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911.
GV Herdy VG Lopes ML Arag?o CA Pinto PA Tavares Júnior FB Azeredo PM Nascimento 《Canadian Metallurgical Quarterly》1998,71(2):121-126
New bisantrene analogues were synthesized, bearing one or two 4,5-dihydro-1H-imidazol-2-yl hydrazone side chains at positions 1,4 or 9 of the anthracene ring system. A 10-azabioisostere was also prepared. The position of substituents in structurally isomeric drugs modulates topoisomerase II poisoning and specificity, along with cytotoxicity. 相似文献
912.
913.
We describe the cases of an 18-year-old female and a 15-year-old male who developed severe anaphylaxis following contact of surgical wounds with the disinfectant Lavasept, containing polyhexanide, a polymerised form of chlorhexidine, during orthopaedic interventions. According to the manufacturer, this product is the only polyhexanide containing medical disinfectant, has recently been commercialised and is only available in Switzerland. One of the patients denied previous contact with this compound but both patients were previously exposed to chlorhexidine. Immediate-type hypersensitivity to polyhexanide was suggested by positive skin prick tests in the two patients and by negative skin tests in control individuals. Skin tests with chlorhexidine in the patients remained negative. We conclude that contact with the new disinfectant Lavasept can trigger anaphylactic reactions, even in the absence of previous history of exposure to this compound. It remains to be established whether this new disinfectant is a frequent anaphylactogen. 相似文献
914.
Frequency data for the STR system HumFGA were obtained from a North Italian population sample (Milano area) of 201 unrelated individuals. PCR products were detected by horizontal polyacrylamide gel electrophoresis and a total of 15 alleles were identified by side-by-side comparison with a commercially available sequenced allelic ladder. The observed genotype distribution showed no significant deviation from Hardy-Weinberg equilibrium. The high information content (discrimination power > 0.96, polymorphism information content > 0.84) render this system a useful tool in forensic routine casework both in criminal and paternity cases. 相似文献
915.
Three-dimensional reconstruction of the membranous vestibular labyrinth in the toadfish, Opsanus tau
Membranous vestibular labyrinths from the oyster toadfish, Opsanus tau, were fixed, dissected from the animal, stained, and embedded in rectangular blocks of clear histological resin. Photomicrographs of complete embedded labyrinths were taken from six orthogonal directions and used to construct three-dimensional (3D) geometrical models of the semicircular canals, ampullae, utricular vestibule and common crus. Membraneous ducts and ampullae were modeled using a set of cross-sectional elliptical curves laced together to generate curved tubular models of each structure. The ensemble of these curved tubes was used to generate a complete 3D reconstruction of the outside surface of the membranous labyrinth. When viewed from six orthogonal directions, reconstructions closely matched the embedded tissue. Dimensions of the reconstruction and histological sections were compared to measurements of fresh tissue taken from the same animals prior to fixation and used to correct the reconstructions for tissue shrinkage. Results provide estimates of the endolymphatic volumes, local cross-sectional areas and elliptical eccentricities as well as 3D orientations of the geometric canal planes relative to the skull. Ten micrometer histological sections of the material were also prepared to measure wall thickness in various regions of the labyrinth. 相似文献
916.
Although the discriminative properties of cocaine have been examined extensively in rats, and to a lesser extent in other species, there are currently no reports on cocaine discrimination by mice. In one of our experiments, C57BL/6 (C57) mice acquired cocaine discrimination (10 mg/kg training dose) and exhibited dose responsive generalization to lower doses of the drug, which was similar to previous reports using rats. In addition, mazindol, a general monoamine uptake inhibitor similar to cocaine, and nomifensine, which is relatively specific for the dopamine transporter, substituted completely for cocaine, as described for rats. In contrast, there was little substitution evidenced by monoamine uptake inhibitors relatively specific for the norepinephrine transporter (nisoxetine) or for the serotonin transporter (fluoxetine), or by the local anesthetics procaine or lidocaine. In our second experiment, neither cocaine nor mazindol substituted for procaine in animals trained to discriminate the local anesthetic (100 mg/kg) although lidocaine substituted completely for the procaine cue. These experiments emphasize the importance of the dopamine transporter in mediating the discriminative stimulus effects of cocaine in C57 mice. The lack of cross generalization between cocaine and procaine suggests that the anesthetic properties of cocaine contribute little toward its discrimination by this mouse strain. 相似文献
917.
D Ardissino PA Merlini R Ari?ns R Coppola E Bramucci PM Mannucci 《Canadian Metallurgical Quarterly》1997,349(9054):769-771
BACKGROUND: Coronary atherosclerotic-plaque thrombosis is a key event in the pathogenesis of unstable angina and myocardial infarction. Although plaque rupture or fissuring frequently occurs in atherosclerosis, only a small proportion of ruptured plaques develop thromboses. METHODS: Tissue-factor antigen and activity were measured in atherectomy samples from 50 consecutive patients with coronary artery disease (stable angina n = 19, unstable angina n = 24, and myocardial infarction n = 7). FINDINGS: Median tissue-factor antigen and activity concentrations were significantly higher in plaques from patients with unstable angina and myocardial infarction than in those from patients with stable angina (antigen: 66.1 pg/mg [interquartile range 43.8-82.5] vs 32.4 pg/mg [9.8-43.4], p = 0.0001; activity: 0.22 mU/mg [0.17-0.41] vs 0.13 mU/mg [0.05-0.16], p = 0.0004). INTERPRETATION: Tissue-factor, an initiator of the coagulation cascade, may account for the different thrombotic responses to the rupture of human coronary atherosclerotic plaques. 相似文献
918.
PA Dremsek K Gindl P Voitl R Strobl E Hafner W Geissler W Hruby M Sacher 《Canadian Metallurgical Quarterly》1997,168(4):1017-1019
OBJECTIVE: Pre- and postnatal pyelectasis detected by sonographic screening is of questionable pathologic importance. Therefore, we defined the natural course and diagnostic value of renal pelvis diameter (RPD) during fetal life and the neonatal period as such dilatation was revealed on routine sonography. MATERIALS AND METHODS: Routine sonography in pregnant women was obtained between gestational weeks 22 and 30. Sonograms were obtained for 1021 fetuses, of which 15 could not be followed up as neonates. The remaining 1006 fetuses also underwent neonatal sonography. All neonates with an RPD larger than 5 mm were followed up sonographically. Neonates with an RPD larger than 9 mm or persistent widening (> 5-9 mm) were examined by voiding cystourethrogram, radionuclide renogram, or both. RESULTS: Thirty fetuses (3%) had an RPD larger than 5 mm. Nine of these fetuses also had an RPD larger than 5 mm as neonates. Of these nine neonates, one had bilateral grade II vesicoureteric reflux (VUR) and two had urinary tract obstructions (one posterior urethral valve and one ureteropelvic junction obstruction). Forty-nine neonates whose results on fetal sonograms had been normal showed an RPD larger than 5 mm on neonatal sonograms. Grade III VUR was found in one boy, and ureteropelvic junction obstruction was found in two boys. The kidneys of 54 neonates who showed an RPD larger than 5 mm without urinary tract obstruction were followed up until an RPD of 0-5 mm was evident. RPD normalized within 1 year of birth, whether VUR was present or not. Symptomatic urinary tract infection was diagnosed in 17 infants who had no renal pelvis dilatation seen on pre-or postnatal screening during the observation period. Seven of the 17 neonates had VUR. Conversely, none of the infants with pre- postnatal dilatation presented with symptomatic urinary tract infection. However, in one neonate an asymptomatic urinary tract infection without VUR was diagnosed by routine urinalysis. CONCLUSION: In our study, we linked renal pelvis dilatation on pre- and postnatal sonograms to obstructive uropathies rather than to vesicoureteric reflux. Prenatal sonography proved less sensitive than postnatal sonography in revealing obstructive uropathies. An RPD smaller than 10 mm on neonatal sonography was of no pathologic significance because renal collecting systems normalized spontaneously in all infants within 1 year of birth. These neonates and infants had no significant risk for urinary tract infection and did not need further evaluation. 相似文献
919.
SL Parsons SA Watson HM Collins NR Griffin PA Clarke RJ Steele 《Canadian Metallurgical Quarterly》1998,78(11):1495-1502
The aim of the study was to investigate expression of the active and inactive gelatinases (MMP-2 and -9) in colorectal neoplasia and gastric cancer compared with normal mucosa. A total of 53 colorectal cancers and corresponding normal mucosa were studied using gelatin zymography as well as 15 colorectal adenomas and 13 gastric cancers with corresponding normal mucosa. Overexpression of all the gelatinases occurs in both colorectal and gastric cancer, with activation of MMP-2 appearing to be a feature of the malignant phenotype. Overexpression of MMP-9 occurs in colorectal adenomas. The gelatinases are overexpressed in gastrointestinal neoplasia, suggesting that these enzymes may have an important role in tumour invasion and metastasis. 相似文献
920.
Boron trifluoride monohydrate, an inexpensive superacid, was found to be an efficient catalyst for thioacetalization. 相似文献