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11.
12.
The larvicidal activity of a number of 1-(substituted benzoyl)-2-benzoyl–1 -ten-butylhydrazines against the rice stem borer (Chilo suppressalis Walk.) was measured. Variations in the activity were examined quantitatively using physico-chemical substituent and molecular parameters and regression analysis. The results indicated that the molecular hydrophobicity and the electron-withdrawing inductive/ field effect of ontho substituents are favourable to larvicidal activity. The bulkiness of substituents at the meta and para positions was unfavourable to activity, substitution at the para position being more unfavourable than that at the meta position in terms of van der Waals' volume. The 2,3–, 2,5- and 2,6-disubstitution patterns were also unfavourable to activity. Reductions in larvicidal activity caused by the 2,6-,- 2,3,5- and 2,3,4,5-substitutions were greater than those induced by the 2,3- and 2,5-disubstitutions. When the sum of contributions from favourable effects is greater than that from unfavourable effects, the larvicidal activity is expected to be superior to that of the unsubstituted compound.  相似文献   
13.
The variations in the light-dependent herbicidal activity against Echinochloa oryzicola of a number of 4-pyridone-3-carboxanilides with various substituents on the anilide and pyridone rings have been examined by use of physicochemical substituent parameters and regression analysis. The effects of substituents of the anilide ring were such that the activity was related parabolically not only with the substituent hydrophobicity (π) but also with the steric bulk parameter (Es) of the bulkier ortho substituent. The effect of substituents at the 1-position of the pyridone ring was analysed with steric(STERIMOL L and B5) and electronic(γ1) parameters. That of substituents at the 5-position of the pyridone ring was explained by a parabolic function of a steric (MR) parameter. Analyses of the activity of 105 analogs confirmed that our previous selection of a candidate compound in this series for field trials was indeed appropriate in terms of physicochemical substituent effects.  相似文献   
14.
The ability to stimulate N-acetylglucosamine (GluNAc) incorporation in-vitro of a number of N-tert-butyl-N,N′-dibenzoylhydrazines having various substituents on both phenyl rings was measured in cultured integument excised from the rice stem borer (Chilo suppressalis Walker). The relationship between in-vitro and larvicidal potency was approximately linear. The substituent effects on variations in the potency were similar between in-vitro and larvicidal activities. An inhibitor of oxidative detoxication, piperonyl butoxide, had no synergistic effects on the in-vitro potency. The ability of some dibenzoylhydrazines to inhibit GluNAc incorporation at exposure periods longer than the optimum for stimulation was also measured in a similar cultured integument system. The relationship between the inhibitory and stimulatory potency indices was linear, indicating that the larvicidal activity of dibenzoylhydrazines is closely related to its ability to stimulate as well as to inhibit GluNAc incorporation into the larval cuticle.  相似文献   
15.
The effects of the oxadiazine insecticide indoxacarb and its N-decarbomethoxylated metabolite (DCJW) on tetrodotoxin-resistant (TTX-R) voltage-gated sodium channels in rat dorsal ganglion neurons were studied using the whole-cell patch clamp technique. Indoxacarb and DCJW suppressed the peak amplitude of action potentials, and DCJW exhibited a faster time course and higher potency than indoxacarb in the blocking effects. In voltage-clamp experiments, indoxacarb and DCJW suppressed TTX-R sodium currents in a time-dependent manner without a steady-state level of suppression. IC50 values for indoxacarb and DCJW on TTX-R sodium currents were estimated to be 10.7 and 0.8 microM after 25 min of bath application, respectively. DCJW was about 10 times more potent than indoxacarb in blocking TTX-R sodium currents. Although the suppressive effects of indoxacarb were partially reversible after washout with drug-free external solution, no recovery of sodium current was observed in DCJW treated neurons after prolonged washout. In current-voltage relationships, both indoxacarb and DCJW blocked the sodium currents to the same degree in the entire range of membrane potentials. The sodium conductance-voltage curve was not shifted along the voltage axis by indoxacarb and DCJW at 10 microM. In contrast, the steady-state inactivation curves were shifted in the hyperpolarizing direction by indoxacarb as well as by DCJW. Based on these results, it was concluded that indoxacarb and DCJW potently blocked the TTX-R sodium channel in rat DRG neurons with hyperpolarizing shifts of the steady-state inactivation curves, suggesting preferential association of the insecticides to the inactivated state of sodium channels. The small structural variation between indoxacarb and DCJW resulted in clear differences in potency for blocking sodium channels and reversibility after washout.  相似文献   
16.
To identify the effects of field pea hay (FPH) as a supplement of rice straw (RS) on feed intake and milk production of mid‐late lactation buffaloes in Tarai, Nepal, nine multiparous Murrah were fed a concentrate at 0.6% of their bodyweight (BW) on a concentrate dry matter (DM) basis daily while having ad libitum access to RS. The buffaloes were divided into three groups, and the experiment with three levels of FPH feeding was conducted at the following rate of BW: 0% (T1), 0.5% (T2) and 1.0% (T3) on an FPH DM basis. The DM intake (DMI) was higher in T2 and T3 than in T1. As the amount of FPH was raised, the BW change, crude protein intake (CPI) and total digestible nutrient intake (TDNI) was increased. Although the yield of milk and milk composition did not differ among the treatments, the 7% fat corrected milk yield (FCMY) tended to increase as FPH feeding amount was raised. Although there were no significant differences in FCMY/DMI and FCMY/TDNI among the treatments, FCMY/CPI decreased with FPH feeding. Supplementary FPH increased DMI, CPI and TDNI that might have raised BW, and tended to improve FCMY in mid‐late lactating buffaloes as a result of an increase in TDNI.  相似文献   
17.
A 12-year-old Thoroughbred gelding exhibited a unilateral exophthalmos on the left side. There had been no other clinical symptoms, such as rhinorrhea, before the first consultation. Clinical, hematologic, plasma biochemical, cytologic, and computed tomography (CT) examinations and complete necropsy were performed. These examinations did not reveal neoplastic lesions. CT images suggested that maxillary and frontal sinuses may have been filled with fluid. Cytologic and pathologic examinations revealed that the maxillary and orbital bones were pushed up with a large amount of the inflammatory fluid effused by chronic sinusitis. The CT and cytologic examinations were of great use for differential diagnosis in this case. This was an unusual case of exophthalmos induced by deformation of the orbital bones resulting from chronic sinusitis.  相似文献   
18.
Root and stem rot with wilt of above ground parts of cultivated chrysanthemums was first found in Ibaraki, Toyama and Kagawa prefectures, Japan in 2002 and 2003. Pythium species were isolated from the diseased tissues and identified as P. dissotocum, P. oedochilum, P. sylvaticum, P. ultimum var. ultimum and asexual strains of P. helicoides based on their morphologies and sequences of rDNA-ITS region. All the Pythium species were strongly pathogenic to chrysanthemums in pot conditions and were reisolated from the inoculated plants. Because Pythium root and stem rot of chrysanthemum has never been reported in Japan, we propose that this is a new disease that can be caused by the five Pythium species.  相似文献   
19.
In vivo matured oocytes collected by laparoscopic follicular aspiration (LFA) from hormone treated female goats were used as recipient ooplasts for somatic cell nuclear transfer (SCNT). Japanese native (Shiba) goats were used as donor females and some donor females were used repeatedly (two or three times) at intervals of a few months. To induce synchronization of estrus, a sponge containing 0.5 g of progesterone was inserted into the vagina of each goat for 14 days. These animals were also treated with follicle stimulating hormone (FSH) in a series of 8 injections over 4 days. The first FSH injection was administered on the morning of day 9 of sponge insertion. On the morning of day 13, 50 µg of gonadotropin‐releasing hormone (GnRH) was injected into each animal. Twenty‐nine hours after GnRH injection, LFA was performed. After removal of cumulus cells, collected oocytes with the first polar body were selected and enucleated for nuclear transfer. Anterior pituitary cells isolated from an adult male Shiba goat were transfected with a DNA fragment containing the enhanced green flourescent protein gene and the puromycin resistance gene. A single donor cell was inserted into the perivitelline space of each enucleated oocyte and fusion was induced with one electric pulse of 20 V for 10 µs. The SCNT goat eggs were cultured in chemically defined medium at 38.5°C in 5% CO2, 5% O2, 90% N2 for 9 days. By LFA, 396 oocytes were collected from a total of 30 females. After removal of cumulus cells, 64% of them extruded the first polar body. The percentage of SCNT goat eggs produced using in vivo matured oocytes which developed to the blastocyst stage (20–21%) was significantly higher (P < 0.05) than that produced with in vitro matured oocytes (3–8%).  相似文献   
20.
Research on sex-determining region Y-box 2 (SOX2)-positive pituitary stem/progenitor cells, as a source of hormone-producing cells, is progressing rapidly in rodents. However, the stem/progenitor cells supplying hormone-producing cells that are essential for growth, reproduction, and lactation in bovines have not yet been identified. In this study, we characterized SOX2-positive cells in the pituitary gland of dairy cattle (Holstein heifers) after sexual maturity. Immunofluorescence analysis revealed that the localization pattern of SOX2-positive cells in the dairy cattle pituitary gland was similar to that observed in the rodent pituitary gland; the marginal cell layer (MCL), dense cell clusters, and single cells scattered in the parenchyma of the anterior lobe. Furthermore, most of the SOX2-positive cells were positive for the pituitary stem/progenitor cell niche markers E-cadherin and cytokeratin 8+18, which have been reported in rodents. In addition, in the MCL of the anterior lobe, there was a subpopulation of SOX2-positive cells positive for paired-related homeobox 1 and 2, whereas negative for S100β. Moreover, in the parenchyma of the anterior lobe, co-localization of SOX2 and pituitary hormones was infrequent. In summary, this study reveals the localization of putative pituitary stem/progenitor cells positive for SOX2 in dairy cattle. These results provide valuable information to support further investigation of cell supply in the dairy cattle pituitary gland.  相似文献   
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