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81.
Elena Albanell Josefina Plaixats Alfred Ferret Lluis Bosch Francesc Casaas 《Journal of the science of food and agriculture》1995,69(3):269-273
Near-infrared reflectance spectroscopy (NIRS) analysis was investigated as a means of predicting quality parameters in semi-exotic maize stover. These parameters included crude protein (CP), neutral detergent fibre, acid detergent fibre and in vitro dry matter digestibility (IVDMD). Samples of semi-exotic maize stover were collected during three growing seasons (1989, 1990, 1991) from three locations in Catalonia, Spain. Calibration equations were obtained by multiple linear regression of conventional laboratory values on NIRS data from 84 samples and verified with 20 additional samples. Separate NIRS calibration were developed also within year (1989 and 1990, respectively). A Bran + Luebbe InfraAnalyzer model 450 was used for the study. In the multi-year calibration the coefficients of squared multiple correlation (R2) ranged from 0–81 for IVDMD to 0–92 for CP and the standard errors of calibration (SEC) ranged from 0–35 for CP to 1–46 for IVDMD. The study showed that NIRS analysis can be used to evaluate the quality of semi-exotic maize in breeding programmes. 相似文献
82.
Soemmerring’s Rings Developed around IOLs,in Human Donor Eyes,Can Present Internal Transparent Areas
Justin Christopher DAntin Francesc Tresserra Rafael I. Barraquer Ralph Michael 《International journal of molecular sciences》2022,23(21)
Soemmerring’s rings consist of a ring of lens epithelial derived cells that grow along the periphery of an aphakic lens capsule, or around an intraocular lens. These rings when visualized frontally, appear opaque, however, in some cases the cells that compose these rings are organized in the same fashion as those in normal transparent adult lenses. Thus, our purpose was to test whether any part of the adult Soemmerring’s ring could be transparent and how this related to morphological factors. To study this, 16 Soemmerring’s rings were extracted from donor eye globes. After imaging, they were thickly sectioned sagittally in order to analyze the degrees of transparency of different areas. All samples were also histologically analyzed using alpha smooth muscle actin, Vimentin, wheat germ agglutinin and DAPI. Our results showed that many samples had some transparent areas, mostly towards the center of their cross-section. Of the factors that we analyzed, only lens fiber organization at the bow region and an increased area of mature lens fiber cells had a significant relation to the degree of transparency at the center. Thus, we can conclude that as Soemmerring’s rings mature, they can develop organized and transparent areas of lens cells. 相似文献
83.
Laura Snchez-Bellver Andrea Frriz-Gordillo Marc Carrillo-Pz Laura Rabanal Francesc R. Garcia-Gonzalo Gemma Marfany 《International journal of molecular sciences》2022,23(20)
Proteins related to the ubiquitin-proteasome system play an important role during the differentiation and ciliogenesis of photoreceptor cells. Mutations in several genes involved in ubiquitination and proteostasis have been identified as causative of inherited retinal dystrophies (IRDs) and ciliopathies. USP48 is a deubiquitinating enzyme whose role in the retina is still unexplored although previous studies indicate its relevance for neurosensory organs. In this work, we describe that a pool of endogenous USP48 localises to the basal body in retinal cells and provide data that supports the function of USP48 in the photoreceptor cilium. We also demonstrate that USP48 interacts with the IRD-associated proteins ARL3 and UNC119a, and stabilise their protein levels using different mechanisms. Our results suggest that USP48 may act in the regulation/stabilisation of key ciliary proteins for photoreceptor function, in the modulation of intracellular protein transport, and in ciliary trafficking to the photoreceptor outer segment. 相似文献
84.
Marcelo Arenas Jorge Pérez Juan Reutter Cristian Riveros 《The VLDB Journal The International Journal on Very Large Data Bases》2012,21(6):823-842
The inversion of schema mappings has been identified as one of the fundamental operators for the development of a general framework for metadata management. During the last few years, three alternative notions of inversion for schema mappings have been proposed (Fagin-inverse (Fagin, TODS 32(4), 25:1–25:53, 2007), quasi-inverse (Fagin et?al., TODS 33(2), 11:1–11:52, 2008), and maximum recovery (Arenas et?al., TODS 34(4), 22:1–22:48, 2009)). However, these notions lack some fundamental properties that limit their practical applicability: most of them are expressed in languages including features that are difficult to use in practice, some of these inverses are not guaranteed to exist for mappings specified with source-to-target tuple-generating dependencies (st-tgds), and it has been futile to search for a meaningful mapping language that is closed under any of these notions of inverse. In this paper, we develop a framework for the inversion of schema mappings that fulfills all of the above requirements. It is based on the notion of ${\mathcal{C}}$ -maximum recovery, for a query language ${\mathcal{C}}$ , a notion designed to generate inverse mappings that recover back only the information that can be retrieved with queries in ${\mathcal{C}}$ . By focusing on the language of conjunctive queries (CQ), we are able to find a mapping language that contains the class of st-tgds, is closed under CQ-maximum recovery, and for which the chase procedure can be used to exchange data efficiently. Furthermore, we show that our choices of inverse notion and mapping language are optimal, in the sense that choosing a more expressive inverse operator or mapping language causes the loss of these properties. 相似文献
85.
Compiler Verification has been identified as a vital process in the implementation of correct safety-critical systems. We extend here Hoare's refinement-algebra approach to compilation in order to include real-time languages in which processes interact asynchronously via communication queues. The existence of unique fixed-points is exploited to verify the implementation of crucial operators such as asynchronous input, delay and timeout. 相似文献
86.
S Le Bras F Miralles A Basmaciogullari P Czernichow R Scharfmann 《Canadian Metallurgical Quarterly》1998,47(8):1236-1242
Several investigators have postulated that soluble growth factors are involved in the early development of the pancreas. In many tissues in which soluble factors are implicated in development, these factors act on their target cells through tyrosine kinase receptors. Because we had some preliminary evidence that fibroblast growth factor receptors (FGFRs) were expressed in the early pancreas, we investigated the effect of fibroblast growth factors (FGFs) during embryonic pancreatic development. For that purpose, we first studied the distribution and the functionality of FGFRs during pancreatic organogenesis. FGFR1 and FGFR4 were shown to be expressed at a high level during early pancreatic development before embryonic day 16, their levels of expression decreasing thereafter. The functionality of FGFR was studied next. It was demonstrated in vitro that both FGF1 and FGF2 induce the expression of NGFI-A mRNA, a useful indicator of functional growth factor-signaling pathways. Finally, the effect of FGF2 on embryonic pancreatic epithelial cell proliferation was studied. It was shown that FGF2 induces the proliferation of pancreatic epithelial cells during embryonic life. Taken together, these data strongly suggest that FGFs are implicated in pancreatic development during embryonic life. 相似文献
87.
RB Arenas A Fichera D Mhoon F Michelassi 《Canadian Metallurgical Quarterly》1998,133(6):608-11; discussion 611-2
BACKGROUND: Total mesorectal excision has been advocated in conjunction with low anterior or abdominoperineal resection as the optimal surgical treatment for rectal cancer. It involves removal of the entire rectal mesentery as an intact unit and maximizes the likelihood of obtaining a negative circumferential margin. OBJECTIVES: To prospectively validate the efficacy of total mesorectal excision in obtaining locoregional control, to identify the perioperative factors influencing the selection of either a sphincter sparing or a sphincter ablating procedure, and to identify independent factors that may influence long-term prognosis in rectal cancers. SETTINGS: Tertiary referral center. PATIENTS: Seventy-three consecutive patients with rectal cancer located within 10 cm of the anal verge were treated from 1984 to 1997 by the senior author (F.M.). Sixty-five patients form the basis of our analysis after the exclusion of 7 patients who had their cancer removed transanally and 1 patient who had a permanent diverting stoma as the only procedure. RESULTS: Twenty-six patients underwent a sphincter ablating procedure; 39 underwent a sphincter sparing procedure. Operative mortality was 1.5%. Follow-up was complete in 64 patients (39+/-30 months; range, 3-126 months). Five-year actuarial survival rates were 88% for the 34 patients with stage I and II adenocarcinoma and 65% for the 22 patients with stage III adenocarcinoma. The local recurrence rate was 6.2% overall, but only 3.1% in the potentially curable group (stages I-III). When only patients who did not receive adjuvant chemoradiation therapy were considered (n=23), local recurrence rate was 8.3% overall and 0% in the potentially curable group. Tumor stage (P=.04) and vascular and/or lymphatic invasion (P=.002) were statistically significant in their association with survival. Circumferential lesions (P<.001), gross invasion of contiguous organs (P<.001) and distance from the anal verge of less than 5 cm (P=.01) were statistically significant in their association with the choice of a sphincter ablating procedure. CONCLUSIONS: This study confirms the efficacy of total mesorectal excision in minimizing locoregional recurrence rates and confirms the well-established prognostic value of stage and microinvasion. Moreover, it indicates that circumferential lesions, distance from anal verge, and gross invasion of contiguous organs are significant perioperative factors in the selection of the type of surgical procedure. 相似文献
88.
89.
Francesc Carreras Josep Freixas María Albina Puente 《Reliability Engineering & System Safety》2004,83(3):323-332
The index introduced here provides a normalized measure of the effectiveness of any semicoherent structure. We study the mathematical properties of the index and derive different axiomatic characterizations for it. Moreover, close relationships are shown to reliability functions and also to the Birnbaum structural importance measure—for which twice the performance index plays the role of potential function—that give rise to computational procedures. Some numerical examples illustrate the application of the index. 相似文献
90.
JA Molina F de Bustos FJ Jiménez-Jiménez J Benito-León M Ortí-Pareja T Gasalla A Tallón-Barranco JA Navarro J Arenas R Enríquez-de-Salamanca 《Canadian Metallurgical Quarterly》1997,104(11-12):1287-1293
We compared CSF and serum levels, and the CSF/serum ratio of alpha-tocopherol (vitamin E), measured by HPLC, in 34 patients with Parkinson's disease (PD) and 47 controls. CSF and serum vitamin E levels were correlate. The mean CSF and serum vitamin E levels, and the CSF/serum ratio of PD patients did not differ significantly between the groups. There was no influence of antiparkinsonian therapy on CSF vitamin E levels. CSF vitamin E levels did not correlate with age, age at onset, duration of the disease, scores of the Unified Parkinson Disease Rating Scale of the Hoehn and Yahr staging in the PD group. These results suggest that CSF vitamin E concentrations are unrelated with the risk for PD. 相似文献