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91.
V. P. Kalinichenko V. K. Sharshak O. S. Bezuglova E. P. Ladan E. D. Genev V. V. Illarionov V. E. Zinchenko N. A. Morkovskoi V. V. Chernenko L. P. Il’ina 《Eurasian Soil Science》2011,44(8):927-938
Changes in the properties of solonetzic soil associations (chestnut solonetzic soils and chestnut solonetzes) in the dry steppe
after their reclamation have been studied for 30 years. The reclamation included the deep three-tier plowing and the approach
of rotary tillage. A single rotary tillage operation resulted in the formation of fine aggregates of equal sizes in the plow
layer; any morphological features of the restoration of solonetzic pedogenesis are absent. The atmospheric moisture easily
penetrates into the soil, and soluble salts are leached off to a great depth. In 30 years since the soil amelioration with
the use of a PMS-70 rotary tiller, the humus content has increased up to 3.3% in the upper 20-cm-thick layer and up to 2.4%
in the layer of 20–40 cm. The content of adsorbed Na+ in the 20- to 30-cm-thick layer has decreased to 10.6% of the cation exchange capacity (in comparison with 19.8% in the nonreclaimed
soil). The spatial heterogeneity of the soil cover has decreased in comparison with that prior to the reclamation. During
the entire observation period, crop yields gained from the fields reclaimed with the use of the rotary tiller have been by
25–60% higher in comparison with those on the fields with traditional treatments. 相似文献
92.
Sorption by soil organic matter (SOM) is considered the most important process affecting the bioavailability of hydrophobic organic chemicals (HOCs)in soil.The sorption capacity of SOM for HOCs is affected by many environmental factors.In this study,we investigated the effects of soil pH and water saturation level on HOC sorption capacity of SOM using batch sorption experiments.Values of soil organic carbon-water partition coefficient (KOC) of six selected polycyclic aromatic hydrocar... 相似文献
93.
Shuai ZHANG Xin WU Dandan HAN Yong HOU Jianzhuang TAN Sung Woo KIM Defa LI Yulong YIN Junjun WANG 《农业科学与工程前沿(英文版)》2021,8(1):15
94.
Soil heterotrophic respiration and its temperature sensitivity are affected by various climatic and environmental factors.However,little is known about the combined effects of concurrent climatic and environmental changes,such as climatic warming,changing precipitation regimes,and increasing nitrogen(N)deposition.Therefore,in this study,we investigated the individual and combined effects of warming,wetting,and N addition on soil heterotrophic respiration and temperature sensitivity.We incubated soils collected from a temperate forest in South Korea for 60 d at two temperature levels(15 and 20℃,representing the annual mean temperature of the study site and 5℃warming,respectively),three moisture levels(10%,28%,and 50%water-filled pore space(WFPS),representing dry,moist,and wet conditions,respectively),and two N levels(without N and with N addition equivalent to 50 kg N ha-1year-1).On day 30,soils were distributed across five different temperatures(10,15,20,25,and 30℃)for 24 h to determine short-term changes in temperature sensitivity(Q10,change in respiration with 10℃increase in temperature)of soil heterotrophic respiration.After completing the incubation on day 60,we measured substrate-induced respiration(SIR)by adding six labile substrates to the three types of treatments.Wetting treatment(increase from 28%to 50%WFPS)reduced SIR by 40.8%(3.77 to 2.23μg CO2-C g-1h-1),but warming(increase from 15 to 20℃)and N addition increased SIR by 47.7%(3.77 to 5.57μg CO2-C g-1h-1)and 42.0%(3.77 to 5.35μg CO2-C g-1h-1),respectively.A combination of any two treatments did not affect SIR,but the combination of three treatments reduced SIR by 42.4%(3.70 to 2.20μg CO2-C g-1h-1).Wetting treatment increased Q10by 25.0%(2.4 to 3.0).However,warming and N addition reduced Q10by 37.5%(2.4 to 1.5)and 16.7%(2.4 to 2.0),respectively.Warming coupled with wetting did not significantly change Q10,while warming coupled with N addition reduced Q10by 33.3%(2.4 to 1.6).The combination of three treatments increased Q10by 12.5%(2.4 to 2.7).Our results demonstrated that among the three factors,soil moisture is the most important one controlling SIR and Q10.The results suggest that the effect of warming on SIR and Q10can be modified significantly by rainfall variability and elevated N availability.Therefore,this study emphasizes that concurrent climatic and environmental changes,such as increasing rainfall variability and N deposition,should be considered when predicting changes induced by warming in soil respiration and its temperature sensitivity. 相似文献
95.
Poly(ethylene terephthalate) fabrics were metallized through electroless plating of copper. The copper plating was performed
on palladium-decorated polyaniline surfaces, and polyaniline was present as an intermediate layer on fabrics to facilitate
palladium formation. Different oxidation states of polyaniline were tested in their efficacy in Pd (II) reduction and subsequent
Cu plating. X-ray photoelectron spectroscopy was used to monitor the surface changes along the metallization procedure, and
surface resistance was measure to probe the electrical properties of the metallized fabrics. 相似文献
96.
Jiyoung PARK Aryung NAM Hae-Beom LEE Seong Mok JEONG Dae-Hyun KIM 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2022,84(6):799
A 10-year-old intact male Shih Tzu dog presented with hematuria. Double-contrast cystography revealed a polypoid filling defect at the apex of the urinary bladder. Ultrasonography revealed a heterogeneously hypoechoic intramural mass with minimal vascular flow beneath the submucosal layer. After partial cystectomy, a well-demarcated bladder leiomyosarcoma was diagnosed on histopathology. The patient was alive and well without any clinical signs, recurrence, or metastasis at the 29-month follow-up after the surgical removal of the bladder mass. Leiomyosarcoma should be considered as a differential diagnosis if mass-like lesions are observed in the urinary bladder, although this type of malignancy is rare in canines. Histopathological confirmation is important for predicting prognosis and determining further medical plans. 相似文献
97.
Sang Tae Shin Sung Keun Jang Hong Suk Yang Ok Keun Lee Yhong Hee Shim Won Il Choi Doo Soo Lee Gwan Sun Lee Jong Ki Cho Young Won Lee 《Journal of veterinary science (Suw?n-si, Korea)》2008,9(1):103-107
This study was performed to produce transgenic Korean native goat (Capra hircus) by laparoscopic embryo transfer (ET) to overcome the limitations of ET performed by laparotomy. Transgenic embryos were produced by DNA pronuclear microinjection of in vivo zygotes. The recipient goats were synchronized for estrus by using an introvaginal progesterone devices as a controlled internal drug-releasing insert (CIDR) for 13 days and injection of 400 IU PMSG 48 h before removal of the insert. Embryos were transferred on day 3 and 4 after removal of the insert. Recipient goats were deprived of feed for 48 h, then suspended in a laparotomy cradle at an angle of 45°. After obtaining a sufficient pneumoperitoneum, the laparoscope and forceps were inserted abdominally through 5 mm trocar sleeves. Examination of the ovaries and uterus was performed and then 213 embryos were transferred into the oviducts via the infundibula of 76 recipient goats. To compare pregnancy rates, ET was also performed by laparotomy in 82 recipient goats. The pregnancies in the recipient goats were diagnosed by ultrasound on day 30 after embryo transfer. The pregnancy rate with laparoscopic ET was significantly higher than with ET performed by laparotomy (46.1% vs. 28.6%, p < 0.05). In addition, the pregnancy rates were compared between ovulated and non-ovulated ovaries of the recipient goats in the laparoscopic ET group. No significant difference was observed between the pregnancy rates of ovulated and non-ovulated ovaries (41.3% vs. 33.3%, p < 0.05) suggesting that ET may also be possible in non-ovulated recipients through artificial rupture of Graafian follicles. These results suggest that laparoscopic ET is a highly efficient method for the transfer of goat embryos. 相似文献
98.
Jin Ho CHO Ying Jie CHEN Byung Joon MIN Jong Sang YOO Yuan WANG In Ho KIM 《Animal Science Journal》2008,79(4):453-459
Two experiments were conducted to investigate the effects of reducing dietary crude protein on growth performance, odor gas emission from manure and blood urea nitrogen and IGF-1 concentrations of serum in nursery pigs. In experiment 1, the dietary treatments were (i) CON (CP 19.5%) and (ii) T1 (CP 16.0%). In feces samples, NH3 , H2 S, acetic acid and butyric acid emissions during the T1 treatment were lower than during the CON treatment ( P < 0.05). In feces-urine samples, NH3 emission during the T1 treatment was lower than during the CON treatment ( P < 0.05). In experiment 2, 28 crossbred (Landrace × Yorkshire × Duroc) pigs (13.58 ± 0.10 kg) were used for a 42-day growth trial. Throughout the entire experimental period, ADG and ADFI of the CON treatment were higher than the T1 treatment ( P < 0.05). On day 14, N digestibility in pigs fed the CON diet was higher than that of pigs fed the T1 diet ( P < 0.05). On days 28 and 42, DM digestibility of the CON diet was greater than the T1 treatment ( P < 0.05). On dat 42, serum BUN concentration of pigs fed the CON diet was higher than that of pigs fed the T1 diet ( P < 0.05). In conclusion, these results indicate that reduction in dietary CP concentration decreased NH3 , H2 S and VFA emissions in feces and growth performance in nursery pigs. 相似文献
99.
Summary. Field and glasshouse experiments demonstrated (hat 2,3,5-trichloro-4- pyridinol (pyriclor) at 50–500 g/ha controls Echinochloa crusgalli in direct-seeded rice. It prevented germination and restricted growth of the weed under both static and percolating water conditions, but allowed rice to germinate and grow normally. Pyriclor was most effective when applied early; treated plots gave higher yields than those hand-weeded or sprayed with propanil. Grass weed control was as effective as that given by molinate or nitrofen at much higher rates. Dichlobenil inhibited rice germination, was toxic to young seedlings, and is therefore unsuitable for direct-seeded rice. Molinate had a wider range of latitude in time of application than the other chemicals tested. Glasshouse experiments indicated that pyriclor moves down in percolating water but is adsorbed more readily in fine than in coarse-textured soils. 相似文献
100.
KI‐DONG EOM CHAE‐YOUNG LIM SU‐HYUN GU BYEONG‐TECK KANG YOUNG‐BO KIM DONG‐PYO JANG EUNG‐JE WOO DAEYOUNG KIM ZANG‐HEE CHO HEE‐MYUNG PARK 《Veterinary radiology & ultrasound》2008,49(6):595-599
A Yorkshire terrier and a Chihuahua were referred for acute onset, generalized tonic‐clonic seizures and were suspected to have meningoencephalitis based on magnetic resonance (MR) imaging findings. Brain lesions appeared hyperintense with T2‐weighted imaging and hypointense with T1‐weighted imaging, and were characteristic of necrotizing meningoencephalitis. Both dogs were diagnosed with necrotizing meningoencephalitis based on pathologic findings. Fluorine‐18 fluorodeoxyglucose positron emission tomography (FDG‐PET) was performed on both animals before euthanasia with the permission of the owner. In FDG‐PET images, these lesions seen in MR images were characterized by multifocal or diffuse hypometabolism. Our FDG‐PET results provided evidence of glucose hypometabolism in areas of necrosis and cavitation associated with necrotizing meningoencephalitis. FDG‐PET has the potential to provide valuable diagnostic information in dogs with suspected necrotizing encephalitis. 相似文献