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991.
DR Franken HS Bastiaan A Kidson P Wranz UF Habenicht 《Canadian Metallurgical Quarterly》1997,29(6):311-317
PURPOSE: The Octopus program Octosmart is able to classify visual fields into six classes. In the program a horizontal bar indicates these classes, and an indicator points to the most probable position, related to the measured pathology. The width of this dashed indicator shows the range of possible fluctuations in the measurement and, therefore, its precision. This study sets out to analyse the suitability of this display mode using other visual-field index data. METHODS: The visual fields of 83 glaucomatous eyes of 61 patients of various etiological groups and glaucoma suspects were studied for periods varying from 1 to 5 years in a retrospective study. All examinations were performed with the G1 Octopus program and analyzed with the Octosmart program. The statistical significance of linear trends of the visual-field indices, mean defect (MD) and corrected loss variance (CLV), and the class shown by the indicator (POI = position of indicator) were determined, and their regression coefficients were analyzed by means of a linear trend test as a function of time. RESULTS: Of the sample of 83 tested eyes, a total of 18 significant trends were recorded after five examinations. All visual-field indices showed a trend towards amelioration. CONCLUSIONS: The 18 significant trends observed must be attributed to perturbing long-term fluctuations and, despite their statistical significance, are of little clinical value. It is questionable whether an increased number of examinations per eye would have attenuated the threshold fluctuations sufficiently to make the change in field class more reliable. 相似文献
992.
JH Palma DR Almeida AC Carvalho JC Andrade E Buffolo 《Canadian Metallurgical Quarterly》1997,63(4):1081-1084
BACKGROUND: The surgical treatment of acute complicated type B aortic dissection continues to be a challenge and is still associated with high morbidity and mortality rates. METHODS: Seventy consecutive patients with an acute type B aortic dissection underwent an elephant trunk procedure through a median sternotomy during deep hypothermic circulatory arrest. An endoprosthesis that was 22 to 24 mm in diameter was inserted through an incision in the arch and held in place with only proximal sutures. RESULTS: The mean arrest time was 31.4 +/- 8.7 minutes, and it was possible to adequately position the endoluminal graft in every patient. The procedure was done in association with other procedures in 13 patients. There were six in-hospital deaths not related to the endoprosthesis, and four late deaths. Late reoperation was necessary in 6 patients to manage leakage at the proximal suture line. CONCLUSIONS: The insertion of an endoprosthesis through the arch for the management of a complicated acute type B dissection has several advantages over the conventional thoracotomy approach. The hospital mortality rate in this series of 70 patients was 20%, and the actuarial 5-year survival rate was 62.5%. We consider the elephant trunk procedure the treatment of choice in patients with type B acute dissections, regardless of whether the dissection is complicated or not. 相似文献
993.
994.
SM Walpole A Nicolaou GR Howell A Whittaker DR Bentley MT Ross JR Yates D Trump 《Canadian Metallurgical Quarterly》1997,44(3):300-308
Treatment of a skeletodental Class II vertical growth problem, combined with a severe arch length deficiency in both arches, presents a challenging orthodontic problem. This is the case report of a small-statured, 11-year, 10-month-old boy with a history of juvenile chronic arthritis and marked mandibular retrognathia who was treated with first premolar extractions in both arches. Unexpected favorable growth, with significant decrease of the mandibular plane angle over a long treatment period, provided a very satisfactory result. [This case report was presented to the American Board of Orthodontics in partial fulfillment of the requirements for the certification process.] 相似文献
995.
To elucidate the mechanisms that facilitate tolerance at the maternal-fetal interface, we are investigating the role of genes that are involved in peripheral self-tolerance in couples with idiopathic recurrent miscarriage. CTLA-4 is a negative regulator of T-cell proliferation and has been associated with human autoimmune disease. An AT(n) polymorphism in the 3'-untranslated region (UTR) of the human gene results in AT stretches that vary in length from 16 to 46 bp. We hypothesized that long stretches of AT repeats would result in mRNA instability, and reduced fetal survival in humans. We examined the transmission of AT(n) alleles in 60 couples with a history of > or = 3 unexplained spontaneous abortions to their 51liveborn children and 10 abortuses. The shorter allele was transmitted from heterozygous mothers to 26 of 35 liveborn children (chi2 = 8.3, P = 0.0040) and to three of nine aborted fetuses (chi2 = 1.0, P = 0.317). The shorter allele was transmitted from heterozygous fathers to 15 of 32 liveborn children (chi2 =0.12, P=0.726) and to five of eight aborted fetuses (chi2 = 0.5, P = 0.480). Furthermore, liveborn fetuses who inherited smaller alleles were more likely to represent the first successful pregnancy than liveborn fetuses who inherited larger maternal alleles (Pexact = 0.044) and fetuses of first pregnancies that inherited the smaller allele were significantly more likely to survive to term (Pexact = 0.0086). The preferential transmission of maternally-inherited shorter alleles to liveborn children, but random transmission of paternally-inherited alleles, suggests that CTLA-4 may be imprinted in humans and that this gene may play a role in inducing or maintaining tolerance at the maternal-fetal interface. 相似文献
996.
MD Norris SB Bordow PS Haber GM Marshall M Kavallaris J Madafiglio SL Cohn H Salwen ML Schmidt DR Hipfner SP Cole RG Deeley M Haber 《Canadian Metallurgical Quarterly》1997,33(12):1911-1916
We have recently shown that expression of the multidrug resistance-associated protein (MRP) gene is a powerful prognostic indicator in childhood neuroblastoma and have suggested that the MYCN oncogene may regulate MRP gene expression. To address this hypothesis, we have examined the relationship between MYCN and MRP gene expression in neuroblastoma tumours and cell lines. MYCN and MRP gene expression were highly correlated in 60 primary untreated tumours both with (P = 0.01) and without MYCN gene amplification (P < 0.0001). Like MRP, high MYCN gene expression was significantly associated with reduced survival, both in the overall study population and in older children without MYCN gene amplification (relative hazards = 13.33 and 19.61, respectively). Inhibition of MYCN, through the introduction of MYCN antisense RNA constructs into human neuroblastoma cells in vitro, resulted in decreased MRP gene expression, determined both by RNA-PCR and Western analysis. The data are consistent with MYCN influencing neuroblastoma outcome by regulating MRP gene expression. 相似文献
997.
LS Dean CJ George GS Roubin ED Kennard DR Holmes SB King RE Vlietstra JW Moses D Kereiakes JP Carrozza SG Ellis JR Margolis KM Detre 《Canadian Metallurgical Quarterly》1997,29(5):934-940
OBJECTIVES: We sought to determine the in-hospital clinical outcome and angiographic results of patients prospectively entered into the National Heart, Lung, and Blood Institute/New Approaches to Coronary Intervention (NHLBI/NACI) Registry who received Gianturco-Roubin stents as an unplanned new device. BACKGROUND: Between August 1990 and March 1994, nine centers implanted Gianturco-Roubin flex stents as an unplanned new device in the initial treatment of 350 patients (389 lesions) who were prospectively enrolled in the NHLBI/NACI Registry. METHODS: Patients undergoing implantation of the Gianturco-Roubin flex stent were prospectively entered into the Gianturco-Roubin stent portion of the NHLBI/NACI Registry. Only subjects receiving the Gianturco-Roubin stent as a new device in an unplanned fashion are included. RESULTS: The mean age of the patient group was 61.8 years, and the majority of the patients were men. A history of percutaneous transluminal coronary angioplasty (PTCA) was present in 35.4% of the group, and 16.9% had previous coronary artery bypass graft surgery. Unstable angina was present in 67.7%. Double- or triple-vessel coronary artery disease was present in 55.4%, and the average ejection fraction was 58%. The presence of thrombus was noted in 7.3%, and 7.2% had moderate to severe tortuosity of the lesion. The angiographic success rate was 92%. Individual clinical sites reported that 66.3% of the stents were placed after suboptimal PTCA, 20.3% for abrupt closure and 13.4% for some other technical PTCA failure. Major in-hospital events occurred in 9.7% of patients, including death in 1.7%, Q wave myocardial infarction in 3.1% and emergency bypass surgery in 6%. Abrupt closure of a stented segment occurred in 3.1% of patients at a mean of 3.9 days. Cerebrovascular accident occurred in 0.3%, and transfusion was required in 10.6%. Vascular events with surgical repair occurred in 8.6% of patients. CONCLUSIONS: Despite these complications, the use of this device for the treatment of a failed or suboptimal PTCA result remains promising given the adverse outcome of abrupt closure with conventional (nonstent) treatment. 相似文献
998.
FO Fran?a LA Benvenuti HW Fan DR Dos Santos SH Hain FR Picchi-Martins JL Cardoso AS Kamiguti RD Theakston DA Warrell 《Canadian Metallurgical Quarterly》1994,87(5):269-282
In S?o Paulo State, Brazil, five males, aged between 8 and 64 years, were attacked by 'Africanized' honey bees (Apis mellifera scutellata). The estimated number of stings received by each patient ranged from > 200 to > 1000. All five were transferred to intensive care units in S?o Paulo City. Clinical features included intravascular haemolysis, respiratory distress with ARDS, hepatic dysfunction, rhabdomyolysis (with myoglobinaemia and myoglobinuria), hypertension and myocardial damage (perhaps explained by release of endogenous catecholamines by venom phospholipase A2 and mellitin), shock, coma, acute renal failure and bleeding. Laboratory findings included gross neutrophil leucocytosis, elevated serum enzymes [AST, ALT, LDH, CPK (predominantly CPK-MM)] and creatinine. Clotting times were slightly prolonged. Despite treatment with antihistamines, corticosteroids, bronchodilators, vasodilators, bicarbonate, mannitol and mechanical ventilation, three of the patients died between 22 and 71 h after the attacks, with histopathological features of ARDS, hepatocellular necrosis, acute tubular necrosis, focal subendocardial necrosis and disseminated intravascular coagulation. Whole bee venom and phospholipase A2 (PLA2) antigen concentrations were measured in serum and urine for the first time, using enzyme immunoassay. High venom and PLA2 concentrations were detected in serum and urine for more than 50 h after the stings in two fatal cases, in one of which the total circulating unbound whole venom was estimated at 27 mg, one hour after the attack. An antivenom should be developed to treat the increasing numbers of victims of mass attacks by Africanized 'killer' bees in USA, Middle and South America. 相似文献
999.
DW Ho PR Field WL Irving DR Packham AL Cunningham 《Canadian Metallurgical Quarterly》1993,31(12):3157-3164
Western blots (immunoblots) for the detection of immunoglobulin M (IgM) antibodies specific for herpes simplex virus type 1 (HSV-1) and HSV-2 in patients' sera were developed. The locations of the type-specific glycoprotein G (gpG-2) of HSV-2 (92- and 140-kDa forms) and glycoprotein C of HSV-1 (gpC-1), which carries mostly type-specific antigenic epitopes, were checked with specific monoclonal antibodies. Western blot assays for IgM antibody to gpC-1 or gpG-2 were performed after depletion of IgG by precipitation with anti-human IgG. In patients with primary HSV-2 genital infections, seroconversion of IgM and IgG antibodies to both the 92- and 140-kDa forms of gpG-2 was observed, although both antibodies appeared in convalescent-phase serum after the first week. IgM and IgG antibodies to low-molecular-size polypeptides (40 to 65 kDa) were the first antibodies observed in patients with primary infection, but these antibodies were cross-reactive with HSV-1 and HSV-2. However, in patients with recurrent HSV-2 infections, IgG antibodies to both forms of gpG-2 and the low-molecular-size polypeptides were found no matter how early after onset the patient was bled, and IgM to gpG-2 did not appear. In patients with nonprimary initial genital HSV-2 infections, IgG antibody to HSV-1 was demonstrated in the first serum specimen, and HSV-2-specific IgM was found in 39% of the serum specimens. Hence, the Western blot assay can be used to test for IgM antibody to gpG-2, allowing for the retrospective diagnosis of inital HSV-2 infections and its use as a supplementary test to the gpG-2 IgG enzyme-linked immunosorbent assays developed elsewhere. In contrast, IgM antibody to gpG-2 is not usually detected in patients with recurrent HSV-2 infections. 相似文献
1000.
DP Spence DR Graham J Ahmed K Rees MG Pearson PM Calverley 《Canadian Metallurgical Quarterly》1993,103(3):693-696
Cold air may worsen asthmatic bronchoconstriction but can lessen breathlessness in normal individuals. Patients with COPD sometimes report improvement in their dyspnea in cold weather. We examined the effect of breathing cold air on exercise tolerance and the perception of breathlessness in 19 patients with stable COPD (age [+/- SD], 63 +/- 6 years; FEV1, 0.99 +/- 0.28 L) in a randomized open study. Patients exercised on a cycle ergometer breathing either room or cold air (-13 degrees C), breathlessness being assessed by Borg scaling. Peak exercise performance improved when breathing cold air (mean +/- SE), 46 +/- 6 W compared with 37 +/- 7 W (p < 0.05) while end-exercise breathlessness fell from 4.6 +/- 0.4 compared with 4.1 +/- 0.5 (p < 0.05) when breathing cold air. End-exercise ETCO2 was higher breathing cold air (6.1 +/- 0.3 kPa compared with 5.5 +/- 0.3 kPa) (p < 0.005). There was no difference in breathlessness at equivalent levels of ventilation. Cold air reduces breathlessness in COPD, probably by inducing relative hypoventilation. 相似文献