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101.
Interspecific hybridization is an effective method to generate a new crop that gains available functions in a short time. Interspecific hybrids (2n= 16) betweenAllium fistulosumL. (2n= 16) andAllium schoenoprasumL. (2n= 16) were produced by reciprocal crossings through ovary culture, but the hybrids were much fewer in the combination usingA. schoenoprasumas a seed plant. All the hybrids have eight long chromosomes originated fromA.fistulosumand eight short chromosomes originated fromA. schoenoprasum. In addition, the hybridity was confirmed by randomly amplified polymorphic DNA (RAPD) analysis and cleaved amplified polymorphic sequence (CAPS) analysis of the rDNA internal transcribed spacer (ITS) region. The interspecific hybrids showed a vigorous growth habit; their foliage was slightly bloomy and deep green. The hybrids did not form bulbs, but rather propagated vegetatively by tillering. Carotene contents of the hybrids and both parents were quantified using high-performance liquid chromatography (HPLC). The contents of all edible parts of the hybrids were approximately seven times higher than those of either parent. These results indicate that the hybrid is a new and carotene-rich vegetable ofAlliumspecies.  相似文献   
102.
Ferulic and p‐coumaric acids were analyzed in 50 rice (Oryza sativa L.) samples from 32 cultivars harvested in Japan. In brown rice, ferulic and p‐coumaric acid levels ranged from 309 to 607 mg/kg and from 49 to 100 mg/kg, respectively. In 70% polished rice, ferulic and p‐coumaric acid levels ranged from 27 to 103 mg/kg and from 0.4 to 3.5 mg/kg, respectively. Ratios of average phenolic acid levels in the 70% polished rice to the brown rice were 13.9% for ferulic acid and 1.9% for p‐coumaric acid. The ferulic acid level was highly correlated between brown and 70% polished rice (R = 0.815; P < 0.01), but there was no clear correlation for p‐coumaric acid. Phenolic acid levels in the 70% polished rice did not show any clear correlations between the analytical index measurements for sake brewing suitability (weight of 1,000 grains, water absorption, digestibility, crude protein, and potassium content). Phenolic acid levels in the 70% polished rice directly affected levels in the rice koji enzyme digest. The results indicated that phenolic acid levels in sake were affected by the levels in ingredient rice grains, which may then influence the sensory quality of sake.  相似文献   
103.
ABSTRACT:   To study the adaptability of juvenile fugu Takifugu rubripes to low-salinity environments, fish were transferred from full-strength seawater (100% SW) to freshwater (FW) and 25, 50, 75 and 100% SW, and checked for mortality over 3 days. No mortality was observed in 25–100% SW, whereas all fish died in FW. In fish transferred to 25–100% SW, blood osmolality was maintained within a physiological range. To further explore the lower limit of salinity that fugu could tolerate, fish were transferred from 100% SW to FW and 1, 5, 10, 15 and 25% SW. All fish survived in 5–25% SW, but fish died in FW and 1% SW. In fish surviving transfer to FW and 1 and 5% SW, blood osmolality was decreased to a near sublethal level of approximately 300 mOsm/kg·H2O. Therefore, the lower limit of salinity tolerance is estimated to lie between 5 and 10% SW. Preacclimation in 25% SW for 7 days did not essentially affect the survival salinity range. Although survival rates and blood osmolality were slightly improved by preacclimation in 25% SW, blood osmolality was markedly decreased in salinities less than 10% SW, as was seen in the direct transfer. Neither chloride cell morphology nor sodium-potassium adenosinetriphosphatase activity in the gills showed a significant change following transfer to low salinities. These findings indicate that fugu can be adapted to hypoosmotic environments to some extent, exerting hyperosmoregulatory ability, although chloride cells are less likely to absorb ions in hypoosmotic environments.  相似文献   
104.
1,5-anhydro-D-glucitol (1,5AG) is a pyranoid polyol compound found in human circulating blood. Myo-inositol (MI) is a stereoisomer of inositol and serves as a precursor of inositol phospholipids. 1,5AG and MI are filtered by the glomerulus and almost completely reabsorbed through the renal tubules. However, under hyperglycemic conditions, reabsorption through the renal tubules is competitively inhibited because the structures of 1,5AG and MI resemble that of glucose. In this study, we investigated the kinetics of serum and urine 1,5AG and MI levels in healthy dogs. We demonstrated that 1,5AG and MI exist in canine serum and urine by gas chromatography-mass spectrometry. Under continuous hyperglycemic conditions, the serum 1,5AG concentration in healthy dogs decreased while the serum MI concentration remained unchanged. Urinary excretion of 1,5AG and MI increased significantly after blood glucose concentrations reached 200 to 220 mg/dl. A significant negative correlation was observed between serum 1,5AG and glucose concentrations during hyperglycemia. However, no significant correlation was observed between serum MI and glucose concentrations. In this study, we demonstrated that serum and urine 1,5AG and MI levels were changed by blood glucose concentrations. The serum 1,5AG concentration was decreased by continuous hyperglycemia. However, the serum MI concentration does not reflect hyperglycemia.  相似文献   
105.
Pancreatitis is a common exocrine pancreatic disease in dogs, and the pancreatic lipase immunoreactivity (PLI) test is used for diagnosis. Enzyme catalytic assay is thought to have low specificity, but a lipase activity assay with increased specificity has been developed in human clinical chemistry. We measured serum lipase activity of 65 client-owned dogs using the newly developed FUJI DRI-CHEM slide and compared the results with their PLI concentrations. The results showed a good correlation (r = 0.91), and the normal and pancreatitis dogs identified based on the PLI values were correctly separated based on lipase activity. The present study suggests that FUJI DRI-CHEM lipase activity would be helpful for diagnosis of pacreatitis in dogs and, in particular, that it can be used as a patient-side assay and contributes to immediate treatment.  相似文献   
106.
Intracytoplasmic sperm injection (ICSI)-mediated gene transfer has recently been shown to be an effective technique for producing transgenic pigs; however, the types of sperm pretreatment having the most beneficial effects on post-ICSI embryogenesis or transgenic efficiency have not been clarified. In the present study, we performed ICSI-mediated gene transfer using pig sperm subjected to various pretreatments and determined the developmental potential of sperm-injected oocytes and introduction efficiency of exogenous DNA. Embryos were then transferred to recipient pigs to confirm gene transfer efficiency during the fetal period. When ICSI was performed using unfrozen sperm heads with tails removed by piezo-pulse, the rates of blastocyst formation (14.2%, 17/120) and transgene (EGFP) expression (11.8%, 2/17) were both low. When unfrozen sperm heads were used that were removed by sonication, EGFP expression efficiency (11/21, 52.4%) improved significantly (P<0.05). Pretreatment of unfrozen sperm with a surfactant or acrosomal reaction did not further improve the rates of blastocyst formation and EGFP expression. However, use of the heads of sperm frozen-thawed with or without a cryoprotective agent resulted in rates of blastocyst formation and EGFP expression that tended to be generally high (23.0%, 14/61-33.8%, 26/77 and 42.9%, 6/14-66.7%, 10/15). A total of 219 in vitro matured oocytes were fertilized by ICSI-mediated gene transfer using the heads of frozen-thawed sperm and then transferred into two recipient pigs. Seven fetuses were obtained, and EGFP expression and integration of the transgene (10-30 copies) were confirmed in two of the seven fetuses. Use of unfrozen sperm thus confers no advantages on ICSI-mediated gene transfer, and although further investigations are needed, frozen-thawed sperm heads appear to be useful in ICSI-mediated gene transfer.  相似文献   
107.
The aim of this study was to examine the impact of zona pellucida damage, which might arise during somatic cell nuclear transfer (SCNT), on the development and survival of transferred embryos. The zonae pellucidae of in vitro matured oocytes were either punctured with 8- to 10-microm square-ended nuclear injection pipettes and piezo pulses or slit with 35- to 40-microm enucleation pipettes. Intact oocytes were used as controls. These oocytes were electroactivated to induce parthenogenesis and transferred to the oviducts of estrus-synchronized recipient gilts. After 5 to 7 days, the recipient uteri were flushed to collect embryos, and embryonic development (morula-blastocyst stage embryos/collected embryos) and survival (viable embryos/collected embryos) were determined. In total, 221 zona-punctured, 129 zona-slitted and 57 intact embryos were transplanted into four, two and two gilts, respectively. The efficiency of embryo recovery was similar in all groups (64.3 to 79.1%). However, the zona-penetrated and incised embryos exhibited unstable development and survival compared with the controls; development and survival of the control embryos were 94.7 and 87.7%, whereas those of the zona-punctured embryos were 69.0 and 47.9% (P<0.01) and those of the zona-slit embryos were 64.7 and 50.0% (P<0.01). Cells with large foci that appeared to be macrophage giant cells were observed at the surface or inside the degenerated zona-damaged embryos. These results indicate that the recipient's immune response to damage to the zona pellucida may impair embryonic development after transplantation to the oviduct. This may be one of the factors causing the reduced efficiency of live progeny production by SCNT.  相似文献   
108.
A noble approach for the estimation of the deposition of the Asian dust over Japan by using atmospheric anthropogenic radioactivity, 90Sr and 137Cs, is proposed. Those radioactivities once deposited globally onto the ground by the past nuclear test, etc. are resuspended along with the surface soil particles in the air by the storm and deposited again on the ground. The difference in 137Cs/90Sr activity ratios in the surface soil between dry and wet climatic conditions gives a clue to know about the source of the dust. It was found that the average activity ratio in the deposited material (average: 2.1, n=82) at MRI, Tsukuba in the 1990s is not close to that of the surface soil taken in neighborhood (median: 6.8, n=8), which had been considered as the primary source. While, it is close to that of the soil samples taken in the arid area in the Asian continent (median: 2.0, n=4), which is the one of the source regions of the aeolian dust. Thus we can reasonably assume that deposited dust in Tsukuba is brought not only from the neighboring fields, etc. but also from the arid area in the continent. Using a simple two-component model it was estimated that the Asian dust may transport about 90% of 90Sr and 70% of 137Cs depositions observed in Tsukuba in the 1990s. Also, Asian dust may transport about 2/3 of the dust deposited in Tsukuba.  相似文献   
109.
To clarify the direct effects of Ghrelin on growth hormone (GH) release from anterior pituitary (AP) cells in pigs, GH-releasing effects of human Ghrelin (hGhrelin) and rat Ghrelin (rGhrelin) on porcine AP cells were compared with GHRH in vitro. The AP cells were obtained from 6-month-old pigs and the cells (2 x 10(5) cells per well) were incubated for 2 h with the peptides after incubating in DMEM for 3 days. hGhrelin and rGhrelin significantly stimulated GH release from the cultured cells at doses of 10(-8) and 10(-7)M (P < 0.05). The rates of increase in GH at 10(-8) and 10(-7)M of hGhrelin were 82.7 and 131.9%, while those with rGhrelin were 43.9 and 79.5%, respectively. GHRH significantly stimulated GH release from the cells at a dose as low as 10(-11)M (P < 0.05), and the response to GHRH was greater than that induced by Ghrelins. In time-course experiments, GHRH continued to increase GH concentrations in media until 120 min after incubation; however, those in media treated with hGhrelin reached a plateau 60 min after incubation, and the maximal value was approximately one third that obtained with GHRH. When hGhrelin (10(-8)M) and GHRH (10(-8)M) were added together, additive effects of both peptides on the release of GH were observed (P < 0.05). Somatostatin (SS, 10(-7)M) significantly blunted GH release induced by hGhrelin (10(-8)M) and GHRH (10(-8)M) (P < 0.05). In the presence of SS, additive effects of hGhrelin and GHRH on the release of GH were observed (P < 0.05). These results show that Ghrelin directly stimulates GH release from anterior pituitary cells in pigs; however, the GH-releasing effect is weaker than that of GHRH in vitro. The present results also show that Ghrelin interacts with GHRH and SS to in the release of GH from porcine adenohypophysial cells.  相似文献   
110.
The objective of this study was to characterize plasma insulin-like growth factor-I (IGF-I) profiles during the estrous cycle in goats. Frequent blood samples were drawn during the day of estrus and during the luteal phase on Day 10 after estrus, and plasma growth hormone (GH) and IGF-I profiles were examined. Then, daily blood samples were drawn throughout the estrous cycle or during induction of estrus by prostaglandin F(2alpha) (PGF(2alpha)) to further clarify the IGF-I profiles. GH was secreted in an episodic manner in the estrous and luteal phases in goats. There were no significant differences in the mean concentrations, pulse amplitude and pulse frequency of GH between the estrous and luteal phases. IGF-I concentrations during estrous phase were higher than those in the luteal phase (P<0.05). Plasma IGF-I increased approximately two days before behavioral estrus, and the IGF-I peak was observed in accordance with the appearance of estrus. The elevated IGF-I levels then declined to basal values 4 to 5 days after estrus. When estrus was induced by PGF(2alpha), plasma IGF-I concentrations increased after treatment, and the concentration 2 days after treatment (day of appearance of behavioral estrus) was significantly higher than concentrations before treatment (P<0.05). The elevated IGF-I levels then declined during the 3 days after treatment. These results indicate that plasma IGF-I concentrations increase during estrus in goats.  相似文献   
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