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81.
Y Ziv VW Fazio SA Strong JR Oakley JW Milsom IC Lavery 《Canadian Metallurgical Quarterly》1994,1(6):512-515
BACKGROUND: The association between mucosal ulcerative colitis (MUC) and adenocarcinoma is well established. METHODS: Records of patients who had undergone restorative proctocolectomy with ileal pouch-anal anastomosis (IPAA) from 1983 through 1992 were examined. Of these, 604 had MUC and 27 (4.3%) had MUC with coexisting cancer. Patients were surveyed annually for recurrent disease. Pouch function and quality of life were evaluated with a questionnaire and physical examination. RESULTS: The duration of disease was longer (p = 0.001) in patients with cancer (16.1 +/- 8.0 years) than in those without cancer (9.1 +/- 7.1 years), although the mean age at diagnosis of MUC was the same. Of the 27 patients, 20 had colon cancer and seven had rectal cancer. Multicentricity was found in seven (25.9%) patients. Using the TNM staging classification, 14 patients (51.8%) had stage 1 cancer, eight (29.6%) had stage 2, four (14.8%) had stage 3, and one (3.8%) had stage 4. The patient with stage 4 cancer died 5 months after surgery and was excluded from the follow-up analysis. During a mean follow-up time of 4.3 +/- 2.6 years, cancer recurred in two of the remaining 26 patients (7.7%). In one patient, a local recurrence was found 8 months after surgery, and distant metastases were found in the other patient 35 months after surgery. Both recurrences were in patients with colon cancer. Two of the 26 patients died; one death was related to cancer recurrence (3.8%). Pouch function is good to excellent in all surviving patients. CONCLUSIONS: Restorative proctocolectomy for patients with MUC and coexisting colorectal cancer can be performed with a favorable prognosis and function. It is appropriate for curative intent, given that an adequate margin without tumor is obtained. 相似文献
82.
The age-specific incidence of homosexually acquired HIV in Italy was examined, based on 3918 AIDS cases diagnosed by the end of 1994 and reported by the end of 1995 through the national surveillance system. Using a smoothed back-calculation analysis, the estimated median age at infection decreased over time, and HIV incidence among younger age groups peaked much later than among older age groups. These results support recent findings from other developed countries, and suggest that measures for preventing homosexual transmission of HIV are best targeted at younger age groups. 相似文献
83.
The first case of infection with Group B meningococcus in India is reported. The patient was a 4-month-old boy who presented with meningitis and died within 6 h of admission. Gram stain of CSF showed meningococci and latex particle agglutination test on CSF was strongly positive for Neisseria meningitidis serogroup B. The CSF was also positive for meningococcus by polymerase chain reaction using primers NM1 and NM6, which amplify a 650 bp region of the dihydropteroate synthase (dhps) gene of N. meningitidis. 相似文献
84.
JP Sullivan D Donnelly-Roberts CA Briggs DJ Anderson M Gopalakrishnan IC Xue M Piattoni-Kaplan E Molinari JE Campbell DG McKenna DE Gunn NH Lin KB Ryther Y He MW Holladay S Wonnacott M Williams SP Arneric 《Canadian Metallurgical Quarterly》1997,283(1):235-246
Lactate dehydrogenase from the malarial parasite Plasmodium falciparum has many amino acid residues that are unique compared to any other known lactate dehydrogenase. This includes residues that define the substrate and cofactor binding sites. Nevertheless, parasite lactate dehydrogenase exhibits high specificity for pyruvic acid, even more restricted than the specificity of human lactate dehydrogenases M4 and H4. Parasite lactate dehydrogenase exhibits high catalytic efficiency in the reduction of pyruvate, kcat/Km = 9.0 x 10(8) min(-1) M(-1). Parasite lactate dehydrogenase also exhibits similar cofactor specificity to the human isoforms in the oxidation of L-lactate with NAD+ and with a series of NAD+ analogs, suggesting a similar cofactor binding environment in spite of the numerous amino acid differences. Parasite lactate dehydrogenase exhibits an enhanced kcat with the analog 3-acetylpyridine adenine dinucleotide (APAD+) whereas the human isoforms exhibit a lower kcat. This differential response to APAD+ provides the kinetic basis for the enzyme-based detection of malarial parasites. A series of inhibitors structurally related to the natural product gossypol were shown to be competitive inhibitors of the binding of NADH. Slight changes in structure produced marked changes in selectivity of inhibition of lactate dehydrogenase. 7-p-Trifluoromethylbenzyl-8-deoxyhemigossylic acid inhibited parasite lactate dehydrogenase, Ki = 0.2 microM, which was 65- and 400-fold tighter binding compared to the M4 and H4 isoforms of human lactate dehydrogenase. The results suggest that the cofactor site of parasite lactate dehydrogenase may be a potential target for structure-based drug design. 相似文献
85.
The discovery of circulating autoantibodies to neutrophil granule proteins (ANCA), which are present in a high proportion of patients with vasculitis, has revitalised both clinical and experimental research in this area. Although their antigen specificities and strong association with vasculitic diseases have now been established, the role of ANCA in the disease process is uncertain. This review is a brief outline of some of the clinical associations of ANCA, and describes interesting new avenues being taken in recent research which may provide an insight into how ANCA may contribute to vascular damage in patients with vasculitis. 相似文献
86.
IC van Oosterhout 《Canadian Metallurgical Quarterly》1997,122(24):714-716
87.
Y Büyüka?ik B Soylu AR Soylu OI Ozcebe S Canbakan IC Haznedaro?lu S Kirazli Y Ba?er SV Dündar 《Canadian Metallurgical Quarterly》1998,12(6):1375-1379
Platelets have been suggested to play a role in the inflammatory response, including defence against bacteria. The aims of this study were to determine in vivo platelet activity during the clinical course of pulmonary tuberculosis and to investigate whether or not there is a correlation between the magnitude of platelet activation and the extent of the pulmonary disease. T-lymphocyte activity was also analysed in the patients. Platelet factor-4 (PF4) and soluble interleukin-2 receptor-alpha (sIL-2Ralpha) concentrations were used as markers of platelet and T-lymphocyte activation, respectively. Twenty-five patients with pulmonary tuberculosis were studied. Fifteen healthy subjects served as a control group. The levels of both sIL-2Ralpha (3,000+/-1,948 pg x mL(-1)) and PF4 (103.1+/-6.7 IU x mL(-1)) were significantly higher in the patients with tuberculosis than in the control group (984+/-360 pg x mL(-1) and 78.2+/-23.9 IU x mL(-1), respectively) (Mann-Whitney U-test, p<0.001 for both comparisons). The plasma PF4 levels were found to be well correlated with the extent of pulmonary lesions on chest radiography (the Spearman's bivariate correlation analysis, r=0.65, p<0.001). However, sIL-2Ralpha concentrations did not correlate with the extent of disease. In conclusion, it has been suggested that platelet and T-lymphocyte activation occurs during pulmonary tuberculosis. The good correlation between platelet activation and the extent of pulmonary tuberculosis might be ascribed to a pathophysiological role of platelets in pulmonary tuberculosis. 相似文献
88.
89.
A Kawashima CM Sandler IC Boridy N Takahashi GS Benson SM Goldman 《Canadian Metallurgical Quarterly》1997,168(4):997-1000
OBJECTIVE: The tissue rim sign-a rim or halo of soft-tissue attenuation seen around the circumference of an intraureteral calculus on unenhanced axial CT-has been described as useful in differentiating ureteral calculi from extraurinary abdominal or pelvic calcifications. The purpose of this study was to determine the prevalence of the tissue rim sign in patients with ureterolithiasis and extraurinary calcifications and to determine the relationship between the tissue rim sign, the size of a calculus, and the degree of urinary obstruction. MATERIALS AND METHODS: Unenhanced helical CT studies followed by excretory urography were obtained in 59 patients with suspected acute ureterolithiasis. Each calcification along the expected course of the ureter seen on axial CT scans was categorized as a ureteral calculus or as an extraurinary calcification. Each categorization was based on CT, urographic, and clinical findings and the presence or absence of a tissue rim sign. When the outer wall of the ureter could not be seen because there was no clear fat plane at the level of the calcification on CT, the sign was categorized as "indeterminate." The size of the calculus was measured on CT, and the degree of urinary obstruction was estimated on the basis of the urograms. RESULTS: Thirty-two patients each had a single ureteral calculus. Of these patients, CT revealed a positive tissue rim sign in 16 patients (50%), was negative in five patients (16%), and was indeterminate in 11 patients (34%). In addition, we saw 57 extraurinary calcifications in 18 patients (11 patients with ureteral calculi and seven patients without ureteral calculi). None of the 57 extraurinary calcifications was associated with a positive tissue rim sign. The tissue rim sign was negative in 39 (68%) of the 57 extraurinary calcifications and indeterminate in the remaining 18 (32%). Ureteral calculi with a negative tissue rim sign were larger than ureteral calculi with a positive tissue rim sign (p < .01). A high degree of obstruction was present in four of five patients with ureteral calculi for which CT showed a negative tissue rim sign. Conversely, six of 16 patients in whom CT revealed a positive tissue rim sign also had a high degree of obstruction. Therefore, no clear relationship was found between the degree of obstruction and the presence of a positive tissue rim sign. CONCLUSION: A positive tissue rim sign is specific for the diagnosis of ureterolithiasis. However, a negative tissue rim sign does not preclude such a diagnosis. The presence or absence of this tissue rim sign correlates with the size of a calculus but not with the degree of urinary obstruction. When CT reveals an indeterminate tissue rim sign, careful inspection for other CT findings, such as ipsilateral ureteral dilatation, perinephric edema, dilatation of the intrarenal collecting system, and renal swelling, is necessary. 相似文献
90.
The influence of type and size of nanoparticles on the thermal parameters of some magnetic nanofluids is investigated. Two types of carrier liquids (transformer oil and polypropylene glycol) were combined with two types of iron based magnetic nanoparticles (\(\hbox {Fe}_{3}\hbox {O}_{4}\) and \(\hbox {MnFe}_{2}\hbox {O}_{4})\). Different sizes (10 nm–80 nm) and shapes (spherical, octahedral or cubic) of nanoparticles were obtained depending on the oleic acid/oleylamine molar ratio, which drastically influences the nanocrystals growth rate. This influence is due to the different binding ability of the two stabilizers onto crystal facets. The average size of nanoparticles was 10 nm, 35 nm and 50 nm for \(\hbox {Fe}_{3}\hbox {O}_{4}\) and 10 nm, 20 nm and 80 nm for \(\hbox {MnFe}_{2}\hbox {O}_{4}\) at a concentration of 50 mg\({\cdot }\)ml\(^{-1}\) in all cases. The results obtained by PPE technique indicate that, at this concentration, the presence of the nanoparticles reduces the value of the thermal parameters of pure carrier liquids and both thermal diffusivity and effusivity decrease with increasing nanoparticles size, independently on the carrier liquid. The influence of the nanoparticles size is more pronounced for the thermal effusivity (relative change 24 %) compared with thermal diffusivity (relative change 7 %). 相似文献