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1.
农牧结合生态工程的基本理论与实践   总被引:6,自引:0,他引:6  
农牧结合生态工程是一个复杂的农业生态、经济和技术系统工程,它由植物(种植业)、动物(养殖业)和微生物(连接种养业)3个子系统组成,其关键是建设一个以"四、三、二、一"畜牧业生产模式为主要内容的高效节粮型畜牧生态工程,它要求用尽可能少的自然资源,在尽可能短的周期内,生产尽可能多而优的农(牧)产品,以获取尽可能高的经济效益,达到或维持尽可能最佳的生态平衡.  相似文献   

2.
Ethnobotanical study of plants revealed that the local community of Ghalegy, District Swat, invariably uses 126 species of 59 families for various purposes. Based on their traditional local uses, fifty-seven species (45.2%) were classifted as medicinal, forty-seven as fire wood (37.3 % ), forty-five as forage (35.7 % ), twenty-eight as honey bee species (22.2%), twenty-seven as vegetable species (21.4%), 25 as edible fruits (14 wild and llcultivated), thirteen as timberwood (10.3%), twelve as ornamental (9.5%), eleven as furniture wood, ten as shelter and thatch makers (7.9%), ten as fencing (7.9%), five as poisonous (4%), four as religious/superstitious species, three species used in making hand sticks and wooden tools (2.4%), three as utensil cleaner species (2.4%), three as evil repellent and one as fish poisoning species. The area is in plant resources and traditional knowledge but it needs ecological management for its sustainability.  相似文献   

3.
Background Lysine succinylation is one of the reversible protein post-translational modifications (PTMs), which regulate the structure and function of proteins. It plays a significant role in various cellular physiologies including some diseases of human as well as many other organisms. The accurate identification of succinylation site is essential to understand the various biological functions and drug development.Methods In this study, we developed an improved method to predict lysine succinylation sites mapping on Homo sapiens by the fusion of three encoding schemes such as binary, the composition of k-spaced amino acid pairs (CKSAAP) and amino acid composition (AAC) with the random forest (RF) classifier. The prediction performance of the proposed random forest (RF) based on the fusion model in a comparison of other candidates was investigated by using 20-fold cross-validation (CV) and two independent test datasets were collected from two different sources.Results The CV results showed that the proposed predictor achieves the highest scores of sensitivity (SN) as 0.800, specificity (SP) as 0.902, accuracy (ACC) as 0.919, Mathew correlation coefficient (MCC) as 0.766 and partial AUC (pAUC) as 0.163 at a false-positive rate (FPR) = 0.10 and area under the ROC curve (AUC) as 0.958. It achieved the highest performance scores of SN as 0.811, SP as 0.902, ACC as 0.891, MCC as 0.629 and pAUC as 0.139 and AUC as 0.921 for the independent test protein set-1 and SN as 0.772, SP as 0.901, ACC as 0.836, MCC as 0.677 and pAUC as 0.141 at FPR = 0.10 and AUC as 0.923 for the independent test protein set-2. It also outperformed all the other existing prediction models.Conclusion The prediction performances as discussed in this article recommend that the proposed method might be a useful and encouraging computational resource for lysine succinylation site prediction in the case of human population.  相似文献   

4.
Ethnobotanical study of plants revealed that the local community of Ghalegy, District Swat, invariably uses 126 species of 59 families for various purposes. Based on their traditional local uses, fifty- seven species ( 4512%) were classified as medicinal, forty-seven as fire wood ( 3713%) , forty- five as forage ( 3517%) , twenty- eight as honey bee species ( 2212%) , twenty- seven as vegetable species ( 2114%) , 25 as edible fruits ( 14 wild and 11cultivated) , thirteen as timber wood ( 1013%) , twelve as ornamental ( 91 5%) , eleven as furniture wood, ten as shelter and thatch makers ( 719%) , ten as fencing ( 719%) , five as poisonous ( 4%) , four as religiousPsuperstitious species, three species used in making hand sticks and wooden tools ( 21 4%) , three as utensil cleaner species ( 214%) , three as evil repellent and one as fish poisoning species. The area is in plant resources and traditional knowledge but it needs ecological management for its sustainability.  相似文献   

5.
核受体是一类高度保守的配体依赖性转录因子家族,在哺乳动物发育、繁殖、免疫应答、心血管功能、组织生长、肿瘤形成、外源物清除及糖类和脂质代谢等生理过程中发挥重要作用。机体对外源物质的清除主要是由孕烷X受体等核受雄介导的。孕烷X受体最早是作为外源物感受器而被研究的,可以被大多数亲脂性药物等外源性化合物及一些内源性化合物如胆汁酸等结构差异很大的配体激活,进而与视黄醇类X受体等形成异源二聚体,结合在ER6、XREM等DNA元件上,调控下游靶基因(包括一相代谢酶、二相结合酶及药物转运体等基因)的表达。此外,孕烷X受体在能量代谢和免疫反应中也有重要作用,参与某些代谢疾病的发生发展,且已在动物模型中被证明是Ⅱ型糖尿病、血脂异常、肥胖症和动脉粥样硬化等代谢疾病治疗的有效靶标。我们主要就其发现、结构、组织分布、作用方式、自身表达的调节等方面的最新研究进行综述。  相似文献   

6.
J.E. Purkyn? was the first to discover, by achromatic microscopy of stained and fixed as well as of fresh material, that animal tissues in general, and those of the central nervous system in particular, are made up of cells, as are those of plants. His discoveries laid the foundations of modern research on the ultrastructure and biophysies of the cerebellar neurons which bear his name, as well as on other types of neurons, in vitro as well as in vivo.  相似文献   

7.
Prion protein modifies TGF-beta induced signal transduction   总被引:1,自引:0,他引:1  
Members of the transforming growth factor-beta (TGF-beta) superfamily regulate a multitude of cellular processes as well as the expression of various proteins such as, e.g., matrix metalloproteinases (MMPs). These endopeptidases selectively degrade components of the extracellular matrix as well as non-matrix substrates like growth factors and cell surface receptors. MMPs are activated during embryonic development, morphogenesis, and tissue resorption/remodeling as well as in pathological conditions such as deranged wound healing and cancer metastasis. In this report we demonstrate that over-expression of cellular prion protein in mouse mammary gland epithelial cells is able to modulate TGF-beta induced signal transduction leading to a synergistic increase of secreted MMP-2 activity. This correlates with elevated substrate detachment of cells grown as an epithelial monolayer as well as interfering with morphogenesis of cells cultured in a three-dimensional collagen type I matrix.  相似文献   

8.
The asymmetric leaves 1 ( as1 ) and as2 mutants of Arabidopsis thaliana exhibit pleiotropic phenotypes. Expression of a number of genes, including three class-1 KNOTTED -like homeobox ( KNOX ) genes ( BP , KNAT2 and KNAT6 ) and ETTIN / ARF3 , is enhanced in these mutants. In the present study, we attempted to identify the phenotypic features of as1 and as2 mutants that were generated by ectopic expression of KNOX genes, using multiple loss-of-function mutations of KNOX genes as well as as1 and as2 . Our results revealed that the ectopic expression of class-1 KNOX genes resulted in reductions in the sizes of leaves, reductions in the size of sepals and petals, the formation of a less prominent midvein, the repression of adventitious root formation and late flowering. Our results also revealed that the reduction in leaf size and late flowering were caused by the repression, by KNOX genes, of a gibberellin (GA) pathway in as1 and as2 plants. The formation of a less prominent midvein and the repression of adventitious root formation were not, however, related to the GA pathway. The asymmetric formation of leaf lobes, the lower complexity of higher-ordered veins, and the elevated frequency of adventitious shoot formation on leaves of as1 and as2 plants were not rescued by multiple mutations in KNOX genes. These features must, therefore, be controlled by other genes in which expression is enhanced in the as1 and as2 mutants.  相似文献   

9.
Kuhnle  U.  Schwarz  H. P.  Löhrs  U.  Stengel-Ruthkowski  S.  Cleve  H.  Braun  A. 《Human genetics》1993,92(6):571-576
We report on 46,XX true hermaphroditism and 46,XX maleness coexisting in the same pedigree, with maternal as well as paternal transmission of the disorder. Molecular genetic analysis showed that both hermaphrodites as well as the 46,XX male were negative for Y-chromosomal sequences. Thus, this pedigree is highly informative and allows the following conclusions: first, the maternal as well as paternal transmission of the disorder allows the possibility of an autosomal dominant as well as an X-chromosomal dominant mode of inheritance; second, testicular determination in the absence of Y-specific sequences in familial 46,XX true hermaphrodites as well as in 46,XX males seems to be due to the varying expression of the same genetic defect; and third, there is incomplete penetrance of the defect.  相似文献   

10.
1,2,3,4-Tetra-O-acetyl-5-thio-D-ribopyranose as well as its 1-bromide were used as donors in the reaction with 4-cyano- and 4-nitrobenzenethiol, to give the corresponding thioglycosides in different anomeric ratios depending on the reaction conditions. Zemplén deacetylation afforded 4-cyanophenyl as well as 4-nitrophenyl 1,5-dithio-alpha- and beta-D-ribopyranosides, respectively. 1,3,4-Tri-O-acetyl-2-deoxy-5-thio-D-erythro-pentopyranose was synthesized from methyl 2-deoxy-D-erythro-pentofuranoside and was coupled with 4-cyano- and 4-nitrobenzenethiol to give anomeric mixtures from which 4-cyanophenyl as well as 4-nitrophenyl 1,5-dithio-beta-D-erythro-pentopyranosides were isolated after deacetylation. 1,4-Di-O-acetyl-2,3-dideoxy-5-thio-D-glycero-pentopyranose was obtained starting from 1,2,5,6-di-O-isopropylidene-D-mannitol and used as the donor in the glycosylation reaction with 4-cyano- and 4-nitrobenzenethiol. The resulting anomeric mixtures were separated to give, after deacetylation, 4-cyanophenyl as well as 4-nitrophenyl 2,3-dideoxy-1,5-dithio-beta-D-glycero-pentopyranosides. All of these thioglycosides showed significant antithrombotic activity on rats after oral administration.  相似文献   

11.
Phosphonate utilization by bacteria.   总被引:17,自引:4,他引:13       下载免费PDF全文
Bacteria able to use at least one of 13 ionic alkylphosphonates of O-alkyl or O,O-dialkyl alkylphosphonates as phosphorus sources were isolated from sewage and soil. Four of these isolates used 2-aminoethylphosphonic acid (AEP) as a sole carbon, nitrogen, and phosphorus source. None of the other phosphonates served as a carbon source for the organisms. One isolate, identified as Pseudomonas putida, grew with AEP as its sole carbon, nitrogen, and phosphorus source and released nearly all of the organic phosphorus as orthophosphate and 72% of the AEP nitrogen as ammonium. This is the first demonstration of utilization of a phosphonoalkyl moiety as a sole carbon source. Cell-free extracts of P. putida contained an inducible enzyme system that required pyruvate and pyridoxal phosphate to release orthophosphate from AEP; acetaldehyde was tentatively identified as a second product. Phosphite inhibited the enzyme system.  相似文献   

12.
The PPO activity and content of phenolic compounds were estimated during the different growing seasons and developmental age of shoots in seven grape genotypes. Both, the total phenol content and catecholase activity were found significantly affected by the growing season, developmental age of shoot and the genotype. But, season as well as age of shoot could not influence cresolase activity. Spring as season; 30 days of sprouting as age; Gold and Anab-e-Shahi as genotypes were found better in comparison to summer as season and 15 days of sprouting as age in respect to level of phenols and PPO activity.  相似文献   

13.
健康仔猪肠道乳杆菌黑龙江地方株的鉴定与种属分析   总被引:2,自引:1,他引:1  
为了从健康仔猪肠道中分离筛选用于研制微生态制剂的乳酸杆菌菌株,选择黑龙江省大庆、哈尔滨及宝泉岭地区部分猪场,采集12-60日龄健康仔猪肠道粪样64份。选用MRS乳酸杆菌专用培养基分离培养乳酸杆菌,通过分离株的形态特征和培养特性筛选出革兰阳性,厌氧,无芽胞杆菌48株。再通过生化试验鉴定和PCR种属分析,确定18株为乳酸杆菌。其中,罗伊乳杆菌7株,嗜酸乳杆菌5株,约氏乳杆菌2株,短乳杆菌1株,干酪乳杆菌假植物亚种1株,植物乳杆菌1株,詹氏乳杆菌1株。  相似文献   

14.
Microbial fermentation is emerging as an increasingly important resource for the production of fatty acids to serve as precursors for renewable diesel as well as detergents, lubricants and other industrial chemicals, as an alternative to traditional sources of reduced carbon such as petroleum. A major disadvantage of fuels derived from biological sources is their undesirable physical properties such as high cloud and pour points, and high viscosity. Here we report the development of an Escherichia coli strain that efficiently produces anteiso-branched fatty acids, which can be converted into downstream products with lower cloud and pour points than the mixtures of compounds produced via the native metabolism of the cell. This work addresses a serious limitation that must be overcome in order to produce renewable biodiesel and oleochemicals that perform as well as their petroleum-based counterparts.  相似文献   

15.
Podosomes have been known for several decades as micron-sized, F-actin-rich structures that play a pivotal role in cell migration and invasion, as they are able to mediate both cell-matrix attachment as well as extracellular matrix degradation. Particularly in monocytic cells, podosomes have been shown to fulfill a variety of additional functions such as sensing of substrate rigidity and topography, or cell-cell fusion. Increasing evidence now points to the involvement of podosome-like structures also during phagocytosis by immune cells such as macrophages, dendritic cells, and neutrophils. Here, we compare the different cell models and experimental set ups where “phagocytic podosomes” have been described. We also discuss the composition and architecture of these structures, their potential involvement in mechanosensing and particle disruption, as well as the pros and cons for addressing them as bona fide podosomes.  相似文献   

16.
Cyanobacteria (blue-green algae) are 02-evolving photosynthesizing prokaryotes that have an extensive history of use as a human food source and as a fertilizer in rice fields. They have also been recognized as an excellent source of vitamins and proteins and as such are found in health food stores in North America and elsewhere. Cyanobacteria have a great deal of potential as a source of fine chemicals, as a biofertilizer and as a source of renewable fuel. This potential is being realized as data from research in the areas of the physiology and chemistry of these organisms are gathered and as the knowledge of cyanobacterial genetics and genetic engineering increases. We review, here, the present (and possible future) uses of cyanobacteria and assess the state of the art with respect to the genetic manipulation of cyanobacteria.  相似文献   

17.
The SLX4/FANCP tumor suppressor has emerged as a key player in the maintenance of genome stability, making pivotal contributions to the repair of interstrand cross-links, homologous recombination, and in response to replication stress genome-wide as well as at specific loci such as common fragile sites and telomeres. SLX4 does so in part by acting as a scaffold that controls and coordinates the XPF–ERCC1, MUS81–EME1, and SLX1 structure-specific endonucleases in different DNA repair and recombination mechanisms. It also interacts with other important DNA repair and cell cycle control factors including MSH2, PLK1, TRF2, and TOPBP1 as well as with ubiquitin and SUMO. This review aims at providing an up-to-date and comprehensive view on the key functions that SLX4 fulfills to maintain genome stability as well as to highlight and discuss areas of uncertainty and emerging concepts.  相似文献   

18.
《Free radical research》2013,47(1):795-807
In the past decades air pollution has increased worldwide. We also gained more insight into the complex interactions between different air pollutants in the atmosphere as well as their effects on living cells and organisms. It also has been unequivocally shown by several groups in different countries that oxy radicals play an outstanding role in the interconversion of air pollutants as well as during the manifestation of toxic effects. Not only living systems are affected by air pollutants, but also inorganic systems such as buildings and sculptures. In the following overview the most important reactions occuring in the atmosphere as well as effects of oxidative gaseous compounds and particles such as diesel soot and asbestos will be discussed.  相似文献   

19.
Papain-like cysteine proteases are the most numerous family of the cysteine protease class. They are expressed throughout the animal and plant kingdoms as well as in viruses and bacteria. More recently, this protease family has drawn attention as a potential pharmaceutical drug target in diseases characterized by excessive extracellular matrix degradation such as in osteoporosis, arthritis, vascular diseases, and cancer. Moreover, papain-like cysteine proteases have been identified as critical components of the life cycle and invasive potential of various human and live stock pathogens as well as major allergens. Therefore, this protease class is rigorously studied and requires sufficient amounts of protease protein to analyze structure-activity relationships, their 3-D structures as well as to screen for and optimize potent and selective inhibitors. This review summarizes approaches to generate active papain-like cysteine proteases by heterologous expression in a variety of expression systems.  相似文献   

20.
The rat mutant allele as is located on chromosome 12. Homozygous (as/as) males show arrested spermatogenesis, mainly at the pachytene spermatocyte stage. It is not clear whether this defective spermatogenesis is caused by a failure in a somatic cell component that supports spermatogenesis or in the germ cell itself. Spermatogonial transplantation was performed to identify the genetically defective site in the as/as testis. In experiment 1, germ cells collected from as/as testes were transplanted into the testes of immunodeficient mice and normal rats. In experiment 2, normal rat germ cells were transplanted into as/as testes. The results of experiment 1 showed arrest of spermatogenesis at the pachytene spermatocyte stage, accompanied by a characteristic morphological feature, i.e., the formation of inclusion-like bodies in the cytoplasm, in both rat and mouse recipients. These results revealed the intrinsic effect of the mutant gene(s) on germ cells. In experiment 2, no restoration of spermatogenesis was detected in the recipient testes despite thorough histological examination. These results suggest that defects in a somatic cell component in as/as testes prevent the donor germ cells from colonizing and regaining their spermatogenetic ability. When the seminiferous epithelium of the as/as testis was examined by electron microscopy, no morphological abnormalities, including the formation of ectoplasmic specializations between adjacent Sertoli cells, were observed in the somatic cell components. However, when cytochrome c was applied as a tracer material, it penetrated the tight junctions between the Sertoli cells, indicating dysfunction of the blood-testis barrier in the as/as testis. The lack of restoration of spermatogenesis in the as/as testis after transplantation of normal germ cells may have been caused by the unfavorable environment in the seminiferous epithelium resulting from the incomplete barrier system between adjoining Sertoli cells. The gene(s) at the as locus may have a role in both germ cell differentiation and the establishment of the blood-testis barrier.  相似文献   

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