed and contralateral kidneys relative to sham operated animals. Upregulation of TGF-beta receptors in both kidneys suggests that TGF-beta may contribute to the fibrotic response in the obstructed kidney and the hypertrophic response of the contralateral kidney. 相似文献
97.
ED Kramer RJ Packer J Ginsberg S Goldman S Thompson LA Bayer V Shen R Harris S Khan JL Finlay 《Canadian Metallurgical Quarterly》1997,27(5):230-237
Acute neurologic complications occurred 103 times in 50 (54%) of 92 patients (primarily children) treated with high-dose chemotherapy and autologous bone marrow rescue for primary central nervous tumors. Different types of neurologic compromise occurred during the chemotherapy infusion as compared to the first 100 days after the chemotherapy and the greater-than-100-day time period. The causes of the neurologic compromise were also time sensitive. BACKGROUND: Results of treatment for children with primary brain tumors using high-dose chemotherapy with autologous marrow rescue (ABMR) have been encouraging. However, the neurotoxicity associated with this technique remains a major concern. We reviewed the records of 92 patients who underwent ABMR for malignant brain tumors between 1986 and 1992 for the occurrence and timing of acute neurologic dysfunction (AND). METHODS: Individual investigators at the participating institutions retrospectively completed standardized forms on each patient. The manner in which the distribution of AND versus time of treatment emerged led to the establishment of distinct time periods for data analysis and discussion. The pre-ABMR period included those events that occurred during the chemotherapy infusion, the early posttreatment period included the first 100 days following bone marrow rescue, and the late posttreatment period was greater than 100 days following bone marrow rescue. RESULTS: Fifty patients (54%) had 103 episodes of AND. AND included encephalopathies with or without hallucinations or coma (32), seizures (23), headaches (9), ataxia-tremor-dysarthria syndrome (7), anorexia and nausea syndrome (7) and others (25). During the chemotherapy infusion, encephalopathies and seizures were most common. Hallucinations occurred primarily related to drug infusion, while encephalopathies without hallucinations were usually due to demonstrable dysmetabolic states. In the 100 days following ABMR, dysmetabolic states and iatrogenic factors caused 45% and progressive disease caused 33% of AND. Greater than 100 days from ABMR, progressive disease caused 55% of AND; 7 patients were noted to develop chronic anorexia and nausea of unclear etiology. The occurrence of neurologic compromise was not related to the chemotherapy regimens, tumor histology, tumor location, patient age, prior treatment, or the amount of tumor at time of treatment. Dexamethasone use was the only clinical factor associated with AND (p < 0.004). CONCLUSIONS: The cause of AND was definable for 95% of instances that occurred within 100 days of ABMR. Early AND was often iatrogenic and reversible. The greater the time from ABMR the more likely AND was due to progressive disease. Clinical factors could not predict the occurrence of AND as only the concurrent use of dexamethasone at the time of treatment proved significant. Although frequent, AND should not be considered a limiting toxicity of this approach or preclude the use of this technique. 相似文献
98.
ADP-ribosylation factor 5 (ARF5) is a member of the ARF gene family. The ARF proteins stimulate the in vitro ADP-ribosyltransferase activity of cholera toxin and appear to play a role in vesicular trafficking in vivo. We have mapped ARF5, one of the six known mammalian ARF genes, to a well-defined yeast artificial chromosome contig on human chromosome 7q31.3. In addition, we have isolated and sequenced an approximately 3.2-kb genomic segment that contains the entire ARF5 coding region, revealing the complete intron-exon structure of the gene. With six coding exons and five introns, the genomic structure of ARF5 is unique among the mammalian ARF genes and provides insight about the evolutionary history of this ancient gene family. 相似文献
99.
PR Freund TA Bowdle KL Posner ED Kharasch VD Burkhart 《Canadian Metallurgical Quarterly》1997,87(5):1044-1049
BACKGROUND: Anesthetic drug expenditures have been a focus of cost-containment efforts. The aim of this study was to determine whether expenditures for neuromuscular-blocking agents could be reduced without compromising outcome, and to determine whether such a cost-effective pattern of neuromuscular blocker use could be sustained. METHODS: Education, practice guidelines, and paperwork barriers were used to persuade anesthesiologists to substitute low-cost neuromuscular-blocking drugs (pancuronium or a metocurine-pancuronium combination) for a more costly neuromuscular-blocking drug (vecuronium). Neuromuscular-blocking drug use in all patients during a historical control period (6 months; n = 4,804) was compared with that during two consecutive 1-yr periods of intervention (n = 9,761/n = 10,695). Expenditures for vecuronium and for all neuromuscular-blocking drugs were compared for the control and intervention periods. The rate of complications related to neuromuscular-blocking drugs was determined by an ongoing continuous quality improvement program. RESULTS: Vecuronium use decreased by 76% during the first and second yr of intervention, compared with the historical period (P < 0.01). The cost of neuromuscular-blocking drugs decreased by 31% (P < 0.01) and 47% (P < 0.01) for the first and second yr, respectively. The complication rate related to neuromuscular-blocking drugs was 0.081% in the historical period and 0.11% and 0.093% during the intervention periods (P = 0.29 and 0.41). CONCLUSION: Practice guidelines, education, and paperwork barriers used together substantially reduced the expenditures for neuromuscular-blocking drugs for 2 yr without adversely affecting clinical outcome. 相似文献
100.
JM Townes R Quick OY Gonzales M Linares E Damiani CA Bopp SP Wahlquist LC Hutwagner E Hanover ED Mintz RV Tauxe 《Canadian Metallurgical Quarterly》1997,175(6):1527-1530
In Bolivia, few data are available to guide empiric therapy for bloody diarrhea. A study was conducted between December 1994 and April 1995 to identify organisms causing bloody diarrhea in Bolivian children. Rectal swabs from children <5 years old with bloody diarrhea were examined for Salmonella, Shigella, and Campylobacter organisms; fecal specimens were examined for Entamoeba histolytica. A bacterial pathogen was identified in specimens from 55 patients (41%). Shigella organisms were found in 39 specimens (29%); 37 isolates (95%) were resistant to ampicillin, 35 (90%) to trimethoprim-sulfamethoxazole, and 24 (62%) to chloramphenicol, but all were susceptible to nalidixic acid. Only 1 of 133 stool specimens contained E. histolytica trophozoites. Multidrug-resistant Shigella species are a frequent cause of bloody diarrhea in Bolivian children; E. histolytica is uncommon. Clinical predictors described in this study may help identify patients most likely to have Shigella infection. Laboratory surveillance is essential to monitor antimicrobial resistance and guide empiric treatment. 相似文献