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排序方式: 共有445条查询结果,搜索用时 15 毫秒
1.
Ultrastructural analysis of pancreatic acinar cells from mice fed on genetically modified soybean
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Malatesta M Caporaloni C Rossi L Battistelli S Rocchi MB Tonucci F Gazzanelli G 《Journal of anatomy》2002,201(5):409-415
No direct evidence that genetically modified (GM) food may represent a possible danger for health has been reported so far; however, the scientific literature in this field is quite poor. Therefore, we investigated the possible effects of a diet containing GM soybean on mouse exocrine pancreas by means of ultrastructural, morphometrical and immunocytochemical analyses. Our observations demonstrate that, although no structural modification occurs in pancreatic acinar cells of mice fed on GM soybean, quantitative changes of some cellular constituents take place in comparison to control animals. In particular, a diet containing significant amount of GM food seems to influence the zymogen synthesis and processing. 相似文献
2.
Accelerated solvent extraction and liquid chromatography-tandem mass spectrometry quantitation of corticosteroid residues in bovine liver 总被引:1,自引:0,他引:1
Draisci R Marchiafava C Palleschi L Cammarata P Cavalli S 《Journal of chromatography. B, Biomedical sciences and applications》2001,753(2):217-223
A new method for the rapid extraction and unequivocal confirmation of two highly potent fluorinated synthetic corticosteroids, dexamethasone and its beta-epimer betamethasone, in bovine liver was developed. Flumethasone was used as internal standard. An extraction procedure using an accelerated solvent extraction system was employed for the isolation of the analytes in liver samples. The procedure was highly automated, including defatting and extraction steps, sequentially carried out under 1.0 x 10(4) kPa in about 35 min. The extracts were then directly analysed by tandem mass spectrometry with on-line liquid chromatography. The analytes were ionised in a heated nebulizer interface operating in the negative ion mode where the molecular related ions [M-H-CH2O]- were generated for each analyte, at m/z 361 for betamethasone and dexamethasone and at m/z 379 for flumethasone. They served as precursor ions for collision-induced dissociation and three diagnostic product ions for the drugs were identified to carry out analyte confirmation by selected reaction monitoring. Assessment of recovery, specificity and precision for betamethasone, dexamethasone and flumethasone proved the method suitable for confirmatory purposes. The limit of quantification of betamethasone and dexamethasone in liver tissue was 1.0 microg/kg. 相似文献
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4.
Multicenter evaluation of AMPLICOR and automated COBAS AMPLICOR CT/NG tests for Neisseria gonorrhoeae 总被引:7,自引:0,他引:7
Martin DH Cammarata C Van Der Pol B Jones RB Quinn TC Gaydos CA Crotchfelt K Schachter J Moncada J Jungkind D Turner B Peyton C 《Journal of clinical microbiology》2000,38(10):3544-3549
The fully automated COBAS AMPLICOR CT/NG and semiautomated AMPLICOR CT/NG tests were evaluated in a multicenter trial for their ability to detect Neisseria gonorrhoeae infections. Test performance compared to that of culturing was evaluated for 2,192 matched endocervical swab and urine specimens obtained from women and for 1, 981 matched urethral swab and urine specimens obtained from men. Culture-negative, PCR-positive specimens that tested positive in a confirmatory PCR test for an alternative target sequence within the N. gonorrhoeae 16S rRNA gene were considered to be true positives. The overall prevalences of gonorrhea were 6.6% in women and 20.1% in men. The COBAS AMPLICOR and AMPLICOR formats yielded concordant results for 98.8% of the specimens and exhibited virtually identical sensitivities and specificities. The results that follow are for the COBAS AMPLICOR format. With the infected patient as the reference standard, the resolved sensitivities of PCR were 92.4% for endocervical swab specimens and 64.8% for female urine specimens. There were no significant differences in these rates between women with and without symptoms. Among symptomatic men, COBAS AMPLICOR sensitivities were 94.1% for urine and 98.1% for urethral swabs; for asymptomatic men, the results were 42.3 and 73.1%, respectively. In comparison, the sensitivities of culturing were 84.8% for endocervical specimens, 92.7% for symptomatic male urethral specimens, and only 46.2% for urethral specimens obtained from asymptomatic men. When PCR results were analyzed as if only a single test had been performed on a single specimen type, the resolved sensitivity was always higher. The resolved specificities of PCR were 99.5% for endocervical swab specimens, 99.8% for female urine specimens, 98.9% for male urethral swab specimens, and 99.9% for male urine specimens. The internal control revealed that 2.1% of specimens were inhibitory when initially tested. Nevertheless, valid results were obtained for 99.2% of specimens because 60.0% of the inhibitory specimens were not inhibitory when a second aliquot was tested. The COBAS AMPLICOR CT/NG test for N. gonorrhoeae exhibited high sensitivity and specificity with urethral swab and urine specimens from men and endocervical swab specimens from women and thus is well suited for diagnosing and screening for N. gonorrhoeae infection. 相似文献
5.
Cristina Lasheras Angeles M. Patterson Carmen Casado Serafina Fernandez 《Experimental aging research》2013,39(3):257-270
An inverse relation between education and health has been reported, suggesting the importance of examining the underlying mechanism of this association. We examined whether cardiovascular risk factors, diet, and indicators of quality of life (mood, self-perceived health, social relationships, self-rated sensory, and dental adequacy) vary according to educational level among 352 old people (65–95 years old) in the city of Oviedo (Northern Spain). Lower educational level (LE) was associated with unhappiness, poor social relationships, poor self-assessed health, and sensory, and masticatory problems. LE elderly consumed less vegetables and meat products and more carbohydrates. LE women had a lower contribution of proteins and lipids to their total energy intake as well as a lower vitamin A intake. Except for hypercholesterolemia, no differences 相似文献
6.
Background : In most vertebrates, the segmentation of the paraxial mesoderm involves the formation of metameric units called somites through a mesenchymal‐epithelial transition. However, this process is different in Xenopus laevis because it does not form an epithelial somite. Xenopus somitogenesis is characterized by a complex cells rearrangement that requires the coordinated regulation of cell shape, adhesion, and motility. The molecular mechanisms that control these cell behaviors underlying somite formation are little known. Although the Paraxis has been implicated in the epithelialization of somite in chick and mouse, its role in Xenopus somite morphogenesis has not been determined. Results : Using a morpholino and hormone‐inducible construction approaches, we showed that both gain and loss of function of paraxis affect somite elongation, rotation and alignment, causing a severe disorganization of somitic tissue. We further found that depletion or overexpression of paraxis in the somite led to the downregulation or upregulation, respectively, of cell adhesion expression markers. Finally, we demonstrated that paraxis is necessary for the proper expression of myotomal and sclerotomal differentiation markers. Conclusions : Our results demonstrate that paraxis regulates the cell rearrangements that take place during the somitogenesis of Xenopus by regulating cell adhesion. Furthermore, paraxis is also required for somite differentiation. Developmental Dynamics 244:973–987, 2015. © 2015 Wiley Periodicals, Inc. 相似文献
7.
Chiara Lazzeri Serafina Valente Gian Franco Gensini 《Current heart failure reports》2014,11(3):241-245
In patients with acute heart failure (AHF) syndromes, little data are so far available on the relation between glucose values and insulin resistance and mortality, both in the short and long term. The present review is aimed at summarizing available evidence on the prognostic role of hyperglycemia in acute heart failure syndromes. Despite the fact that glucose values are widely measured, inexpensive, and easy to interpret, hyperglycemia in AHF patients still appears to be (or at least to have been) a neglected factor. Scarce information is available on incidence of admission hyperglycemia (especially in nondiabetic AHF patients) and data on in-hospital and discharge glucose values are lacking. Overall, the scarcity of data and the unanswered questions conjure up the need for trials investigating the clinical and prognostic role of glucose abnormalities (hyperglycemia and acute insulin resistance) on admission and during hospital stay in AHF patients. Preliminary evidence suggests that hyperglycemia is an important prognostic factor in AHF; however, whether targeting hyperglycemia via an aggressive versus permissive glycemic management strategy influences AHF outcomes remains unknown. 相似文献
8.
Valente S Lazzeri C Crudeli E Chiostri M Giglioli C Bernardo P Gensini GF 《Clinical cardiology》2012,35(4):200-204
Background:
The intraaortic balloon pump (IABP) is the most commonly used mechanical circulatory support for patients with acute coronary syndromes and cardiogenic shock. Nevertheless, IABP‐related complications are still frequent and associated with a poor prognosis.Hypothesis:
To prospectively assess the incidence and predictors of complications in patients treated with IABP.Methods:
A total of 481 patients treated with IABP were prospectively enrolled in our registry (the Florence Registry). At multivariable logistic regression analysis the following variables were independent predictors for complications (when adjusted for age >75 years, eGFR and time length of IABP support): use of inotropes (OR 2.450, P < 0.017), nadir platelet count (1000/µL step; OR 0.990, P < 0.001), admission lactate (OR 1.175, P = 0.003). Nadir platelet count showed a negative correlation with length of time of IABP implantation (r?0.31; P < 0.001). A nadir platelet count cutoff value of less than 120,000 was identified using a receiver operating characteristic (ROC) curve for the development of complications (area under the curve [AUC] 0.70; P < 0.001).Results:
Complications were observed in the 13.1%, among whom 33 of 63 showed major bleeding. The incidence of complications was higher in patients aged >75 years (P = 0.015) and in those who had an IABP implanted for more than 24 hours (P = 0.001). Patients with complications showed an in Intensive Cardiac Care Unit (ICCU) mortality higher than patients who did not (44.4% vs 17.2%, P < 0.001).Conclusions:
In consecutive patients treated with IABP support, the degree of hemodynamic impairment and the decrease in platelet count were independent predictors of complications, whose development was associated with higher in‐ICCU mortality. © 2011 Wiley Periodicals, Inc. The authors have no funding, financial relationships, or conflicts of interest to disclose.9.
10.