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401.
O Iu Filimonova S A Grudinina S V Sidorenko L K Katosova M A Fatova L G Stoliarova N V Dubrovskaia 《Antibiotiki i khimioterapii͡a》2004,49(12):14-20
The results of 3-year observation on emergence of H. influenzae antibiotic resistant strains in Moscow are summarized. The study included 566 strains isolated from patients in 2002-2004. The susceptibility was determined by the 2-fold microdilution method on the Haemophilus test medium. The percentage of the resistant strains isolated in 2002, 2003 and 2004 was the following: ampicillin --4.9, 3.2 and 3.6%, tetracycline--3.3, 3.2 and 1.8% and co-trimoxazole--10.9, 20.9 and 20% respectively. The strains isolated in 2003 and 2004 were resistant to azithromycin in 0.6 and 1.8% of the isolates and to clarithromycin in 1.3 and 3.2% of the isolates respectively. Five isolates differed by the minimum resistance to ampicillin whereas producing no beta-lactamase (BLNAR strains). The drugs of choice for the treatment of respiratory tract infections mainly due to H. influenzae, i.e. acute otitis and sinusitis, chronic bronchitis exacerbation and sometimes pneumonia remain betalactam antibiotics. From the microbiological viewpoint the inhibitor-protected aminopenicillins, cefuroxime and cefotaxime have no significant advantages vs. amoxycillin. The use of cotrimoxazole and chloramphenicol should be considered inexpedient. 相似文献
402.
The apyrene paraspermatogenesis in the freshwater gastropod
Pomaceacanaliculata has been studied with electron
microscopy. Matureapyrene parasperm result from a cytodifferentiation
processwithout maturation division. The atypical condition is
recognizedearly. Paraspermatogonia are characterized by voluminous
nucleiwith irregular clusters of heterochromatin, numerous dilated
cisternaeof the rough endoplasmic reticulum and small electron-dense
granulesspread through the cytoplasm. As this process advances, the
nucleibecome lobed and chromatin degenerates. The remnant chromatin
condensesto form dense bodies which are finally excreted from the
cells.At the cytoplasmic level a centriolar multiplication with the
consequentflagellogenesis takes place. The axonemal microtubules run
alongthe entire length of the cell and emerge from the posteriorend
forming a tuft of three or more free flagella. The roughendoplasmic
reticulum and the Golgi complex are involved inthe production of
secretory granules, some of which are laterreleased by exocytosis. At
the end of paraspermatogenesis matureapyrene parasperm are
fusiform-shaped anuclear ciliated cells. (Received 20 January 2000; accepted 18 July 2000) 相似文献
403.
Problem of three-dimensional structure of chromatin is reviewed. Data concerning ranged distribution of chromosomes in nucleoplasm are shown. Special attention being paid to the role of nuclear matrix in maintenance of nucleus topology. Possible role of satellite sequences and DNA-binding proteins is discussed. 相似文献
404.
In temperate climates, Pustula tragopogonis is rarely found on cultivated sunflower. In Europe, it was so far of little economic impact on other Asteraceae, except for some regions in the Mediterranean. In 2003, P. tragopogonis was found for the first time in sunflower fields in southern Germany. The pathogen has a widespread occurrence there, especially in the region around Stuttgart, BW. Fatty acid profiling, ultrastructural investigation and ITS sequencing revealed a high similarity to an 2002 isolate from southern Africa and an 2005 isolate from Australia, but revealed significant differences to P. tragopogonis s.l. on Cirsium arvense, a common weed, growing on or in the vicinity of sunflower fields in Germany. P. tragopogonis from this host can therefore be excluded from being the source of the reported infection. 相似文献
405.
Beavers Castor spp. are generalist herbivores, feeding on the bark, shoots and leaves of woody plants, terrestrial herbs and forbs, ferns and aquatic vegetation. As central-place foragers, beavers move out from water to select and cut trees and vegetation, and then transport it back to their refuge. These terrestrial forays are energetically costly; therefore, beavers should concentrate their foraging activity near the central place and increase the degree of selectivity for specific sizes or species of food with increasing distance from the water. The aim of this study was to test the predictions of the central place and the optimal foraging theories for the food selection of the Eurasian beaver Castor fiber , and show the foraging preferences of the focal species in the boreal conifer forest zone of Europe. Foraging intensity by beavers and the abundance of woody species were surveyed in transects positioned randomly at seven beaver territories. In compliance with the central-place foraging theory, the foraging intensity declined with increasing distance from the river. Beavers fed preferentially on willows ( Salix ), rowan ( Sorbus ) and birches ( Betula ), although alders ( Alnus ) dominated their diet. Size selectivity showed similar patterns to previous North American studies, which were also carried out in habitats with predominantly small saplings. The probability of selection of small saplings dropped as distance increased, which is consistent with the predictions of optimal foraging models that larger prey items are more likely to be favoured with increasing provisioning distance. 相似文献
406.
Atp-activated ionic permeability in smooth muscle cells isolated from the guinea pig urinary bladder
Smooth muscle cells from the guinea pig urinary bladder were investigated by voltage clamping at the plasma membrane and using an intracellular perfusion technique. Applying adenosine triphosphate (ATP) at a concentration greater than 3 × 10–8 M and at a membrane potential of –100 to –30 mV produced a rise in fast inward transmembrane current. A similar effect was exerted by adenosine diphosphate (ADP) and -, -, and ,-methylene ATP. Application of guanosine triphosphate, inosine triphosphate, adenosine monophosphate (AMP), and adenosine failed to activate this current. It was found that AMP blocks ATP receptors competitively. No pharmacological differences were found between the latter ATP receptors and those of rat sensory neurons. The ATP receptors were rapidly desensitized and recovered their sensitivity to agonists extremely slowly. Speed of desensitization was reduced by a decrease in ATP concentration.A. A. Bogomolets Institute of Physiology, Academy of Sciences of the Ukrainian SSR, Kiev. Translated from Neirofiziologiya, Vol. 19, No. 1, pp. 95–100, January–February, 1987. 相似文献
407.
Monosynaptic pathway responsible for generation of bursting activity in theHelix pomatia RPal neuron
The connection between a visceral ganglia interneuron initiating bursting pacemaker activity in the RPal neuron and the RPal neuron itself was investigated inHelix pomatia. Stimulating the interneuron either initiated or intensified bursting activity in the RPal neuron, depending on initial electrical activity in this cell. Replacing calcium with magnesium ions in the extracellular fluid and adding CdCl2 to this fluid reversibly inhibited the effect of interneuronal stimulation on the RPal neuron. The latter effect was unaffected by increasing the concentration of extracellular Ca2+ 10 to 70 mM. Intracellular injection of both Cs+ and TEA into the interneuron produced an increase in the duration of its action potentials and rendered the link connecting the neurons more effective. It is deduced that a monosynaptic chemical connection exists between the interneuron and the RPal neuron for which a peptide compound serves as transmitter.A. A. Bogomolets Institute of Physiology, Academy of Sciences of the Ukrainian SSR, Kiev. Translated from Neirofiziologiya, Vol. 19, No. 1, pp. 20–28, January–February, 1987. 相似文献
408.
409.
The antiaggregatory effects of 6-oxo-PGE1 were evaluated in vivo in the rat using a minimally invasive technique involving 111-Indium labelling of platelets. The antiaggregatory effects on adenosine diphosphate-induced aggregation were compared with those of prostacyclin (PGI2) and prostaglandin E1 (PGE1) following slow infusions and bolus injections. The rank order of antiaggregatory potency was PGI2 greater than 6-oxo-PGE1 greater than PGE1 while the rank order of duration of antiaggregatory effects was PGE1 greater than 6-oxo-PGE1 greater than PGI2. The kinetics of the antiaggregatory effects of these prostaglandins suggests that such actions are not mediated by direct effects on platelets, but through a secondary mechanism. 相似文献
410.
Dr. M. P. Pistillo N. Tanigaki O. Mazzoleni E. Ciccone U. Hämmerling M. Park P I. Terasaki G. B. Ferrara 《Immunogenetics》1987,25(3):145-151
Peripheral B lymphocytes obtained from three healthy individuals who had been immunized against peripheral blood lymphocytes from appropriate HLA-incompatible donors were transformed by the use of Epstein-Barr virus. The transformed blastoid B cells were repeatedly subcultured by means of cluster picking, and the HLA antibody-producing cultures were identified by testing the culture supernatants by means of the cytotoxicity assay, using the corresponding donor cells. Thus far, four cell lines that secrete cytotoxic HLA antibodies (MP1, 3, 4, and 5) have been established. Specific immunoabsorption experiments revealed that the antibody activity is carried by lambda-type IgM for MP1, by kappa-type IgM for MP3 and MP5, and by both for MP4. Specificity analysis of a panel of HLA-pretyped cells indicated that MP1 detects DQw2, whereas MP5 recognizes B7. The specificity of MP3 was similar to a DQ specificity termed DC5 (probably equivalent to TA10) but not the same. In the case of MP4, both of the lambda-type and kappa-type antibodies appeared to be directed toward new HLA class 11 determinants.Abbreviations used in this paper HLA
human major histocompatibility
- EBV
Epstein-Barr virus
- B-LCL
Blymphoblastoid cell line
- NA
not absorbed
- PBS
phosphate-buffered saline
- SPA
Sepharose protein A
- NRS
normal rabbit serum 相似文献