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1.
Summary The purpose of this study was to find out whether there existed any difference betweenC. diphtheriae typemitis always present in the nasal cavity of ozaena patients (the so-calledC. belfanti) andC. diphtheriae of themitis type found in diphtheria patients or carriers. Studying in details all the morphological, cultural and biochemical properties, a difference was found to exist in the reduction of nitrates. This test was investigated in 55 strains ofC. belfanti and 45 strains of themitis type ofC. diphtheriae. All the strains ofC. belfanti yielded negative results in the reduction of nitrates, while all strains ofC. diphtheriae typemitis reduced nitrates within 24 hours. The value of this observation was shorty discussed.  相似文献   

2.
Summary Eighty strains ofC. diphtheriae typemitis and 80C. belfanti strains were tested for the rate of rapidity of glucose fermentation according to the method ofParsons andFrobisher. 90% ofC. diphtheriae mitis strains, in contrast to only 13.7% ofC. belfanti strains, fermented glucose in 1 to 2 days. 76% ofC. belfanti strains fermented glucose in 3 to 4 days, whereas some strains needed 8 to 9 days to complete the fermentation. So the results of this test revealed next to that of nitrate reduction, a further difference between the strains ofC. diphtheriae typemitis found in diphtheria and ozaena.  相似文献   

3.
The adaptation ofCamellia rusticana, an evergreen broad-leaved shrub found in areas of heavy snowfall in Japan, to heavy snowfall environments, and the mechanisms by which it is damaged in winter above the snow, were investigated. The stomatal response and photosynthetic characteristics ofC. rusticana were compared to those ofCamellia japonica found in areas of light snowfall. In field conditions, the mean net photosynthesis ofC. rusticana at photon flux density (PFD) over 200 μmol m−2s−1 (Pn(>200). was 50% larger than that ofC. japonica, but in both light saturated and CO2 saturated conditions, the O2 evolution rate (Pc) ofC. rusticana was not different from that ofC. japonica. Mean leaf conductance at PFD over 200 μmol m−2s−1 (gl(>200)) was about 100% larger than that ofC. japonica in the field. The Pn(>200)) was 50% ratio ofC. rusticana was 37% higher than that ofC. japonica which suggests thatC. rusticana's larger Pn(>200) can be explained by its larger gl(>200). WhenC. rusticana trees wintering underneath the snow were projected above it, the leaves of these plants showed serious drought within five days in non-freezing conditions. Their Pc and the maximum stomatal conductance decreased by half and did not recover. The leaves ofC. rusticana showed larger gl(>200) and a less sensitive stomatal response to the decrease of leaf water potential than that ofC. japonica. The stomata characteristics ofC. rusticana caused larger net photosynthesis than that ofC. japonica during the no snow period, and caused the need for snow cover in winter as protector from winter drought.  相似文献   

4.
The solitary endoparasite,Cotesia rubecula, was superior to the gregarious endoparasite,Cotesia glomeratus, in tests of intrinsic competition for their hostArtogeia rapae. When an egg ofC. rubecula was oviposited in the host prior to those ofC. glomeratus, C. rubecula always won the ensuing competition. When an egg ofC. rubecula was laid in the same host within 48 h after oviposition byC. glomeratus, C. rubecula was successful in more than 90% of the interactions. Even when the egg ofC. rubecula was oviposited in the same host 72 to 96 h after oviposition byC. glomeratus, C. rubecula won the competition approximately 33% of the time. The implications of intrinsic competition are discussed in relation to the establishment ofC. rubecula in an ecosystem containingA. rapae andC. glomeratus.   相似文献   

5.
Forty strains ofCandida and one ofTorulopsis were isolated from patients with cutaneous candidiasis. The isolates comprised 29 strains ofC. albicans, 7 strains ofC. tropicalis, 2 strains ofC. guilliermondii, and one each ofC. parakrusei, C. lipolytica, andT. famata were identified by the ordinary method. Besides the common pathogenC. albicans, a few other species ofCandida may be etiologic organisms of cutaneous candidiasis. These strains were re-examined by combined use of sucrose agar slants and slide agglutination tests with IgG monofactorial antibodies as a rapid identification method, especially for determining serotypes ofC. albicans. The new method was useful and reliable for rapid identification ofC. albicans and related species. All strains ofC. albicans isolated from skin lesions proved to be standard serotypes ofC. albicans.
Zusammenfassung Vierzig Stämme vonCandida und eins vonTorulopsis wurden aus Kranken mit kutanen Candidamykosen isoliert. Neunundzwanzig Stämme vonC. albicans, 7 vonC. tropicalis, 2 vonC. guilliermondii, und je einer vonC. parakrusei, C. lipolytica undT. famata wurden mit dem ordinären Methode identifiziert. Außer dem gewohnlichen Erreger,C. albicans, konnten auch ein Paar andere Spezies vonCandida als den Erreger betrachtet werden. Sechsunddreißig Stämme vonC. albicans undC. tropicalis wurden mit der von uns verbesserten kombinierten serologischen und biologischen Methode untersucht, besonders um den Serotypus vonC. albicans festzusetzen. Die neue Methode war gut und zuverlässig als die rapide Identification vonC. albicans und verwandten Spezies. Alle aus der Hautläsion isoliertenC. albicans waren der in Japan allgemeine Serotypus vonC. albicans.
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6.
The effectiveness ofTrichogramma dendrolimi, Trichogramma embryophagum, Trichogramma sp. strain 45 andTrichogramma sp. strain 48 to control the codling mothCydia pomonella L. and the summer fruit tortrix mothAdoxophyes orana F.R. was tested in 4 field trials (1984–1986). Four to sixTrichogramma treatments (depending on the temperature) each at 400 (pillar trees) to 9,000 (round tops) parasites per tree were carried out between June and August to insure the continuous presence ofTrichogramma in the plots. The monitoring was done by examining 3,000 to 10,000 apple fruits per plot. T. dendrolimi reduced the damage ofC. pomonella by 61.35%, ofA. orana by 72.85%.T. embryophagum reduced the damage ofC. pomonella by 50.06%, ofA. orana by 50.8%.Trichogramma strain 45 reduced the damage ofC. pomonella by 41.6% and ofA. orana by 87.9%,Trichogramma strain 48 by 57.2% and 51.2% respectively. The reduction of 67.1% in the number of apple fruits damaged byC. pomonella andA. orana obtained by the inundative releases ofT. dendrolimi in these experiments is considered economically and the use of this species in practice is recommended.   相似文献   

7.
Summary Mycoparasitic behaviour ofCephalosporium roseo-griseum Saksena withAspergillus flavus Link. ex Fries was studiedin vitro. Frequent coiling of hyphae ofC. roseo-griseum around the conidiophores ofA. flavus, penetration of hyphae ofC. roseo-griseum inside those ofA. flavus, and formation of resting bodies byC. roseo-griseum in the conidiophores ofA. flavus were observed.  相似文献   

8.
Synopsis Distribution of leptocephali ofConger in the Western North Atlantic Ocean was studied using specimens from our collections, specimens from other collections, and various existing collection records. The presence of leptocephali ofConger oceanicus andConger triporiceps < 30 mm long over deep water in the southwestern Sargasso Sea in autumn and winter implies a protracted spawning period there. The subtropical convergence zone, meandering east-west across the Sargasso Sea, is probably the northern limit of spawning of both species. Spawning may also occur close to the Bahamas and Antilles.C. triporiceps may spawn also in the Caribbean Sea judging by the capture of small leptocephali in the western Caribbean and of the more southerly continental distribution of its juveniles. The claim of Johannes Schmidt in 1931 that the EuropeanC. conger spawns across the North Atlantic into the western Sargasso Sea is probably incorrect, because leptocephali ofConger are rare in the eastern Sargasso Sea and becauseC. triporiceps, with myomere numbers overlapping those ofC. conger, was recently described in the western North Atlantic. With increasing size, leptocephali ofC. oceanicus and a portion ofC. triporiceps spread westward and northward in the Florida Current and Gulf Stream, but larger leptocephali especially ofC. triporiceps are found also in the Caribbean and Gulf of Mexico. Spawning ofC. oceanicus in the Sargasso Sea indicates that adults cross the Florida Current-Gulf Stream, and successful leptocephali cross the current in the opposite direction to colonize juvenile habitat on the continental shelf, a migratory pattern similar to that of the American eelAnguilla rostrata (Anguillidae).  相似文献   

9.
The effect of the supernatants obtained from the liquid culture medium ofSporothrix schenkii andCandida albicans on the generation of superoxide anion (O 2 and hydroxyl radicals OH., the elements of reactive oxygen species (ROS), and chemilimunescence (CL), a measure of several ROS, by polymorphonuclear leukocytes (PMNs) was examined. In our study, it was shown that the supernatant ofS. schenkii increased all types of ROS generation examined and CL, while that ofC. albicans increased OH. generation and CL. The effect of the supernatants ofS. schenkii on OH. generation and CL and that ofC. albicans on CL were most remarkable when the supernatant obtained 8 weeks after the inoculation was used. The supernatant ofS. schenkii was shown to be a much more potent stimulant than the supernatant ofC. albicans. This ROS-stimulating effect of the supernatant ofS. schenkii was heat stable but not dialyzable. These findings suggest the possible role of ROS produced by infiltrated PMNs in the inflammatory skin lesions induced byS. schenkii.  相似文献   

10.
Sayama  Akira  Kobayashi  Kiroku  Ogoshi  Akira 《Mycoscience》1994,35(1):15-20
Morphological and physiological comparisons were made of sevenHelicobasidium mompa isolates and fourH. purpureum isolates. Colonies of theH. mompa isolates were thin, dense, or hard and dense, and most were pale brown to brown or dark brown, while that of isolate 344c was pinkish. Colonies ofH. purpureum isolates were hard and dense, and their colonies were dark brown. Diameters of hyphae were similar forH. mompa andH. purpureum. Dimensions of conidia and morphology of conidiophores ofH. mompa isolate 344c were close to those ofH. purpureum reported previously.H. mompa isolates grew well at 23°C, 25°C or 27°C, while all isolates ofH. purpureum grew well at 23°C. Growth rates ofH. purpureum isolates was almost the same as those ofH. mompa isolates with slow growth. Polygaracturonase activity at pH 3 was variable among the isolates for bothH. mompa andH. purpureum. Itaconic acid was produced abundantly by three isolates ofH. mompa but not produced by isolate AH130, whereas all isoaltes ofH. purpureum produced a small amount of itaconic acid.  相似文献   

11.
One hundred isolates of 27 species belonging to 13 genera of dematiaceous hyphomycetes were screened for production of cytochalasins C, D and E. Only two isolates ofBipolaris neergaardii and one isolate ofPhoma herbarum produced cytochalasins C and D. Also, cytochalasin E was produced by two isolates ofAlternaria chlamydospora, and one isolate ofCochliobolus tuberculatus. This is the first report about the production of cytochalasins C, D and E by these species of dematiaceous hyphomycetes.  相似文献   

12.
Electrophoretic and morphological variation was studied in 13 cultivars ofC. lanatus and 31 accessions ofC. colocynthis from Israel. Twelve enzyme systems were assayed, representing 19 loci. We found 12 commercially grown cultivars to be monomorphic at all loci. OneC. lanatus accession collected from Israel is highly polymorphic and carries alleles ofC. colocynthis; this accession is probably a representative of a locally cultivated land race grown by Bedouins for animal feed. Over a range of 500 km two forms ofC. colocynthis were identified: one which grows along the coastal plains of the Mediterranean and the other in the arid Negev and Sinal deserts. A high level of electrophoretic and morphological divergence was found between plants of the two regions, whereas within the ecotypes little variation was observed.  相似文献   

13.
The butterfliesPapilio helenus andP. protenor were shown to feed mainly on the nectar of the glory bower,Clerodendron trichotomum, which was the most abundant nectar plant in summer in the study area. Both the species were found to have a proboscis longer than 24 mm corresponding to the length of the corolla tube ofC. trichotomum. Visits to the flowers by these butterflies were observed more frequently than visits by sphingid moths which had previously been believed to be the major pollinators ofC. trichotomum. The male butterflies visited trees ofC. trichotomum frequently, while visits by the females were less frequent. However, once females had visited the tree ofC. trichotomum, they remained there longer than the males. Since the flower ofC. trichotomum has long protruding sexual organs, its pollen grains were found to adhere efficiently to the bodies of butterflies, mainly the thorax, during nectar feeding. Most of the butterflies became loaded withC. trichotomum pollen, and the mean number of pollen grains per butterfly was 1,776 forP. helenus and 2,817 forP. protenor. The flowers opened at any time of day but more frequently in the morning. The nectar was secreted throughout the day. In the maturation of the protandrous flower ofC. trichotomum, the duration of the pistillate phase was about twice as long as the staminate phase. The long flowering period and the short duration of the staminate phase resulted in asynchrony of the flowering stages even within a single cyme on a tree. Such asynchrony and the abundance of attractive flowers on a tree facilitates efficient pollination by the butterflies.  相似文献   

14.
The distribution of two sedge species was studied in two mires which differ in abiotic environments and in distribution ofPhragmites australis. Carex lasiocarpa var.occultans dominated in nutrient-poor valley mire, andCarex thunbergii var.appendiculata dominated in nutrient-rich flood plain subject to water fluctuations.Phragmites australis grew well in nutrient-rich conditions. The distribution ofC. lasiocarpa showed a strong negative correlation withP. australis coverage, whereasC. thunbergii coverage was not affected byP. australis. The leaf area per dry leaf mass (specific leaf area: SLA) ofC. thunbergii increased with shading byP. australis, but that ofC. lasiocarpa was stable. The SLA flexibility ofC. thunbergii to light interception might enable this species to invadeP. australis patches in nutrient-rich environments. The residual nutrient ratio of nitrogen and phosphorus (the ratio of the residual nutrient content at the end of the growing season to peak nutrient content) in the vegetative ramet ofC. thunbergii was 1.7 times higher than that ofC. lasiocarpa. This low residual ratio may indicate effective nutrient recovery to storage organs. The effective nutrient recovery inC. lasiocarpa might enable this species to grow even in nutrient-poor environments. However, it may be difficult forC. lasiocarpa to expand its habitat to nutrient-rich areas whereP. australis dominates as it is not shade tolerant.  相似文献   

15.
Comparative observations of ultrastructure of five species of Candida   总被引:1,自引:0,他引:1  
An electron microscopic comparison was made of five species ofCandida, namely:C. guilliermondii, C. krusei, C. parapsilosis, C. stellatoidea andC. tropicalis. The cell wall, plasma membrane and the cytoplasm with its organelles were described. The cell wall ofC. tropicalis was twice as thick as the cell wall in the other species.C. krusei appeared with distinct, rather elaborate wall sculpturing, a feature not pronounced in the other four species. A single nucleus with nucleolus appeared only in micrographs ofC. guilliermondii andC. krusei. At the same time, large central electron-luscent area (vacuole) appeared in the cells ofC. guilliermondii, C. parapsilosis andC. stellatoidea. The cytoplasm ofC. tropicalis was characterized by a granular appearance. Budding cells and pseudohyphae appeared similar to single cells in their general organelles. Such organelles in species studied were similar to these reported for other yeasts. These include: mitochondria, lipid granules, endoplasmic reticulum, ribosomes and vacuoles.Southwest Foundation for Research and Education, San Antonio, Texas.In partial fulfillment of the requirement of course work for Master of Science, Incarnate Word College, San Antonio.  相似文献   

16.
The proportion ofCandida and non-Candida species in the clinical material from patients. with respiratory-tract diseases was determined.C. albicans was isolated in 102 cases. An additional 89 strains of yeasts, isolated in association with respiratory diseases, belonged to 10 non-albicans Candida spp. andCryptococcus spp. The prevailing species, which occurred in 47 cases, wasC. parapsilosis. C. tropicalis, C. glabrata, andC. guilliermondii were isolated in 12, 10, and 9 cases, respectively. Four strains ofC. krusei and three strains ofC. lusitaniae and one strain each ofC. freyschussii, C. robusta, C. zeylanoides, andCryptococcus neoformans were also isolated.  相似文献   

17.
Dominant phylloplane fungi of guava (Psidium guajava L.) were screened for their antagonistic activities against the two pathogens,Colletotrichum gloeosporioides andPestalotia psidii, bothin vitro andin vivo. Culture filtrates ofAspergillus niger, Fusarium oxysporum andPenicillium citrinum caused more than 50% growth inhibition ofC. gloeosporioides. Filtrates ofCephalosporium roseo-griseum andF. oxysporum were most effective in reducing the growth ofP. psidii. Volatiles produced from the cultures ofA. niger, F. oxysporum, P. citrinum andP. oxalicum inhibited the growth ofC. gloeosporioides, whereas volatiles fromC. roseo-griseum, F. oxysporum andTrichoderma harzianum inhibited the growth ofP. psidii. The inhibitory effect of volatiles decreased with increase in incubation time. In general, the maximum effect of volatiles was noticed after 48 h incubation. Different grades of colony interactions in dual cultures were recognised between the two pathogens and the phylloplane fungi examined. Maximum inhibition ofC. gloeosporioides was caused byAureobasidium pullulans, Cladosporium cladosporioides, epicoccum purpurascens, F. oxysporum andMyrothecium roridum, whereasAspergillus terreus, C. roseo-griseum andP. oxalicum significantly reduced the growth ofP. psidii. Application of a spore suspension of each test fungus inhibited lesion development of guava leaves caused by the test pathogensin vitro. Inhibition was more pronounced when the spore concentration was increased.A. pullulans, C. cladosporioides, E. purpurascens, F. oxysporum, andT. harzianum were found to be strongly antagonistic toC. gloeosporioides. A. niger, A. terreus, C. roseo-grisem andT. harzianum were strongly antagonistic toP. psidii.  相似文献   

18.
A rhizomatous growth form of Codium fragile is described for the first time. Plants were collected in the Gulf of St. Lawrence in estuaries dominated by Zostera marina. Rhizomatous plants developed from propagules of whole plants that settled horizontally. Horizontal axes of C. fragile were up to 1 m long in plants collected in situ. Plants developed several to dozens of erect axes at right angle to the base. Horizontal growth of up to 0.2 m was found in field experiments where fragments were tied to plastic mesh and left in situ for 4 months. The unconsolidated filaments at the base of C. fragile often wrapped around the rhizomes of Z. marina and up to five separate attachment sites to eelgrass were found in single plants of C. fragile. In four estuaries, 57–100% of Codium plants with identifiable substratum were attached to shoots and rhizomes of Z. marina. The rhizomatous growth form was found in plants identified as C. fragile ssp. tomentosoides (Nova Scotia and Prince Edward Island) and C. fragile ssp. atlanticum (Prince Edward Island), suggesting that this is a phenotypic response to growth in soft bottom environments.Communicated by K Lüning  相似文献   

19.
The results ofin situ cross-hybridization of the cloned DNA fragments of BRa, BRb and BRc fromChironomus thummi to the polytene chromosomes of 14Chironomus species andCamptochironomus tentans are presented. BRs of the species studied were demonstrated to contain the homologus DNA sequences. The cloned fragment from the BRa ofC. thummi hybridized with the BRa ofC. piger and with a region on the arm G ofC. tentans andC. plumosus, the latter species had no extra BR. The clone 16 from the BRb ofC. thummi hybridized only with the developed BR on the arm G of all species studied. The sequence from the BRc ofC. thummi was located in the BRc ofC. piger and in the developed BR ofC. plumosus andC. nuditarsis, which were located at the most distal end of arm G. These clones can be used as markers of homologous BRs. The new mobile elements C6.10 fromC. thummi genome were localized on the polytene chromosomes of 10Chironomus species andCamptochironomus tentans. The species of the generaLipiniella, Cryptochironomus andGlyptotendipes did not contain the sequences homologous to ME C6.10.  相似文献   

20.
As part of a larger investigation of theC. alpinum-C. arcticum complex of arctic and North Atlantic areas, isozyme variation ofC. alpinum, C. arcticum, and related taxa was analysed. A total of 124 multilocus phenotypes was divided into more or less distinct groups by numerical analyses. Most groups correspond well to previously recognized taxa. However, what has traditionally been considered asC. arcticum was divided into two distinct groups, consisting of northern (Svalbard, Greenland) and more southern (Norway, Iceland) populations, respectively. The division ofC. arcticum into two taxa is also supported by other kinds of data and the two taxa probably deserve species rank. Serpentine plants from Shetland had multilocus phenotypes similar to those ofC. arcticum from Iceland and should be included in the southern taxon.  相似文献   

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