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71.
Cupuassu (Theobroma grandiflorum) is a fruit tree native to the Brazilian Amazon. Cupuassu beans are extensively used in the Brazilian food industry. Fat from cupuassu beans, which are a rich source of triacylglycerols and fatty acids, is used extensively in the production of candies and confectionery in the northern and northeastern regions of Brazil. The potential use of the agro-industrial by-products of cupuassu has only slightly been addressed by the scientific community. Often, such by-products are sources of bioactive compounds with functional properties. Thus, the aims of this study were to characterize the use of cupuassu peel flour (CPF) and to examine the potential of CPF as a partial replacement in the preparation of breads through various means: chemical analyses, determination of protein digestibility, tannins, phytic acid and phenolic contents, pH, color, volume, and acceptance tests. The results show that CPF is a potential source of dietary fiber (79.81%), mainly insoluble fiber (78.29%), and breads made with added CPF present high dietary fiber content (5.40 and 6.15 g/100 g for inclusions with 6 and 9% CPF, respectively) and phytochemical values. The use of this by-product did not produce substantial changes in the physical, chemical or rheological characteristics of breads. Therefore, breads enhanced with CPF may be a convenient functional food, offering a good source of dietary fiber and phytochemicals. Breads prepared with 6% added CPF presented an acceptable overall quality to consumers.  相似文献   
72.
A 5-year-old Mangalarga mare was referred to the Veterinary Teaching Hospital of the Veterinary Medical School in Botucatu with a complaint of a persistent 2-month ovarian follicle which had grown progressively to 20 cm in diameter. Ultrasonography showed a circular, cystic structure in the right ovary, whose wall was thickened and interior was filled with anechoic content. Ovarian neoplasia was suspected, and a unilateral ovariectomy was performed through the paralumbar fossa, using general anesthesia through inhalation. Histopathological evaluation concluded that the ovarian enlargement was caused by a fibrothecoma. The present report describes features of fibrothecoma, which is extremely rare in the equine species.  相似文献   
73.
When applied at concentrations of one nM or higher to a house fly larval neuromuscular preparation, deltamethrin (DM) and fenvalerate (FV) greatly increased miniature excitatory postsynaptic potential (mepsp) rate and blocked neuromuscular transmission. The DM-induced mepsp discharge was abolished by tetrodotoxin (TTX), removal of Ca2+ from the saline, or by application of hyperpolarizing stimuli to the nerve, indicating that it was due to depolarization of the presynaptic terminals. Also, in the presence of TTX, K+ depolarization increased mepsp rate at the same external K+ concentration before and after DM treatment, confirming that DM released transmitter by depolarizing the nerve terminals rather than by altering the voltage dependence of transmitter release. The potassium channel blocker tetraethylammonium (TEA) increased mepsp rate somewhat, while aconitine (20 μM), which keeps sodium channels open, increased mepsp rate consistently. Pretreatment of nerves with a subthreshold dose of TEA greatly increased the mepsp rate-increasing activity of DM and aconitine, while a subthreshold level of aconitine did not synergize DM. These observations suggest that DM, like aconitine, depolarized nerves by modifying the sodium channels. Knockdown resistant (kdr) larvae were resistant to the depolarizing action of DM and aconitine but not to that of TEA, indicating that the kdr gene produced a modified sodium channel which was less sensitive to the action of pyrethroids and aconitine. During sustained transmitter release by DM, evoked release gradually declined, resulting in a condition called early block in which spontaneous release was high and release could be evoked by electrotonic depolarization of the nerve terminals, but not by a nerve action potential. Early block was probably due to conduction block in the nerve terminals. Early block eventually gave way to late block, characterized by the decline of spontaneous release to subnormal levels and complete failure of evoked release. After late block, the calcium ionophore X-537A could not release transmitter, suggesting that late block was due to depletion of available transmitter. DM did not have a direct effect upon extrasynaptic muscle membrane. However, after late block, muscles were left insensitive to the putative transmitters glutamate and aspartate when these were bath or iontophoretically applied. A low rate of mepsps persisted after late block, indicating that the muscles were still sensitive to the natural transmitters.  相似文献   
74.
Objective— To evaluate the effect of fracture and subsequent repair on future bone growth of the humerus after Salter–Harris type IV fracture of the lateral part of the humeral condyle (LPHC).
Study Design— Prospective study.
Animals— Dogs (n=11).
Methods— Dogs that had LPHC fracture and an open distal humeral physis repaired (1992–2006) were re-examined and radiographed at ≥12 months of age and humeral length was measured.
Result— Measurements from 11 dogs showed a significant ( P =.02) increase in length of the humeral diaphysis of the affected leg compared with that of the intact limb (median, 1.2%; range, 1.3–3.4%). Condylar deformity secondary to growth disturbance was not observed.
Conclusion— Shortening or growth deformity was not observed after fracture and repair even if a transcondylar screw was placed through the distal humeral growth plate. A mild overgrowth of the humeral diaphysis was observed, although likely considered clinically unimportant.
Clinical Relevance— Fracture of the LPHC and subsequent repair in dogs >3 months of age do not impair growth of the humeral diaphysis. A transcondylar humeral screw placed through the humeral physis will not result in shortening of the humeral diaphysis. Implant removal to allow for further growth is therefore not indicated.  相似文献   
75.
Objective— To report clinical findings, treatment, and outcome in dogs with acute (<7 days) oropharyngeal or esophageal stick injury. Study Design— Retrospective study. Animals— Dogs (n=41) with acute oropharyngeal or esophageal injury. Methods— Dogs had clinical and radiographic examination, and frequently, cervical surgical exploration. The decision to operate was based on radiographic findings of cervical emphysema. Outcome was determined by owner or veterinarian interview. Results— Of 41 dogs, 27 had oropharyngeal injury and 14 had esophageal injury. Five dogs with esophageal injury died. All dogs with radiographic evidence of cervical emphysema (n=34) had ventral median cervical exploration or necropsy; 11 had wood fragment(s) retrieved. In 7 dogs without radiographic signs of cervical emphysema, wounds involving the pharynx or soft palate were treated by local debridement and lavage using an oral approach. Mean follow‐up time was 36.4 months. All wounds healed without complication; however, 1 dog that was not surgically explored had a piece of wood surgically retrieved 3 months later. Conclusions— Radiographic evidence of cervical emphysema is a frequent finding in dogs with acute penetrating oropharyngeal or esophageal injury and indicates trauma to the deeper cervical tissues. Acute penetrating injury of the oropharyngeal region, when treated appropriately, has a better prognosis than acute esophageal penetration. Clinical Relevance— Ventral median cervical surgical exploration is recommended in dogs with acute penetrating injury of the oropharynx or esophagus if there is radiographic evidence of tissue emphysema.  相似文献   
76.
Two experiments were conducted to determine (i) factors influencing calf temperament at weaning, (ii) association between heifer–calf temperament at weaning and temperament at breeding and (iii) effect of heifer–calf temperament on pregnancy rate per artificial insemination (P/AI). In experiment 1, beef cows and their calves (n = 285) from three farms were used. Sire docility estimated progeny difference (EPD) score, birth type (normal or assisted), calf gender, calf behaviour (during 1st 4 weeks) and calf health status (until weaning) were recorded. Cows and calves were assigned a temperament score (0—calm; 1—excitable), and all cows were given a body condition score (BCS, 1–9; 1—emaciated; 9—obese) at weaning. Calf's illness (< .05), low sire docility EPD score (< .05), altered gait (< .05), altered resting behaviour (< .01), reduced/no play behaviour (< .05) and cow excitable temperament (< .001) increased calf excitable temperament at weaning. In experiment 2, replacement heifer–calves (n = 758) from 12 farms were assigned a temperament score at weaning and later at breeding. Blood from 40 calves at weaning and 31 heifers at initiation of synchronization (same animals) was collected by coccygeal venipuncture for determination of circulating cortisol and substance P concentrations. Heifers were assigned a BCS and reproductive tract score (RTS, 1–5; 1—immature, acyclic; 5—mature, cyclic), synchronized for fixed time AI, observed for oestrus and were artificially inseminated. Cortisol concentrations were increased in excitable heifer–calves compared to calm heifer–calves at weaning (< .05), and substance P was increased in excitable compared to calm females both at weaning and breeding (< .05). Low sire EPD docility score (< .01), heifer–calf excitable temperament at weaning increased excitable temperament at breeding (< .01). Controlling for BCS categories (< .01), oestrous expression (< .0001) and temperament at breeding by oestrous expression (< .05), the calf's excitable temperament at weaning (< .001) reduced P/AI (Calm, 62.7 (244/389) vs. Excitable, 53.4% (197/369); < .01). In conclusion, selection of docile cows and sires with greater docility EPD score should be given consideration to reduce calf excitement. Temperament in beef female can be detected earlier in their life and could be used as a tool in the selection process and to improve their performances.  相似文献   
77.
Insecticide penetration studies are usually done by applying a finite dose of material to a finite area of the integument in a solvent, such as acetone, that evaporates very quickly. The time-course of penetration is then measured either as the buildup of material inside the insect or as the decline of material recoverable in a surface wash. Pharmacokinetic models are often used to describe such experiments, but identical models can be formulated from diffusion theory. Diffusion theory was applied to obtain equations that describe the steady-state behavior of a single-layer integument with partitioning between integument and solutions, and a double-layer integument with partitioning between layers and between each layer and the adjacent solution. The steady-state flux equations for both models were first-order, and it was shown that this would be the case for steady-state flux through any number of layers. The steady-state analysis has two limitations. First, the assumption of a steady state implies that the concentration gradient across each layer of the integument is linear, and that this could not occur instantaneously. Second, the analysis assumes that material diffuses from a pool on the surface at some external concentration, whereas, ideally, it is applied as a plane source of infinite concentration. If the steady-state assumption is rejected, the diffusion equation can be solved exactly, using Green's function, for diffusion of a topically applied dose across the integument modeled as a homogeneous plate, if the concentration at the internal face is assumed to remain zero. An analytical expression is obtained for concentration as a function of time and position in the integument, and from it are calculated flux into the insect and disappearance of material recoverable in a solvent wash, where material is assumed to be recoverable to an arbitrary depth. For small values of recovery depth, recovery falls precipitously following application, then progressively more slowly as the experiment proceeds. This phenomenon has been seen in much published data, and is explained adequately for the first time by the theory presented here. Predicted flux into the insect rises with a delay and then falls, but its fall is not exponential, as is often assumed. Peak flux is predicted to be directly related to the diffusion coeficient. The impact of these results on the design of penetration experiments is discussed.  相似文献   
78.
BMP‐6 has been found to be important to ovarian cells and oocyte, as well as to uterus. Thus, this study investigated the effect of bone morphogenetic protein (BMP‐6) and recombinant follicle‐stimulating hormone (rFSH) alone or in combination on the in vitro culture (IVC) of isolated caprine secondary follicles (Experiment 1) and the mRNA levels for BMP receptors/Smad signalling pathway (BMPR1A, BMPR2, SMAD1, SMAD4, SMAD5, SMAD6, SMAD7 and SMAD8) in vivo and in vitro using BMP‐6 (Experiment 2). Secondary follicles were cultured in αMEM+ alone (control medium) or supplemented with BMP‐6 at 1 or 10 ng/ml and rFSH alone or the combination of both BMP‐6 concentrations and rFSH. The results from Experiment 1 showed that the antrum formation rate was higher in the BMP‐6 at 1 ng/ml (p < 0.05) than in MEM. In Experiment 2, the mRNA expression for BMPR2, SMAD1, SMAD5 and SMAD6 was detected in non‐cultured control and after in vitro culture (MEM and 1 ng/ml BMP‐6); while the expression of SMAD7 and SMAD8 mRNA was only detected after IVC, SMAD4 was only detected in the BMP‐6 at 1 ng/ml treatment. In conclusion, the low BMP‐6 concentration positively influenced antrum formation and ensured normal mRNA expression for BMP receptor and Smads after IVC of caprine secondary follicles.  相似文献   
79.
This study aimed at assessing the effect of different concentrations of the growth factor similar to insulin 1 (IGF‐1) in the development, survival and ultrastructure of the bovine preantral follicles cultured in situ. Fragments of bovine ovarian cortical tissue were cultured during 1 and 7 days in 1 ml of α‐MEM+, supplemented with different concentrations of human recombinant IGF‐1 (0, 30, 70 and 100 ng/ml), in an incubator at 37°C and 5% of CO2 in 24‐well plates with total replacement of the medium every 2 days. Non‐cultured ovarian fragments (control) and ovarian fragments cultured during 1 and 7 days were processed for classic histology, mechanical isolation and electron transmission microscopy (ETM). Parameters such as normality, viability, activation, development, diameter and ultrastructure were evaluated. All statistical analyses were carried out using sas Version 9.2. The results showed that the percentage of follicles morphologically normal in the IGF‐1 30 ng/ml treatment was similar to the fresh control (p > 0.05) both on the day 1 and on the day 7 of in vitro culture. In the viability analysis, the cultured treatments maintained the percentage of viable follicles during the entire culture period (p > 0.05). After 7 days of culture, the IGF‐1 30 ng/ml treatment showed higher percentages of developing follicles (48.33%) than those of the fresh control (22.22%) and the cultured treatments (p < 0.05). Also, after 7 days of culture, IGF‐1 30 ng/ml presented a higher follicular diameter when compared to the control and other concentrations of IGF‐1 tested. Ultrastructurally, the non‐cultured control and IGF‐1 30 ng/ml, after 7 days of culture, showed conserved oocytes, nuclei and organelles. Hence, it is concluded that IGF‐1 30 ng/ml was the most efficient concentration for the development of bovine preantral follicles cultured in vitro.  相似文献   
80.
Metaflumizone is a novel sodium channel blocker insecticide   总被引:2,自引:0,他引:2  
Metaflumizone is a novel semicarbazone insecticide, derived chemically from the pyrazoline sodium channel blocker insecticides (SCBIs) discovered at Philips-Duphar in the early 1970s, but with greatly improved mammalian safety. This paper describes studies confirming that the insecticidal action of metaflumizone is due to the state-dependent blockage of sodium channels. Larvae of the moth Spodoptera eridania injected with metaflumizone became paralyzed, concomitant with blockage of all nerve activity. Furthermore, tonic firing of abdominal stretch receptor organs from Spodoptera frugiperda was blocked by metaflumizone applied in the bath, consistent with the block of voltage-dependent sodium channels. Studies on native sodium channels, in primary-cultured neurons isolated from the CNS of the larvae of the moth Manduca sexta and on Para/TipE sodium channels heterologously expressed in Xenopus (African clawed frog) oocytes, confirmed that metaflumizone blocks sodium channels by binding selectively to the slow-inactivated state, which is characteristic of the SCBIs. The results confirm that metaflumizone is a novel sodium channel blocker insecticide.  相似文献   
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