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1.
Adv Sci (Weinh) ; 11(26): e2400349, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38713747

RESUMEN

Critical-size bone defects pose a formidable challenge in clinical treatment, prompting extensive research efforts to address this problem. In this study, an inorganic-organic multifunctional composite hydrogel denoted as PLG-g-TA/VEGF/Sr-BGNPs is developed, engineered for the synergistic management of bone defects. The composite hydrogel demonstrated the capacity for mineralization, hydroxyapatite formation, and gradual release of essential functional ions and vascular endothelial growth factor (VEGF) and also maintained an alkaline microenvironment. The composite hydrogel promoted the proliferation and osteogenic differentiation of rat bone marrow mesenchymal stem cells (rBMSCs), as indicated by increased expression of osteogenesis-related genes and proteins in vitro. Moreover, the composite hydrogel significantly enhanced the tube-forming capability of human umbilical vein endothelial cells (HUVECs) and effectively inhibited the process of osteoblastic differentiation of nuclear factor kappa-B ligand (RANKL)-induced Raw264.7 cells and osteoclast bone resorption. After the implantation of the composite hydrogel into rat cranial bone defects, the expression of osteogenic and angiogenic biomarkers increased, substantiating its efficacy in promoting bone defect repair in vivo. The commendable attributes of the multifunctional composite hydrogel underscore its pivotal role in expediting hydrogel-associated bone growth and repairing critical bone defects, positioning it as a promising adjuvant therapy candidate for large-segment bone defects.


Asunto(s)
Regeneración Ósea , Hidrogeles , Osteogénesis , Factor A de Crecimiento Endotelial Vascular , Animales , Ratas , Regeneración Ósea/efectos de los fármacos , Hidrogeles/química , Hidrogeles/farmacología , Factor A de Crecimiento Endotelial Vascular/metabolismo , Osteogénesis/efectos de los fármacos , Humanos , Diferenciación Celular/efectos de los fármacos , Células Madre Mesenquimatosas/efectos de los fármacos , Células Madre Mesenquimatosas/metabolismo , Ratones , Células Endoteliales de la Vena Umbilical Humana , Ratas Sprague-Dawley , Vidrio/química , Modelos Animales de Enfermedad , Silicatos/química , Silicatos/farmacología , Proliferación Celular/efectos de los fármacos , Masculino
2.
Int J Food Microbiol ; 414: 110620, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38382414

RESUMEN

In China and Southeast Asia, pre-fermented coconut water is commonly used for the production of nata de coco, a jelly-like fermented food that consists of bacterial cellulose (BC). The inherent natural fermentation process of coconut water introduces uncontrollable variables, which can lead to unstable yields during BC production. This study involved the collection of spontaneously pre-fermented coconut water over a five-month production cycle. The aim was to evaluate the microbiota and metabolite profile, as well as determine its impact on BC synthesis by Komagataeibacter nataicola. Significant variations in the microbial community structure and metabolite profile of pre-fermented coconut water were observed across different production months, these variations had significant effects on BC synthesis by K. nataicola. A total of 52 different bacterial genera and 32 different fungal genera were identified as potential biotic factors that can influence BC production. Additionally, several abiotic factors, including lactate (VIP = 4.92), mannitol (VIP = 4.22), ethanol (VIP = 2.67), and ascorbate (VIP = 1.61), were found to be potential driving forces affecting BC synthesis by K. nataicola. Upon further analysis, the correlation network indicated that 14 biotic factors had a significant contribution to BC production in three strains of K. nataicola. These factors included 8 bacterial genera, such as Limosilactobacillus and Lactiplantibacillus, and 6 fungal genera, such as Meyerozyma and Ogataea. The abiotic factors lactate, mannitol, and ethanol showed a positive correlation with the BC yield. This study provides significant insights into controlling the fermentation processes of pre-fermented coconut water in industrial settings.


Asunto(s)
Acetobacteraceae , Celulosa , Cocos , Fermentación , Celulosa/química , Etanol , Lactatos , Manitol
3.
Curr Atheroscler Rep ; 25(10): 751-768, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37768409

RESUMEN

PURPOSE OF REVIEW: Acute coronary syndrome (ACS) and non-alcoholic fatty liver disease (NAFLD) are two clinically common disease entities that share numerous risk factors. This review aimed to discuss the impacts of NAFLD on ACS. RECENT FINDINGS: In an era of improved control of traditional risk factors, the substantial burden of cardiometabolic abnormalities has caused widespread concern. NAFLD is considered the hepatic component of metabolic syndrome, which can exert an impact on human health beyond the liver. Accumulating studies have demonstrated that NAFLD is closely related to cardiovascular disease, especially coronary artery disease. Interestingly, although recent data have suggested an association between NAFLD and the incidence and outcomes of ACS, the results are not consistent. In this review, we comprehensively summarized evidence and controversies regarding whether NAFLD is a contributor to either the development of ACS or worse outcomes in patients with ACS. The potential pathophysiological and molecular mechanisms involved in the impacts of NAFLD on ACS were also elucidated.


Asunto(s)
Síndrome Coronario Agudo , Síndrome Metabólico , Enfermedad del Hígado Graso no Alcohólico , Humanos , Enfermedad del Hígado Graso no Alcohólico/complicaciones , Enfermedad del Hígado Graso no Alcohólico/epidemiología , Síndrome Coronario Agudo/epidemiología , Factores de Riesgo
4.
Clin Chim Acta ; 547: 117444, 2023 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-37315725

RESUMEN

Diabetes mellitus (DM) is strongly associated with an increased risk of atherosclerotic cardiovascular disease (ASCVD). Proprotein convertase subtilisin/kexin type 9 (PCSK9) was recently identified as an important regulator of circulating low-density lipoprotein-cholesterol (LDL-C) levels via degradation of the LDL receptor, proving to be a valid target to improve lipoprotein profiles and cardiovascular outcomes in patients with ASCVD. Beyond LDL receptor processing and cholesterol homeostasis, the PCSK9 protein has recently been verified to be associated with glucose metabolism. Importantly, clinical trials suggest that treatment with PCSK9 inhibitors for patients with DM is more effective. Hence, in this review, we summarize the current findings derived from experimental, preclinical, and clinical studies regarding the association between PCSK9 and glucose metabolism, including the relationship of PCSK9 genetic mutations to glucose metabolism and diabetes, the link between plasma PCSK9 concentrations and glucose metabolic parameters, the effects of glucose-lowering drugs on plasma PCSK9 levels and the impacts of PCSK9 inhibitors on cardiovascular outcomes of patients with DM. Clinically, exploring this field may improve our understanding regarding the roles of PCSK9 in glucose metabolism and may offer an in-depth interpretation of how PCSK9 inhibitors exert effects on the treatment of patients with DM.


Asunto(s)
Aterosclerosis , Proproteína Convertasa 9 , Humanos , Inhibidores de PCSK9 , LDL-Colesterol , Receptores de LDL/metabolismo , Glucosa/metabolismo
5.
Macromol Rapid Commun ; 44(1): e2100916, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35080287

RESUMEN

Size regulation of polydopamine nanoparticles (PDA NPs) is vital to melanin-inspired materials. The general strategy usually focuses on tuning of the reaction parameters which could affect the dopamine (DA) monomer polymerization process, such as pH, temperature, monomer concentration, etc. The reaction between boronic acids and catechols to form boronic esters has been widely applied in many fields, but little attention has been paid in the size regulation of PDA NPs. Here, it is speculated that the fine size regulation of PDA NPs can be directly achieved by using boronic acids and Lewis base molecules. It is found that these issues could indeed significantly affect the stability of the boronic esters formed by boronic acids and DA, which may further inhibit the monomer polymerization kinetics and tune the particle size of the resulting PDA NPs. It is also found that the several intrinsic properties of PDA NPs such as the free radical scavenging ability, UV spectral absorption, photothermal behavior, and structural color all change with the particle size. It is believed that this work can provide new opportunities for fabricating melanin-inspired PDA NPs with well controlled size and properties.


Asunto(s)
Bases de Lewis , Nanopartículas , Ácidos Borónicos , Indoles/química , Nanopartículas/química
6.
Rev Cardiovasc Med ; 24(4): 119, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-39076272

RESUMEN

Atrial fibrillation (AF) is one of the most common cardiac arrhythmias, but its pathogenesis is still poorly understood. Catheter ablation is one of the most effective treatments for AF, but recurrence after ablation remains a challenge. There has been much research into the association of AF recurrence with several factors, including genetics. Over the past decade or so, significant advances have been made in the genetic architecture of atrial fibrillation. Genome-wide association studies (GWAS) have identified over 100 loci for genetic variants associated with atrial fibrillation. However, there is relatively little information on the systematic assessment of the genes related to AF recurrence after ablation. In this review article, we highlight the value of genetic polymorphisms in atrial fibrillation recurrence after catheter ablation and their potential mechanisms in the recurrence process to enhance our understanding of atrial fibrillation recurrence and contribute to individualized treatment strategies for patients with AF.

7.
Plant Divers ; 44(6): 552-564, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36540706

RESUMEN

Engelhardia, a genus of Juglandaceae (the walnut family), is endemic to tropical and subtropical Asia. The rich Cenozoic fossil records and distinctive morphological characters of the living plants have been used to explore the evolutionary history and geographic distribution of Juglandaceae. However, the taxonomy of this genus has been suffered from a lack of in-depth investigation and good specimens across its distribution ranges. Species delimitation of Engelhardia was defined with seven species in 2020, but detailed information on the circumscription of the species still remains poorly understood. In this study, two new species are described from Sulawesi and Borneo, Engelhardia anminiana and E. borneensis. We also revised and reconstructed the phylogeny within Engelhardia using morphological, molecular (plastid and ribosomal), and distribution data. We sampled 787 individuals in 80 populations, and all the samples were genotyped using plastid regions, trnS-trnG, rps16, trnL-trnF, psbA-trnH, and rpl32-trnL; one ribosomal region, nuclear ribosomal internal transcribed spacer (nrITS). The all datasets were used to reconstruct the phylogenetic relationships. Then, the molecular analyses were combined for 738 sheets of specimens with 15 morphological characteristics to further explore the morphological clusters of Engelhardia. Cluster analysis using morphological data confirmed the delimitation of nine Engelhardia species. Also, phylogenetic analysis based on molecular data (i.e., plastid and ribosomal) supported the monophyly of Engelhardia and generated phylogenetic trees that included E. fenzelii, E. roxburghiana, E. borneensis, E. hainanensis, E. anminiana, E. serrata, E. villosa, E. apoensis and the varieties of E. spicata (i.e., E. spicata var. spicata, E. spicata var. rigida, E. spicata var. aceriflora, and E. spicata var. colebrookeana). Our comprehensive taxonomic revision of Engelhardia will provide an insight into understanding the plant diversity in tropical and subtropical Asia.

8.
Opt Express ; 30(20): 35444-35456, 2022 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-36258495

RESUMEN

High-order harmonic generation (HHG) from the interaction of ultra-intense laser pulses with atoms is an important tabletop short-wave coherent light source. Accurate quantum simulations of it present large computational difficulties due to multi-electron multidimensional effects. In this paper, the time-dependent response of hydrogen atoms is calculated using a time-series prediction scheme, the HHG spectrum is reconstructed very accurately. The accuracy of the forecasting is further improved by using a neural network scheme. This scheme is also applied to the simulation of the harmonic emission on multi-electron systems, and the applicability of the scheme is confirmed by the harmonic calculation of complex systems. This method is expected to simulate the nonlinear dynamic process of multi-electron atoms and molecules irradiated by intense laser pulses quickly and accurately.

9.
Medicine (Baltimore) ; 101(41): e31053, 2022 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-36253976

RESUMEN

Left-ventricular thrombus (LVT) is a potentially life-threatening disease. However, few studies have explored the risk factors of in-hospital systemic thromboembolism (ST) in LVT patients. In this multicenter retrospective study, we enrolled myocardial infarction patients with LVT from January 2008 to September 2021. Multivariable logistic regression analysis was applied to identify the independent risk factors for ST in LVT patients. A total number of 160 hospitalized LVT patients [median follow-up period 50 months (18.3-82.5 months)] were subjected to analysis. Of them, 54 (33.8%) patients developed acute myocardial infarction, 16 (10%) had ST, and 33 (20.6%) died. Comparable baseline characteristics were established between the ST and non-ST groups, except for the heart failure classification (P = .014). We obtained the following results from our multivariable analysis, based on the use of HFrEF as a reference: HFpEF [odd ratio (OR), 6.2; 95% confidence interval (CI), 1.4-26.3; P = .014] and HFmrEF (OR, 5.0; 95%CI, 1.1-22.2; P = .033). In conclusion, HFpEF, and HFmrEF may be independent risk factors for in-hospital ST development.


Asunto(s)
Insuficiencia Cardíaca , Infarto del Miocardio , Tromboembolia , Trombosis , Insuficiencia Cardíaca/complicaciones , Insuficiencia Cardíaca/epidemiología , Hospitales , Humanos , Infarto del Miocardio/complicaciones , Infarto del Miocardio/epidemiología , Estudios Retrospectivos , Factores de Riesgo , Volumen Sistólico , Tromboembolia/complicaciones , Tromboembolia/etiología , Trombosis/etiología
10.
Waste Manag ; 153: 167-177, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36099727

RESUMEN

Flotation is an attractive method for separating the different components of waste printed circuit boards (WPCBs) due to its cleanliness and efficiency. Non-metallic particles (NMPs) with good floatability usually need to be floated, however, it is difficult to achieve complete removal. The effect of particle size on the flotation behavior of NMPs, which is usually ignored in previous studies, is concerned in this paper. Flotation tests and kinetic analysis were carried out to reveal the effect of reagent dosage on flotation characteristics of particles in narrow size fractions. As the fineness decreases, the particles are more likely to be floated. Equally, the finer the particle size, the lower the reagent dosage required to achieve the maximum recovery. For 1-0.5 mm and -0.045 mm, the maximum recovery increased from 42.16% (1500 g/t MIBC) to 97.31% (100 g/t MIBC). Therefore, the feasibility of reducing particle size by grinding to improve floatability was verified. The results show that the reduction of particle size can significantly promote its efficiency of being floated. After grinding treatment, -0.045 mm yields in each size fraction (1-0.5, 0.5-0.25, 0.25-0.125, 0.125-0.074, 0.074-0.045 mm) increased by 22.10%, 28.42%, 30.90%, 64.56%, 89.32%, resulting in an increase of 37.71%, 13.12%, 2.82%, 7.82% and 2.00% in maximum recovery, respectively. It is also proved that the particle size, rather than the resin content, has a more significant effect on the floatability of NMPs.


Asunto(s)
Residuos Electrónicos , Residuos Electrónicos/análisis , Cinética , Metales , Tamaño de la Partícula , Reciclaje
11.
J Gastrointest Oncol ; 13(2): 792-801, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35557582

RESUMEN

Background: Early recurrence (ER) after radical resection of hepatocellular carcinoma (HCC) affects the prognosis of patients. Gadolinium ethoxybenzyl-diethylenetriaminepentaacetic acid (Gd-EOB-DTPA)-enhanced magnetic resonance imaging (MRI) can improve the detection rate of small HCC. This study innovatively introduces a new quantitative index combined with qualitative index to compare the differences in clinical and imaging characteristics between ER and non-ER groups and evaluate the feasibility of Gd-EOB-DTPA-enhanced MRI in predicting ER. Methods: A total of 68 patients with HCC confirmed by operation and pathology in the Shandong Cancer Hospital and Institute were included retrospectively. All participants were examined by Gd-EOB-DTPA-enhanced MRI within 3 weeks before surgery. Regular follow-up was performed every 2 months within 1 year after operation. Among them, 18 cases with new lesions were in ER group, and 50 cases without new lesions were in non-ER group. The clinical and imaging data of the 2 groups were collected, and the differences of clinical data and preoperative MRI signs between the ER group and non-ER group were compared. The predictive factors of ER after HCC were analyzed by multivariate logistic regression. Results: The quantitative parameter lesion-to-liver contrast enhancement ratio (LLCER) can predict the pathological grade of HCC (P=0.023). The results of univariate analysis between the ER group and non-ER group showed that there were significant differences in pathological grade (P=0.008), lesion morphology (P=0.011), peritumoral low signal intensity in hepatobiliary phase (HBP) (P<0.001), satellite nodules (P<0.001), and LLCER (P<0.001) between the 2 groups. Multivariate logistic regression analysis showed that HBP peritumoral low signal intensity [odds ratio (OR) =7.214, 95% confidence interval (CI): 1.230-42.312, P=0.029], satellite nodules (OR =9.198, 95% CI: 1.402-60.339, P=0.021), and parameter LLCER value (OR =0.906, 95% CI: 0.826-0.995, P=0.039) were independent predictors of ER of HCC after resection. Conclusions: Preoperative Gd-EOB-DTPA enhanced MRI has important predictive value for early recurrence after radical resection of hepatocellular carcinoma.

12.
Mol Phylogenet Evol ; 171: 107458, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35351637

RESUMEN

The complexity of global biodiversity in the tropical Indochina Peninsula and subtropical China bioregions has fascinated biologists for decades, but little is known about the spatiotemporal patterns in these regions. Accordingly, the aims of present study were to investigate the evolutionary and distribution patterns of Engelhardia in these regions and establish a model for examining biogeographic patterns and geological events throughout the tropical Indochina Peninsula and subtropical China. The effects of geological events occurring in the area between the Indochina Peninsula and subtropical China bioregions on the two trees species (i.e., E. roxburghiana and E. fenzelii) were evaluated. A robust phylogenetic framework of 884 individuals from 79 populations was used to generate time-calibrated cytoplasmic and nuclear phylogenetic frameworks based on cpDNA, nrDNA, and nSSR data, respectively. When considered along with ancestral area reconstructions, the genetic data were also used to assess and reconstruct the species' population genetic structure and diversity. These analyses yielded important information about the (1) historical distribution relationships between the tropical and subtropical flora of China; (2) effects of the East Asian summer monsoon (EASM) on the evolutionary history of Asia's plants; and (3) importance of biogeography in conservation planning. Although cytoplasmic-nuclear discordance indicated cpDNA and nrDNA were subject to distinct evolutionary mechanisms that reflected respective evolutionary histories of the plastid and nuclear genomes of prior demographic and biogeographic events. The tropical elements of Engelhardia occupied the Indochina Peninsula during the early Eocene, whereas the subtropical elements were transformed from the tropical elements during Miocene cooling and the onset of the EASM at the Oligocene-Miocene boundary, intensified during the late Miocene and Pliocene, facilitating the transformation of Engelhardia from the tropical Indochina Peninsula to subtropical China. Demographic history provided insights into prominent planning frameworks in conservation biology, namely that subtropical China functioned as a refugium during past climate oscillations and will continue to serve in this capacity in the future.


Asunto(s)
Biodiversidad , Plantas , China , ADN de Cloroplastos , Humanos , Indochina , Filogenia , Filogeografía
13.
ACS Biomater Sci Eng ; 8(2): 626-637, 2022 02 14.
Artículo en Inglés | MEDLINE | ID: mdl-35090109

RESUMEN

Polypeptide-based injectable hydrogels have attracted the attention of biomedical researchers due to their unique biocompatibility and biodegradability, tunable residue chirality, and secondary conformation of polypeptide chains. In the present study, four types of poly(ethylene glycol)-block-poly(glutamic acid)s with different topological structures and residue chirality of polypeptide segments were developed, which were grafted with tyramine side groups for further cross-linking. The results demonstrated that the covalent conjugation between the tyramine groups in the presence of horseradish peroxidase and hydrogen peroxide could form porous hydrogels rapidly. Additionally, the gelation time and mechanical strength of the hydrogels were measured. All the polymer precursors and hydrogels exhibited good cytocompatibility in vitro. Further assessment of the enzymatic degradability of the hydrogels and copolymers in vitro revealed that the degradation rate was influenced by the adjustment of polymer topology or residue chirality of polypeptide copolymers. Subsequently, the effect of copolymer topology and polypeptide chirality on in vivo biodegradability and biocompatibility was assessed. This study will provide insights into the relationship between copolymer structures and hydrogel properties and benefit future polypeptide-based hydrogel studies in biomedical applications.


Asunto(s)
Hidrogeles , Polímeros , Materiales Biocompatibles , Hidrogeles/química , Péptidos/química , Polietilenglicoles/química
15.
Mol Phylogenet Evol ; 152: 106918, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32738292

RESUMEN

Enhanced efficacy in species delimitation is critically important in biology given the pending biodiversity crisis under global warming and anthropogenic activity. In particular, delineation of traditional classifications in view of the complexity of species requires an integrative approach to effectively define species boundaries, and this is a major focus of systematic biology. Here, we explored species delimitation of Engelhardia in tropical and subtropical Asia. In total, 716 individuals in 71 populations were genotyped using five chloroplast regions, one nuclear DNA region (nrITS), and 11 nuclear simple sequence repeats (nSSR). Phylogenetic trees were constructed and relationships among species were assessed. Molecular analyses were then combined with 14 morphological characteristics of 720 specimens to further explore the species boundaries of Engelhardia. Integrating phylogenetic and morphological clusters provided well-resolved relationships to delineate seven species. The results suggested that: first, that E. fenzelii, E. roxburghiana, E. hainanensis, E. apoensis, and E. serrata are distinct species; second, E. spicata var. spicata, E. spicata var. aceriflora, E. spicata var. colebrookeana, and E. rigida should be combined under E. spicata and treated as a species complex; third, E. serrata var. cambodica should be raised to species level and named E. villosa. We illuminated that bias thresholds determining the cluster number for delimiting species boundaries were substantially reduced when morphological data were incorporated. Our results urge caution when using the concepts of subspecies and varieties in order to prevent confusion, particularly with respect to species delimitation for tropical and subtropical species. In some cases, re-ranking or combining subspecies and/or varieties may enable more accurate species delimitation.


Asunto(s)
Juglandaceae/clasificación , Filogenia , Animales , Asia , Biodiversidad , Núcleo Celular/genética , Cloroplastos/genética , ADN de Plantas/genética , Juglandaceae/anatomía & histología , Juglandaceae/genética , Repeticiones de Microsatélite , Especificidad de la Especie
16.
PhytoKeys ; 138: 41-47, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31988604

RESUMEN

Colocasia kachinensis S.S. Zhou & J.T. Yin, is described and illustrated as a new species of Araceae from Kachin, Mynamar. The morphological characters are compared to those of other Colocasia species. Colocasia kachinensis is closely related to C. menglaensis J.T Yin, H. Li & Z.F. Xu, 2004, but differs from in having an erect stem, no stolons, smaller size, a different pattern of surface bristle distribution and male flowers 1-4-androus with stamens connate in truncate synandrium.

17.
PhytoKeys ; 138: 113-123, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31988606

RESUMEN

Myanmar is known for its high species richness of genus Gastrochilus; however, most of them lack proper information for taxonomic revision. During four years of field investigation in Myanmar, two new distributional records were encountered, namely, G. arunachalensis and G. corymbosus and one species, i.e. G. pechei was rediscovered after its original description. The three species were not easy to interpret from the available original descriptions and types due to severely shrunk or poorly preserved specimens. Therefore, we hereby present more detailed illustrations and updated descriptions for these species, based on freshly collected materials.

18.
PhytoKeys ; 138: 131-137, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31988608

RESUMEN

Zingiber natmataungense S.S.Zhou & R.Li (Zingiberaceae), a new species from Natma Taung National Park, Chin State, Myanmar, is described and illustrated. The new species is morphologically similar to Z. yunnanense, but differs by: leaf blade abaxially light green, glabrous, ligule sparsely pubescent, ca. 2-3 mm, bracts glabrous; calyx white 20-21 × 3.2-3.5 mm, glabrous, apex obviously 3-toothed; corolla tube white, ca. 3.9-4.1 cm, labellum lateral lobes, ca. 1.5-1.7 × 0.6-0.7 cm; stamen with sparse pubescent, filament white, glabrous, 1-2 mm; anther connective appendage yellowish proximally, purplish distally; ovary white, sparsely white pubescent, epigynous glands, ca. 6-7 mm long, tapered, apex whorled, yellow. This new species is also similar to Z. teres, but has a different flower colour.

19.
PhytoKeys ; 138: 219-223, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31988615

RESUMEN

A new species, Ophiorrhiza monsvictoriae S.S.Zhou & L.D.Duan, discovered at Natma Taung (Mt.Victoria) National Park, Chin State, Myanmar, is described and illustrated. The new species is morphologically similar to O. dulongensis, but differs from the latter by its stipules broadly triangular, 2-4 mm long, inflorescence axillary, 1-flowered, bracts lanceolate to subulate, 1-2 mm long, puberulous, calyx pilose, 1-2 mm long, lobes and tube equal length, corolla narrowly funnelform, 15 mm long, puberulous outside.

20.
J Appl Stat ; 47(12): 2178-2191, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-35706834

RESUMEN

Stratified regression models are commonly employed when study subjects may come from possibly different strata such as different medical centers, and for the situation, one common question of interest is to test the existence of the stratum effect. To address this, there exists some literature on the testing of the stratum effects under the framework of the proportional hazards model when one observes right-censored data or interval-censored data. In this paper, we consider the situation under the additive hazards model when one faces current status data, for which there does not seem to exist an established test procedure. The asymptotic distributions of the proposed test procedure are provided. Also a simulation study is performed to evaluate the performance of the proposed method and indicates that it works well for practical situations. The approach is applied to a set of real current status data from a tumorigenicity study.

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