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1.
Although porcine-origin trypsin will effectively remove bovine herpesvirus 1 (BHV-1) associated with in vivo-derived embryos, TrypLE, a recombinant trypsin-like protease, has not been evaluated. In Experiment 1, 17 groups of 10 in vivo-derived embryos were exposed to BHV-1, treated with TrypLE Express or TrypLE Select (10x concentration) for varying intervals, and assayed as 2 groups of 5 embryos. TrypLE Select treatment for 5 and 10 min (two and seven groups of five embryos, respectively) effectively inactivated BHV-1. In Experiment 2, 22 groups of 10 IVF embryos were treated and assayed. Treatment with TrypLE Select for 7 and 10 min (six groups of five embryos each) and with TrypLE Select diluted 1:2 for 10 min (seven groups of five embryos) was also effective. In Experiment 3, 17 groups of 10 IVF embryos were further evaluated with TrypLE Select undiluted and diluted 1:2 for 10 min. Treatment with the diluted product was effective (18 groups of five embryos), whereas the undiluted product was not completely effective (virus isolated from 2 of 16 groups). In Experiment 4, IVF embryos were treated as described in Experiment 3 and then cultured individually or as groups of five on uterine tubal cells (UTCs) for 48 h; 60% of UTC samples associated with groups of embryos and 35% of UTC associated with individual embryo samples were positive for BHV-1. Therefore, although TrypLE Select appeared to have promise for the treatment of in vivo-derived embryos, it cannot be recommended for treatment of in vitro-derived embryos.  相似文献   

2.
We compared general behaviour trends of resampling methods (bootstrap, bootstrap with Poisson distribution, jackknife, and jackknife with symmetric resampling) and different ways to summarize the results for resampling (absolute frequency, F, and frequency difference, GC') for real data sets under variable resampling strengths in three weighting schemes. We propose an equivalence between bootstrap and jackknife in order to make bootstrap variable across different resampling strengths. Specifically, for each method we evaluated the number of spurious groups (groups not present in the strict consensus of the unaltered data set), of real groups, and of inconsistencies in ranking of groups under variable resampling strengths. We found that GC' always generated more spurious groups and recovered more groups than F. Bootstrap methods generated more spurious groups than jackknife methods; and jackknife is the method that recovered more real groups. We consistently obtained a higher proportion of spurious groups for GC' than for F; and for bootstrap than for jackknife. Finally, we evaluated the ranking of groups under variable resampling strengths qualitatively in the trajectories of "support" against resampling strength, and quantitatively with Kendall coefficient values. We found fewer ranking inconsistencies for GC' than for F, and for bootstrap than for jackknife.
© The Willi Hennig Society 2009.  相似文献   

3.
The relationships between relative brain size and both stratification and social structure were examined in a total of 82 species of anthropoids. The species were divided into a total of 42 congeneric groups which consisted of congeneric species with similar ecologies and social structures. The relative brain size (RBS) was calculated for each congeneric group in each superfamily, based on an allometric equation describing the relationship between brain weight and body weight for each superfamily. Among congeneric groups with a common category of diet, RBS was significantly greater for terrestrial groups than for arboreal groups, and for polygynous (i.e. multi-female) groups than for monogynous (single-female) groups. Furthermore, RBS was significantly and positively correlated with the size of the home range per individual for the Cercopithecoidea, and with troop size for frugivorous groups of the Ceboidea. The results obtained suggest that factors associated with terrestriality and polygyny have been involved in the increases in relative brain size of anthropoids.  相似文献   

4.
Oocyte cryopreservation and intracytoplasmic sperm injection (ICSI) are advantageous to expand their usefulness in genetic engineering. Oocytes matured for 22 hr were vitrified in droplets of cryoprotectants (3.2 M ethylene glycol (EG), 2.36 M dimethyl sulfoxide (DMSO), 0.6 M sucrose) on copper electron microscope (EM) grids. After being warmed, the oocytes were cultured in IVM medium for an additional 2 hr. Sperm treated with dithiothreitol were utilized for ICSI. Oocytes injected with sperm were activated by combination of ionomycin with cycloheximide (CHX). The ICSI oocytes were compared for the rates of pronuclear formation, development, cell number, and the ratio of ICM to those of fresh ICSI and IVF control. The proportion of 2PN formation was significantly higher in IVF control (Group 1) than those in other treated groups. Among the treated groups a significant lower 2PN formation was observed in IVF-frozen-thawed than in ICSI-fresh and frozen-thawed groups. Cleavage rates in IVF-frozen-thawed and ICSI-frozen-thawed groups were significantly lower than those of IVF control and ICSI-fresh groups. In ICSI groups, the rates of cleavage and blastocyst in fresh oocytes were significantly higher than in frozen-thawed. Development rates into blastocysts in the ICSI-fresh and frozen-thawed groups were significantly lower than that of IVF control. Total cell number was significantly lower in both frozen-thawed IVF and ICSI groups than those in IVF-control and ICSI-fresh groups. However, the rates of the remaining cells that were found in the ICM were significantly higher in both frozen-thawed IVF and ICSI than in the IVF-control and ICSI-fresh groups. The results indicated that frozen-thawed bovine oocytes were suitable for ICSI procedure.  相似文献   

5.
The use of prepacked capillary columns for immobilizing proteins and peptides for solid-phase Edman degradation is described. Capillary tubes with an internal volume of about 30 microliters are filled with glass beads bearing isothiocyanato groups (DITC-glass), aminophenyl groups (AP-glass), or aminoethylaminopropyl groups (AEAP-glass) and are sealed with porous plugs. Proteins or peptides in appropriate buffers are introduced into the columns by capillary action and are covalently coupled to the glass beads, either by reaction of lysine side-chain amino groups with DITC-glass, by carbodi-imide-mediated reaction of carboxyl groups with AP-glass, or by reaction of homoserine lactone groups with AEAP-glass. Optimization of attachment conditions is described. The capillary columns are loaded into the sequencer and, when sequencing has been completed, are discarded. This technique greatly simplifies polypeptide immobilization and is suitable for microsequencing (less than 50-1000 pmol) or macrosequencing (1-50 nmol).  相似文献   

6.
计算了汉、回、蒙古、维吾尔、侗、高山、朝鲜和壮等八个民族红细胞抗原常见等位基因数、常见血型和血型组合频率、血型相同的二人随机相遇的概率、血型组合数、常见和罕见的血型组合、AB、Rh(D-)型频率及排除亲子关系的概率。结果表明,中国北方民族的血型系统的多态程度比南方民族高。  相似文献   

7.
The onset of schooling behaviour and brain growth in larval yellowtail Seriola quinqueradiata larvae fed on Artemia enriched with oleic acid (OA), eicosapentaenoic acid (EPA) or docosahexaenoic acid (DHA) for 10 days was investigated. Larvae from the DHA groups schooled with parallel orientation while those of the EPA groups showed only aggregation. Larvae of the OA groups were dispersed. DHA and EPA groups showed significantly smaller nearest neighbour distance compared with OA groups, and DHA groups showed significantly smaller values of nearest neighbour angle compared with the other groups. The relative volume of the tectum opticus (TO) of the DHA group was significantly larger in two experiments and also the relative volume of the cerebellum (CE) of that group was significantly larger in one experiment. Dietary DHA is probably critically important for the development of the brain, particularly TO, during the larval stages, and that development of TO may be the key factor of the ontogeny of schooling behaviour.  相似文献   

8.
生态系统可以从“结构-功能-服务”3个层次来理解,其中服务是人类的主观感受或效用。维持高质量的生态系统服务还需从生态系统的自然属性入手。结构和功能是生态系统服务形成和维持的内在机制,而植物是生态系统结构和功能的核心驱动力。植物功能群具有特定功能的植物组合,其中优势植物功能群控制着生态系统的结构和功能。生态系统服务的概念、分类与植物功能群密切相关,植物功能群是生态系统与生态系统服务间更直接的桥梁。建立生态系统服务与植物功能群间的联系,使相关研究有更明确的指向,在深化理论研究的同时使研究成果更容易落地。生态系统服务的形成、维持机制与植物功能群的内在联系主要体现在4个主要方面:(1)植物功能群的内在适应性特征和外在效应是生态系统服务形成的基础;(2)植物功能群的多功能特性为生态系统服务协同提供了可能;(3)植物功能群间替代和互补效应可以提升生态系统服务质量和稳定性;(4)植物功能群能够提供基于自然的生态系统服务修复问题解决方案。  相似文献   

9.
Electrophoretic mobilities of barley mesophyll cell protoplastsmodified by chemical and enzymatic treatments were measuredin media at various pH values to elucidate the contributionof phosphate, carboxylate and amino groups to the surface chargedensity. Existence of these charged groups was confirmed byresults of treatment of protoplasts with glutaraldehyde (foramino groups), acid phosphatase (for phosphate groups) and l-ethyl-3-(3-dimethylaminopropyl)carbodi-imidetogether with glycine methyl ester (for carboxylate groups).The relative amounts of these groups were estimated from thecurves of surface charge density () vs. surface pH (pHs) ofthe treated protoplasts, in terms of simplified acid-base dissociationcurves. The estimated ratio of the amounts of phosphate, carboxylateand amino groups was approximate 0.5 :0.5 : 0.7 for the native(unmodified) barley mesophyll cell protoplasts, when the totalnegative charge on the native protoplasts was assumed to be1. (Received January 9, 1989; Accepted April 28, 1989)  相似文献   

10.
Otoliths are inner-ear structures of all teleost fish with functional importance for hearing and balance. The otoliths usually consist of aragonite, a polymorph of calcium carbonate, but may also take the form partly or entirely of vaterite, a different polymorph of calcium carbonate. Vateritic otoliths occur sporadically in wild fish, but with a higher frequency in hatchery-reared fish. Abnormal otoliths have direct consequences for the inner-ear functions of fish and may be a symptom of environmental stress. In this study, the authors assess the differences in the frequency of abnormal otoliths and degree of abnormality (% vaterite) for different groups of hatchery-reared Atlantic salmon (Salmo salar) smolt and adults. The groups differed in parental broodstock origin (number of generations in hatchery) and treatment temperature. Smolt from the same groups were also released to complete their ocean migration. The otoliths of the returning and recaptured adults were subsequently extracted to assess the difference in frequency and degree of abnormality between the adults and the smolt from corresponding groups. Return rate varied among groups (0.2%–2.6%). The frequency of vateritic otoliths was high (11.4%–64.4%) and differed among smolt groups. The lowest return rates corresponded with the highest frequency of abnormal otoliths for the groups, suggesting that abnormal otoliths may have negative consequences for marine survival. Furthermore, indications of an effect of fast growth on the formation of abnormal otoliths were found for only one of the experimental groups, and for none of the groups after correcting for Type 1 error. This contradicts previous reports, suggesting rapid growth as the main cause of abnormal otoliths. Adult return rates were generally low, but abnormal otoliths were common, with high coverage (% vaterite).  相似文献   

11.
BackgroundWe examined the association between a decline in effectance and social participation (SP) from the perspective of the number and the type of SP in a prospective cohort study.MethodsIncluded in this analysis were community-dwelling elderly aged ≥65 without dependency on the basic activities of daily living and reporting a perfect baseline effectance score (n = 4,588; mean age 72.8±5.7). SP was categorized into 5 types: neighborhood associations, hobby groups, local event groups, senior citizen clubs, and volunteer groups. Effectance was evaluated using the Tokyo Metropolitan Institute of Gerontology Index of Competence. Using logistic regression analysis, odds ratio (OR) and a 95% confidence interval (CI) for a decline in effectance were calculated. Age, family, BMI, pensions, medical history, medications, alcohol, smoking, cognitive function, depression, social support, ADL, and IADL were used as covariates.ResultsDuring the 3-year follow-up, 17.8% of eligible participants reported a decline in effectance. After adjustment for covariates, participation in various groups was associated with the preservation of effectance for both genders. Regarding the type of SP, among females, participation in neighborhood associations (OR: 0.62, 95%CI: 0.48–0.81), hobby groups (0.58, 0.43–0.77), local event groups (0.63, 0.47–0.86), and volunteer groups (0.53, 0.35–0.82) was inversely associated with a decline in effectance. Among males, the beneficial effect was more likely limited to hobby groups (0.59, 0.43–0.81) and volunteer groups (0.57, 0.39–0.83).ConclusionsOur results suggest that participation in a variety of social groups is effective for maintenance of older people’s effectance, while the beneficial effect of each type of SP on effectance is stronger for females than for males. Recommending community-dwelling elderly to participate in social groups appropriate for their gender may be effective for successful aging.  相似文献   

12.
Warwicker J 《Proteins》2011,79(12):3374-3380
Modeling charge interactions is important for understanding many aspects of biological structure and function, and continuum methods such as Finite Difference Poisson-Boltzmann (FDPB) are commonly employed. Calculations of pH-dependence have identified separate populations; surface groups that can be modeled with a simple Debye-Hückel (DH) model, and buried groups, with stronger resultant interactions that are dependent on detailed conformation. This observation led to the development of a combined FDPB and DH method for pK(a) prediction (termed FD/DH). This study reports application of this method to ionizable groups, including engineered buried charges, in staphylococcal nuclease. The data had been made available to interested research groups before publication of mutant structures and/or pK(a) values. Overall, FD/DH calculations perform as intended with low ΔpK(a) values for surface groups (RMSD between predicted and experimental pK(a) values of 0.74), and much larger ΔpK(a) values for the engineered internal groups, with RMSD = 1.64, where mutant structures were known and RMSD = 1.80, where they were modeled. The weaker resultant interactions of the surface groups are determined mostly by charge-charge interactions. For the buried groups, R(2) for correlation between predicted and measured ΔpK(a) values is 0.74, despite the high RMSDs. Charge-charge interactions are much less important, with the R(2) value for buried group ΔpK(a) values increasing to 0.80 when the term describing charge desolvation alone is used. Engineered charge burial delivers a relatively uniform, nonspecific effect, in terms of pK(a) . How the protein environment adapts in atomic detail to deliver this resultant effect is still an open question.  相似文献   

13.
In this study, the effect of intramuscular injection of human vascular endothelial growth factor (hVEGF) on neovascularization following abdominoplasty was investigated. Twenty-four Sprague-Dawley rats were divided into four groups (n = 6). Two control groups and two experimental groups were established. Abdominoplasty was performed in all rats, with division of all the perforator vessels. In the control groups, normal saline was injected into the rectus abdominis muscle, and in the experimental groups, 100 microg of VEGF and normal saline were injected into the rectus muscle. A transverse rectus abdominis musculocutaneous (TRAM) flap was harvested on day 20 and day 40 in both the control and experimental groups. The range of viability of the TRAM flap was, respectively, 0 to 20 percent (mean, 6.7 percent) and 0 to 25 percent (mean, 14.2 percent) in both short-term and long-term control groups (no VEGF injected). The study (VEGF) group demonstrated a viability of 50 to 80 percent (mean, 70 percent) for the short-term group and 50 to 85 percent (mean, 72.5 percent) in the long-term group. No wound infection was documented, and there were no deaths during the study period. There was no statistically significant difference between the short-term and long-term divisions of the groups (p < 0.01); however, significant differences were observed between the control and experimental groups (p < 0.01). The authors concluded that VEGF injection after abdominoplasty improved the percentage of TRAM flap viability. This method of delay/revascularization could be used for the difficult problem of flap viability following abdominoplasty and for high-risk patients.  相似文献   

14.
The aim of this study was to investigate whether excess of vitamin B6 leads to ultrastructural changes in cerebral cortex of forty-eight healthy albino rats which were included in the study. Saline solution was injected to to the control groups (CG-10, n = 12 for 10 days; CG-15, n = 12 for 15 days; CG-20, n=12 for 20 days). The three experimental groups (EG-10, n = 12; EG-15, n = 12; EG-20, n = 12) were treated with 5 mg/kg vitamin B6 daily for 10 days (EG-10), 15 days (EG-15) and 20 days (EG-20). Brain tissues were prepared by glutaraldehyde-osmium tetroxide double fixation for ultrastructural analysis. No significant changes were observed in the control groups. The ultrastructural analysis revealed that the numbers of damaged mitochondria, lipofuscin granules and vacuoles were significantly higher in all the experimental groups than in the control groups (p < 0.05). However, synaptic density was significantly decreased in the experimental groups as compared to the control groups (p < 0.05). The results suggest that the excess of vitamin B6 intake causes damage to the cerebral cortex due to cellular intoxication and decreased synaptic density. Thus, careful attention should be paid to the time and dose of vitamin B6 recommended for patients who are supplemented with this vitamin.  相似文献   

15.
Gametes, somatic cells and materials of animal origin in media are potential sources for introducing bovine viral diarrhea virus (BVDV) into systems for production of IVF bovine embryos. Further, the efficacy of washing and trypsin treatment for removal of BVDV from IVF embryos is questionable. Washing and trypsin treatments recommended by the International Embryo Transfer Society for in vivo-derived embryos were applied to in vitro-derived, virus-exposed, bovine embryos in this side-by-side comparison of treatments. Embryos for the study were produced in a virus-free system in which follicular oocytes were matured and fertilized in vitro and presumptive zygotes were co-cultured with bovine uterine tubal cells for 7 d. A total of 18 trials was performed, 9 using a noncytopathic BVDV and 9 using a cytopathic BVDV. In each trial, 4 equal groups of 10 or less, zona pellucida-intact embryos/ova were assembled, including 2 groups of morulae and blastocysts (M/B) and 2 groups of nonfertile or degenerated ova (NFD). Each group was prewashed and exposed to 10(4) to 10(6) TCID50/mL of either noncytopathic (SD-1) or cytopathic (NADL) BVDV for 2 h. Following in vitro viral exposure, one group of M/B and one group of NFD were washed. The other groups of M/B and NFD were trypsin-treated. Both treatments were consistent with IETS guidelines. After in vitro exposure to noncytopathic BVDV and washing, viral assays of 100% (9/9) and 78% (7/9) of the groups of M/B and NFD ova, respectively, were positive. After in vitro exposure to cytopathic BVDV and washing, viral assay of 33% (3/9) of the groups of both M/B and NFD ova were positive. After in vitro exposure to noncytopathic BVDV and trypsin treatment, viral assay of 44% (4/9) of groups of M/B and 67% (6/9) of groups of NFD ova were positive. Finally, after in vitro exposure to cytopathic BVDV and trypsin treatment, viral assay of 22% (2/9) of the groups of M/B and 44% (4/9) of the groups of NFD ova were positive. Contingency table analysis, in which data was stratified by embryo type and virus biotype, was used to compare results. While a difference existed between results of the 2 treatments of groups of M/B within the noncytopathic biotype (P = 0.01, Mantel Haenszel Chi-square), no difference was observed between comparison of treatment between all groups in both biotypes (P > 0.05).  相似文献   

16.
Five thieno[3,4-b]pyrazine-based model compounds were studied to explore the effects of the substituent groups (alkyl or aryl) on the structure, atomic charge, optical properties, ionization potential (IP), electron affinity (EA), and reorganization energy. Theoretical calculations were carried out by density functional theory (DFT) using the B3LYP hybrid function combined and CAM-B3LYP with the 6-31G(d) basis set. The lowest-lying absorption and emission spectra of 9,9'-diethylhexylfluorene-alt-5,7-dithien-2-yl-thieno[3,4-b] pyrazine (FDDTTP) with alkyl groups showed a blue-shift, while those of FDDTTP with aryl groups exhibited a red-shift. The results agree well with analytical data from reorganization energies. IPs are brought down by both alkyl and aryl groups. However, EAs are raised only by aryl units. The results indicate that aryl groups are more helpful in forming excitions for FDDTTP molecules. Consequently, FDDTTP with aryl groups are more efficient acceptor segments for designing donor-acceptor copolymers than those with alkyl groups.  相似文献   

17.
Red cell samples from persons belonging to four Amerindian linguistic groups in Colombia were investigated for genetic variants in eight blood group systems: for three of the groups investigations were extended to ten red cell enzyme and four serum protein systems. The groups studied are the Noanama (including six Empera) of the Rio Siquirisua and Rio Docampado on the Pacific lowlands and the Cofan, Ingano and Siona Indians of the Upper Rio Putumayo and its tributaries to the east of the Andes. Only blood group O was present among two of the groups and the same groups were 100% Kp(b +), k in the Kell system. Di(a +) frequencies were high in three groups and there was marked variation between groups for the MNS, Rh, P, Lewis and Duffy systems. Polymorphism in all the three linguistic groups studied for serum proteins and red cell enzymes was present only in the red cell acid phosphatase, phosphoglucomutase (locus-1) and haptoglobin systems. 6-phosphogluconate dehydrogenase was polymorphic in the Noanama, and caeruloplasmin was polymorphic in the Ingano linguistic group. In addition two persons belonging to the Cofan linguistic group revealed the presence of an “atypical” component in the lactate dehydrogenase system. No variation was found in the other six red cell enzyme and two serum protein systems. Comparison with published data on red cell enzyme and serum protein groups for other South American Amerindian populations shows the Colombian populations studied here most closely resemble the Cayapo of Brazil.  相似文献   

18.
Three genetically distinct groups of treponemes have been identified by saturation reassociation assays using 125I-labeled treponemal DNAs. The three groups are (i) virulent Treponema pallidum (Nichols strain), (ii) T. phagedenis and its biotypes Reiter and Kazan 5, and (iii) T. refringens biotypes Nichols and Noguchi. There is no detectable DNA sequence homology (less than 5%) among the three groups. The groups have distinct guanine + cytosine contents: 52.4 to 53.7% for T. pallidum, 41.5% for T. refringens, and 38 to 39% for T. phagedenis.  相似文献   

19.
The aim of this study was to determine glucose uptake patterns in exercised skeletal muscles of elite male long-distance and short-distance runners. Positron emission tomography (PET) using 18F-fluoro-2-deoxyglucose (FDG) was performed to determine the patterns of glucose uptake in lower limbs of short-distance (SD group, n=8) and long-distance (LD group, n=8) male runners after a modified 20 min Bruce treadmill test. Magnetic resonance imaging (MRI) was used to delineate the muscle groups in lower limbs. Muscle groups from hip, knee, and ankle movers were measured. The total FDG uptake and the standard uptake value (SUV) for each muscle group were compared between the 2 groups. For the SD and LD runners, the 2 major muscle groups utilizing glucose during running were knee extensors and ankle plantarflexors, which accounted for 49.3 +/- 8.1% (25.1 +/- 4.7% and 24.2 +/- 6.0%) of overall lower extremity glucose uptake for SD group, and 51.3 +/- 8.0% (27.2 +/- 2.7% and 24.0 +/- 8.1%) for LD group. No difference in muscle glucose uptake was noted for other muscle groups. For SD runners, the SUVs for the muscle groups varied from 0.49 +/- 0.27 for the ankle plantarflexors, to 0.20 +/- 0.08 for the hip flexor. For the LD runners, the highest and lowest SUVs were 0.43 +/- 0.15 for the ankle dorsiflexors and 0.21 +/- 0.19 for the hip. For SD and LD groups, no difference in muscle SUV was noted for the muscle groups. However, the SUV ratio between the ankle dorsiflexors and plantarflexors in the LD group was significantly greater than that in the SD group. We thus conclude that the major propelling muscle groups account for approximately 50% of lower limb glucose utilization during running. Thus, the other muscle groups involving maintenance of balance, limb deceleration, and shock absorption utilize an equal amount. This result provides a new insight into glucose distribution in skeletal muscle, suggesting that propellers and supporters are both energetically important during running. Furthermore, for each unit muscle volume, movers of ankle are more glucose-demanding than those of hip.  相似文献   

20.
A primary methanol extract (F-ME), secondary butanol-soluble fraction (F-BU), and lignans were prepared from forsythia fruit (Forsythia viridissima L.) and added to 0.5% (w/w) cholesterol diets for male Sprague-Dawley rats weighing 121 +/- 12 g. There were six experimental groups: a control group, 0.2%, 0.4% F-ME supplemented groups, 0.1%, 0.02% F-BU groups and 0.02% lignan group. After 3 weeks of feeding, body weight gains, serum GOT and GPT levels were not different among the groups. HDL-/total cholesterol ratios increased in the 0.2% F-BU and lignan groups compared with the control groups. Liver triglyceride level lowered in most of forsythia groups. Fecal cholesterol excretions increased in the lignan group. Arctiin isolated from the forsythia fruit reduced cholesterol and triglyceride contents in cultured HepG2 cells at 0.01-0.1 microM. These results indicated that the forsythia lignan, arctiin is effective on improving blood lipid status without a significant hepatotoxicity and is to be utilized for the functional foods for lipid-lowering action.  相似文献   

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