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61.
The aim of this study is to provide preliminary observations on the microanatomy of Rhincodon typus skin using histology and electron microscopy analyses. Skin biopsies were obtained from a deceased juvenile male shark (548 cm total length) stranded in La Paz, Mexico, during February 2018. The results of this study evidenced the basic structure of the dermal denticles in the epidermis of the trunk of the shark, as well as the composition of the connective tissue in the hypodermis. Histological images of the hypodermis showed a high concentration of collagen fibres, formed by a large number of fine and wavy fibres of compact shape and little intercellular substance.  相似文献   
62.
Biological Invasions - It is widely assumed that spillover of alien parasites to native host species severely impacts naïve populations, ultimately conferring a competitive advantage to...  相似文献   
63.
Locally advanced rectal cancer requires a multidisciplinary management, traditionally based on neo-adjuvant (chemo) radiotherapy, conservative surgery with total mesorectal excision and adjuvant chemotherapy. Despite effective in term of local control, this strategy is linked to a high risk of distant metastasis (up to 30%). In this context, recent published randomized phase III clinical trials have tested the potential benefits with a different sequencing and/or intensification of the standard components of the trimodal therapy.Here, we briefly assess the efficacy and discuss the clinical relevance of total neoadjuvant treatment with a focus on indications and results in the short-course radiotherapy followed by chemotherapy use for this setting of patients. Long term results and additional prospective studies are necessary to more accurately estimate the clinical benefit and further establish the role of total neoadjuvant therapy in locally advanced rectal cancer disease.  相似文献   
64.
In the highly active antiretroviral therapy (HAART) era, hepatocellular carcinoma (HCC) is arising as a common late complication of human immunodeficiency virus (HIV) infection, with a great impact on morbidity and mortality. Though HIV infection alone may not be sufficient to promote hepatocarcinogenesis, the complex interaction of HIV with hepatitis is a main aspect influencing HCC morbidity and mortality.Data about sorafenib effectiveness and safety in HIV-infected patients are limited, particularly for patients who are on HAART. However, in properly selected subgroups, outcomes may be comparable to those of HIV-uninfected patients. Scarce data are available for those other systemic treatments, either tyrosine kinase inhibitors, as well as immune checkpoint inhibitors (ICIs), which have been added to our therapeutic armamentarium. This review examines the influence of HIV infection on HCC development and natural history, summarizes main data on systemic therapies, offers some insight into possible mechanisms of T cell exhaustion and reversal of HIV latency with ICIs and issues about clinical trials enrollment. Nowadays, routine exclusion of HIV-infected patients from clinical trial participation is totally inappropriate, since it leaves a number of patients deprived of life-prolonging therapies.  相似文献   
65.
To test whether the influence of manual activity should be considered when interpreting the results of nerve conduction study (NCS) of the upper limbs performed during work shifts, we evaluated the short-term effect of 90-min repetitive manual work on NCS parameters. Twenty-eight healthy volunteers underwent NCS of the dominant limb at the end of an interview (T0), after a 30-min rest in sitting position (T1) and after performing a standardized 90-min manual task (T2). The task was designed to simulate typical assembly and packing activities. No significant differences were observed for skin temperature (Ts) and NCS parameters between T0 and T1. Significantly (p < 0.001) higher Ts mean values were found at T2 as compared to the previous tests for both females and males. The regression analysis showed an association between temperature variation and nerve conduction velocity values for the median and ulnar nerve at T2 as compared to T1. In females, a reduction of the mean sensory nerve action potential (SNAP) amplitude at T2 was recorded, whereas an opposite trend was observed among males. Manual work is able to influence hand Ts and to modify NCS parameters. SNAP amplitudes changes suggest gender differences in peripheral nerve characteristics that deserve further investigation.  相似文献   
66.
The GPR120 gene (also known as FFAR4 or O3FAR1) encodes for a functional omega-3 fatty acid receptor/sensor that mediates potent insulin sensitizing effects by repressing macrophage-induced tissue inflammation. For its functional role, GPR120 could be considered a potential target gene in animal nutrigenetics. In this work we resequenced the porcine GPR120 gene by high throughput Ion Torrent semiconductor sequencing of amplified fragments obtained from 8 DNA pools derived, on the whole, from 153 pigs of different breeds/populations (two Italian Large White pools, Italian Duroc, Italian Landrace, Casertana, Pietrain, Meishan, and wild boars). Three single nucleotide polymorphisms (SNPs), two synonymous substitutions and one in the putative 3′-untranslated region (g.114765469C > T), were identified and their allele frequencies were estimated by sequencing reads count. The g.114765469C > T SNP was also genotyped by PCR-RFLP confirming estimated frequency in Italian Large White pools. Then, this SNP was analyzed in two Italian Large White cohorts using a selective genotyping approach based on extreme and divergent pigs for back fat thickness (BFT) estimated breeding value (EBV) and average daily gain (ADG) EBV. Significant differences of allele and genotype frequencies distribution was observed between the extreme ADG-EBV groups (P < 0.001) whereas this marker was not associated with BFT-EBV.  相似文献   
67.
Based on general morphology, spore measurements and ornamentation (scanning electron microscope), genome size estimation, and molecular systematics (trnL-trnF IGS), we show the extreme systematic complexity within the European representatives of the genus Ophioglossum. In particular, three hybrids from Tuscany are described: the tetraploid O. × pierinii Peruzzi, Magrini, Marchetti & Viane, seen as the hybrid between diploid O. lusitanicum L. and hexaploid O. azoricum C.Presl; the tetraploid O. × giovanninii Peruzzi, Pierini, Magrini, Marchetti & Viane, seen as the homoploid hybrid between tetraploid O. vulgatum L. and tetraploid O. × pierinii Peruzzi, Magrini, Marchetti & Viane; the pentaploid O. × pseudoazoricum Peruzzi, Pierini, Magrini, Marchetti & Viane, seen as the hybrid between hexaploid O. azoricum C.Presl and tetraploid O. vulgatum L. All the three new taxa grow in different localities in the Monte Pisano mountain range.  相似文献   
68.
69.
Abstract

The first unambiguous documentation of hybridism in the genus Doronicum (Senecioneae – Asteraceae) is reported. All our morphological, karyological and molecular data concur to indicate that Doronicum × minutilloi Peruzzi hybr. nov. (2n = 60) is a hybrid growing in Monti Aurunci (Central Italy), originated from the spontaneous crossing D. orientale Hoffm. (2n = 60) × D. columnae Ten. (2n = 60). This new hybrid shows a slightly higher morphological, karyotypic and ribotypic affinity with D. columnae, but shares a trnL-trnF IGS haplotype with D. orientale, and co-occurs with the latter species only; it has reduced fertility and a high potential for vegetative propagation through rhizome fragmentation. Our results led us to suspect in fieri homoploid hybrid speciation.  相似文献   
70.
Campylobacter have emerged as the most common bacterial food-borne illness in the developed world. The ability to reduce Campylobacter infections in humans is linked to the full comprehension of the principal key aspects of its infection cycle. A microbial diagnostic microarray detecting Campylobacter housekeeping, structural, and virulence associated genes was designed and validated using genomic DNA from reference and field strains of Campylobacter jejuni and coli isolated from human, chicken, and raw milk. This microarray was confirmed to be a powerful diagnostic tool for monitoring emerging Campylobacter pathotypes as well as for epidemiological, environmental, and phylogenetic studies including the evaluation of genome plasticity.  相似文献   
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