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981.
Humitake Seki Masayuki Takahashi Shun-Ei Ichimura 《Water, air, and soil pollution》1979,12(3):383-391
The heaviest algal bloom that can be expected in an aquatic system was formed in a waterchestnut ecosystem in Lake Kasumigaura during the summer in 1978 when the water temperature was greater than 30°C, caused by the nutrient discharges from the River Koise and the River Sanno. The heavy bloom not only threatens the steady-state equilibrium of the eutrophic system of the Lake but also must accelerate the Lake transformation into a low moor by forming ooze on the lake bottom with the precipitation of a large amount of dead blue-green algae. 相似文献
982.
Eunryel Nam Ayaka Takahashi Naoki Fujita Keiko Tsuzuki Ryohei Nishimura 《Veterinary ophthalmology》2013,16(4):263-268
Objective To develop and assess canine corneal epithelial cell sheets cultivated from limbal stem cells on amniotic membrane. Procedures Canine corneal limbal segments were obtained from six beagle dogs. Cryopreserved denuded amniotic membranes (obtained from Miniature Dachshund and Cavalier King Charles Spaniel breeds) from which the epithelial cells were removed were used as scaffolds. The limbal segments were cultured on these amniotic membranes with 3T3 feeder cells for 2 weeks. The harvested corneal epithelial cell sheets were stained with H&E for histologic analysis. The harvested sheets were analyzed immunohistochemically using a corneal epithelium‐specific marker keratin 3(K3) and putative stem cell markers ABCG2, p63, and vimentin. Results Cultivated cells from the corneal limbal tissues reached confluency in 7–8 days. The cultivated cells adhered to the denuded amniotic membrane and formed a sheet. The cultivated cell sheet was transparent and consisted of five to eight layers. K3 was observed in all layers and ABCG2, p63, and vimentin were notably present in the basal layer of the cultivated canine epithelium by immunofluorescence. Conclusions Canine corneal epithelial cells were successfully cultivated on the canine amniotic membrane. The cultivated epithelial sheets contained putative stem cells in the basal layer and had a stratified epithelium. 相似文献
983.
Takahashi Y Tojo T Nagahora S Yamazaki K 《Journal of agricultural and food chemistry》2007,55(8):2923-2929
This paper reports a simple, low-cost, and extremely sensitive reporter-gene assay system for comprehensive analysis of estrogenic activity using transgenic Arabidopsis thaliana: the EPTH system. It had the capability to detect 17beta-estradiol at a concentration of 10 pM. The system was rendered 5 times more sensitive than a previous system [Tojo, T.; Tsuda, K.; Wada, T.; Yamazaki, K. Ecotoxicol. Environ. Saf. 2006, 64, 106-114) (1)] by increasing the copy number of the transactivation domain fused to a nuclear receptor co-activator. The system can efficiently detect other estrogenic and antiestrogenic substances. Estrogenic activities were determined in treated sewage samples from four distinct sewage farms using the system. Results showed that the system can detect estrogenic activity directly and more efficiently than a yeast two-hybrid system without any manipulation for extraction and condensation of hydrophobic compounds and aseptic treatment. Furthermore, the system also is useful as a powerful tool for discovery of a new category of natural estrogenic substances that are undetectable by previous plant and yeast systems. 相似文献
984.
T. Sako A. Mori P. Lee T. Sato H. Mizutani T. Takahashi Y. Kiyosawa H. Tazaki T. Arai 《Veterinary research communications》2009,33(5):473-479
Measurements of serum fructosamine, glycated hemoglobin, and glycated albumin (GA) complement serum glucose concentration
for better management of diabetes mellitus (DM). Especially, the serum fructosamine test has long been used for diagnosing
and monitoring the effect of treatment of DM in dogs. However, fructosamine tests are currently not performed in veterinary
medicine in Japan. GA and fructoasmine levels have been shown to strongly correlate. However, the clinical implications of
using GA remain to be elucidated. Therefore, the purpose of the current study was threefold: 1) Determine whether GA% is altered
by acute hyperglycemia in normal dogs, simulating stress induced hyperglycemia; 2) Demonstrate that GA% does not dynamically
change with diurnal variation of blood glucose concentration in diabetic dogs; and 3) Investigate whether GA% is capable of
providing an index of glycemic control for 1–3 weeks in diabetic dogs as is the case with diabetic human patients. Our study
demonstrated that serum GA% remains very stable and unaltered under acute hyperglycemic conditions (intravenous glucose injection)
and in spite of diurnal variation of blood glucose concentration. Furthermore, serum GA% can reflect long-term changes (almost
1–3 weeks) in blood glucose concentration and the effect of injected insulin in diabetic dogs. 相似文献
985.
H. Takahashi Y. Kurose Y. Suzuki M. Kojima T. Yamaguchi Y. Yoshida M. Ogino K. Hodate Y. Azuma T. Sugino M. Kojima K. Kangawa Y. Hasegawa S. Kobayashi 《Domestic animal endocrinology》2009
The effect of energy balance on the growth hormone (GH) secretory responsiveness to growth hormone-releasing hormone (GHRH) has not been determined in ruminant animals. Therefore, we examined the effects of intravenous injections of 0, 3.3, and 6.6 μg ghrelin/kg body weight (BW), with and without GHRH at 0.25 μg/kg BW, on GH secretory responsiveness in both the fed and fasted sheep. The injections were carried out at 48 h (Fasting state) and 3 h (Satiety state) after feeding. Blood samples were taken every 10 minutes, from 30 minutes before to 120 minutes after the injection. Low (3.3 μg/kg BW) and high (6.6 μg/kg BW) doses of ghrelin stimulated GH secretion significantly (P < .05) greater in the Satiety state than in the Fasting state. Growth hormone-releasing hormone plus both doses of ghrelin stimulated GH secretion significantly (P < .05) greater in the Satiety state than in the Fasting state. Ghrelin and GHRH exerted a synergistic effect in the Satiety state, but not in the Fasting state. Plasma ghrelin levels were maintained significantly (P < .05) greater in the Fasting state than in the Satiety state except the temporal increases after ghrelin administration. Plasma free fatty acid (FFA) concentrations were significantly (P < .01) greater in the Fasting state than in the Satiety state. In conclusion, the present study has demonstrated for the first time that ghrelin differentially modulates GH secretory response to GHRH according to feeding states in ruminant animals. 相似文献
986.
987.
Sato T Kamiyama T Takahashi T Kurahashi K Yamada K 《Science (New York, N.Y.)》2001,291(5508):1517-1519
High-resolution angle-resolved photoemission spectroscopy of the electron-doped high-temperature superconductor Nd(2-x)Ce(x)CuO4 (x = 0.15, transition temperature T(c) = 22 K) has found the quasiparticle signature as well as the anisotropic d(x2-y2)-like superconducting gap. The spectral line shape at the superconducting state shows a strong anisotropic nature of the many-body interaction. The result suggests that the electron-hole symmetry is present in the high-temperature superconductors. 相似文献
988.
There is no doubt that the life cycle of crop plants depends on two fundamental metabolic processes: photosynthesis and nutrient absorption. When these two important functions are considered in connection with morphology of crops, we can easily find out the differentiation of functions, that is, photosynthesis by green leaves and nutrient absorption by roots. In the past, a number of investigations have been made on these two functions of rice plants, the physiology of their leaves as photosynthetic organ has also been studied in detail. On the physiology of roots, however, knowledge which we have today is not as detailed as is deemed necessary. 相似文献
989.
In the previous paper1), we compared the in. organic composition of root with that of shoot of rice plant at successive growth stages, and revealed that the content of inorganic elements in root was generally lower than that in shoot, and that paddy root, sending most of absorbed salts to the top, does not possess a function to store inorganic nutrients. 相似文献
990.
In the previous studies we investigated some characteristics of paddy root in comparison with shoot by analysis of inorganic elements1) and metabolizable forms of organic compounds2) of shoot and root at successive growth stages, and found that the contents of the above-mentioned components in root were generally lower than those in shoot with few exceptions. From this it is concluded that in root the contents of the residual components, mainly cell wall substances, must be high. To ascertain this surmise, we carried out analysis of shoot, root and inflorescences of rice plant with respect to hemicellulose, cellulose and lignin which construct cell walls. 相似文献