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871.
This paper reports the discovery of an unusual population of Syagrus cocoides Martius located in the municipality of Barra do Corda, state of Maranhão, northeastern Brazil. The most interesting characteristic of this population is the high number of individuals with branched stems. Sampling showed that 16.12% of the population consisted of bifurcate adult individuals and 14.17% were bifurcate seedlings. The branching phenomenon in palms is reviewed, anc competing hypotheses are discussed to explain the branching in Syagrus cocoides and its ecological and evolutionary significance. We conclude that the most likely type of branching is by dichotomy. 相似文献
872.
de Souza Marcelo Claro Habermann Gustavo do Amaral Cárita Liberato Rosa Annylory Lima Pinheiro Marcelo Henrique Ongaro Da Costa Fernando Batista 《Plant and Soil》2017,416(1-2):377-389
Plant and Soil - Alterations in root growth and rhizosphere processes in maize (Zea mays L.) occur under phosphorus (P) deficiency, but the dynamics of root morphological and physiological... 相似文献
873.
874.
David C. Jenkins David S. Pearson Andrew Harvey Ian D. Sylvester Michael A. Geeves Teresa J. T. Pinheiro 《European biophysics journal : EBJ》2009,38(5):625-635
The conversion of the cellular form of the prion protein (PrPC) to an altered disease state, generally denoted as scrapie isoform (PrPSc), appears to be a crucial molecular event in prion diseases. The details of this conformational transition are not fully
understood, but it is perceived that they are associated with misfolding of PrP or its incapacity to maintain the native fold
during its cell cycle. Here we present a tryptophan mutant of PrP (F198W), which has enhanced fluorescence sensitivity to
unfolding/refolding transitions. Equilibrium folding was studied by circular dichroism and fluorescence. Pressure-jump experiments
were successfully applied to reveal rapid submillisecond folding events of PrP at temperatures not accessed before.
D. C. Jenkins and D. S. Pearson contributed equally. 相似文献
875.
Miriam R Faria Mara S Hoshida Eloisa AV Ferro Francesca Ietta Luana Paulesu Estela Bevilacqua 《Reproductive biology and endocrinology : RB&E》2010,8(1):95
Background
Macrophage migration inhibitory factor (MIF) has special pro-inflammatory roles, affecting the functions of macrophages and lymphocytes and counter-regulating the effects of glucocorticoids on the immune response. The conspicuous expression of MIF during human implantation and early embryonic development also suggests this factor acts in reproductive functions. The overall goal of this study was to evaluate Mif expression by trophoblast and embryo placental cells during mouse pregnancy. 相似文献876.
Marcelo Antonio Amaro Pinheiro Marcio Camargo Araujo João Maria Helena Arruda Leme Akeme Milena Ferreira Matsunaga Juliana Priscila Piva Rio Patricio Hernáez 《Invertebrate reproduction & development.》2017,61(2):78-89
Petrolisthes armatus (Gibbes, 1850) life history was evaluated based on growth and reproduction. Specimens were captured at Ubatuba (Brazil), identified, sexed and measured: carapace (CL, length; CW, width), larger cheliped propodus (PL, length; PW, width; and PH, height), and 2th and 5th abdominal somite (AW2 and AW5, width). Relative growth was studied using CL as independent variable and its relation with other variables (dependents), to estimate puberty size and morphological maturity. Fecundity was represented by number of eggs vs. body size CL, with a better fit using a power function. Considering the 257 specimens analyzed, males were larger than females, and the overall sex ratio was 1:1, with some differences among size classes. Maturity (puberty size) was revealed by: AW2 × CL (males: 8.6 mm CL; females: 7.6 mm CL); and AW5 × CL (7.1 and 7.6 mm CL, respectively). Reproduction was continuous, but more intense in rainy season and recruitment occurring in dry season. Fecundity of this species was 228 ± 163 eggs, with better fit by a power function (R2 = 0.72). Maturity size and growth differed when a pristine area (Ubatuba) was compared with a polluted area (São Sebastião), in the same Brazilian area (São Paulo State). 相似文献
877.
Icaro dos Santos Dieter Haemmerich Cleber da Silva Pinheiro Adson Ferreira da Rocha 《Biomedical engineering online》2008,7(1):21
Background
One of the current shortcomings of radiofrequency (RF) tumor ablation is its limited performance in regions close to large blood vessels, resulting in high recurrence rates at these locations. Computer models have been used to determine tissue temperatures during tumor ablation procedures. To simulate large vessels, either constant wall temperature or constant convective heat transfer coefficient (h) have been assumed at the vessel surface to simulate convection. However, the actual distribution of the temperature on the vessel wall is non-uniform and time-varying, and this feature makes the convective coefficient variable. 相似文献878.
D L da Mota L L George P P Pinheiro N L Pinheiro 《Gegenbaurs morphologisches Jahrbuch》1989,135(2):367-377
The intestinal of the 3-toed sloth, Bradypus tridactylus, was studied macroscopically, with light microscope and with histochemical methods for mucosubstances. Macroscopically, the inner surface of the duodenum shows longitudinal and circular folds. There is no caecum, nor appendix. The large intestine consists of a short colon and a large rectal pouch, which has a thick wall. The mucosa of the small intestine has long leaf-shaped villi covered with columnar epithelium having a well developed striated border, and the goblet cells are scattered among the columnar cells. An association between neutral and acidic mucosubstances was detected in the goblet cells. The duodenal (Brunner's) glands are confined exclusively in the lamina propria of the duodenum. No Paneth cells were observed in the crypt lining. Argyrophil and argentaffin cells were found in the entire length of the intestine. The large intestine does not possess villi, but many goblet cells were observed in its mucosa. 相似文献
879.
Mahdieh Ahmadi Ahmad Noori Bita Kalvani Neitali Marcelo Antonio Amaro Pinheiro 《Acta zoologica》2023,104(2):176-184
The purpose of this study was to investigate the relative growth and sexual dimorphism in the hermit crab Clibanarius signatus. The evaluation was done with 955 specimens (494 males, 251 females, and 210 intersexes) captured in Persian Gulf (Iran) during January to December 2015. Animals were submitted to measurements related to weight (BW, total wet weight) and body size related to cephalic shield (SW, width; and SL, length) and propodus of both chelipeds (CPL, length; and CPW, width). Males were larger and heavier than females and intersexes. Both males and females showed a negative allometric growth for the SL–BW and SL–SW relationships, but a positive allometric growth to intersex specimens. To SL–CPL relationship, a negative allometric growth was confirmed in males and females independent of the laterality of the CPL, whereas a contrast was verified in intersexes, with a positive allometric growth occurred for both hands. To SL–CPW relationship, a negative allometric growth (b < 1) occurred in females, independent of the laterality of the CPW, while in males, a positive allometric pattern was confirmed. In intersexes, this relationship was positive except for the right CPW which was isometric. Sexual dimorphism was evident in Clibanarius signatus, with males being the largest and females the smallest specimens in the population. 相似文献
880.
Water deficit (WD) in Lupinus albus L. brings about tissue-specific responses that are dependent on stress intensity. Carbohydrate metabolism is very sensitive to changes in plant water status. Six days from withholding water (DAW), sucrose, glucose and fructose levels of the leaf blade had already increased over 5-fold, and the activities of SS and INV(A) had increased c. 1.5-2 times. From 9 DAW on, when stress intensity was more pronounced, these effects were reversed with fructose and glucose concentrations as well as INV(A) activity dropping in parallel. The stem (specifically the stele) responded to the stress intensification with striking increases in the concentration of sugars, N and S, and in the induction of thaumatin-like-protein and an increase in chitinase and peroxidase. At 13 DAW, the plants lost most of the leaves but on rewatering they fully recovered. Thus, the observed changes appear to contribute to a general mechanism of survival under drought, the stem playing a key role in that process. 相似文献