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231.
ABSTRACT Spiroplasma citri, transmitted by phloem-feeding leafhoppers, moves from the gut lumen through the gut wall, hemolymph, and salivary glands and multiplies in insect tissues. Nontransmissible lines were deficient in their ability to cross these barriers. Molecular analysis revealed extensive chromosomal rearrangements between the transmissible and nontransmissible spiroplasma lines including a large chromosomal inversion and deletions of about 10 kb at each inversion border. One open reading frame of the deleted region, cloned from the transmissible strain BR3-3X, encodes an integral membrane protein of 58 kDa that shares limited sequence similarity with major adhesin proteins of two zoopathogenic mycoplasmas. Adhesion of spiroplasmas to cultured leafhopper cells was inhibited by proteases, suggesting that adherence to host cells is mediated by spiroplasma membrane protein(s). A hypothetical model for insect transmission of phytopathogenic mollicutes is presented. 相似文献
232.
F. Tanno U. Weber Ch. Wacker L. Gaschen V. Schmid J. Lang 《The Journal of small animal practice》1998,39(9):432-436
Ultrasonography was used to compare adhesions induced by two different methods of gastropexy in 16 dogs. An incisional gastropexy technique was used in eight dogs (group 1) and a 'modified' gastropexy technique in the remaining eight (group 2). The length and thickness of the gastropexy and the peristaltic activity of the stomach were measured ultrasonographically and compared between groups. Measurements for the two groups were taken in the early postoperative interval (two to four days), intermediate postoperative interval (eight to 20 days) and late postoperative interval (57 to 79 days). Both techniques were equally successful in forming permanent adhesions at two months postoperatively and there was no recurrence of gastric dilatation and volvulus. The length and thickness of the gastropexy were similar for both groups at two months postoperatively and there were no surgical complications with either technique. The modified gastropexy provides a technique that can easily be performed by a single surgeon , with no increased operative time or duration of anaesthesia, and with the formation of a permanent adhesion. 相似文献
233.
Potter Deborah U. Gosz James R. Molles Manuel C. Scuderi Louis A. 《Landscape Ecology》1998,13(4):203-214
Landscape Ecology - We investigated the question “Is there a relationship between seasonality in precipitation and vegetative cover in Pole Canyon, NM?” GIS and statistical methods were... 相似文献
234.
S. P. MATHUR A. BELANGER†† S. U. KHAN‡‡ H. A. HAMILTON†† R. GREENHALGH‡‡ K. A. MACMILLAN†† 《Weed Research》1976,16(3):183-189
In a field experiment on an organic soil, a pre-emergence application of paraquat at 2–24 kg a.i. (active ingredient)/ha was made to a plot on which onions and lettuce were grown; and similar broadcast applications of linuron, both with and without carbofuran, at two field rates, to plots on which carrots were grown. Paraquat generally increased the bacterial and actinomycetal populations while linuron inhibited the same but enhanced the numbers of fungal propagules, although it decreased the proportion of soil penicillia in the population. The overall effect of linuron was not changed by the admixture of carbofuran. However, the changes in microbial populations by either herbicides were not substantial enough to make gross or lasting differences in levels of available N and P, and in the CO2 evolution rate. 相似文献
235.
The isolation and NMR spectra of otosenine (1) and seneciphylline (2) from Senecio lorenthii are reported. 相似文献
236.
237.
Acute disseminated intravascular coagulation (DIC) was diagnosed in a 3 1/2 year old cow of the Simmental breed. The cow was little less than 6 months pregnant and was admitted to the clinic because of severely disturbed general health. The most important clinical findings were increased heart and breathing rate, rectal temperature of 39.9 degrees C, nosebleed and petechiae on the nasal mucosa. Additionally, the cow showed petechiae on the vaginal mucosa, haemorrhage from the rectum lasting several hours after rectal examination and severe haemoglobinuria. Haematological and biochemical examinations showed increased liver enzymes and severe changes in all coagulation parameters (platelet count, PT, PTT, thrombin time, fibrinogen, fibrin degradation products). Based on the mentioned findings the diagnosis DIC was made. Possible causes were severe necrotic endometritis and placentitis combined with fetal death. High counts of Escherichia coli and Clostridium perfringens were determined in liver, lung and abomasal contents of the aborted fetus as well as in the placenta. Uterine secretion contained Actinomyces pyogenes besides. 相似文献
238.
239.
O. Schmidt D. Dujesiefken H. Stobbe U. Moreth R. Kehr Th. Schröder 《Forest Pathology》2008,38(2):124-128
Bacteria were isolated from necrotic lesions on a horse chestnut tree (Aesculus hippocastanum) with bleeding canker in Hamburg, Germany. Sequencing of the rDNA-ITS region revealed great similarity to pathovars of Pseudomonas syringae. Pseudomonas syringae pv. aesculi was identified by sequence homology of the gyrase B gene. This is the first report of P. syringae pv. aesculi in Germany. Phytophthora was not detected. 相似文献
240.
Cats vaccinated against FPLV were protected against infection with a feline isolate of CPV2b. Nonvaccinated cats developed a lymphopenia and excreted virus which infected susceptible in-contact cats. 相似文献