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1.
The dynamics of proliferative activity of cells was studied in the cultures of organotypic recombinants obtained from embryonic lung epithelium (E) and mesenchyma (M) of the intact and treated transplacentally by urethane mice (strain A). The labelling index (LI) of E and M in the aggregates obtained from treated embryonic lungs (EtMt) was significantly higher than LI in the aggregates from intact embryonic lungs (EiMi) in all days of cultivation (4-7-14). M from the treated embryonic lungs stimulated LI of the intact E (EiMt) but M from the intact embryonic lungs decreased LI of the treated E (EtMi).  相似文献   

2.
Cross-immunoreactivity of juvenile hormone esterase (JHE) from different species was tested using anti-JHE (Trichoplusia ni) (Noctuidae) polyclonal antibody. Partial cross-reactivity was observed between JHE from Hyphantria cunea, Isia isabella (Arctuidae) and Spodoptera exigua (Noctuidae) in immunoblot analysis. Soluble antigen-antibody complex formation was observed between anti-JHE (T. ni) and antigen(s) from Heliothis virescens (Noctuidae) during immunotitration of antigen(s). Using an ELISA method the highest cross-reactivity was observed for both species from Arctuidae and lower cross-reactivity for antigen(s) from H. virescens.  相似文献   

3.
Four new species of the nasal mite family Rhinonyssidae collected in different regions of the former USSR are described: Neonyssus (Otocorinyssus) alaudae sp. n. from Alauda arvensis L. (Alaudidae, Passeriformes) from Turkmenistan; Rhinonyssus clangulae sp. n. from Clangula hyemalis (L.) (Anatidae, Anseriformes) from Yakutia; R. marilae sp. n. from Aythya marilae L. (Anatidae, Anseriformes) from the Russian Far East; Locustellonyssus sibiricus sp. n. from Locustella certhiola (Pall.) (Sylviidae, Passeriformes) from Siberia.  相似文献   

4.
The objective was to determine the in vitro developmental competence of buffalo oocytes collected from abattoir-derived ovaries at various stages of the estrous cycle and follicular status. In Experiment 1, ovaries (n=476 pairs) were collected and divided into the following five groups: (a) ovaries with a corpus hemorragicum and no dominant follicle (CH-NO-DF); (b) ovaries with a mature functional corpus luteum (CL) and a dominant follicle (CL-DF); (c) ovaries with a mature functional CL and no dominant follicle (CL-NO-DF); (d) ovaries with a regressing CL and a dominant follicle (RCL-DF); and (e) ovaries without any luteal structures and only small follicles (ANEST). In Experiment 2, 144 pairs of ovaries with a CL (or regressing CL) and a dominant follicle were collected and follicles were classified as dominant, largest subordinate, and subordinate. In both experiments, the dominant follicle was defined as any follicle >10mm in diameter that exceeded the diameter of all other (subordinate) follicles. Although oocytes were collected from each group of ovaries, only Grades A or B oocytes were used for in vitro embryo production. Cleavage rates were higher (P<0.05) from oocytes collected from ovaries in the CH-NO-DF (59.6%) and CL-NO-DF (59.2%) groups than those collected from CL-DF (52.2%) and ANEST (43.6%) groups. The yield of transferable embryos was higher (P<0.05) from oocytes collected from CH-NO-DF (27.4%) and CL-NO-DF (24.0%) ovaries than from CL-DF (16.2%), RCL-DF (15.4%), and lowest (P<0.05) from ANEST (8.8%). In Experiment 2, oocytes from the dominant follicle had a higher (P<0.05) cleavage rate (65.2 %) and transferable embryo yield (30.2%) than those collected from the largest subordinate and subordinate follicles. In conclusion, oocyte competence depended on the morphofunctional state of ovaries. Oocyte development was maximal in pairs of ovaries with a corpus hemorragicum or CL and no dominant follicle; in paired ovaries with a CL and a dominant follicle, development was maximal in oocytes derived from the dominant follicle.  相似文献   

5.
Eight new species of the genus Ptilonyssus (Berl. et Troues.) (Gamasina: Rhinonyssidae) from nasal cavities of the passeriformes from territory of the former USSR are described: P. ammomani sp. n. from Ammomanus deserti (Alaudidae) collected in Turkmenistan; P. spini sp. n. from Spinus spinus (Fringillidae) of Kaliningrad district (Russia); P. ripariae sp. n. from Riparia riparia (Hirundinidae) and P. acanthopneustes sp. n. from Phylloscopus borealis (Sylviidae) collected in Tjumen district (Russia); P. pyrrhulinus sp. n. from Pyrrhula pyrrhula (Fringillidae) and P. anthi sp. n. from Anthus trivialis (Motacillidae) of Rjazan district; P. sylviicola sp. n. from Sylviae communis (Sylviidae) collected in Tatarstan; P. cyanosylviae sp. n. from Cyanosylvia svecica (Turdidae) collected from Novosibirsk district.  相似文献   

6.
AIMS: To characterize cellulolytic, hydrogen-producing clostridia on a comparable basis. METHODS AND RESULTS: H(2) production from cellulose by six mesophilic clostridia was characterized in standardized batch experiments using MN301 cellulose, Avicel and cellobiose. Daily H(2) production, substrate degradation, biomass production and the end-point distribution of soluble fermentation products varied with species and substrates. All species produced a significant amount of H(2) from cellobiose, with Clostridium acetobutylicum achieving the highest H(2) yield of 2.3 mol H(2) mol(-1) hexose, but it did not degrade cellulose. Clostridium cellulolyticum and Clostridium populeti catalysed the highest H(2) production from cellulose, with yields of 1.7 and 1.6 mol H(2 )mol(-1) hexose from MN301 and 1.6 and 1.4 mol H(2) mol(-1) hexose from Avicel, respectively. These species also achieved 25-100% higher H(2) production rates from cellulose than the other species. CONCLUSIONS: These cellulolytic, hydrogen-producing clostridia varied in H(2) production, with Cl. cellulolyticum and Cl. populeti achieving the highest H(2) yields and cellulose degradation. SIGNIFICANCE AND IMPACT OF THE STUDY: The fermentation of cellulosic materials presents a means of H(2) production from renewable resources. This standardized comparison provides a quantitative baseline for improving H(2) production from cellulose through medium and process optimization and metabolic engineering.  相似文献   

7.
Seventeen agar samples were extracted from Gelidiella acerosa (Forsskal) Feldmann and Hamel (Rhodophyta, Gelidiales) specimens collected from nine different sites on the Indian coast-five from southeast coast and four from the west coast. The agar samples were analysed. The stability characteristics of the gels of selected agar samples were studied by rheometry under applied stress conditions, i.e. variation of the storage (G') and loss moduli (G') were studied under varying frequency and duration (time) of the stress applied. Yield, apparent and dynamic viscosities, gelling and melting temperatures, 3,6-anhydrogalactose (3,6-AG), sulphate contents and TGA (Thermogravimetric Analysis) measurements of the products were done. It was observed that the best quality agar was produced by G. acerosa occurring in the Gulf of Mannar region in the southeast coast. The gel strengths and the viscosities of agars extracted from Gelidiella acerosa occurring in the Gulf of Mannar ranged from 500 to 700gcm(-2) and 33 to 45cP for 2001 collections and for 2002 collections the corresponding values were 450 to 845gcm(-2) and 55 to 67cP respectively. On the other hand, for the agar samples extracted from the west coast of India, the gel strength and viscosities values ranged from 225 to 400gcm(-2) and from 15 to 30cP, respectively. The agars obtained from G. acerosa collected from southeast coast have been found to be suitable for bacterial culture and molecular biology. This is the first report of superior quality of agar from the Indian agarophytes.  相似文献   

8.
Stereochemical aspects of the formation of double bonds in abscisic acid   总被引:2,自引:1,他引:1  
The stereochemistry of the hydrogen elimination that occurs during the formation of the Delta(4)- and Delta(2)'-double bonds of abscisic acid has been determined from the (14)C/(3)H ratios in abscisic acid biosynthesized by avocado fruit from [2-(14)C,(2R)-2-(3)H(1)]-, [2-(14)C,(2S)-2-(3)H(1)]- and [2-(14)C,(5S)-5-(3)H(1)]-mevalonate. Setting the (14)C/(3)H ratio at 3:3 for [2-(14)C,(2R)-2-(3)H(1)]mevalonate, the corresponding ratio in derived methyl abscisate was 3:2.28; the analogous ratio for methyl abscisate from [2-(14)C,(2S)-2-(3)H(1)]mevalonate was 3:1.63. Removal of the 3'-hydrogen atom of abscisic acid by base-catalysed exchange altered the ratios to 3:1.55 and 3:1.44 respectively. It was concluded that this 3'-hydrogen atom is derived from the pro-2R-hydrogen atom of mevalonate. Removal of the 4-hydrogen atom from methyl abscisate by formation of a derivative, a lactone, lacking this hydrogen atom changed the ratio to 3:1.04 for material derived from [2-(14)C,(2R)-2-(3)H(1)]-mevalonate and to 3:1.05 for [2-(14)C,(2S)-2-(3)H(1)]mevalonate, showing that this hydrogen atom also is derived from the pro-2R-hydrogen atom of mevalonate. These ratios of the lactones are consistent with their retaining one (3)H atom at the 6'-methyl position of abscisic acid from the [(2R)-2-(3)H(1)]- and [(2S)-2-(3)H(1)]-mevalonate. The presence of some label at positions 3' and 4 when [(2S)-2-(3)H(1)]mevalonate was the precursor is attributed to the action of isopentenyl pyrophosphate isomerase. The hydrogen atom at C-5 of abscisic acid is derived from the pro-5S-hydrogen atom of mevalonate.  相似文献   

9.
Although Petunia axillaris subsp. axillaris is described as a self-incompatible taxon, some of the natural populations we have identified in Uruguay are composed of both self-incompatible and self-compatible plants. Here, we studied the self-incompatibility (SI) behavior of 50 plants derived from such a mixed population, designated U83, and examined the cause of the breakdown of SI. Thirteen plants were found to be self-incompatible, and the other 37 were found to be self-compatible. A total of 14 S-haplotypes were represented in these 50 plants, including two that we had previously identified from another mixed population, designated U1. All the 37 self-compatible plants carried either an S(C1)- or an S(C2)-haplotype. S(C1)S(C1) and S(C2)S(C2) homozygotes were generated by self-pollination of two of the self-compatible plants, and they were reciprocally crossed with 40 self-incompatible S-homozygotes (S(1)S(1) through S(40)S(40)) generated from plants identified from three mixed populations, including U83. The S(C1)S(C1) homozygote was reciprocally compatible with all the genotypes examined. The S(C2)S(C2) homozygote accepted pollen from all but the S(17)S(17) homozygote (identified from the U1 population), but the S(17)S(17) homozygote accepted pollen from the S(C2)S(C2) homozygote. cDNAs encoding S(C2)- and S(17)-RNases were cloned and sequenced, and their nucleotide sequences were completely identical. Analysis of bud-selfed progeny of heterozygotes carrying S(C1) or S(C2) showed that the SI behavior of S(C1) and S(C2) was identical to that of S(C1) and S(C2) homozygotes, respectively. All these results taken together suggested that the S(C2)-haplotype was a mutant form of the S(17)-haplotype, with the defect lying in the pollen function. The possible nature of the mutation is discussed.  相似文献   

10.
Electrostatic binding sites of extracellular polymeric substances (EPS) were characterized from titration data using linear programming analysis. Test results for three synthetic solutions of given solutes comprising amino, carboxyl, and phenolic groups indicated that this method was able to identify the electrostatic binding sites. For the six sites with pK(a) between 3 and 10, the estimated pK(a) deviated 0.11 +/- 0.09 from the theoretical values, and the estimated concentrations deviated 3.0% +/- 0.9% from the actual concentrations. Two EPS samples were then extracted from a hydrogen-producing sludge (HPS) and a sulfate-reducing biofilm (SRB). Analysis of charge excess data in titration from pH 3 to 11 indicated that the EPS of HPS comprised of five electrostatic binding sites with pK(a) ranging from 3 to 11. The pK(a) values of these binding sites and the possible corresponding functional groups were pK(a) 4.8 (carboxyl), pK(a) 6.0 (carboxyl/phosphoric), pK(a) 7.0 (phosphoric), pK(a) 9.8 (amine/phenolic), and pK(a) 11.0 (hydroxyl). EPS of the SRB comprised five of similar binding sites (with corresponding pK(a) values of 4.4, 6.0, 7.4, 9.4, and 11.0), plus one extra site at pK(a) 8.2, which was likely corresponding to the sulfhydryl group. The total electrostatic binding site concentration of EPS extracted from HPS were 10.88 mmol/g-EPS, of which the highest concentration was from the site of pK(a) 11.0. The corresponding values for the EPS extracted from SRB were 16.44 mmol/g-EPS and pK(a) 4.4. The total concentrations of electrostatic binding sites found in this study were 20- to 30-fold of those reported for bacterial cell surface, implying that EPS might be more crucial in biosorption of metals than bacterial cell surface in wastewater treatment and in bioremediation.  相似文献   

11.
Ecotoxicity assessment is essential before placing new chemical substances on the market. An investigation of the use of the chromatographic retention (log k) in biopartitioning micellar chromatography (BMC) as an in vitro approach to evaluate the toxicity in fish of pesticides (acute toxicity levels as pLC(50)) is proposed. A heterogeneous data set of 85 pesticides from six chemical families with available experimental fish toxicity data (ECOTOX database from U.S. Environmental Protection Agency (EPA)) was used. For pesticides exhibiting non-polar narcosis mechanism in fish (non-specific toxicity), more reliable models and precise pLC(50) estimations are obtained from log k (quantitative retention-activity relationships, QRAR) than from log P (quantitative structure-activity relationships, QSAR) or ECOSAR (ECOSAR program from U.S. EPA).  相似文献   

12.
Despite the huge burden of tuberculosis (TB) in Nigeria, case detection rate of infectious cases still remain low, thus constituting obstacle to eradication of the disease in the community. We carried out a 15 month (1st January 2008 to 30th March 2009) retrospective review of epidemiology of clinical isolates of M. tuberculosis isolated at TB regional reference laboratory at the department of Medical Microbiology and Parasitology, University College Hospital, Ibadan, Nigeria. Fifty isolates were recovered from 720 specimens during the period of study with a recovery rate of 6.9%. Sixty- two (8.6%) of the specimens were contaminated. Thirty eight (76.0%) isolates were from the specimens of male subjects and 12 (24.0%) from female subjects giving a male to female ratio of 3.2: 1.0 Majority (62.0%) of the isolates were from subjects aged 20 years and above with an isolation rate of 7.3% while only two clinical isolates (4.0%) were recovered from specimens from children. A high yield of 20.8% was recovered from specimen collected from Hausa ethnic group who predominantly domiciled in a particular part of the metropolis. In terms of socio-economic status, clinical isolates recovered from specimens from unskilled workers (76.0%) was more than thrice from that obtained from the professionals (24.0%). Seven (14.0%) of the total isolates were recovered from extra-pulmonary lesions while the majority 43 (86.0%) were for pulmonary TB. The isolation rate from children and extra-pulmonary sites are low. This suggests a need to pay more attention to diagnosis of childhood and extra-pulmonary TB in Ibadan, Nigeria.Keywords: M. tuberculosis, Isolates, Epidemiology, Ibadan.  相似文献   

13.
The scale function in wavelet transformation (WT) determines wavelet dilation and optimises the processing of a given signal. Here, the objective was to determine the influence of the scale function on the WT of 160 surface electromyograms using second-degree polynomial (WT(poly)) and exponential (WT(exp)) scale functions. For each WT, a mean frequency (MNF) was calculated from the original wavelet spectrum and from the cubic spline interpolated wavelet spectrum, and these were compared with the MNF obtained from a fast Fourier transform (FFT). The total intensity (Tp) for each WT was compared with the root mean square (RMS). The MNFs computed from the original wavelet spectra were significantly (P < 0.05) lower and higher when computed from the reconstructed wavelet spectra than those from the FFT. The Tp computed from WT(poly) showed significantly higher agreement with the RMS than the Tp from WT(exp). Finally, the WT(poly) may serve as a reference in electromyography.  相似文献   

14.
Examination of 200 samples from soil and the same number of samples from healthy human feces yielded 49 (24.5%) and 105 (52.5%) strains of heat-resistant Clostridium perfringens respectively. Fourteen (7.0%) strains isolated from soil and 37 (18.5%) from feces synthesized enterotoxin, as demonstrated by Tórtora's method, at sufficient levels to permit its detection by mouse lethality, microslide double gel diffusion or counterimmunoelectrophoresis tests. By using the Duncan-Strong (DS) method, only four (2%) enterotoxigenic strains from soil and 14 (7.0%) from feces were obtained. The supernatant fluid from two enterotoxigenic-negative strains grown in DS medium gave a false-positive reaction when they were injected intravenously into mice. Tórtora's medium was preferable because a larger number of isolated strains produced spores and enterotoxin to permit their recognition as enterotoxigenic strains.  相似文献   

15.
A total of 200 marine fishes (36 species) from the Caribbean Sea off Belize were examined for digenetic trematodes and 163 (81.5%) harbored at least one species. Five species are described as new: Lasiotocus asymmetricus (Monorchiidae) from Haemulon flavolineatum; Stephanostomum belizense (Acanthocolpidae) from Caranx bartholomaei; Neolepidapedon belizense (Lepocreadiidae) from Sphyraena barracuda; Opecoeloides belizensis (Opecoelidae) from Priacanthus arenatus; Saturnius belizensis (Hemiuridae) from Mugil curema. 72 previously known species were identified, and all represent new geographical distribution records while many are recorded from new hosts. Their zoogeographical affinities are very strongly with the tropical western Atlantic, although some also occur in the eastern Atlantic, Mediterranean, and Indo-Pacific regions.  相似文献   

16.
Phosphodiesterase activity is estimated in extracts and partially purified preparations from functionally different parts of bovine tongue. The enzyme activity varied from 4.0 to 10.4 nmole/mg of protein/min. Properties of phosphodiesterase from circumvallate papillae are studied, the pH optimum being 8.0--8.5, Km for cAMP--1.5.10(-4) M and for cGMP--6.5.10(-5) M. The enzyme activity did not change after the treatment with trypsin, protamine sulphate (0.01--1.0%), heparin (0.01--1.0) and taste agents: L-leucine (from 1.10(-2) M to 1.10(-5) M), quinine (from 4.10(-3) M to 4.10(-8) M) and D-glucose (from 1.10(-1) M to 1.10(-4) M). The protein inhibitor of the enzyme, isolated from retina external rod-cell segments considerably suppressed phosphodiesterase activity, and the protein activator from brain tissue stimulated it insignificantly. Thermostable protein modulators, which inhibit or activate (depending on experimental conditions) phosphodiesterase activity, are isolated from circumvallate papillae.  相似文献   

17.
Yeoh HH  Badger MR  Watson L 《Plant physiology》1981,67(6):1151-1155
Studies of ribulose-1,5-bisphosphate (RuBP) carboxylase from taxonomically diverse plants show that the enzyme from C(3) and crassulacean acid metabolism pathway species exhibits lower K(m)(CO(2)) values (12-25 micromolar) than does that from C(4) species (28-34 micromolar). RuBP carboxylase from aquatic angiosperms, an aquatic bryophyte, fresh water and marine algae has yielded consistently high K(m)(CO(2)) values (30-70 micromolar), similar in range to that of the enzyme from C(4) terrestrial plants. This variation in K(m)(CO(2)) is discussed in relation to the correlation between the existence of CO(2)-concentrating mechanisms for photosynthesis and the affinity of the enzyme for CO(2). The K(m)(RuBP) of the enzyme from various sources ranges from 10 to 136 micromolar; mean +/- sd = 36 +/- 20 micromolar. This variation in K(m)(RuBP) does not correlate with different photosynthetic pathways, but shows taxonomic patterns. Among the dicotyledons, the enzyme from crassinucellate species exhibits lower K(m)(RuBP) (18 +/- 4 micromolar) than does that from tenuinucellate species (25 +/- 7 micromolar). Among the Poaceae, RuBP carboxylase from Triticeae, chloridoids, andropogonoids, Microlaena, and Tetrarrhena has yielded lower K(m)(RuBP) values (29 +/- 11 micromolar) than has that from other members of the grass family (46 +/- 10 micromolar).  相似文献   

18.
The product distributions for the reactions of dihydroxyacetone phosphate (DHAP) in D(2)O at pD 7.9 catalyzed by triosephosphate isomerase (TIM) from chicken and rabbit muscle were determined by (1)H NMR spectroscopy using glyceraldehyde 3-phosphate dehydrogenase to trap the first-formed products of the thermodynamically unfavorable isomerization reaction, (R)-glyceraldehyde 3-phosphate (GAP) and [2(R)-(2)H]-GAP (d-GAP). Three products were observed from the reactions catalyzed by TIM: GAP from isomerization with intramolecular transfer of hydrogen (18% of the enzymatic products), d-GAP from isomerization with incorporation of deuterium from D(2)O into C-2 of GAP (43% of the enzymatic products), and [1(R)-(2)H]-DHAP (d-DHAP) from incorporation of deuterium from D(2)O into C-1 of DHAP (40% of the enzymatic products). The ratios of the yields of the deuterium-labeled products d-DHAP and d-GAP from partitioning of the intermediate of the TIM-catalyzed reactions of GAP and DHAP in D(2)O are 1.48 and 0.93, respectively. This provides evidence that the reaction of these two substrates does not proceed through a single, common, reaction intermediate but, rather, through distinct intermediates that differ in the bonding and arrangement of catalytic residues at the enediolate O-1 and O-2 oxyanions formed on deprotonation of GAP and DHAP, respectively.  相似文献   

19.
The present study was performed to determine the infection status of anisakid larvae in marine fish collected from 3 sea areas of the Republic of Korea. Total 86 marine fish (8 species) collected from the East Sea (Goseong-gun, Gangwon-do), 171 fish (10 species) from the South Sea (Sacheon-si, Gyeongsangnam-do), and 92 fish (7 species) from the Yellow Sea (Incheon Metropolitan City) were examined by both naked eyes and artificial digestion method. Among the total of 349 fish examined, 213 (61.0%) were infected with 8 species of anisakid larvae, i.e., Anisakis simplex, 6 types of Contracaecum spp., and Raphidascaris sp., and the mean larval density was 13.8 per infected fish. Anisakid larvae were detected in 45 fish (52.3%) from the East Sea, 131 fish (76.6%) from the South Sea, and 37 fish (40.2%) from the Yellow Sea. The average numbers of larvae detected were 4.0, 16.6, and 15.9, respectively. Anisakis simplex larvae were detected in 149 fish (42.7%), and the mean larval density was 9.0 per infected fish. They were found in 26 fish (30.2%) collected from the East Sea, 96 fish (56.1%) from the South Sea, and 27 fish (29.3%) from the Yellow Sea. The average numbers of larvae detected were 2.9, 10.3, and 10.5, respectively. Conclusively, the present study suggests that the infection rate and density of anisakid larvae are more or less higher in the fish from the South Sea than those from the East Sea or the Yellow Sea.  相似文献   

20.
A trial was conducted to study the effect of sire line (Duroc (DU) and Pietrain (PI)) on carcass, meat and fat quality of pigs reared outdoor and destined to dry-cured meat production. No differences between sire genotypes were detected in carcass fat thickness (P > 0.10) but carcasses from DU-sired pigs were longer (P < 0.05) and tended to have a higher yield of trimmed shoulders (P = 0.07) and hams (P = 0.06) than carcasses from PI-sired pigs. Loins from DU-sired genotype showed higher (P < 0.05) L* value and lower (P < 0.01) a* value than loins from PI-sired genotype. Pork from DU-sired offspring tended to have higher (P = 0.09) intramuscular fat (IMF) percentage and lower (P < 0.05) moisture proportion than meat from PI-sired offspring. Also, loins from DU-sired pigs had lower (P < 0.001) thawing losses than loins from PI-sired pigs. The subcutaneous fat from the DU-sired line tended to show lower (P = 0.08) percentage of total polyunsaturated fatty acids (PUFAs) than that from the PI-sire line, mostly due to the higher proportion of C18:2 (P = 0.09) and C20:3 (P < 0.01). However, no effect of crossbreed was detected on the total proportion of saturated, monounsaturated fatty acid (MUFAs) or PUFAs of IMF (P > 0.10). We conclude that both sire lines can be used successfully under outdoor conditions but DU boars are more adequate than PI boars for the production of heavy pigs intended for the dry-cured meat industry.  相似文献   

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