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1.
The aim was to verify the effect of follicle‐stimulating hormone (FSH) supplementation to α‐MEM+ or TCM199+ media on the in vitro development of ovarian preantral follicles (PFs) derived from collared peccaries. Ovaries (n = 5 pairs) were collected and divided into fragments destined to control group (non‐cultured) or treatments that were cultured for 7 days. The PFs morphology, growth and activation were evaluated by classical histology. The immunohistochemistry markers Ag‐NOR and PCNA were used for nuclear proliferation analysis, and the picrosirius red labelling was used for ovarian extracellular matrix (ECM) evaluation. After 7‐day culture, only the TCM199+ treatment maintained the proportion of intact PFs similar to day 1 (63.2%), but no differences were found among treatments (p > .05). In addition, a significant increase in the growing follicles proportion was verified for all the treatments, indicating follicular activation (p > .05). By the Ag‐NOR analysis, only the TCM199+/FSH maintained the nuclear proliferation similar to the first day (p > .05). The picrosirius red staining revealed that the ECM remained intact in all the treatments (p > .05). We suggest the use of TCM199+ medium supplemented of FSH for the in vitro development of peccaries PFs under 7‐day culturing conditions.  相似文献   
2.
Most temperate terrestrial orchids are endangered species. Attempts to produce plantlets from plants of the genus Epipactis by asexual methods have totally failed. This study was conducted using somatic embryogenesis as a rapid vegetative propagation technique for conservation of E. veratrifolia. For these purposes, effects of different types of plant growth regulators (PGRs), different types of explants, light and dark conditions, and the effect of gibberellic acid (GA3) and Paclobutrazol (PBZ) were investigated on somatic embryogenesis induction. Abscisic acid (ABA) pre-treatment effectiveness on inducting somatic embryogenesis and increasing the number of embryos per explant were investigated. Subsequently, 16 media were tested to find the best medium for plant regeneration and shoot and root proliferation. BA (3 mg L?1) resulted in a better response than the other PGRs by supporting the development of 17 embryos per protocorm. PBZ, which resulted in 11 embryos per explant, was better than GA3. FAST medium supplemented with organic substances was recognized as the best medium for plant regeneration and shoot and root proliferation. ABA pre-treatment had positive effect on somatic embryogenesis initiation. This study, for the first time, succeeded in finding a rapid and suitable protocol for propagation and genetic resource conservation of E. veratrifolia.  相似文献   
3.
The spectrum of water vapor is of fundamental importance for a variety of processes, including the absorption and retention of sunlight in Earth's atmosphere. Therefore, there has long been an urgent need for a robust and accurate predictive model for this spectrum. In our work on the high-resolution spectrum of water, we report first-principles calculations that approach experimental accuracy. To achieve this, we performed exceptionally large electronic structure calculations and considered a variety of effects, including quantum electrodynamics, which have routinely been neglected in studies of small many-electron molecules. The high accuracy of the resulting ab initio procedure is demonstrated for the main isotopomers of water.  相似文献   
4.
Direct measurements of the current-phase relation, I versus Deltaphi, for a weak link coupling two reservoirs of B-phase superfluid helium-3 (3He-B) were made over a wide range of temperatures. The weak link consists of a square array of 100-nanometer-diameter apertures. For temperatures T such that T/Tc >/= 0.6 (where Tc is the superfluid transition temperature), I approximately sin(Deltaphi). At lower temperatures, I(Deltaphi) approaches a straight line. Several remarkable phenomena heretofore inaccessible to superconducting Josephson junctions, including direct observation of quantum oscillations and continuous knowledge of Deltaphi, were also observed.  相似文献   
5.
A high-intensity laser was used to shock-compress liquid deuterium to pressures from 22 to 340 gigapascals. In this regime deuterium is predicted to transform from an insulating molecular fluid to an atomic metallic fluid. Shock densities and pressures, determined by radiography, revealed an increase in compressibility near 100 gigapascals indicative of such a transition. Velocity interferometry measurements, obtained by reflecting a laser probe directly off the shock front in flight, demonstrated that deuterium shocked above 55 gigapascals has an electrical conductivity characteristic of a liquid metal and independently confirmed the radiography.  相似文献   
6.
We studied seed morphometric characters, oil content and azadirachtin content in a medicinally important and insect repellent tree species Azadirachta indica A.Juss. Ten populations were selected from two central Indian states of Madhya Pradesh and Chhattisgarh and twenty candidate plus trees were selected from each population based on tree attributes. Azadirachtin content was estimated in seeds, in vitro shoots and callus cultures through HPLC. Significant variation(p \ 0.05) was observed in seed morphometric characters, oil content and azadirachtin content among the ten populations. Maximum value for 100 seed weight was obtained in seeds of Raigarh(30.51 g) which was on par with seeds of Bargi(28.37 g)and Chhatarpur(26.36 g). The ratio of highest kernel to seed was also obtained in seeds of Raigarh(60.11%).Kernels from Chhatarpur population recorded the highest oil content(24.20%), which was equal to that in Sihore(23.75%) and Katni(21.75%). We recorded highly significant variation in azadirachtin content in seed samples,in vitro shoot samples and callus cultures. Maximum azadirachtin was present in the seeds of Gwalior(0.882%)which was on par with azadirachtin content in seeds of Chhatarpur, Katni, Sihore, Shahdol and Chhindwara.Maximum azadirachtin in the in vitro shoots was present in the cultures of Gwalior(0.218%) which was statistically on par with Sihore(0.176%). Similarly, in callus cultures of nodal segments maximum azadirachtin was recorded in the Gwalior population(0.033%) which was statistically on par with Sihore(0.028%). The trees of Gwalior and Sihore populations can be produced in large numbers through vegetative propagation to obtain seeds with higher azadirachtin content.  相似文献   
7.
用10年生丛生竹的节片通过离体腋笋增殖和生根产生出府竹小苗。不同季节对无菌培养物的建立、腋芽发萌和初代培养的影响很大。3片丛生林中,无菌培养物的建立有差别,但腋芽发萌没有差别。用加有31.06uM BA和2.85um IAA的MS液体介质,最大的增值率为3.18;用加有20~25um IBA MS液体介质,离体生根率为66.7~77.8%。用不同的植物生长素,生根所用的天数也不同,而IBA液能在短期促进生根,仅仅为2-3周。成功炼苗后,在装有土壤、沙子和农家肥塑料袋里,离体繁殖的小苗成活率为90%,大约有2000株小苗用于野外栽植。  相似文献   
8.
The production performances of giant freshwater prawn Macrobrachium rosenbergii and Nile tilapia Oreochromis niloticus in C/N‐controlled periphyton‐based polyculture systems were evaluated in triplicate. Three different management practices were compared: the traditional practice without addition of periphyton substrates and carbohydrate (Control), addition of maize flour to maintain a carbon: nitrogen rate of 20:1 (treatment CN) and addition of both maize flour and periphyton substrates (treatment CN+P). This experiment used a pre‐optimized stocking density of tilapia and freshwater prawn by Asaduzzaman et al. Aquaculture [286 (2009) 72]. All ponds were stocked with prawn (3 m2) and monosex Nile tilapia (1 m?2). Bamboo side shoots were posted vertically into the pond bottoms as periphyton substrate covering an additional area of 171 m2 for periphyton development. A locally formulated and prepared feed containing 17% crude protein with C/N ratio close to 15:1 was applied twice daily in all ponds considering the body weight of freshwater prawn only. Water quality parameters, except total alkalinity did not vary significantly (> 0.05) among treatments. Both, organic matter and total heterotrophic bacterial loads (THB) in the sediment were significantly (P < 0.05) higher in treatment CN+P followed by treatment CN and control. Periphyton biomass in terms of dry matter and chlorophyll a values constantly decreased during the culture period. Substrates contributed 66% and 102% higher net yield of freshwater prawn than CN and control treatment respectively.  相似文献   
9.
The ballan wrasse (Labrus bergylta) is a marine fish belonging to the family Labridae characterized by 2 main morphotypes that occur in sympatry: spotty and plain. Previous studies have revealed differences in their life‐history traits, such as growth and maturation; however, the genetic relationship between forms is presently unknown. Using 20 recently developed microsatellite markers, we conducted a genetic analysis of 41 and 48 spotty and plain ballan wrasse collected in Galicia (northwest Spain). The 2 morphotypes displayed highly significant genetic differences to each other (FST = 0.018, P < 0.0001). A similar degree of genetic differentiation (FST = 0.025, P < 0.0001) was shown using the STRUCTURE clustering approach with no priors at K = 2. In this case, the frequency of spotty and plain morphotypes was significantly different (χ2 = 9.46, P = 0.002). It is concluded that there is significant genetic heterogeneity within this species, which appears to be highly associated with the spotty and plain forms, but not completely explained by them. Given the previously demonstrated biological differences between morphotypes, and the present genetic analyses, we speculate about the convenience of a taxonomic re‐evaluation of this species.  相似文献   
10.
The Iberian lynx is considered the most endangered felid species. Therefore, an ex situ conservation program was initiated to protect this species from extinction. Additional knowledge on lynx reproduction biology and reliable methods for reproductive monitoring are important for developing a captive breeding program. The aim of this study in lynx was to implement transrectal ultrasonography to visualize ovarian structures (follicles, corpora lutea) and to assess ovarian activity in addition to analysis of serum progesterone and oestradiol. Because of limited access to Iberian lynxes, the less-endangered Eurasian lynx and bobcat were also studied in this comparative study. Recent endocrinological studies based on faecal and urinary progesterone and oestrogen metabolites revealed that steroid profiles in both these species were alike and did not follow the typical pattern of other felids. Pregnancy diagnosis was not possible, since progesterone concentrations did not differ between pregnant and pseudopregnant animals. Progesterone was also detected after parturition as well as after weaning until the onset of a new oestrous cycle. In the present study, the presence of corpora lutea during the non-breeding season was confirmed by ultrasonography and by elevated serum levels of progesterone averaging 3.56 ± 1.3 ng/ml in Eurasian and 6.1 ± 0.26 ng/ml in Iberian lynx, respectively. The ultrasonographical findings on the ovarian structures suggest strongly that corpora lutea developed after ovulation stay active until November and regress before the onset of the next oestrus.  相似文献   
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