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1.
L A Grigor'eva 《Parazitologiia》1992,26(5):430-435
In order to estimate the absolute number of Stomoxys calcitrans subpopulation in housings of a dairy farm the capture-mark-recapture method has been used. It has been established that the absolute number of S. calcitrans subpopulation can be as high as 100,000 specimens per a farmyard. The possibilities of using indices of the relative number of flies (caught on fly-paper) for estimation of the absolute number of these insects in the housings of farms have been found out. 相似文献
2.
Z Janczewski L Bablok S Fracki A Smith 《Polski tygodnik lekarski (Warsaw, Poland : 1960)》1992,47(24-26):530-532
A structure of the convoluted tubuli, spermatogenesis and number of Leydig's cells in the andropause have been analysed in dependence on the degree of symptoms intensity. A control group included otherwise healthy men with ++post-inflammatory azoospermia. A percentage of the convoluted tubuli with normal tissue (p < .002) and spermatogenesis (p < .001) has been significantly decreased in andropause. The number of Leydig's cells has not differed in andropause and in a control group (p < .05). No difference of significance have been noted in the structure of convoluted tubuli, spermatogenesis, and Leydig's cells number depending on the intensity of symptoms. FSH and LH levels have been significantly increased in andropause (p < .001). No relationship between FSH and LH levels and percentage of the abnormal convoluted tubuli has been observed. However there have been a relationship between FSH and LH levels and the number of abnormal convoluted tubuli with spermatogenesis inhibition and intensified clinical symptoms. There has also been a relationship between FSH and LH levels and Leydig's cells number in patients with marked symptoms of andropause. 相似文献
3.
R I Valitskaia G S Shishkin T V Voevoda 《Biulleten' eksperimental'no? biologii i meditsiny》1988,106(7):122-124
The structure of the bronchial tree in the lung lobules has been studied and the number of lobules and acini in different lobes and in the entire lung has been determined in polar foxes and dogs. Branching pattern and the number of generations of interlobular and intralobular bronchioli have been defined. It has been found that the number of lung lobules in polar foxes was twice as high as in dogs, the lobule volume being smaller almost by half. A smaller number of acini in polar fox lobules enables the central regulation mechanisms to intensify the control of local ventilation. It broadens the possibilities for physiological responses to the influence of climatic factors of the Extreme North. 相似文献
4.
C R Triggle 《Canadian journal of physiology and pharmacology》1985,63(4):353-354
The etiology of essential hypertension has been under intensive investigation for a number of years, and the availability of a number of rat models of this disease has aided our understanding of the relationship between abnormalities in cardiovascular regulatory function and hypertension. It is accepted that abnormalities at a number of levels of these regulatory processes could be the basis of the pathological process; however, the cause-effect relationship has not always been clearly established. This introduction addresses the potential relationship between a number of parameters and the control of blood pressure, and the Symposium attempts to relate altered smooth muscle and membrane function to hypertension. 相似文献
5.
L A Piruzian E M Mikha?lovski? V A Dement'ev 《Izvestiia Akademii nauk SSSR. Seriia biologicheskaia》1989,(6):838-842
On the basis of analysis of a number of documents concerning the molecular mechanisms of actions of well-known drugs the first attempt has been made to subdivide their activities into traditional and nontraditional ones. The possibility of application of a number of well-known drugs to nontraditional fields of pharmacology has been demonstrated. 相似文献
6.
The applicability of the Wittig-Horner reaction to a number of ketosteroids has been studied. A number of regularities have been shown to exist. 相似文献
7.
Site-directed mutagenesis reveals the importance of conserved charged residues for the transport activity of the PheP permease of Escherichia coli. 总被引:2,自引:2,他引:0
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Site-directed mutagenesis has been used to identify a number of charged residues essential for the transport activity of the PheP protein. These residues are highly conserved in the cluster of amino acid transporters. However, some other conserved residues and a number of aromatic residues have been shown not to be essential for transport activity. 相似文献
8.
《Journal of bryology》2013,35(2):233-258
AbstractTwenty-eight moss species have been investigated cytologically. Mitotic karyograms have been presented for most of these species and these show a remarkable similarity in the n = 11 karyotype. Nine of the eleven chromosomes have terminal or sub-terminal centromeres. Lightly staining heterochromatic bands frequently occur along the axis of the chromosomes and very often these are the sites of chromosome bending; it has been suggested that these may be areas of neocentric activity. The karyotypes investigated show a reduction series of chromosome number which is paralleled by an increase in the number of long metacentrics; since the number of major chromosome arms is maintained in most of the species it has been suggested that Robertsonian fusion has been an important mechanism in the evolution of the Bracytheciaceae, and probably in all Diplolepidous mosses. Polyploidy has also played an important role in speciation. Finally it has been proposed that n = 11 is the primary basic number in the Diplolepideae. 相似文献
9.
I E Semina N V Tsvetkova M M Garaev 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》1982,(7):65-69
A number of physico-chemical properties of Bordetella pertussis DNA has been studied. The values of its floating density and melting point have been established, which has allowed one to calculate the GC composition of B. pertussis DNA. The average molecular weights of the fragments of B. pertussis DNA, resulting from its hydrolysis with specific endonucleases EcoR, BamH 1, Sal 1, Pst 1, have been determined, and thus the basis has been provided for establishing the number of clones necessary for obtaining the complete lset of B. pertussis genes. 相似文献
10.
Derivation of unstirred-layer transport number equations from the Nernst-Planck flux equations.
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P H Barry 《Biophysical journal》1998,74(6):2903-2905
Since the late 1960s it has been known that the passage of current across a membrane can give rise to local changes in salt concentration in unstirred layers or regions adjacent to that membrane, which in turn give rise to the development of slow transient diffusion potentials and osmotic flows across those membranes. These effects have been successfully explained in terms of transport number discontinuities at the membrane-solution interface, the transport number of an ion reflecting the proportion of current carried by that ion. Using the standard definitions for transport numbers and the regular diffusion equations, these polarization or transport number effects have been analyzed and modeled in a number of papers. Recently, the validity of these equations has been questioned. This paper has demonstrated that, by going back to the Nernst-Planck flux equations, exactly the same resultant equations can be derived and therefore that the equations derived directly from the transport number definitions and standard diffusion equations are indeed valid. 相似文献
11.
M. V. Astakhov 《Inland Water Biology》2014,7(1):48-55
Diurnal dynamics of invertebrate drift in the Kedrovaya River (Primorsky Krai, Russia), which flows in the zone of influence of the monsoon climate, has been studied. It has been shown that drifting invertebrates tend to shift from a predominantly daytime drift pattern to a distinguished nocturnal drift pattern during the frost-free period. The ratio of the total number of nighttime migrants to the total number of daytime migrants increased with every subsequent month. It has been proposed that the degree of light contrast between day and night can be significant in the regulation of nocturnal drift intensity. 相似文献
12.
13.
Eugene N. Kozloff 《The Journal of eukaryotic microbiology》1957,4(2):75-79
SUMMARY. A ciliate found in the renal organ of the gray garden slug, Deroceras reticulatum , is referred to Tetrahymena (Paraglaucoma) rostrata (Kahl). In the parasitic phase, the ciliate is evidently not histiophagic. It is readily cultivated in bacterized tissue infusions, and has been established in axenic culture in yeast extract.
The number of complete primary ciliary meridians in ciliates of the parasitic phase has been observed to range from 41 to 58; in ciliates from cultures, the number of meridians has been observed to range from 28 to 37. In culture, the form of T. rostrata from D. reticulatum appears to be morphologically identical with a strain (NZ-4) recovered from soil in New Zealand. 相似文献
The number of complete primary ciliary meridians in ciliates of the parasitic phase has been observed to range from 41 to 58; in ciliates from cultures, the number of meridians has been observed to range from 28 to 37. In culture, the form of T. rostrata from D. reticulatum appears to be morphologically identical with a strain (NZ-4) recovered from soil in New Zealand. 相似文献
14.
Christopher H Evans Steven C Ghivizzani Paul D Robbins 《Arthritis research & therapy》2009,11(1):209-12
During the decade since the launch of Arthritis Research, the application of gene therapy to the rheumatic diseases has experienced the same vicissitudes as the field of gene therapy as a whole. There have been conceptual and technological advances and an increase in the number of clinical trials. However, funding has been unreliable and a small number of high-profile deaths in human trials, including one in an arthritis gene therapy trial, have provided ammunition to skeptics. Nevertheless, steady progress has been made in a number of applications, including rheumatoid arthritis and osteoarthritis, Sjögren syndrome, and lupus. Clinical trials in rheumatoid arthritis have progressed to phase II and have provided the first glimpses of possible efficacy. Two phase I protocols for osteoarthritis are under way. Proof of principle has been demonstrated in animal models of Sjögren syndrome and lupus. For certain indications, the major technological barriers to the development of genetic therapies seem to have been largely overcome. The translational research necessary to turn these advances into effective genetic medicines requires sustained funding and continuity of effort. 相似文献
15.
The mast cell population has been studied during early decidualization of the mouse uterus. The number increases in early pregnancy until the attachment phase when a sharp depletion is noticed. This fall has been correlated with stimuli of maternal origin, but at the same time the presence of a blastocyst at the presumptive implantation sites seems to exert a significant effect on the depletion of mast cells. A relationship between the number of mast cells in the uterus and the physiological state of the organ has definitely been established [Harvey, 1964; Likar and Likar, 1964; Gibbons and Chang, 1972; Brandon and Evans, 1983]. The number of mast cells in the pregnant uterus is known to decrease around the time of implantation in the rat [Shelesnyak, 1960; De Feo, 1967; Brandon and Bibby, 1979]. Several workers believe that the mast cell population and histamine content decrease as a result of a rise in circulating estrogen [Westin, 1955; Gibbons and Chang, 1972; Spaziani, 1975]. In the present communication the possibility of a relationship between the decrease in mast cell population and the presence of a blastocyst, whose estrogenic role has been reported [Dickmann and Dey, 1973; Dickmann et al., 1975; Sengupta et al., 1977], in the uterine horn has been discussed. 相似文献
16.
DNA coding for the 18S and 25S rRNAs in flax (Linum usitatissimum) has been purified and is arranged in tandem arrays with a repeat length of 8.6 kb. There is no detectable variation in the size of this repeat unit. Single repeat units have been cloned in the plasmid pAT 153. The coding sequences for the 25S, 18s and 5.85 rRNAs have been localised by hybridisation. The cloned rDNA has been used to compare two genotrophs, L1 ad S1, where the number of rRNA cistrons has been altered by growth under different environmental conditions. In terms of the size of the repeat unit and the position of a number of restriction enzyme sites the rDNAs from L1 and S1 were identical. 相似文献
17.
Food comminution during chewing is the composite result of selection and breakage. In the selection process, every food particle has a chance of being placed between the antagonistic post-canine teeth and being subjected to subsequent breakage. The selection chance, being the ratio between the number of selected and offered particles, has been mathematically described as a function of the number of particles offered, in terms of the number of breakage sites available on the teeth and particle affinity, i.e. the fraction of breakage sites occupied by one particle. The assumption has been made that particles are successively selected during a jaw-closing phase and that the selection chance of subsequent particles having the opportunity to occupy a breakage site proportionally decreases with the unoccupied fraction of the breakage sites left. The number of selected particles of a single size then asymptotically approaches the total number of breakage sites available for that size, when the number of particles offered increases. The critical particle number, derived from the measure of particle affinity, indicates the number of particles by which the breakage sites become saturated. The selection model for single particle sizes has been successfully applied to describe one-chew experiments, using various numbers and sizes of particles made of a silicone-rubber. After pseudo-chewing movements the subjects were unexpectedly instructed to carry out a real chew on particles (half-cubes). Undamaged, hence non-selected half-cubes could afterwards be distinguished from broken particles. The model has been extended to a particle mixture to describe the selection of particles of a certain size while other particles of different sizes are present. If a two-way competition between smaller and larger particles is assumed, the model predicts that the ratios of the selection chances between different particle sizes do not depend upon the numbers of the particles in the mixture. 相似文献
18.
Eric H. Roalson 《The Botanical review》2008,74(2):209-393
The Cyperaceae are well known for having a large amount of variation in chromosome numbers both within and among genera. Most
of this variation has been previously attributed to agmatoploid or qualitative aneuploid chromosome number change. To date
there have been 4,231 reported chromosome number counts in the family. Despite the large number of counts made, they only
represent approximately 16% of the species currently recognized. These counts are here presented in an indexed list with standardized
nomenclature following a draft copy of the World Checklist of Cyperaceae. Additionally, I explore variation within genera
where a significant number of counts have been made. Given the distributions of counts within genera there is evidence for
both agmatoploid and polyploid chromosome number changes. 相似文献
19.
The growth of drug addiction has been noted in Nikolaev. This growth has not been stopped by methods based on the use of force. The results of work in accordance with the program "Harm Reduction" are presented. The program functions on the basis of the Charity Fund "Blahodiinist" and is intended for the prevention of the spread of HIV infection in groups of risk among injecting drug users and in other groups. The realization of the program includes provision of information material, reduction of harm in connection with the use of drugs by injection and the risk of getting HIV and sexually transmitted diseases. The analysis of the results has shown the effectiveness of the program (the frequency of using condoms has increased, the number of sex partners and the number of casual liaisons have dropped, the custom of using sterile syringes has been formed). Considering that during epidemics the coverage of not less than 70% of the representative of risk groups is necessary, the program should be realized on a greater scale to increase its effectiveness. 相似文献
20.
Updating the H-antigen classification of Bacillus thuringiensis 总被引:5,自引:0,他引:5
Lecadet MM Frachon E Dumanoir VC Ripouteau H Hamon S Laurent P Thiéry I 《Journal of applied microbiology》1999,86(4):660-672
The classification of Bacillus thuringiensis strains has been revised and updated based on flagellar antigens which have been in use for many years. Sixty-nine serotypes and 13 sub-antigenic groups have now been identified, giving 82 serovars among the 3500 B. thuringiensis isolates of the IEBC Collection. The number of serovars has gradually increased with the total number of strains. The biochemical characters used have also been investigated and their value assessed for identification of B. thuringiensis at the subspecies level. A crystal analysis was carried out in terms of morphology, delta-endotoxin profiles and larvicidal activity for the newly identified serovars. It was found that atypical crystals, some with novel components, are becoming more common. No insect susceptible to these serovars has been discovered among known target species. The number of cross-reacting H-antigens among B. cereus strains is increasing and may be of biological significance. 相似文献