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81.
The study examined the effect of PIT tagging and size on the growth, survival, food conversion, tag retention and wound healing in juvenile European whitefish. Three size classes of juvenile whitefish (class S—body weight (b.w.) approx. 4.0 g; class M—b.w. approx. 8.0 g; class L—b.w. approx. 13.6 g) were tagged with PIT implanted intraperitoneally (TROVAN®, United Kingdom). These groups formed S‐P, M‐P and L‐P respectively. Fish from the control groups (groups S‐C, M‐C and L‐C) were not tagged. Whitefish from the tagged and control groups were reared for 28 days in recirculating aquaculture systems. Only in the fish from the smallest group (group S‐P) was tagging confirmed to have a negative impact on growth rate and survival, which, after 28 days, was 70% in comparison with 94.4% in group S‐C. The rate of wound healing in all whitefish groups was similar. After 28 days following PIT implantation, all wounds were healed. Short‐term PIT retention (28 days) for all the groups was > 90%, and no differences were noted among groups. In summary, it is recommended that whitefish be PIT‐tagged using the intraperitoneal method after they have attained a body weight > 8 g. Tagging smaller specimens of this species leads to higher mortality.  相似文献   
82.
The aim of this study was to determine the impact of MS‐222 on the haematological and biochemical parameters of juvenile pikeperch. The experiment was conducted on fish with body weight of 112.50 ± 13.01 g and body length of 22.5 ± 1.8 cm. The fish were exposed to MS‐222 via immersion at two concentrations (100, 150 mg/L) and for two exposure periods (3, 10 min). Significantly higher values of white blood cells, red blood cells, haemoglobin and haematocrit were noted in all groups of fish from which blood samples were drawn immediately after exposure. After 24 hr, only in group V (100/3/24) did the values of these parameters return to initial values. The analysis of biochemical parameters signalled significant differences in three parameters: glucose, total protein and lactates. Twenty‐four hours after exposure, the values of these three parameters returned to initial levels. Significant differences were also noted in four ion concentrations: potassium, phosphorus, sodium and iron. Twenty‐four hours later, potassium and phosphorus concentrations had returned to initial values, while that of sodium still exhibited significant differences. Twenty‐four hours later, differences were also noted in iron ion concentrations in the groups subjected to the longest exposure or the highest concentration. All of the MS‐222 immersion parameters were effective. However, the smallest changes in the analysed parameters of pikeperch blood were noted in individuals from group I (100/3/0). The current study indicated, however, that longer pikeperch immersion in the anaesthetic solution (>3 min) or applying concentrations exceeding 100 mg/L are not recommended.  相似文献   
83.
The aim of the present study was to evaluate the effects of three formulated diets: wheat gluten protein‐based diets supplemented with Lys–Gly dipeptide (PP) or free lisine and glycine (AA), and a control diet without lysine supplementation (CON), two commercial starters: Aller Futura (AF), Aglo Norse (AN) and frozen Chironomidae larvae (CH) for on the growth and digestive system development of rainbow trout. The experiment lasted 28 days and survival at the end of the experiment was the highest in the group fed AF (87.9±4.2%) and the lowest in the group fed the CON diet (74.0±4.3%). Fish fed the CON diet showed a significantly lower crude protein content, and the AA group had a significantly higher lipid level (P≤0.05) in body carcass compared with the other groups. The highest density of intestinal goblet cells (P≤0.05) was observed in fish fed the CON diet, while the lowest density was seen in the distal intestine in the AF group. The hepatocyte cytoplasm of all fish stored more glycogen than lipids. These results indicate that wheat gluten protein‐based diets supplemented with dipeptide Lys–Gly (PP) or free lysine and glycine (AA) supported growth, protein efficiency rate and intestine epithelium homeostasis. On the other hand, fish fed CON (lysine‐deficient diet) showed lower survival and growth rate, and disturbances of intestine epithelium homeostasis, probably as a result of lysine deficiency.  相似文献   
84.
We investigated in Syrian Golden hamsters the biological impact and its underlying mechanism of single whole grain breads supplemented with 2-3% hydroxypropyl methylcellulose (HPMC), a semisynthetic viscous soluble dietary fiber (SDF) as a substitute for gluten. Hamsters were fed high-fat diets supplemented with 48-65% (w/w) differently ground, freeze-dried single grain breads including whole grain wheat, barley, barley supplemented with HPMC, debranned oat, and oat supplemented with HPMC which were compared to a diet containing microcrystalline cellulose (control). All single grain breads significantly lowered plasma LDL-cholesterol concentrations compared to the control. Enrichment with HPMC further lowered plasma and hepatic cholesterol concentrations. Despite the reduced molecular weight of naturally occurring soluble (1--->3),(1--->4)-β-d-glucan (β-glucan) caused by the bread-making process, whole grain barley breads downregulated hepatic expression of CYP7A1 and HMG-CoAR genes that are responsible for bile acid and cholesterol synthesis, suggesting a possible role of bioactive compounds such as short-chain fatty acids and phenolic compounds from barley bread. Barley bread enriched with HPMC downregulated expression of ABCG5 gene. Taken together, it appears that distinctive modulation of synthesis and excretion of hepatic cholesterol and bile acid contributes to the cholesterol-lowering properties of whole grain barley breads and breads enriched with HPMC. These data suggests that alternative whole grain breads supplemented with HPMC may provide consumers with a staple food that can assist in cholesterol management.  相似文献   
85.
Weight-average molecular weight (Mw) and chain length of eight amylopectins isolated from one Australian, two United States, and five Korean wheats were measured using multiangle laser light scattering (MALLS) and refractive index (RI) detectors operated in a microbatch mode, and in a high-performance size-exclusion chromatography (HPSEC) mode. The Mw of amylopectins measured in the microbatch mode ranged from 29 × 106 to 349 × 106. Three amylopectins (Geuru, Tapdong and WW) showed significantly high Mw values over 200 × 106. The Mw measured by HPSEC mode with MALLS-RI detectors (42 × 106 to 73 × 106) were significantly less than those obtained in the microbatch mode with exception of dark northern spring hard wheat (DNS) amylopectin, indicating the possible variation of Mw by the analysis mode. Root-mean square of the radius of gyration (Rg) also was greater when the microbatch mode was used (122–340 vs. 95–116 nm). Chain length distributions of debranched amylopectins of different cultivars, measured by the HPSEC-MALLS-RI system, were similar. Weight average degrees of polymerization (DPw) of A, B1, and larger B chains (B≥2) had ranges of 13–22, 26–46, and 58–73, respectively, and mass ratios of A and B chains ranged from 0.7 to 1.1.  相似文献   
86.
The Russian sturgeon is a highly prized species reared in aquaculture. The process of gonad development in this critically endangered species is poorly understood. The aim of this study was to describe the localization of Sox9 protein during gonad development of the Russian sturgeon from the day of hatching to the 1440 day post hatching (dph). The larvae at age 1, 10, 25 dph and prepared gonads of 300, 720, 1440 dph individuals were immunohistochemistry‐stained for Sox9 detection. Sox9‐positive regions were detected in larvae in primordial germ cells cytoplasm. Analysis of 300 dph sturgeon gonads revealed the presence of the Sox9 protein in cytoplasm of some oocytes in the chromatin nucleus stage. In testes at 720 dph, Sox9 was observed in the cytoplasm of type A and early B spermatogonias. In the ovaries, Sox9 was observed in the cytoplasm of diplotene oocytes and prefollicular cells. In testes of 1440 dph sturgeon, Sox9 was present in the nucleus of the spermatocytes and in types A and B spermatogonias cytoplasm. Analysis of ovaries at 1440 dph reveals multiple diplotene oocytes with a Sox9‐positive cytoplasm. Furthermore, in 720 and 1440 dph, sturgeon presence of intersexual gonads was detected. In intersex gonads, Sox9 was observed in the cytoplasm of diplotene oocytes and type A spermatogonias. This study may be the first attempt to determine Sox9 protein localization during ontogenesis of the Russian sturgeon. Localization of Sox9 protein may become a useful marker of the maturation level in testis of the Russian sturgeon.  相似文献   
87.
Acute oak decline (AOD) is a syndrome affecting mature oak trees and is characterized by stem bleeds from vertical fissures on trunks, and inner bark necrosis caused by a polybacterial consortium, in which Gibbsiella quercinecans and Brenneria goodwinii, and to a lesser extent Rahnella victoriana and Lonsdalea britannica, play key roles. Here we report a novel multiplex real-time PCR assay that enables simultaneous and rapid detection and quantification of these four bacterial species from stem bleed swabs. Experiments with axenic cultures were performed to determine specificity and sensitivity of the multiplex quantitative PCR (qPCR). Whilst the primer/probe set for B. goodwinii was species-specific, primer/probe sets for the other three species were able to identify other members of their respective genera. There was no cross detection of genera within the multiplex qPCR, and non-target bacteria were not detected. The multiplex AOD assay had differential sensitivity for each bacterial species. The assay was evaluated on swab samples collected from stem bleeds of declining oak trees at a site in south-east England and was able to detect all four bacterial species. Absolute quantification of the bacteria from swab samples was possible through the inclusion of a standard curve prepared from dilutions of gene copy standards. This diagnostic tool will facilitate rapid detection of AOD-associated bacteria from samples that can easily be taken by non-specialists without specific training, and will also find application in other experimental work such as pathogenicity and control trials.  相似文献   
88.
Codling moth, Cydia pomonella (L.), is a cosmopolitan pest of apple, potentially causing severe damage to the fruit. Currently used methods of combating this insect do not warrant full success or are harmful to the environment. The use of plant-derived semiochemicals for manipulation with fruit-infesting behavior is one of the new avenues for controlling this pest. Here, we explore the potential of Ginkgo biloba and its synthetic metabolites for preventing apple feeding and infestation by neonate larvae of C. pomonella. Experiments with crude extracts indicated that deterrent constituents of ginkgo are present among alkylphenols, terpene trilactones, and flavonol glycosides. Further experiments with ginkgo synthetic metabolites of medical importance, ginkgolic acids, kaempferol, quercetin, isorhamnetin, ginkgolides, and bilobalide, indicated that three out of these chemicals have feeding deterrent properties. Ginkgolic acid 15:0 prevented fruit infestation at concentrations as low as 1 mg/mL, bilobalide had deterrent effects at 0.1 mg/mL and higher concentrations, and ginkgolide B at 10 mg/mL. On the other hand, kaempferol and quercetin promoted fruit infestation by codling moth neonates. Ginkgolic acids 13:0, 15:1, and 17:1, isorhamnetin, and ginkgolides A and C had no effects on fruit infestation-related behavior. Our research is the first report showing that ginkgo constituents influence fruit infestation behavior and have potential applications in fruit protection.  相似文献   
89.
European Journal of Plant Pathology - Pectobacterium parmentieri (former Pectobacterium wasabiae) is an emerging pectinolytic bacterial pathogen causing losses in potato (Solanum tuberosum L.)...  相似文献   
90.
Despite the great progress in the field of tendon injuries and chronic tendinopathies in recent years, treatment of these conditions is still challenging. Research utilising animal models is crucial for further advancement in tendon research, with the rabbit being a commonly used species in this field. The objective of the present study was to comprehensively describe the macro‐ and microanatomy of the common calcanean tendon (tendo Achillei), together with associated structures. Eight female New Zealand rabbits were subjected to anatomical dissection and histologic analysis, revealing significant species‐specific features. The soleus muscle presented a thin, spindle shape with no tendon of insertion and attached directly to the lateral gastrocnemius muscle. Therefore, it does not contribute to the formation of the common calcanean tendon. The calcaneal tendon of the semitendinosus muscle was identified as a strong tendinous band at the medial side of the medial gastrocnemius muscle and the superficial digital flexor muscle and tendon distally. The saphenous artery was accompanied by the medial saphenous vein and characteristic accessory medial saphenous vein. The complex structure of the paratendinous connective tissue is described, with the paratenon being contiguous with the epitenon of the individual tendons and epimysium of associated muscles. At the level of the calcaneal tuber, the retromalleolar fat pad was identified, adhering to the cranial surface of the conjoint gastrocnemius tendon. Histologic studies confirmed the presence of the subtendinous calcaneal bursa of superficial digital flexor tendon and the bursa of calcaneal tendon.  相似文献   
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