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71.
This research sought to identify the aphid virus vector species associated with lettuce and broccoli crops in Spain, and to determine their population dynamics and ability to transmit Lettuce mosaic virus (LMV). Green tile traps and Moericke yellow water-pan traps were used to monitor aphid flights during the spring and autumn growing seasons of 2001. Aphid species feeding on lettuce were counted weekly. The transmission efficiencies of LMV were determined for the aphid species caught most frequently. The Moericke traps generally caught more aphid species than the tile trap, but the latter was the most suitable to estimate flight activity of species involved in virus spread. Spring aphid catches indicated that the main aphid species landing on lettuce in the regions of Madrid and Murcia was Hyperomyzus lactucae, but Brachycaudus helichrysi was also abundant in both regions. In broccoli in the Navarra region, the most abundant species in spring were Aphis fabae, B. helichrysi and H. lactucae. In autumn-sown crops, the main species landing on lettuce in the Madrid region were Hyadaphis coriandri and Aphis spiraecola. In Murcia, A. spiraecola and Myzus persicae were the most abundant, while in Navarra, Therioaphis trifolii, and various Aphis spp. were the most numerous landing on broccoli. The main aphid species colonising lettuce was Nasonovia ribisnigri, but other less abundant colonising species were Aulacorthum solani and Macrosiphum euphorbiae. The most efficient vectors of LMV were M. persicae, Aphis gossypii and M. euphorbiae, while A. fabae and H. lactucae transmitted with low efficiency, and Rhopalosiphum padi and N. ribisnigri did not transmit. Occurrence of LMV epidemics in central Spain in relation to aphid flights and the role of weeds as virus reservoirs is discussed.  相似文献   
72.
Injection of the bacterial superantigen Staphylococcus aureus enterotoxin B (SEB) into mice provokes a rapid expansion and subsequent contraction of the pool of SEB-reactive T cells bearing T cell receptor (TcR) Vβ8 gene products. Given that interleukin 2 (IL-2) stimulates proliferation, abolishes anergy, and counteracts apoptotic cell death in T cells in vitro, we tested whether the IL-2 synthesis inhibitor cyclosporin A (CsA) or a vaccinia virus recombinant releasing high amounts of human IL-2 modulate SEB responses in vivo. Surprisingly, neither IL-2 nor CsA were able to change the in vivo kinetics and magnitude of SEB-induced expansion, unresponsiveness to SEB, and peripheral clonal deletion of T cells expressing products of the SEB-reactive TcR Vβ8 gene family. In accord with these in vivo observations, IL-2 is incapable of reversing “anergy” and apoptotic cell death of Vβ8+ SEB-reactive T cells isolated from SEB-primed mice in vitro. Accordingly, upon SEB injection Vβ8+ T cells expand rapidly, without expressing IL-2 receptor (IL-2R)α chains in vivo, although SEB induces IL-2R α in vitro. Altogether, these results indicate that the IL-2/IL-2R-mediated pathway is not involved in T cell repertoire modulation by bacterial superantigens. Moreover, the data suggest that unresponsiveness of Vβ8+ T cells from SEB-primed mice is not a reversible process, but involves an unreversible commitment to programmed cell death. Absence or presence of IL-2 responsiveness could be a hallmark to distinguish truly reversible anergy and peripheral clonal deletion.  相似文献   
73.
Hybridisation of tissue prints with nonradioactive cDNA probes was developed to detect cucumber vein yellowing virus (CVYV) in cucurbit plants. Results showed irregular distribution of the virus within cucumber, zucchini or melon plants without defined tropism for a specific tissue. Therefore, reliable diagnosis of CVYV requires analysis of tissue prints from at least five different plant sites. This detection procedure allows rapid analysis of large numbers of plants and it can be useful for epidemiological studies of CVYV and to control virus spread via eradication of early foci.  相似文献   
74.
Murine antisera specific for the α (1→3) and α (1→6)-linked glucosyl determinants of dextran, as well as for meningococcal polysaccharide group C, have been examined for the distribution of their immunoglobulin classes and subclasses. Whereas the thymus-independent anti-α (1→3) dextran response in BALB/c mice was found to be IgM > IgG3 > IgA, thus corresponding to previously published work, neither the α (1→6) response in its thymus-dependent or-independent form, nor the response to purified meningococcal polysaccharide, corresponded to this pattern. No preference for any of the IgG subclasses appeared for these antigens when given as thymus-independent carbohydrates. On the other hand, thymus-dependent forms of α (1→6) dextran showed an IgG1 > IgG3 > IgG2 pattern.  相似文献   
75.
Positive influences of family members have been associated with a high probability of children’s daily breakfast consumption. Therefore, the aim of this study was to scrutinize the association of breakfast routines between mothers and their children. The baseline data of the Feel4Diabetes-study was obtained in 9760 children (49.05% boys)–mother pairs in six European countries. A parental self-reported questionnaire gauging the frequency of breakfast consumption and of breakfast´ foods and beverages consumption was used. Agreement in routines of mothers and their children’s breakfast consumption was analyzed in sex-specific crosstabs. The relationship of breakfast routine and food groups’ consumption between mothers and their children was assessed with analysis of covariance. The highest proportion of children who always consumed breakfast were those whose mothers always consumed it. Children consuming breakfast regularly had a higher intake of milk or unsweetened dairy products and all kind of cereal products (low fiber and whole-grain) than occasional breakfast consumers (p < 0.05). The strong similarity between mothers and children suggests a transfer of breakfast routine from mothers to their children, as a high proportion of children who usually consume breakfast were from mothers also consuming breakfast. All breakfast foods and beverages consumption frequencies were similar between children and their mothers.  相似文献   
76.
目的:应用微乳液反应法制备磺胺嘧啶银均匀微晶,均匀制得的微晶的粒径大小约为2~4um,均匀微晶的结晶性好,纯度高。用均匀设计方法优化条件,制备的均匀的微晶平均粒径大小为2.09um,实验结果达到预测结果要求。结论:用微乳液反应法能获得磺胺嘧啶银均匀微晶。  相似文献   
77.
The objective of our research is to develop computer-based tools to automate the clinical evaluation of the electroencephalogram (EEG) and visual evoked potentials (VEP). This paper describes a set of solutions to support all the aspects regarding the standard procedures of the diagnosis in neurophysiology, including: (1) acquisition and real-time processing and compression of EEG and VEP signals, (2) real-time brain mapping of spectral powers, (3) classifier design, (4) automatic detection of morphologies through supervised neural networks. (5) signal analysis through fuzzy modelling, and (6) a knowledge based approach to classifier design.  相似文献   
78.
ObjectiveWe analyzed the profile of patients who were candidates for neoadjuvant chemotherapy (NACT) in stage pT2-4aN0M0, the tolerability and adherence of our cisplatin-based protocol and oncological outcomes.Material and methodsRetrospective observational cohort study including patients diagnosed with muscle-invasive bladder carcinoma treated with NACT. Clinical, histopathological, therapeutic and evolutionary characteristics of the patients were analyzed. The use of NACT was evaluated by the complete response in the surgical specimen (pT0). This and other pathological factors were related to overall survival and progression-free survival.ResultsWe included 90 patients with muscle-invasive bladder carcinoma (clinical stage T2a-T4aN0M0) who received a cisplatin-based NACT regimen between January 2011 and December 2018, prior to radical surgery. Forty percent of patients presented an adverse reaction, with a compliance with the NACT regimen of 92.2%. There were no deaths related to systemic treatment and no adverse reaction to treatment made radical cystectomy impracticable. After performing radical cystectomy, the presence of complete response (pT0) was observed in 20 patients (21%), lower stage in the surgical specimen (<pT2) in 36 patients (40%), positive surgical margins in 7 patients (8%), lymph node involvement (N1) in 16 patients (17.8%). A shorter time to progression was observed in the group of patients who did not achieve a complete pathological response (53 months vs. 83.1 in pT0 patients, P = 0.012), in patients with lymph node involvement compared to pN0 (65.4 vs. 28, 2 months, P = 0.014) and in those with positive surgical margins compared to those with tumor-free margins (63.5 vs. 8.5 months, P = 0.021).ConclusionThe adequate selection of patients with muscle-invasive bladder carcinoma has shown a good tolerance to NACT, with a high compliance rate prior to RC. The improvement in the complete response rate implies a greater survival in this group of patients, with lymph node involvement and positive surgical margins being important prognostic factors.  相似文献   
79.
Thyroidectomy is the most frequent procedure in endocrine surgery. The conventional approach through a collar incision, as described by Kocher in XIXth century, has become the “gold standard”. It is continuously evolving in spite of, many years ago, it showed to be safe and efficient with quality standards difficult to beat.Endoscopic and robotic surgery have developed “new approaches” to thyroid in order to improve the cosmetic results, looking even for invisible scars.We have done a thoughtful review of most of them trying to understand their benefits and drawbacks.Currently none of these “new approaches” have been shown to be better than conventional open thyroidectomy beyond offering a better cosmetic result. Besides, only a small percentage of patients can benefit of them. However, most of these approaches will remain if they treat the diseased thyroid and also improve the quality of life of our patients.  相似文献   
80.
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