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1.
《Small Ruminant Research》2003,47(3):227-231
Experiments were conducted to investigate the size distribution of goat steroidogenic luteal cells throughout pregnancy. Corpora lutea were collected from very early (<6 weeks), early (6–8 weeks), middle (9–14 weeks) or late (15–18 weeks) stages of pregnancy. Luteal tissue was dissociated into single-cell suspension by enzyme treatments. Cells were stained for 3β-hydroxysteroid dehydrogenase (3β-HSD) activity, a marker for steroidogenic cells. The steroidogenic cells covered a wide spectrum of size ranging from 5 to 45 μm in diameter. There was a significant increase in mean cell diameter (P>0.01) as pregnancy progressed. Mean diameter of 3β-HSD positive cells increased from 14.73±0.35 μm in the corpus luteum of very early pregnancy to 24.20±0.45 μm in the corpus luteum of late pregnancy. The ratio of large (>20 μm in diameter) to small (5–20 μm in diameter) luteal cells was 0.28:1.0 in very early pregnancy, with the 7.5–15 μm cell size class being dominant. However, the ratio of large-to-small luteal cells was increased to 1.77:1.0 μm as pregnancy advanced and 25–35 μm cell sizes became predominant. It is likely that small luteal cells could develop into large cells as pregnancy progresses. Development of pregnancy is also associated with an increase in size of steroidogenic luteal cells.  相似文献   

2.
《Mycological Research》2006,110(8):951-956
Anthracnose of lentil, caused by Colletotrichum truncatum is a serious threat to lentil (Lens culinaris) grown in western Canada. The teleomorph stage of this pathogen was induced to form under laboratory conditions. Random pairing of single conidium isolates enabled the identification of fertile isolates. The individual isolates of this fertile pair were crossed with 14 other isolates, and all isolates were also incubated alone. Self-sterility was observed for all 16 isolates tested. Three isolates did not produce perithecia with either tester isolate, and none of the isolates tested produced perithecia with both tester isolates. Perithecia were brown–black, superficial, solitary or in small groups, obpyriform to ovate or ampulliform, 200–520 × 110–320 μm (mean: 350 × 200 μm). Asci were cylindrical, narrowing slightly at the apex, unitunicate, evanescent, 53–142 × 5–14 μm (mean: 90 × 8 μm), and contained eight ascospores. Ascospores were hyaline, aseptate, oblong, 12–20 × 5–8 μm (mean: 15.7–6.7 μm). The characteristics agree with those described for the genus Glomerella, and the species was named G. truncata sp. nov. The morphology of the new species is compared with that of other species in the genus, and future research on G. truncata is described.  相似文献   

3.
Community-based assessment of protozoa is usually performed at a taxon-dependent resolution. As an inherent ‘taxon-free’ trait, however, body-size spectrum has proved to be a highly informative indicator to summarize the functional structure of a community in both community research and monitoring programs in aquatic ecosystems. To demonstrate the relationships between the taxon-free resolution of protozoan communities and water conditions, the body-size spectra of biofilm-dwelling protozoa and their seasonal shift and environmental drivers were explored based on an annual dataset collected monthly from coastal waters of the Yellow Sea, northern China. Body sizes were calculated in equivalent spherical diameter (ESD). Among a total of 8 body-size ranks, S2 (19–27 μm), S3 (28–36 μm), S4 (37–50 μm) and S5 (53–71 μm) were the top four levels in frequency of occurrence, while rank S1 (13–17 μm), S2 and S4 were the dominant levels in abundance. These dominants showed a clear seasonal succession: S2/S4 (spring)  S2/S4 (summer)  S4 (autumn)  S2 (winter) in frequency of occurrence; S1 (spring)  S4 (summer)  S2 (autumn)  S1 (winter) in abundance. Bootstrapped average analysis showed a clear seasonal shift in body-size spectra of the protozoa during a 1-year cycle, and the best-matching analysis demonstrated that the temporal variations in frequency of occurrence and abundance were significantly correlated with water temperature, pH, dissolved oxygen (DO), alone or in combination with chemical oxygen demand (COD) and nutrients. Thus, the body-size spectra of biofilm-dwelling protozoa were seasonally shaped and might be used as a time and cost efficient bioindicator of water quality in marine ecosystems.  相似文献   

4.
Sunn Pest, Eurygaster integriceps Puton (Hemiptera: Scutelleridae), is the most serious pest of wheat in West and Central Asia. Following harvest, the pest migrates from wheat fields to high elevations to escape high summer temperatures and, the following spring, moves back to the fields. In this work, Sunn Pest populations were monitored in 21 overwintering sites located in seven provinces (with 800–2500 m elevation) in Iran. Litter samples were taken twice in each site, once in July–November 2002 and again in March 2003. At each site 60 Artemesia sp. bushes were selected at random and litter from each bush was collected and the number of live male and female adult Sunn Pest counted. More Sunn Pests were collected in higher elevations in the first sampling. Golestan (893 m), Kermanshah (1583 m), and Qazvin (1675 m), located in valleys and surrounded by mountainous areas, had < 5 adults/bush. However Azarbayejan (1750 m), Markazi (1883 m), Kordestan (2067 m), and Esfahan (2141 m), located in mountainous areas and/or close to mountains, had 10–52 adults/bush. No noticeable changes in Sunn Pest populations were observed in 17 overwintering sites among 21 between the two sampling times. These results suggest that, after Sunn Pest moves to more highly elevated sites at aestivation time, most of them remain in these sites during overwintering before migration to wheat fields in the spring. Sunn Pest can be targeted for management in these areas during the fall and/or early spring as their movement is clearly limited.  相似文献   

5.
We report on the development and characterization of automated metal-free multiple-column nanoLC instrumentation for sensitive and high-throughput analysis of phosphopeptides with mass spectrometry. The system employs a multiple-column capillary LC fluidic design developed for high-throughput analysis of peptides (Anal. Chem. 2001, 73, 3011–3021), incorporating modifications to achieve broad and sensitive analysis of phosphopeptides. The integrated nanoLC columns (50 μm i.d. × 30 cm containing 5 μm C18 particles) and the on-line solid phase extraction columns (150 μm i.d. × 4 cm containing 5 μm C18 particles) were connected to automatic switching valves with non-metal chromatographic accessories, and other modifications to avoid the exposure of the analyte to any metal surfaces during handling, separation, and electrospray ionization. The nanoLC developed provided a separation peak capacity of ~250 for phosphopeptides (and ~400 for normal peptides). A detection limit of 0.4 fmol was obtained when a linear ion trap tandem mass spectrometer (Finnegan LTQ) was coupled to a 50-μm i.d. column of the nanoLC. The separation power and sensitivity provided by the nanoLC–LTQ enabled identification of ~4600 phosphopeptide candidates from ~60 μg COS-7 cell tryptic digest followed by IMAC enrichment and ~520 tyrosine phosphopeptides from ~2 mg of human T cells digests followed by phosphotyrosine peptide immunoprecipitation.  相似文献   

6.
Shed teeth have been proposed as trace element biomarkers. This study determined variations in the spatial distribution of Ca, K, Zn, Pb, Mn, Cu, and Sr in four anatomical locations: superficial enamel (SE, 0–10 μm), subsuperficial enamel (SSE, 10–30 μm), primary dentin (PD), and secondary dentin (SD). Five primary incisors were analyzed by micro Synchrotron Radiation X-Ray Fluorescence (μ-SRXRF). Two teeth had low concentrations of lead in the SE (<250 μg/g), while three contained very high lead concentrations in the SE (>2000 μg/g). Teeth were sliced, and five spot measurements (20 μm beam diameter) were accomplished in each location. The data are shown as absolute values and as the ratio between the different elements and Ca. The distribution of K was close to that of Ca. Zn was the third most abundant element, with the highest levels being found in the SE and SD and low levels detected in the PD. Increasing Sr levels were found progressing from the enamel to the dentin, with the highest levels being found in the SD, a distribution that was unique. Pb, Mn, and Cu exhibited a similar trend, with higher signals for these elements detected in the SE. This study provides preliminary data on the heterogeneous distribution of different elements in the tooth, highlighting the importance of the first 10 μm of the SE for determination of some elements, such as Zn, Pb, Mn, and Cu.  相似文献   

7.
Marine toxic dinoflagellates of the genus Gambierdiscus are the causative agents of ciguatera fish poisoning (CFP), a form of seafood poisoning that is widespread in tropical, subtropical and temperate regions worldwide. The distributions of Gambierdiscus australes, Gambierdiscus scabrosus and two phylotypes of Gambierdiscus spp. type 2 and type 3 have been reported for the waters surrounding the main island of Japan. To explore the bloom dynamics and the vertical distribution of these Japanese species and phylotypes of Gambierdiscus, the effects of light intensity on their growth were tested, using a photoirradiation-culture system. The relationship between the observed growth rates and light intensity conditions for the four species/phylotypes were formulated at R > 0.92 (p < 0.01) using regression analysis and photosynthesis-light intensity (P-L) model. Based on this equation, the optimum light intensity (Lmax) and the semi-optimum light intensity range (Ls-opt) that resulted in the maximum growth rate (μmax) and ≥80% μ max values of the four species/phylotypes, respectively, were as follows: (1) the Lmax and Ls-opt of G. australes were 208 μmol photons m−2 s−1 and 91–422 μmol photons m−2 s−1, respectively; (2) those of G. scabrosus were 252 and 120–421 μmol photons m−2 s−1, respectively; (3) those of Gambierdiscus sp. type 2 were 192 and 75–430 μmol photons m−2 s−1, respectively; and (4) those of Gambierdiscus sp. type 3 were ≥427 and 73–427 μmol photons m−2 s−1, respectively. All four Gambierdiscus species/phylotypes required approximately 10 μmol photons m−2 s−1 to maintain growth. The light intensities in coastal waters at a site in Tosa Bay were measured vertically at 1 m intervals once per season. The relationships between the observed light intensity and depth were formulated using Beer’s Law. Based on these equations, the range of the attenuation coefficients at Tosa Bay site was determined to be 0.058–0.119 m−1. The values 1700 μmol photons m−2 s−1, 500 μmol photons m−2 s−1, and 200 μmol photons m−2 s−1 were substituted into the equations to estimate the vertical profiles of light intensity at sunny midday, cloudy midday and rainy midday, respectively. Based on the regression equations coupled with the empirically determined attenuation coefficients for each of the four seasons, the ranges of the projected depths of Lmax and Ls-opt for the four Gambierdiscus species/phylotypes under sunny midday conditions, cloudy midday conditions, and rainy midday conditions were 12–38 m and 12–54 m, 1–16 m and 1–33 m, and 0 m and 0–16 m, respectively. These results suggest that light intensity plays an important role in the bloom dynamics and vertical distribution of Gambierdiscus species/phylotypes in Japanese coastal waters.  相似文献   

8.
A sensitive and selective quantitative method to determine α-fluoro-β-alanine (FBAL), 5-fluorouracil (5-FU), and capecitabine (Cape) from a single human plasma aliquot (50 μL) has been developed and validated. First, 5-FU and Cape were extracted by liquid–liquid extraction (LLE) using a mixture of acetonitrile and ethyl acetate. This was followed by derivatization with dansyl chloride. The dansyl-derivatives from 5-FU and Cape were further purified using LLE with methyl tertiary-butyl ether (MTBE) and analyzed using a reversed-phase analytical column “Primesep D” (2.1 mm × 50 mm; 5 μm) with embedded basic ion-pairing groups. The remaining aqueous phase containing FBAL was treated with dansyl chloride and the dansyl-FBAL was purified by solid phase extraction. Ultra high pressure liquid chromatography (UPLC) technology on a BEH C18 stationary phase column with 1.7 μm particle size was used for analysis of dansyl-FBAL. The method was validated over the concentration ranges of 10–10,000, 5–5000, and 1–1000 ng/mL for FBAL, 5-FU, and Cape, respectively. The results from assay validation show that the method is rugged, precise, accurate, and well suited to support pharmacokinetic studies where approximately 300 samples can be extracted and analyzed in 1 day.  相似文献   

9.
Henneguya jocu n. sp. (Myxosporea, Myxobolidae) is described from the gill lamellae of the marine teleost fish Lutjanus jocu, with a focus on ultrastructural and molecular features. This myxosporean forms subspherical cysts up to ∼260 μm × 130 μm long, and develops asynchronously. Mature myxospores ellipsoidal with a bifurcated caudal process. Myxospore length 10.9 ± 0.4 μm (n = 50); width, 8.2 ± 0.3 μm (n = 50); and thickness, 2.9 ± 0.5 μm (n = 50). Two equal caudal processes, 34.1 ± 1.0 μm long (n = 50); and total myxospore length, 45.2 ± 1.0 μm (n = 50). Two symmetric valves surround two ellipsoidal polar capsules, 5.0 ± 0.3 × 1.4 ± 0.2 μm (n = 20), each containing an isofilar polar filament forming 4–5 coils along the inner wall of these structures, as well as a binucleated sporoplasm presenting a spherical vacuole and several globular sporoplasmosomes. Both the morphological data and molecular analysis of the SSU rDNA gene identify this parasite as a new species of the genus Henneguya. Maximum Likelihood and Maximum Parsimony analyses further indicate that the parasite clusters within others marine Myxobolidae species, forming a group alongside other Henneguya species described from marine hosts.  相似文献   

10.
A kinetic study of atosiban was conducted following repeated intravenous administration in Wistar rats. Sample analysis was performed using liquid chromatography–tandem mass spectrometry (LC–MS/MS) following full validation of an in-house method. Eptifibatide, a cyclic peptide, was used as an internal standard (IS). The analyte and internal standard were extracted using solid phase extraction (SPE) method. Chromatographic separation was carried out using an ACE C18 5 μm 50 mm × 4.6 mm column with gradient elution. Mass spectrometric detection was performed using TSQ Quantum ultra AM. The lower limit of quantification was 0.01 μg/ml when 100 μl rat plasma was used. Plasma concentrations of atosiban were measured at 0 (pre-dose), 2, 15, 30, 45, 60, 120 min at the dosage levels of 0.125 mg/kg (low dose), 0.250 mg/kg (mid dose), and 0.500 mg/kg (high dose), respectively. Atosiban plasma concentration measured at Day 1 showed mean peak atosiban concentration (Cmax) 0.40, 0.57, 1.95 μg/ml for low, mid and high dose treated animals and mean peak concentration on Day 28 was 0.41, 0.88, 1.31 μg/ml on Day 28 for low, mid and high dose treated animals.  相似文献   

11.
The present study was carried out as part of an ongoing general survey for myxosporean parasites infecting tilapias in the River Nile, Egypt. In the present study, 77 Nile tilapia (Oreochromis niloticus) were collected from boat landing sites at Beni-Suef governorate, Egypt and examined for the myxosporean infection. The infection was encountered as a huge number of free spores in the kidney and the spleen. The infection showed a prevalence of 51.9% (40/77) for Myxobolus brachysporus while it was 25.9% (20/77) for Myxobolus israelensis. Mature spores of M. brachysporus were ellipsoidal and measured 8.6 × 13.2 μm. The polar capsules were subcircular with 5–6 filament turns and measured 4.7 × 3.6 μm. Spores of M. israelensis were ellipsoidal in the frontal view and fusiform in the lateral view. Spore measurements were 13.4 μm long and 8.7 μm wide. The polar capsules were elongated with 6–7 filament coils and measured 8.6 × 3.1 μm. The findings presented here proved that tilapia fishes in the Nile River are still suffering from infections with Myxobolus species. Therefore, further studies should be carried out to survey the Myxobolus infection among tilapias under culture conditions to clarify the pathological impacts of this parasite in tilapias aquaculture.  相似文献   

12.
《Theriogenology》2008,69(9):1228-1239
Understanding normal folliculogenesis in guinea pigs is fundamental as a first step towards the development of a guinea pig follicle culture system. The aims of this study were (1) to characterise morphological changes during follicular development in vivo and (2) to describe the growth pattern of follicles. Cycling guinea pigs were infused with 5-bromo-2′-deoxyuridine for 1 or 2 weeks and sacrificed at time points ranging from 0 to 37 days after the infusion. The granulosa cell number in the largest cross-sections increased from 25.0 ± 6.1 (mean ± S.D.) in primary (type 2) to 192.0 ± 65.9 in preantral (type 5) and 256.3 ± 96.9 in antral (type 6) follicles. The oocyte diameter increased from 44.8 ± 6.2 μm (type 2) to 72.8 ± 9.1 μm (type 5) and 78.9 ± 9.3 μm (type 6) and the follicle diameter from 67.9 ± 10.1 μm (type 2) to 188.9 ± 29.7 μm (type 5) and 231.0 ± 56.1 μm (type 6). After a 1-week labelling period, about 71% of type 2 follicles had at least one labelled granulosa cell, as did 95% of type 3–4, and 100% of type 5 and 6. About 1 week was needed to achieve 95% mitotic activity in granulosa cells (GC) of type 5 and 6 follicles, while about 2 weeks was required to achieve 100% mitotic activity in GC of type 3–4 and more than 2 weeks for GC of type 2 follicles. These data provide some baselines for the examination of a guinea pig follicle culture system.  相似文献   

13.
Herein, we report the synthesis and screening of cyano substituted biaryl analogs 5(am) as Peptide deformylase (PDF) enzyme inhibitors. The compounds 5a (IC50 value = 13.16 μM), 5d (IC50 value = 15.66 μM) and 5j (IC50 value = 19.16 μM) had shown good PDF inhibition activity. The compounds 5a (MIC range = 11.00–15.83 μg/mL), 5b (MIC range = 23.75–28.50 μg/mL) and 5j (MIC range = 7.66–16.91 μg/mL) had also shown potent antibacterial activity when compared with ciprofloxacin (MIC range = 25–50 μg/mL). Thus, the active derivatives were not only potent PDF inhibitors but also efficient antibacterial agents. In order to gain more insight on the binding mode of the compounds with PDF, the synthesized compounds 5(am) were docked against PDF enzyme of Escherichia coli and compounds exhibited good binding properties. In silico ADME properties of synthesized compounds were also analyzed and showed potential to develop as good oral drug candidates.  相似文献   

14.
The natural ability of the detoxification enzymes glutathione transferases (GSTs) to interact with xenobiotics can be used for the production of colorimetric assays. Detection is usually based on the inhibition of the GST-catalysed reaction, with detection achieved spectrophotometrically or electrochemically. Here we have adopted a chromogenic (visual) activity assay for screening GSTs with alkyltransferase activity for iodoalkene substrates for detection of insecticides. We screened a number of GSTs from insecticide resistant mosquito species for their ability to catalyse iodoalkane biotransformation reactions. AaGSTE2 was found to metabolise iodoethane with high turnover, which resulted in a dark blue colour in the enzymatic reaction. Following assay optimisation we exploited the high recognition affinity of the AgGSTE2 for insecticides to develop a novel colorimetric detection assay for organochlorine and pyrethroid quantification. Calibration curves were obtained for permethirn, deltamethrin, λ-cyhalothrin and DDT, with useful concentration ranges of 0–40 μg/ml (0–100 μM), 0–50 μg/ml (0–100 μM), 0–100 μg/ml (0–220 μM), and 0–50 μg/ml (0–140 μM), respectively. The assay was validated with extracts from insecticide sprayed surfaces and found to be reproducible and reliable compared with HPLC. The assay is therefore suitable for monitoring insecticide residues in insecticide treated materials, and therefore has potential for insect vector control operations.  相似文献   

15.
《Process Biochemistry》2007,42(4):693-699
The refining process of vegetable oils generates acidic wastewater with the following characteristics: pH (1–1.5), COD (10–30 g O2 L−1), suspended solids (7–12 g L−1) and fats (2–4 g L−1). In order to reduce the effluent load and recover a fraction of the fats without using any additives, a microfiltration (0.2–1.4 μm) process involving ceramic membranes at very low transmembrane pressure values (0.1–1 bar) was assessed. Four batches of acidic wastewater from different manufacturing runs were tested. Trials with a constant volumetric reduction ratio of 30 were carried out for periods of more than 5 h. With a 0.5 μm membrane it was possible to maintain a permeate flux of 100 L h−1 m−2 for 24 h and achieve a 91% reduction in SS, a 96% reduction in fat and a COD reduction of more than 60%. In addition, the retentate thus extracted separated spontaneously into two phases, both of which could be exploited: the upper phase mainly consisting of fats as a by-product and the lower clarified phase which could be mixed into the permeate.  相似文献   

16.
A method based on the on-line turbulent-flow chromatography and fast high-performance liquid chromatography/mass spectrometry (TFC–LC/MS) was developed for sensitive and high throughput pharmacokinetic study of traditional Chinese medicines (TCMs). In this method, an on-line extraction column (Waters Oasis HLB) and a fast HPLC column with sub-2 μm particle size (Agilent Zorbax StableBond-C18, 4.6 mm × 50 mm, 1.8 μm) in a column-switching set-up were utilized. HLB is a reversed-phase extraction column with hydrophilic–lipophilic balanced copolymer (2.1 mm × 20 mm, 25 μm particle size), which will exhibit some turbulent-flow properties at a high-flow rate. The method combines the speed and robustness of turbulent-flow extraction and the sensitivity and separation efficiency of fast HPLC–MS to analyze multiple and trace constituents of TCMs in plasma matrix. This method was successfully applied for pharmacokinetic study of verticine, verticinone and isoverticine, the chemical markers of Fritillaria thunbergii, after oral administration of total steroidal alkaloids extract of F. thunbergii to rats. Each plasma sample was analyzed within 7 min. The method demonstrated good linearity (R > 0.999) ranged from 0.505 to 96.0 ng/mL with satisfactory accuracy and precision, and the lower limit of quantifications of verticine, verticinone and isoverticine were estimated to be 0.120, 0.595 and 0.505 ng/mL, respectively. These results indicate that the proposed method is fast, sensitive, and feasible for pharmacokinetic study of TCMs.  相似文献   

17.
The methanolic extract from fresh stems of Cistanche tubulosa (Orobanchaceae) was found to show hepatoprotective effects against d-galactosamine (d-GalN)/lipopolysaccharide (LPS)-induced liver injury in mice. From the extract, three new phenylethanoid oligoglycosides, kankanosides H1 (1), H2 (2), and I (3), were isolated together with 16 phenylethanoid glycosides (419) and two acylated oligosugars (20, 21). The structures of 13 were determined on the basis of spectroscopic properties as well as of chemical evidence. Among the isolates, echinacoside (4, IC50 = 10.2 μM), acteoside (5, 4.6 μM), isoacteoside (6, 5.3 μM), 2′-acetylacteoside (8, 4.8 μM), and tubuloside A (10, 8.6 μM) inhibited d-GalN-induced death of hepatocytes. These five isolates, 4 (31.1 μM), 5 (17.8 μM), 6 (22.7 μM), 8 (25.7 μM), and 10 (23.2 μM), and cistantubuloside B1 (11, 21.4 μM) also reduced TNF-α-induced cytotoxicity in L929 cells. Moreover, principal constituents (46) exhibited in vivo hepatoprotective effects at doses of 25–100 mg/kg, po.  相似文献   

18.
《Small Ruminant Research》2009,85(1-3):89-99
We aimed to quantify the sources of variation contributing to the production and quality of cashmere produced in five districts in Osh and Naryn provinces of Kyrgyzstan. In early spring 2008 mid-side cashmere samples were taken from 719 cashmere adult females, and 41 cashmere adult males and castrates. Samples came from 53 villages and a total of 156 farmers’ flocks. For 91 goats from 33 farmers in 13 villages of two districts that had been sampled earlier, cashmere was combed from the goat at the time of a second visit (end of April 2008) when the cashmere would normally be harvested. Following standard cashmere objective measurement, data were examined using general linear modelling to quantify the effects of potential determinants. The mean fibre diameter (MFD) of cashmere differed between provinces (Osh 15.7 μm, Naryn 16.7 μm; P = 4.4 × 10−20). About 42% of the cashmere was <16 μm, 48% was 16.0–18.0 μm and 9.5% was >18.0 μm. Most of the cashmere samples were coloured (81%), with 63% black and 19% white. The percentage of cashmere samples that were white declined as MFD increased (26% < 14 μm to 11% of >18 μm). The primary determinants of cashmere MFD of individual goats were age of goat (range 1.46 μm, P = 1.8 × 10−12) and farm (range 6.5 μm, P = 1.7 × 10−14). The lesser effects detected for sex (range 0.9 μm, P = 0.026) and colour of cashmere (range 1.8 μm, P = 0.023) were based on small sample sizes and are unreliable. Age of goat had important affects on fibre diameter variation (up to 1.7% in coefficient of variation, P = 5.8 × 10−6) and fibre curvature (2.5–5°/mm, P = 2.1 × 10−4). By far the greatest effect on fibre curvature was cashmere MFD (P = 3.0 × 10−104) with a smaller effect of sex (about 5°/mm, P = 3.0 × 10−6). Village effects were detected on fibre diameter variability (range 4.5% in coefficient of variation, P = 0.027) and fibre curvature (range 15°/mm, P = 1.6 × 10−7). There was a strong negative association between increasing MFD and declining fibre curvature (−5.11 ± 0.181°/mm per 1 μm; P = 7.1 × 10−121; r2 = 0.51). Average combed cashmere weight was 164 g, the clean cashmere content was 0.661 and median clean cashmere production was 110 g per goat (range 60–351 g). Combed cashmere production increased with altitude of the village, probably related to different moulting times as spring temperatures warmed up later in higher altitude villages up to 3200 masl. Measurements of combed cashmere MFD were coarser than the mid-side samples taken earlier in the year. There are farmers and cashmere goats in the sampled districts of Kyrgyzstan which produce the finest qualities of commercial cashmere as the vast majority of cashmere is fine, has low variation in fibre diameter and has fibre crimping (curvature) typical of Chinese and Mongolian cashmere. There is substantial scope to increase the production and commercial value of cashmere produced by Kyrgyz goats. In particular, some villages and farmers need to change their buck selection practices if they wish to produce acceptable cashmere. Farmers should separate their finer and white cashmere prior to sale.  相似文献   

19.
The link between brain iron homeostasis and neurodegenerative disease has been the subject of extensive research. There is increasing evidence of iron accumulation during ageing, and altered iron levels in some specific brain regions in neurodegenerative disease patients have been reported.Using graphite furnace atomic absorption spectrometry after microwave-assisted acid digestion of the samples, iron levels were determined in 14 different areas of the human brain [frontal cortex, superior and middle temporal, caudate nucleus, putamen, globus pallidus, cingulated gyrus, hippocampus, inferior parietal lobule, visual cortex of the occipital lobe, midbrain, pons (locus coeruleus), medulla and cerebellum (dentate nucleus)] of n = 42 adult individuals (71 ± 12 years old, range: 53–101 years old) with no known history or evidence of neurodegenerative, neurological or psychiatric disorders.It was found that the iron distribution in the adult human brain is quite heterogeneous. The highest levels were found in the putamen (mean ± SD, range: 855 ± 295 μg/g, 304–1628 μg/g) and globus pallidus (739 ± 390 μg/g, 225–1870 μg/g), and the lowest levels were observed in the pons (98 ± 43 μg/g, 11–253 μg/g) and medulla (56 ± 25 μg/g, 13–115 μg/g).Globally, iron levels proved to be age-related. The positive correlation between iron levels and age was most significant in the basal ganglia (caudate nucleus, putamen and globus pallidus).Compared with the age-matched control group, altered iron levels were observed in specific brain areas of one Parkinson's disease patient (the basal ganglia) and two Alzheimer's disease patients (the hippocampus).  相似文献   

20.
A morphometric study on H. armigera antenna showed four styles of sensilla, i.e., styloconica, chaetica, coeloconica, and trichodea, and their numbers were estimated. Sensilla trichodea detect inter and intraspecific communication signals and was the most numerous. They were divided into three types: type I, the longest, with a length of 34.04 ± 3.16 μm and about 2.16 to 2.42 μm in diameter at its base; 2) type II, intermediate, with a length of 22.58 ± 0.77 μm and basal diameter of 1.8–2.52 μm; 3) type III, the shortest sensilla trichodea, with a length of 7.62 ± 0.4 μm and a range in diameter similar to that of type II. The length of the female sensilla trichodea was longer than that of the male. The total number of sensilla trichodea was estimated to be 7520 on the antenna of the female, and 6831 on the male antenna. The lengths of the sensilla trichodea type I and type III were significantly different on male (t = 4.6881, P = 0.0034) and female antenna (t = 18.9852, P = 0.0001). An estimation of the predicted surface area of the most numerous type I on sampled segments between the 12th and 20th segments from a female of H. armigera showed a surface area of 5 × 103 μm2 and a sensillar density of 38 sensilla/103 μm2. The fraction of sensilla-occupied surface area was 0.4 μm2.  相似文献   

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