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71.
We studied the volatile composition and sexual morphs of Nephelium lappaceum flowers from two orchards, and investigated the choice behavior of the honey bee, Apis mellifera toward the floral extracts from both locations. Our results showed significant differences in chemical composition and sexual morphs; only the hermaphrodite flowers from the Herradero orchard produced limonene and α-pinene and had longer peduncle and sepal than flowers from the Metapa orchard; on the other hand, the hermaphrodite flowers from the Metapa orchard had longer gynoecium. In the behavioral experiment the extracts from the Herradero orchard seemed to give A. mellifera foragers better cues for orientation to food sources, perhaps due to the presence of limonene and α-pinene, which are absent in the samples from Metapa. Such differences in both orchards could affect pollinator attraction and ultimately seed set and productivity.  相似文献   
72.
Stenocereus zopilotensis Arreola-Nava and Terrazas, a new species from the Zopilote Canyon, municipality of Zumpango del Rio in the center of the state of Guerrero (Mexico), is described and illustrated. This new species is compared toStenocereus quevedonis J. G. Ortega,S. fricii Sánchez-Mej., andS. pruinosus (Otto) Buxb. based on morphological similarity. Moreover, the new species grows sympatrically withS. pruinosus.  相似文献   
73.
The study of the clinical isolates of Cryptococcus neoformans from 83 Brazilian patients with disseminated cryptococcosis showed that 75 were C. neoformans var. neoformans and 8 were var. gattii. Twenty-seven isolates were serotyped; all 19 var. neoformans were serotype A and all 8 var. gattii were serotype B. The correlation of the varieties of C. neoformans with the presence or not of hosts predisposing conditions to the mycosis showed that: (1) cryptococcosis caused by gattii variety occurred in 7 (58.3%) of the 12 nonimmunosuppressed patients, and (2) cryptococcosis caused by neoformans variety occurred in 65 (98.5%) of the 66 AIDS patients and in all 5 patients with other immunosuppressive conditions. The comparison of the distribution of the gattii and neoformans varieties between the nonimmunosup-pressed and immunosuppressed patients showed a significant statistical difference (p < 0.01).  相似文献   
74.
A total of 360 pacus (Piaractus mesopotamicus) were used to study vascular permeability (VP) and inflammatory cell component (CC) in induced aerocystitis in P. mesopotamicus through inoculation of inactivated Aeromonas hydrophila, and the effect of steroidal and nonsteroidal anti-inflammatory drugs. It was observed that after inoculation of A. hydrophila, the maximum VP occurred 180 min post-stimulus (MPS). Pretreatment with anti-inflammatory drugs inhibited VP, and the inhibitory effect of dexamethasone was seen earlier than the effects caused by meloxicam and indomethacin. Inoculation of the bacterium caused a gradual increase in the accumulation of cells, which reached a maximum 24 h post-stimulus (HPS). Pretreatment with dexamethasone, indomethacin and meloxicam reduced the accumulation of lymphocytes, thrombocytes, granulocytes and macrophages. There was no significant difference between the different doses of the drugs tested. The results suggest that eicosanoids and pro-inflammatory cytokines participate in chemical mediation in acute inflammation in pacus.  相似文献   
75.
The Sp1 binding site polymorphism in collagen type I alpha 1 gene (COLIA1) has been associated with osteoporosis (OP) and bone mineral density (BMD). The aim of this study was to explore the association of this polymorphism with OP and BMD in the Mexican population by polymerase chain reaction and restriction fragment length polymorphism (PCR–RFLP) procedure. Allelic and genotypic frequencies from the Sp1 polymorphism were determined in 100 women with OP, 100 women without OP and 500 subjects from general Mexican population (GMP). Distribution of Sp1 polymorphism was in Hardy–Weinberg equilibrium. In spite of population structure due to racial mix in Mexican population, associations with OP were demonstrated. The frequency of “s” allele was significantly higher in women with OP (35%) than in women without OP (11%; P < 0.00001). Interestingly, “ss” genotype, was exclusive of women with OP and was associated with low BMD (0.588 ± 0.077 g/cm2) in contrast to “SS” genotype (0.733 ± 0.039 g/cm2; P = 0.0001). This work confirms the association of Sp1 polymorphism with low BMD and OP in Mexican population and make sure to use Sp1 as a genetic marker for OP in our population.  相似文献   
76.
The aim of this study was to determine the time taken for complete uterine involution in Bulgarian Murrah buffaloes following normal parturition and oxytocin stimulated milking; and to establish the time course of the change in size of the uterine horns, the cervix and caruncles between parturition and involution by means of ultrasonography. There were 17 animals in the study aged 3-6 years and average parity of 2.17 ± 0.18. They were administered 20 IU oxytocin 15 min before each milking. Rectal palpation and transrectal ultrasonography were performed at 3 d intervals from Days 1 to 34 post partum. The involution of the non-gravid and gravid uterine horns, and the cervix was complete by Days 22 and 25 post partum when their diameters were 2.7 ± 0.4 cm, 2.8 ± 0.3 cm and 3.12 ± 0.4 cm, respectively. Caruncles underwent rapid regression until Day 10 post partum. It was not possible to determine the dimensions of the caruncles after that time. The cumulative percentage of animals whose uterus was located in the pelvic cavity increased from 24% at Day 10 post partum to 100% at Day 34 post partum. The combination of rectal palpation and transrectal ultrasonography provided a reliable method of evaluating changes in the uterus over time and determining the time of uterine involution. The present study showed that complete uterine involution, with the uterus located in the pelvic cavity, was achieved by Day 34 after parturition in all 17 Bulgarian Murrah buffaloes treated with oxytocin before milking.  相似文献   
77.
Tropical forests around the world have been lost, mainly because of agricultural activities. Linear elements like riparian vegetation in fragmented tropical landscapes help maintain the native flora and fauna. Information about the role of riparian corridors as a reservoir of bat species, however, is scanty. We assessed the value of riparian corridors on the conservation of phyllostomid bat assemblage in an agricultural landscape of southern Mexico. For 2 years (2011–2013), mist‐netting at ground level was carried out twice during the dry season (December to May) and twice during the wet season (June to November) in different habitats: (1) riparian corridors in mature forest, (2) riparian corridors in pasture, (3) continuous forest away from riparian vegetation, and (4) open pastures. Each habitat was replicated three times. To determine the influence of vegetation structure on bat assemblages, all trees (≥10 cm dbh) were sampled in all habitats. Overall, 1752 individuals belonging to 28 species of Phyllostomidae were captured with Sternodermatinae being the most rich and abundant subfamily. Riparian corridors in mature forest and pastures had the greatest species richness and shared 65% of all species. Open pastures had the lowest richness and abundance of bats with no Phyllostominae species recorded. Six of the 18 species recorded could be considered as habitat indicators. There was a positive relationship between bat species composition and tree basal area. Our findings suggest that contrary to our expectations, bats with generalist habits and naturally abundant could be useful detector taxa of habitat modification, rather than bats strongly associated with undisturbed forest. Also in human‐dominated landscapes, the maintenance of habitat elements such as large trees in riparian corridors can serve as reservoirs for bat species, especially for those that are strongly associated with undisturbed forest.  相似文献   
78.
Caveolae constitute membrane domains critical for the organization and synchronization of different signaling molecules related to numerous cell processes such as cell migration, invasion, and differentiation. Caveolin-1 (Cav-1) is the main integral membrane protein of these domains. Recently, it was found that a normal expression of aquaporin-3 (AQP3) is required for extravillous trophoblast (EVT) cell migration. Our aim was to investigate the role of caveolae in the migration, invasion, and endovascular differentiation of human EVT cells during placentation and its interaction with AQP3. EVT cells (Swan 71 cell line) were cultured in complete Dulbecco's modified Eagle's medium–nutrient mixture F12 and treated with 5 mM methyl-β-cyclodextrin (MβCD) to disrupt caveolae. We found that after MβCD treatment, Cav-1 protein was undetectable. In this condition, the ability of the cells to migrate was significantly decreased compared with the control cells, while no differences were observed in the number of invading cells and the metalloproteinases activity between control and MβCD-treated cells. Surprisingly, the disruption of caveolae significantly enhanced EVT endovascular differentiation. On the contrary, the silencing of AQP3, negatively affected tube-like formation. The theoretical analysis of the primary sequence of AQP3 protein revealed a putative Cav-1-binding site. In addition, immunoprecipitation and double immunofluorescence assays showed that AQP3 colocalized with Cav-1. These results showed that during placentation an intact caveola in EVT cells may be necessary for AQP3 and Cav-1 interaction and any perturbations might result in serious pregnancy disorders.  相似文献   
79.
Prosopis flexuosa trees in the Monte Desert grow in dune and inter-dune valleys, where the water table is located at 6–14 m depth. We asked whether trees in the dunes, which are less likely to access the water table, present a coarse surface root architecture that might favor the exploration / exploitation of dune resources, compensating for water table inaccessibility. We characterized the architecture of surface roots of valley and dune trees, together with the soil environment. The dune held 50 % less and deeper gravimetric soil water (along a 4 m profile), 3-times less organic matter, 2-times less available phosphorous, and a sharper contrast of ammonium and nitrate concentration between plant canopies and uncovered soil than the valley. Coarse surface roots of dune trees were highly branched and grew tortuously at 0.56?±?0.16 m depth before sinking downward near the tree crown, suggesting an intensive exploitation of the ephemeral, deep, and canopy-linked resources. In contrast, trees from the valley spread their profuse and less branched surface roots mainly horizontally at 0.26?±?0.08 m depth, several meters outside the crown probably exploring this resource-rich site. A model for the environmental control of root architecture together with potential ecological effects is discussed.  相似文献   
80.
Intralocus sexual conflict (IaSC) occurs when selection at a given locus favors different alleles in males and females, placing a fundamental constraint on adaptation. However, the relative impact of IaSC on adaptation may become reduced in stressful environments that expose conditionally deleterious mutations to selection. The genetic correlation for fitness between males and females (rMF) provides a quantification of IaSC across the genome. We compared IaSC at a benign (29°C) and a stressful (36°C) temperature by estimating rMFs in two natural populations of the seed beetle Callosobruchus maculatus using isofemale lines. In one population, we found substantial IaSC under benign conditions signified by a negative rMF (?0.51) and, as predicted, a significant reduction of IaSC under stress signified by a reversed and positive rMF (0.21). The other population displayed low IaSC at both temperatures (rMF: 0.38; 0.40). In both populations, isofemale lines harboring alleles beneficial to males but detrimental to females at benign conditions tended to show overall low fitness under stress. These results offer support for low IaSC under stress and suggest that environmentally sensitive and conditionally deleterious alleles that are sexually selected in males mediate changes in IaSC. We discuss implications for adaptive evolution in sexually reproducing populations.  相似文献   
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