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排序方式: 共有461条查询结果,搜索用时 31 毫秒
391.
Mohsen Amiressami 《Journal of pest science》1973,46(4):52-55
Zusammenfassung Das Mycetom der Pappel-BlattlausPemphigus bursarius L. wurde lichtmikroskopisch untersucht.Bei allen Generationen trat nach der Behandlung mit verschiedenen Phosphorsäureester-lnsectiziden (E 605, Systox, Plantaced) in sublethaler Dosis zunächst eine Auflockerung im Plasma der in den Mycetomzellen gelagerten Symbionten auf, später zeigte sich eine Auflösung der Zellwand der Mycetomzellen und eine dadurch bedingte Zerstreuung der Symbionten. Schließlich war bei den Nymphen und der geflügelten Generation Chromatolyse und Pyknose der Kerne der Mycetomzellen zu beobachten. Bei den Embryonen der verschiedenen lebendgebärenden Generationen konnte keine Gifteinwirkung bei den Mycetomzellen festgestellt werden. Das bedeutet, daß trotz starker Schädigung der Muttertiere, das Gift nicht bis zu den Embryonen vordringen konnte.Über die Durchlässigkeit der Uteruswandung konnten bislang noch keine Untersuchungen durchgeführt werden, so daß über die Ursachen der Unversehrtheit der Embryonen zunächst nichts ausgesagt werden kann.
Summary The organe-coloured mycetom of the Poplar-lousePemphigus bursarius (L.) have been examined with a light microscope. By all generations of insects appear after injektion of various phosphor-acid-ester insecticide (E 605, Systox, Plantaced), in sublethal dose, a special loosening of plasma of the mycetom-cells, and later dissolving of mycetomal covering membranes, and finally dispersion of saccharomycetes of mycetomal cells. The effectiveness of insecticides in the nymph and flying insects generation has been expressed by cell-nucleus materials. I could not see any symptoms on mycetom cell of the embryos of various generations of insects. It is to indicate that, possibly no impairment of absorption or centripetal transport of insecticide has been forwarded to the embryos, accordingly the mechanisms of this very efficient absorption and centripetal transport in the insects-uterus has not yet been carefully studied.相似文献
392.
Zusammenfassung Es wurden die Wirkungen von Precocen I (PI) unter Laborverhältnissen auf die frühen L4 und Puppen vonCulex quinquefasciatus bei Konzentrationen von 0,001–10,0 ppm untersucht. Das Spektrum der PI-Wirkungen schloß die Larven-und Adulten-Mortalität bei 0,1–10,0 ppm ein. Die Verpuppungs-und Adultenschlüpf-Periode wurden bei Dosen von 0,001–5,0 ppm verzögert. Auf die larvalen Nachkommen vonC. qu. wirkte sich die PI-Behandlung (0,001–10,0 ppm) in verringerter Fekundität und Eischlüpfquote, verzögerte Larvenentwicklung und schließlichem Absterben aus.
Mit einer Abbildung und 4 Tabellen 相似文献
Effects of precocene I onCulex quinquefasciatus Say (Diptera, Culicidae)
The effects of precocene-I (PI) onCulex quinquefasciatus Say were studied under laboratory conditions by treating laboratory reared early 4th instar larvae and pupae with 0.001–10.0 ppm of PI. The range of PI effects included larval and adult mortalities at 0.1–10.0 ppm. Pupation and adult emergence periods were delayed at 0.001–5.0 ppm. Effects of PI were maintained to offsprings ofC. quinquefasciatus. These effects involved reduced fecundity, reduced egg hatchability and delayed larval offspring development and finally the death at 0.001–10.0 ppm of PI.
Mit einer Abbildung und 4 Tabellen 相似文献
393.
Efficiency of the geomorphologic instantaneous unit hydrograph method in flood hydrograph simulation
Several methods and models to simulate rainfall-runoff processes have been presented, and each of them has its own advantages and disadvantages. In the present study, different methods were applied to simulate the rainfall–runoff process over the Kasilian Watershed located in northern Iran, including Snyder, SCS, Trianglar, Rosso and Geomorphoclimatic unit hydrographs. The study was intended to compare the accuracy and reliability of a geomorphologic model with Snyder, SCS, Trianglar, Rosso and Geomorphoclimatic Unit hydrographs. In addition, this study attempted to determine the shape and dimensions of outlet runoff hydrographs in a 68.8 km2 area in the Kasilian Basin, which is located in the Mazandaran Province of Iran. The first twenty-one equivalent rainfall–runoff events were selected, and a hydrograph of outlet runoff was calculated for each. The peak time and peak flow of outlet runoff in the models were then compared, and the model that most efficiently estimated hydrograph of outlet flow for similar regions was determined. The comparison of calculated and observed hydrographs showed that the geomorphologic model had the most direct agreement for the parameters of peak time and peak flow of direct runoff. Statistical analyses of the models demonstrated that the geomorphological model had the smallest main relative and square error. The study's results confirm the high efficiency of the Geomorphoclimatic Unit Hydrograph and its ability to increase simulation accuracy for runoff and hydrographs. 相似文献
394.
Majid Esmaelizad Saber Jelokhani-Niaraki Khadije Hashemnejad Morteza Kamalzadeh Mohsen Lotfi 《Journal of veterinary science (Suw?n-si, Korea)》2011,12(4):363-371
The nucleotide sequence of the VP1 (1D) and partial 3D polymerase (3Dpol) coding regions of the foot and mouth disease virus (FMDV) vaccine strain A/Iran87, a highly passaged isolate (~150 passages), was determined and aligned with previously published FMDV serotype A sequences. Overall analysis of the amino acid substitutions revealed that the partial 3Dpol coding region contained four amino acid alterations. Amino acid sequence comparison of the VP1 coding region of the field isolates revealed deletions in the highly passaged Iranian isolate (A/Iran87). The prominent G-H loop of the FMDV VP1 protein contains the conserved arginine-glycine-aspartic acid (RGD) tripeptide, which is a well-known ligand for a specific cell surface integrin. Despite losing the RGD sequence of the VP1 protein and an Asp26→Glu substitution in a beta sheet located within a small groove of the 3Dpol protein, the virus grew in BHK 21 suspension cell cultures. Since this strain has been used as a vaccine strain, it may be inferred that the RGD deletion has no critical role in virus attachment to the cell during the initiation of infection. It is probable that this FMDV subtype can utilize other pathways for cell attachment. 相似文献
395.
The interrelationships among bean productivity, prevalence of pathogens in roots, seeds and soil, and root rot disease were described at the pod maturity stage in 13 commercial fields. The soil population and frequency of pathogens isolated from seeds varied by pathogen species and field location. Fusarium solani was the most prevalent fungus isolated from bean seeds and field soil compared to Rhizoctonia solani, Macrophomina phaseolina and F. oxysporum. Principal component analysis revealed that the first component explaining 32% of the total variance was correlated with the root rot index. PC1 was more strongly linked to root and seed infections in comparison with soil populations of pathogens. Based on a correlation between PC2 (accounting for 23% of the total variance) and the number of seeds per bean plant, charcoal, Fusarium and Rhizoctonia root rots were recognized as more important determinants of seed losses to root rot disease. There were correlations among the major pathogens infecting either roots or seeds of beans. These findings provide useful information for future experimental plans to optimize management strategies for bean root rots. 相似文献
396.
Nasrollah Ahmadi Ahmad Oryan Mohsen Ghane Bita Geramizadeh 《Journal of Equine Veterinary Science》2013
Schwannomas of the external auditory canal (EAC) are exceedingly rare in human beings and domestic animals. Herein we describe the clinicopathological and immunohistochemical features of a benign schwannoma arising in the EAC of a 2.5-year-old filly. Microscopically, the mass showed a spindle cell tumor composed of hypocellular Antoni type B areas as a myxomatous arrangement of mesenchymal cells and hypercellular Antoni type A areas displaying short fascicles of densely packed neoplastic cells in the collagenous stroma. Immunohistochemically, the tumor cells were diffusely positive for S100 protein and vimentin but negative for Ki67. It was concluded that schwannomas should be included in the differential diagnosis of EAC masses, and immunohistochemical markers such as S100 protein can strongly help in differentiating this tumor from other spindle cell tumors. 相似文献
397.
Fallah Mehrabadi Mohammad Hossein Ghalyanchilangeroudi Arash Ghafouri Seyed Ali Malekan Mohammad Ziafati Zahra Hosseini Hossein Mousavi Fatemeh Sadat Jabbarifakhr Masoumeh Aghaeean Leila 《Tropical animal health and production》2019,51(6):1737-1749
Tropical Animal Health and Production - Since 1998, Iran’s poultry industry has faced several outbreaks of low pathogenic avian influenza H9N2. Tissue samples were collected from a broiler... 相似文献
398.
Mohsen Eslami Navid Jahan‐Roshan Farhad Farrokhi‐Ardabili 《Reproduction in domestic animals》2019,54(3):486-497
The current study was designed to investigate the effect of idebenone (Id), an antioxidant on ram semen quality. Semen samples were collected, pooled and diluted in a Tris‐based extender supplemented with 0, 1, 2, 4 and 8 µM idebenone. Computer‐assisted sperm analysis was used to evaluate spermatozoa kinematics. Sperm viability and membrane functionality were assessed respectively, by eosin‐nigrosin staining and HOS test. Biochemical assays were carried out to measure different metabolites in spermatozoa and medium at 0, 24, 48 and 72 hr. Total and forward progressive motility were greater in 1, 2 and 4 µM idebenone treated groups compared to control at 24, 48 and 72 hr time points (p < 0.05). Semen supplementation with Id significantly increased viability and functionality of spermatozoa membrane during storage (p < 0.05). Lower amounts of lipid hydroperoxides in medium and spermatozoa were observed in Id‐treated groups compared to control one at 24 and 48 hr of storage (p < 0.05). Medium and spermatozoa amounts of malondialdehyde and nitric oxide were less in Id 4 µM group compared to the control at 72 hr (p < 0.05). Total antioxidant capacity values and superoxide dismutase activity of spermatozoa and medium were greater in 2 and 4 µM idebenone treated groups in comparison with the control at 72 hr (p < 0.05). Results of the current study indicated that ram semen supplementation with Id at 4 µM level improved quality by ameliorating nitrosative and peroxidative stress, hence could be considered as an antioxidant additive during storage at 4°C. 相似文献
399.
Leaching column experiments were conducted to determine the degree of mobility of heavy metals (HMs) and nutrients after the addition of municipal solid sewage sludge (MSS) in a sandy‐loam soil. Treatments were (1) soil application of low metal content MSS, (2) soil application of metal‐enriched municipal solid sewage sludge (EMSS), and (3) control. The MSS application represented a dose of 200 Mg dry weight (dw) ha–1. Soil columns were incubated at room temperature for 15 d and were irrigated daily with distilled water to make a total of 557 mm. Leachates were collected and analyzed for HMs and nutrients. The Ni and Pb added to soil via MSS and EMSS were found to be leached through the 20 cm columns of calcareous sandy soil although Ni and Pb concentrations in the percolate were small relative to the total amounts of metals applied. Losses of K+ from the EMSS, MSS, and control were 92.5, 82.0, and 52.5 kg ha–1, respectively. Losses of Mg2+ were in the range from 104.4 (control treatment) to 295.2 kg ha–1 (EMSS), while the loss of Ca2+ was in the range from 265.0 (control treatment) to 568.2 kg ha–1 (EMSS). The results showed that the amounts of P leached from EMSS (3.02 kg ha–1) and MSS (2.97 kg–1 ha–1) were significantly larger than those from the control treatment (1.54 kg ha–1). The geochemical code Visual MINTEQ was used to calculate saturation indices. Leaching of P in different treatments was controlled by rate‐limited dissolution of hydroxyapatite, β‐tri‐Ca phosphate, and octa‐Ca phosphate. The results indicate that application of MSS to a sandy soil, at the loading rate used in this study, may pose a risk in terms of groundwater contamination with Ni, Pb, and the studied nutrients. 相似文献
400.
This study was conducted to evaluate the redistribution of the heavy metals Cd, Cu, Pb, Ni, and Zn among different soil fractions by N fertilizers. In a lab experiment, soil columns were leached with distilled water, KNO3, NaNO3, NH4NO3, or Ca(NO3)2 · 4H2O. After leaching, soil samples were sequentially extracted for exchangeable (EXCH), carbonate (CARB), organic‐matter (OM), Mn oxide (MNO), Fe oxide (FEO), and residual (RES) fractions. Distilled water significantly increased the concentrations of Cd and Ni in EXCH fraction, while concentration of Cu and Zn did not change significantly. Application of KNO3, NaNO3, NH4NO3, or Ca(NO3)2 · 4H2O significantly increased the concentrations of Cd and Zn in EXCH fraction, while concentration of Pb and Ni was decreased. Application of all fertilizers caused an increase of Cu in the OM fraction. Moreover, leaching with these solutions significantly increased Cd [except in Ca(NO3)2 · 4H2O], Cu, and Zn concentrations in the CARB fraction, while Pb and Ni concentrations were decreased. With application of all leaching solutions, Zn in the EXCH, CARB, FEO, and MNO fractions was significantly increased, while Zn in the OM fraction did not change. The mobility index indicated that Ca(NO3)2 · 4H2O increased the mobility of Cd, Cu, and Zn in the soil, whereas NaNO3 decreased the mobility of Pb and Ni in the soil. The mobility index of Pb decreased by all leaching solutions. Thus, these results suggest that applying N fertilizers may change heavy‐metal fractions in contaminated calcareous soil and possibly enhance metal mobility and that N‐fertilization management therefore may need modification. 相似文献