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71.
Bruna Martins Bezerra Antonio da Silva Souto Lewis George Halsey Nicola Schiel 《Journal of Ethology》2008,26(1):175-178
Bradypus variegatus is a member of the Order Pilosa, Family Bradypodidae, and is distributed in many subtropical and tropical countries in South
and Central America. However, studies on this species in the wild are relatively limited and many aspects of its reproductive
behaviour are unknown or unclear. The current report presents new observations of the reproductive behaviour of B. variegatus in its natural environment. These include details of both a male–female copulation and the simultaneous nurturing of two young
sloths. 相似文献
72.
Summary
Erythroxylum longisetulosum I. Loiola & M. F. Sales and E. timothei I. Loiola & M. F. Sales (sect. Rhabdophyllum) from north-eastern Brazil are described and illustrated, and their taxonomic and ecological relationships are discussed. 相似文献
73.
The effect of food deprivation on ova transport, hormonal profiles and metabolic changes was studied in 20 crossbred multiparous
sows during their second oestrus after weaning. To determine the time of ovulation, transrectal ultrasonographic examination
was performed. The sows were divided into 2 groups, one control group (C-group), which was fed according to Swedish standards,
and one experimental group (E-group). The E-group sows were deprived of food from the first morning meal after ovulation until
slaughter. Blood samples were collected every second hour from about 12 h before expected ovulation in the second oestrus
after weaning until slaughter and were analysed for progesterone, prostaglandin F2α-metabolite, insulin, glucose, free fatty acids and triglycerides. All sows were slaughtered approximately 48 h after ovulation
and the genital tract was recovered. The isthmic part of the oviduct was divided into 3 equally long segments and flushed
separately with phosphate buffered saline (PBS). Uterine horns were also flushed with PBS. A significantly greater number
of ova were found in the first and second part of the isthmus in the E-group (p = 0.05) while in the C-group most of the ova
were found in the third part of the isthmus or the uterus (p = 0.01). The level of prostaglandin F2α-metabolite was significantly higher in the E-group compared with the C-group. The concentration of progesterone increased
in both groups after ovulation but there were no significant differences between the groups. The other blood parameters showed
that the food-deprived sows were in a catabolic state. The 48 h period of fasting results, directly or indirectly in an delayed
ova transport, which may be due to a delayed relaxation in the smooth circular muscle layer of the isthmus. 相似文献
74.
Martinus AM van Boekel Erik R Vossenaar Frank HJ van den Hoogen Walther J van Venrooij 《Arthritis research & therapy》2001,3(2):1-7
This review focuses on the mechanisms of stress response in the synovial tissue of rheumatoid arthritis. The major stress factors, such as heat stress, shear stress, proinflammatory cytokines and oxidative stress, are discussed and reviewed, focusing on their potential to induce a stress response in the synovial tissue. Several pathways of stress signalling molecules are found to be activated in the synovial membrane of rheumatoid arthritis; of these the most important examples are heat shock proteins, mitogen-activated protein kinases, stress-activated protein kinases and molecules involved in the oxidative stress pathways. The expression of these pathways in vitro and in vivo as well as the consequences of stress signalling in the rheumatoid synovium are discussed. Stress signalling is part of a cellular response to potentially harmful stimuli and thus is essentially involved in the process of synovitis. Stress signalling pathways are therefore new and promising targets of future anti-rheumatic therapies. 相似文献
75.
This investigation examined the exposure of Egyptian infants to Aflatoxin M1 (AfM1) and of lactating mothers to Aflatoxin B1, using AfM1 in human milk as a biomarker for exposure to AfB1. The presence of ochratoxin A (OA) in human milk was also investigated to determine the levels of infants exposure to OA
from human milk. The results indicated that AfM1 was found in 66 (55 %) of 120 human milk samples with a mean of 0.3 ± 0.53 ng/mL (range 0.02 to 2.09 ng/mL). OA was found
in 43 (35.8 %) of 120 human milk samples with a mean of 21.1 ± 13.7 ng/mL (range 5.07 to 45.01 ng/mL), which will cause a
daily intake of OA from human milk exceeding the suggested tolerable dose of 5 ng/kg-1 of OA body weight. On the other side AfM1 was found in 25 % of blood samples (5 out of 20 samples), at a mean of 1.18 ng/mL, but it was detected only in one urine
sample (1 out of 20 samples). OA was detected only in 2 out of 13 blood samples (15.4 %) with an average 3.67 ng/mL. Whereas
OA was not detected in all analyzed urine samples. 相似文献
76.
Mitracarpus longicalyx is here described and illustrated from sandy areas of the caatingas of northeastern Brazil. The new species is similar toM. hirtus andM. megapotamicus. 相似文献
77.
78.
Raimunda Sâmia Nogueira Brilhante Pedro Henrique de Aragão Rodrigues Lucas Pereira de Alencar Giovanna Barbosa Riello Joyce Fonteles Ribeiro Jonathas Sales de Oliveira Débora de Souza Collares Maia Castelo-Branco Tereza de Jesus Pinheiro Gomes Bandeira André Jalles Monteiro Marcos Fábio Gadelha Rocha Rossana de Aguiar Cordeiro José Luciano Bezerra Moreira José Júlio Costa Sidrim 《Mycopathologia》2015,180(5-6):421-426
79.
80.
Leaf blade structure of Verbesina macrophylla (Cass.) F. S. Blake (Asteraceae): ontogeny,duct secretion mechanism and essential oil composition 下载免费PDF全文
L. D. A. Bezerra P. A. O. Mangabeira R. A. de Oliveira L. C. D. B. Costa M. Da Cunha 《Plant biology (Stuttgart, Germany)》2018,20(3):433-443
- Secretory structures are common in Asteraceae, where they exhibit a high degree of morphological diversity. The species Verbesina macrophylla, popularly known as assa‐peixe, is native to Brazil where it is widely used for medicinal purposes. Despite its potential medical importance, there have been no studies of the anatomy of this species, especially its secretory structures and secreted compounds. This study examined leaves of V. macrophylla with emphasis on secretory structures and secreted secondary metabolites.
- Development of secretory ducts and the mechanism of secretion production are described for V. macrophylla using ultrastructure, yield and chemical composition of its essential oils.
- Verbesina macrophylla has a hypostomatic leaf blade with dorsiventral mesophyll and secretory ducts associated with vascular bundles of schizogenous origin. Histochemistry identified the presence of lipids, terpenes, alkaloids and mucopolysaccharides. Ultrastructure suggests that the secretion released into the duct lumen is produced in plastids of transfer cells, parenchymal sheath cells and stored in vacuoles in these cells and duct epithelial cells. The essential oil content was 0.8%, and its major components were germacrene D, germacrene D‐4‐ol, β‐caryophyllene, bicyclogermacrene and α‐cadinol.
- Secretory ducts of V. macrophylla are squizogenous. Substances identified in tissues suggest that both secretions stored in the ducts and in adjacent parenchyma cells are involved in chemical defence. The essential oil is rich in sesquiterpenes, with germacrene D and its derivatives being notable components.