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1.
From the diversity found among palms the following evolutionary trends are suggested:habit: from sympodial to monopodial;size: from moderate toward large and also toward small;stem: from unbranched to dichotomously branched, from little to much sclerenchyma, from short to elongate internodes;leaf: from an undivided eophyll to a palmate, costapalmate, pinnately ribbed or pinnate blade; from undivided and plicate to divided along the adaxial rib (“induplicate”) or along the abaxial rib (“reduplicate”); from pinnate to bipinnate or to pinnae onceor twicedivided longitudinally; from sheath split opposite the petiole to sheath tubular; from marcescent to deciduous; from central vascular bundles of the petiole with a single phloem strand to two phloem strands;inflorescence units: from moderately branched to spicate or less frequently to more diffusely branched, from one unit per leaf axil to more than one per axil, from among the leaves to below them or to above them in a compound terminal inflorescence, from pleonanthic to hapaxanthic;prophyll: from completely to incompletely encircling the peduncle, from incompletely to completely sheathing in bud;bracts: from conspicuous to small or absent at maturity, first peduncular bract from tubular and open at the apex to completely enclosing the inflorescence in bud, and then from ungrooved to deeply plicate;flower arrangement: from solitary, pedicellate, bracteolate flowers to a sympodial cincinnus of 2 or 3 or more, or to a short monopodial axis of 2–4 or more;bracteoles: from sheathing and prophyllate to completely closed or to incompletely developed or absent;flowers: from bisexual to unisexual, then associated with polygamy or monoecism to dioecism;perianth: from trimery to dimery or tetramery to decamery or to reduced and monochlamydeous;sepals: from distinct and imbricate to connate or separated;petals: from distinct and imbricate to valvate, or strongly imbricate, or connate; from small and ovate to large and variously shaped, or to small;stamens: from 6 to 3 or to more than 6 (to 950+);filaments: from relatively slender and distinct to broad and thick, and often connate or adnate to the perianth or both;staminodes: from stamenlike with abortive anthers only, to short teeth, or to a cupule at the base of the ovary, or to absent;pollen: from monosulcate to trichotomosulcate to dicolpate to monocolpate, diporate, or triporate;gynoecium: from apocarpous to syncarpous, from thin walls to thick, variously specialized walls;carpels or locules: from 3 to 2-1 or to 4–10;ovules: from moderate to small or to large, from anatropous to hemianatropous to campylotropous to orthotropous;pistillode: from only slightly modified from the gynoecium to vestigial or lacking or rarely to prominent;fruit: from fleshy to dry and fibrous;endocarp: from little differentiated or thin, to thick and hard, and sometimes with a pore or operculum over the embryo;seed: from moderate to small or to very large, from entire to dissected, bilobed, or perforate;endosperm: from homogeneous to invaginated or ruminate;germination: from remotetubular or -ligular to adjacent-ligular;chromosome complement: fromn = 18 ton = 17, 16, 15, 14, 13.  相似文献   

2.
Martin Klingenberg 《BBA》2010,1797(6-7):579-594
Having worked for 55 years in the center and at the fringe of bioenergetics, my major research stations are reviewed in the following wanderings: from microsomes to mitochondria, from NAD to CoQ, from reversed electron transport to reversed oxidative phosphorylation, from mitochondrial hydrogen transfer to phosphate transfer pathways, from endogenous nucleotides to mitochondrial compartmentation, from transport to mechanism, from carrier to structure, from coupling by AAC to uncoupling by UCP, and from specific to general transport laws. These wanderings are recalled with varying emphasis paid to the covered science stations.  相似文献   

3.
Summary Mineral nitrogen and potassium lost from the Eastern Flevoland polder and from the North Eastern polder were estimated at regular intervals by determining the amounts of soluble nitrogen and potassium in the water which had been admitted by locks and inlets and discharged by pumping stations and subtracting nitrogen and potassium added in the rain. From 1959 to 1966 the nett annual losses of nitrogen in the discharged water from various pumping stations in Eastern Flevoland ranged from 18.9 to 33.2 (average 25.2) kg N per ha. Similarly in the North Eastern polder from 1963 to 1966 the nett annual losses ranged from 16.7 to 33.2 (average 22.1) kg N per ha. Rainfall added annually between 4.8 and 11.8 (average 8.6) kg N per ha to both polders. Nett losses from Eastern Flevoland ranged from 9.2 to 21.9 (average 15.8) kg per ha and from the North Eastern polder from 10.1 to 24.0 (average 14.9) kg N per ha, annually. Drainage water contained principally nitrate nitrogen, whereas the discharged water in many cases contained both ammonium and nitrate nitrogen, and often more ammonium than nitrate, presumably because the composition of the mineral nitrogen in the waterways is changed by the growth and death of algae. From 1962 to 1966 the discharged water removed potassium from the Eastern Flevoland polder in amounts ranging from 105 to 226 (average 162) kg K per ha annually. During 1963–1964, amounts lost from the North Eastern polder ranged from 47 to 71 (average 59) kg K per ha each year. The rain added from 4.5 to 10.7 (average 6.9) kg K per ha annually to both polders. Nett losses from Eastern Flevoland ranged from 99 tot 219 (average 156) kg K per ha and from the North Eastern polder from 41 to 67 (average 54) kg K per ha annually.  相似文献   

4.
Rampitsch C  Bykova NV 《Proteomics》2012,12(4-5):673-690
The study of plant disease and immunity is benefiting tremendously from proteomics. Parallel streams of research from model systems, from pathogens in vitro and from the relevant pathogen-crop interactions themselves have begun to reveal a model of how plants succumb to invading pathogens and how they defend themselves without the benefit of a circulating immune system. In this review, we discuss the contribution of proteomics to these advances, drawing mainly on examples from crop-fungus interactions, from Arabidopsis-bacteria interactions, from elicitor-based model systems and from pathogen studies, to highlight also the important contribution of non-crop systems to advancing crop protection.  相似文献   

5.
Spore coat proteins obtained by extraction with sodium dodecylsulfate/dithiothreitol from six Bacillus spores were compared by immunoblot analysis using antibodies to spore coat proteins from two strains of B. megaterium. Although the extract from spores of each strain had heterogenous proteins with various molecular weights, there were some bands which cross-reacted with specific antibodies from B. megaterium spores. Specific antibody to 48K protein from B. megaterium ATCC 12872 cross-reacted with 17K protein from B. megaterium ATCC 19213, 13K protein from B. cereus and 50K protein from B. subtilis 60015 and B. subtilis NRRL B558. Also, specific antibody to 22K protein from the same strain cross-reacted with 22K and 17K proteins from B. megaterium ATCC 19213 and 13K protein from B. cereus T. Specific antibody to 17K protein from B. megaterium ATCC 19213 reacted with 22K and 19K proteins in addition to 17K protein of own strain, and it was cross-reactive with 16K protein from B. megaterium ATCC 12872, 19K and 27K proteins from B. thiaminolyticus, 13K protein from B. cereus.  相似文献   

6.
用水蒸气蒸馏法结合气相色谱以及气相色谱-质谱联用技术(GC-MS)分析了黑松的健康木和松材线虫危害木中的挥发性物质,并利用触角电位和嗅觉仪测定技术比较分析了松墨天牛对黑松健康木和被害木挥发物的触角电生理和行为反应特点及其对健康木挥发物的日龄变化规律.结果表明,未交配天牛对健康木挥发物的EAG反应值大于被害木,已交配天牛对被害木EAG反应值显著大于健康木;15日龄前的EAG反应值随日龄的增加而升高.在“Y”型嗅觉仪中,未交配天牛对健康木挥发物表现为正趋性,对被害木挥发物表现为负趋性;而已交配天牛对被害木挥发物表现为正趋性,对健康木挥发物表现为负趋性;雌天牛随着日龄的增加对健康木挥发物的正趋性逐渐增强,在15日龄时达到最大,雄天牛在9日龄时正趋性最强.说明不同发育时期的松墨天牛成虫对不同生理状态的黑松具有不同的敏感性和选择性.  相似文献   

7.
A total of 182 Aeromonas hydrophila strains isolated from environmental (food and water) and clinical (stool and other sources) samples taken in mainland Australia, Tasmania and New Zealand were assigned to one of three DNA/DNA hybridization groups (HGs) on the basis of biochemical characteristics, and tested with regard to their ability to produce virulence factors. Strains from HG2 were rarely isolated; strains from HG1 were most commonly isolated from clinical sources; and strains from HG3 formed the majority of environmental strains. There was no correlation of HG to geographic source. Strains from HG2 infrequently produced virulence factors. Strains from HG1 were more likely to produce virulence factors if they came from a clinical source. Overall, strains from mainland Australia produced virulence factors more frequently than those from Tasmania or New Zealand. Strains from HG1 may be of more clinical significance than strains from the other two HGs.  相似文献   

8.
Forty-five fungal isolates from moldy supermarket foods were tested for toxicity to brine shrimp, and twenty-two of these isolates were subsequently tested for toxicity to chicken embryos. Highly toxigenic fungi were Cladosporium sphaerospermum from a bakery product, Fusarium oxysporum from carrots, F. solani from cabbage, Aspergillus niger and Penicillium corylophilum from bread, P. cyclopium and P. herguei from corn meal, P. lanosum from onions,P. steckii from chocolate syrup, Penicillium sp. from jelly, and Rhizopus nigricans isolates from sweet potato, applesauce, and strawberries. Approximately one-third of the fungal cultures were moderately to highly toxigenic to brine shrimp and chicken embryos, while several additional cultures were slightly toxigenic.  相似文献   

9.
利用16对分布于水稻12条染色体上的SSR引物分析78份来自南亚的香稻资源和18份广西种植的香稻的遗传多样性。结果表明:在南亚的香稻资源中,每对引物检测到的等位基因数为3~13个,平均每个位点的等位基因数为5.31个,广西的香稻资源中,每对引物检测到等位基因数2~9个,平均每个位点的等位基因数为3.44个;南亚香稻资源平均多态信息含量(PIC)为0.55,广西香稻资源平均PIC为0.41;南亚香稻资源平均基因多样性(Hs)为0.60,广西香稻资源平均Hs为0.47;说明了南亚香稻资源比广西香稻资源具有更为丰富的遗传多样性。聚类结果表明,大部分的南亚香稻资源或大部分的广西香稻资源各自聚为一类,说明大部分南亚和广西的香稻种质资源存在遗传差异性和地理远缘性。  相似文献   

10.
We developed 15 polymorphic microsatellite loci from the Hawaiian tree Metrosideros polymorpha. These loci were screened against two varieties from several populations and from 23 individuals from one mid-elevation population on Hawaii Island. Loci were variable with the number of alleles per locus ranging from three to 24. Polymorphic information content ranged from 0.222 to 0.941, and observed heterozygosity ranged from 0.261 to 0.955.  相似文献   

11.
Forty-six local and imported wood were tested for resistance to feeding damage by the termite Anacanthotermes ochraceus (Burmeister), the most dominant species in the United Arab Emirates and the Arab Gulf region. Wood was used for construction, wall paneling, and furniture. Wood was evaluated in a 4-wk forced feeding bioassay. Each wood block was graded by the amount of termite damage by using a damage rating index (DRI) of 0 to 5 and wood rating index from very resistant to very susceptible wood. Local wood was mostly susceptible to feeding of termites; imported wood varied in resistance to feeding damage. Wood was placed in groups according to the percentages of weight loss (WL), termite survival (TS), and DRI. Wood was classified as very resistant (%WL from 0.0 to 0.3, %TS from 0.01 to 0.5, and DRI of 0.01), resistant (%WL from 1.1 to 4.9, %TS from 0.8 to 4.8, and DRI of 1.0), moderately resistant (%WL from 6.6 to 9.3, %TS from 6.3 to 8.3, and DRI of 2.0-2.3), slightly resistant (%WL from 10.1 to 19.9, %TS from 9.5 to 28.0, and DRI of 2.5-3.5), susceptible (%WL from 21.5 to 48.6, %TS from 37.3 to 64.8, and DRI of 4.0-4.3) and very susceptible (%WL from 50.0 to 59.8, %TS from 72.8 to 79.0, and DRI of 4.5-5.0). The characterization of the extracts of resistant wood may prove of economic value and lead to the development of new chemicals (repellents or antifeedants) for termite control.  相似文献   

12.
We have determined the sensitivity to 5-azacytidine of cultured fibroblasts obtained from clinically defined areas on the skin of patients with hereditary adenomatosis of the colon and rectum (ACR) and von Recklinghausen neurofibromatosis (NF). Fibroblasts from normal appearing skin of both ACR and NF patients were about 2- to 3-fold more resistant to 5-azacytidine-induced cytotoxicity than were fibroblasts obtained from comparable areas of normal persons. Fibroblasts from café-au-lait lesions and from neurofibromas (NF) were increasingly more resistant to 5-azacytidine than were fibroblasts taken from normal appearing skin of the same NF patients as well as of patients from different pedigrees. The results show that fibroblasts from persons predisposed to cancer and from cancer-prone tissues in such persons are abnormally resistant to 5-azacytidine as determined by the cloning efficiency assay.  相似文献   

13.
The aim of this study was to examine if E. coli isolated from asymptomatic bacteriuria differed in pathogenic features from strains isolated from symptomatic infections of urinary tract. In this study 130 strains of E. coli isolated from women having asymptomatic bacteriuria and 112 strains isolated from patients with symptoms of urinary tract infection were examined. It was shown that E. coli isolated from patients with symptomatic urinary tract infection showed the more frequently ability to cause mannose-resistant haemagglutination of human erythrocytes, resistance to bactericidal activity of serum and haemolytic properties than those isolated from asymptomatic bacteriuria. These strains showed also the higher ability to adhere to Vero cells in tissue culture. Among E. coli strains isolated from persons with asymptomatic bacteriuria the pathogenic features were most frequently found in strains from healthy women and the most rarely in isolated from diabetic women.  相似文献   

14.
By comparing the time of the same distance swum with and without an added resistance, under the assumption of an equal power output in both cases, the drag of 73 top swimmers was estimated. The active drag Fr(a.d.) at maximal swimming velocities varied considerably across strokes and individuals. In the females Fr(a.d.) ranged from 69.78 to 31.16 N in the front-crawl, from 83.04 to 37.78 N in dolphin, from 93.56 to 45.19 N in breaststroke, and from 65.51 to 37.79 N in back-stroke. In the males Fr(a.d.) ranged from 167.11 to 42.23 N in front-crawl, from 156.09 to 46.95 N in dolphin, from 176.87 to 55.61 N in breaststroke, and from 146.28 to 46.36 N in back-stroke. Also, the ratio of Fr(a.d.) to the passive drag Fr(a.d.) as determined for the analogical velocity in a tugging condition (in standard body position-front gliding) shows considerable individual variations. In the female swimmers variations in Fr(a.d.)/Fr(p.d.) ranged from 145.17 to 59.94% in front-crawl, from 192.39 to 85.57% in dolphin, from 298.03 to 124.50% in breaststroke, and from 162.87 to 85.61% in back-stroke. In the male swimmers variations in Fr(a.d.)/Fr(p.d.) ranged from 162.24 to 62.39% in front-crawl, from 191.70 to 70.38% in dolphin, from 295.57 to 102.83% in breaststroke, and from 198.82 to 74.48% in back-stroke. The main reason for such variations is found in the individual features of swimming technique and can be quantitatively estimated with the hydrodynamic force coefficient, which thus provides an adequate index of technique.  相似文献   

15.
Partially purified thymidylate synthetase from Plasmodium berghei and mouse reticulocytes was characterized. The mol. wt of the enzyme from P. berghei was about twice that from mouse reticulocytes. The optimum pH of the enzyme from P. berghei was found to be 6.5-7.5 while that from the host was 7.0-8.0. The enzyme from P. berghei was more susceptible to pH denaturation than the enzyme from reticulocytes. The enzyme from both sources differed in their Km values for substrates. The enzyme from reticulocytes was less sensitive to inhibition by substrate analogs than that from P. berghei.  相似文献   

16.
Bacteriophages isolated from culture supernatants of Pseudomonas syringae pv. syringae and from sewage were identified. The DNA from each phage was isolated and digested with the restriction endonuclease EcoRI. Eight isolates were determined to be different, with two phage isolates from sewage having restriction patterns identical to two phages from culture supernatants. The sizes of the phage DNA ranged from 24 to49 kilobases for isolates from sewage and from 39 to 52.5 kilobases for the isolates from culture supernatants. Buoyant densities of phage particles in CsCl varied from 1.498 to 1.507 g/cm3 for isolates from sewage and from 1.506 to 1.516 g/cm3 for isolates from culture supernatants. Electron microscopy revealed four morphological types. Based on plaque-forming ability of culture supernatants, 31 out of 47 strains of P. syringae are probably lysogenic.  相似文献   

17.
Fibroblasts from skin and skin lesions of patients with tuberous sclerosis (TS) and from skin of normal individuals were grown in culture. ELISA showed that the spent medium of those derived from TS skin lesions contained significantly more fibronectin (FN) than spent medium from the other cells. Amino acid compositional analysis of the FN from TS and normal sources revealed no substantial differences. However the FN of fibroblasts from TS-skin lesions was shown by HPAEC to contain a two- to three-fold increased content of carbohydrate. The changed monosaccharide composition was consistent with an increased content of N- and O-linked glycans and with the former containing polylactosamine chains. Fibroblasts from a normal individual were shown to proliferate more slowly and to produce larger cells when grown on FN from a TS skin lesion compared to growth on FN from normal skin. This revised version was published online in November 2006 with corrections to the Cover Date.  相似文献   

18.
Blood samples were collected from free-ranging elk (Cervus elaphus) harvested in Michigan's northern Lower Peninsula, from moose (Alces alces) relocated from Ontario's Algonquin Provincial Park to Michigan's Upper Peninsula, and from moose from Michigan's Isle Royale National Park. Sera were tested by serum dilution neutralization tests in Vero cell culture for neutralizing antibody to California serogroup viruses, in particular Jamestown Canyon (JC), La Crosse/snowshoe hare (LAC/SSH), and trivittatus (TVT) viruses. Specific neutralizing antibody to JC virus was detected in 71% of 31 and 65% of 20 moose from Algonquin and Isle Royale, respectively. An additional six moose from Algonquin and five from Isle Royale showed evidence of multiple infection. One juvenile moose from Isle Royale had specific neutralizing antibody to TVT virus. Specific neutralizing antibody to JC virus was detected also in 54% of 50 elk from Michigan; 20 of the 50 elk showed evidence of multiple infection. While no single serum sample showed specific neutralizing antibody only to LAC/SSH virus, its presence in sera from some animals may have been masked by the high prevalence of antibody to JC virus.  相似文献   

19.
The feasibility of recirculation of currant-finishing wastewater in a currant-wash process was investigated in a laboratory scale plant. Recycle ratios from 0% to 95% were examined. By increasing the recycle ratio, effluent BOD increased from 681 to 5378 mg/l, effluent COD from 3808 to 43,722 mg/l, total suspended solids from 12.3 to 57.7 g/l, total sugars from 2.57 to 42.13 g/l, total phosphorus from 0.79 to 5.14 mg/l, total Kjeldahl nitrogen from 7.36 to 51.9 mg/l and total phenolic compounds from 0.095 to 1.13 g/l, while fresh water addition decreased from 6 to 0.3 kg/kg of currants processed and total sugars loss from 15.43 to 12.64 g/kg of currants processed. For a recycle ratio of 95%, the mass of currants recovered as a final product increased by 10% due to the proportional decrease in the sugars wasted per kg of currants processed.  相似文献   

20.
Aerosols have been suspected to transport food pathogens and contaminate fruits and vegetables grown in close proximity to concentrated animal feeding operations, but studies are lacking that substantiate such transport. To monitor the potential transport of bacteria originated from fresh or dry manure through aerosols on a dairy, we identified by 16S rRNA sequencing, bacteria in aerosols collected within 2 to 3 meters from dairy cows at two dairies. Gram-positive Firmicutes were predominant in aerosols from a dairy in Sonoma, California, and surrounded by vineyards, in contrast to sequences of Gram-negative Proteobacteria predominant in aerosols from a dairy in Modesto, California, also surrounded by other dairies. Although Firmicutes represented approximately 50% of the 10 most abundant sequences, aerosols from the Sonoma dairy also contained sequences of Bacteriodetes and Actinobacteria, identified previously with animal feces. While none of the top 10 sequences from fresh or dry manure from Modesto dairy were detected in aerosols, two of the sequences from the phylum Bacteriodetes and one from class Clostridia from fresh manure were detected in aerosols from Sonoma. Interestingly, none of the sequences from dry manure were in the top 10 sequences in aerosols from both dairies. The 10 most abundant sequences in aerosols from the Modesto dairy were all from Proteobacteria and nearly half of them were from genus Massilia, which have been isolated previously from immune-compromised people and aerosols. We conclude that the predominant bacteria in aerosols are diverse among locations and that they do not reflect the predominant species of bacteria present in cow feces and/or in close proximity to cows. These results suggest that the aerosol sequences did not originate from manure. Large volumes of aerosols would be required to determine if bacterial sequences from aerosols could be used to track bacteria in manure to crops grown in proximity.  相似文献   

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