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1.
影响青海细毛羊早期性状非遗传因素的研究 总被引:1,自引:0,他引:1
以年度(YEAR)、场(HERD)、性别(SEX)、母亲年龄(DAGE)作为固定效应,应用方差分析方法,系统分析了2005~2010年间青海细毛羊早期性能记录。结果显示,年度、场对青海细毛羊早期性状均有显著影响,母羊年龄对初生重、断奶重、周岁剪毛前体重有显著影响,性别对初生重,断奶重,周岁剪毛前体重、周岁产毛量、羊毛长度、羊毛细度影响显著;所有性状均随母亲年龄的增加呈上升趋势,研究结果将为优化群体周转结构,建立青海细毛羊早期生产性状遗传评价模型提供科学依据,最终为该品种羊的早期选种奠定基础。 相似文献
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ANELISE REZENDE DE MORAES 《山东饲料》2013,(14):60-61
China has required a large quantity of commodities in order to keep with its economic growth path,driven by large exports,rapid urbanization and investment in fixed assets.Commodities exporter countries have benefited from China ’s immense"hunger"for commodities,especially during the 2000s.Brazil,for instance,has emerged in this scenario as one of the largest iron ore producers and exporters.However,the cooling down of the Chinese economy has brought doubts to the iron ore industry,which may remain strong in near future but one cannot claim for certain whether or not this trend will remain this positive in the long run. 相似文献
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Robyn S. HETEM Duncan MITCHELL Brenda A. DE WITT Linda G. FICK Shane K. MALONEY Leith C. R. MEYER Andrea FULLER 《Integrative zoology》2019,14(1):30-47
As one of the few felids that is predominantly diurnal, cheetahs (Acinonyx jubatus) can be exposed to high heat loads in their natural habitat. Little is known about long‐term patterns of body temperature and activity (including hunting) in cheetahs because long‐term concurrent measurements of body temperature and activity have never been reported for cheetahs, or, indeed, for any free‐living felid. We report here body temperature and locomotor activity measured with implanted data loggers over 7 months in 5 free‐living cheetahs in Namibia. Air temperature ranged from a maximum of 39 °C in summer to ?2 °C in winter. Cheetahs had higher (~0.4 °C) maximum 24‐h body temperatures, later acrophase (~1 h), with larger fluctuations in the range of the 24‐h body temperature rhythm (approximately 0.4 °C) during a hot‐dry period than during a cool‐dry period, but maintained homeothermy irrespective of the climatic conditions. As ambient temperatures increased, the cheetahs shifted from a diurnal to a crepuscular activity pattern, with reduced activity between 900 and 1500 hours and increased nocturnal activity. The timing of hunts followed the general pattern of activity; the cheetahs hunted when they were on the move. Cheetahs hunted if an opportunity presented itself; on occasion they hunted in the midday heat or in total darkness (new moon). Biologging revealed insights into cheetah biology that are not accessible by traditional observer‐based techniques. 相似文献
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R. DE COSTER A.-D. A. Y. DEGRYSE P. VAN DIJK L. A. A. OOMS E. LAGERWEIJ 《Journal of veterinary pharmacology and therapeutics》1987,10(3):227-232
R 8110, an imidazole derivative, was shown to be clinically superior to etomidate for induction and maintenance of anaesthesia in dogs. The present study compared the effects of intravenous (i.v.) R 8110, etomidate and Ringer solution on cortisol biosynthesis by the adrenal gland in seven male labradors. A tetracosactide challenge was carried out 30 min after the i.v. injection of 3 mg/kg of both drugs and after i.v. Ringer solution (1 ml/kg). Etomidate and R 8110 both suppressed the cortisol response to tetracosactide almost completely and increased the plasma 11 beta-deoxycortisol levels more than 20 fold. Maximal 11 beta-deoxycortisol values were reached 120 min after R 8110, and not less than 300 min after etomidate. Plasma 17 alpha-hydroxyprogesterone and testosterone concentrations did not differ between placebo and R 8110 treatment, but they decreased after etomidate. These results indicate that the effects of R 8110 on steroid biosynthesis in dogs are less pronounced than those of etomidate and are largely limited to a temporary inhibition of the 11 beta-hydroxylase in the adrenal gland. 相似文献
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ROSA NOVELLAS YVONNE ESPADA RAFAEL RUIZ DE GOPEGUI 《Veterinary radiology & ultrasound》2007,48(1):69-73
Resistive index (RI) and pulsatility index (PI) are indirect measurements of blood flow resistance that may be used to evaluate vascular changes in renal and ophthalmologic diseases. To our knowledge, no reports are available describing values for renal and ocular PI index in the unsedated dog and ocular RI and PI indices in the unsedated cat. The purpose of this study was to measure normal values for both intrarenal and ocular RI and PI within the same subject in unsedated clinically normal dogs and cats. Twenty-seven dogs and 10 cats were considered healthy by means of physical examination, CBC, biochemical profile, urinalysis, and ultrasonography. Systolic blood pressure was measured by Doppler ultrasonography. Intrarenal and ocular arteries were scanned by pulsed Doppler ultrasonography to calculate RI and PI. No significant differences were noted between the values obtained for the right vs. the left kidney and eye. The upper values of these indices were calculated as mean+2 standard deviations resulting in 0.72 and 1.52 for dog renal RI and PI; 0.7 and 1.29 for cat renal RI and PI; 0.76 and 1.68 for dog ocular RI and PI; and 0.72 and 1.02 for cat ocular RI and PI. 相似文献
7.
Irina GARCIA-ISPIERTO M. Angels ROSELLó Fabio DE RENSIS Fernando LóPEZ-GATIUS 《The Journal of reproduction and development》2013,59(6):544-548
This study compared the efficiency of a five-day or standard (nine-day)
progesterone-based regimen combined with equine chorionic gonadotrophin (eCG) in a
fixed-time AI (FTAI) protocol for dairy cows. The data examined were derived from
3577 inseminations conducted in three dairy herds. Animals with no estrus signs
detected over 21 days were randomly assigned to a PRID-9 or PRID-5 group. Cows in
each group received a progesterone intravaginal device (PRID) for 9 or 5 days,
respectively, PGF2α and eCG on PRID removal, and GnRH 48 h later.
Fixed-time AI was performed 12 h after the GnRH dose. Cows artificially inseminated
following spontaneous estrus during the study period were considered as controls.
Based on the odds ratio, the likelihoods of animals in PRID-9 in the warm (conception
rate [CR] of 22.3%) and cool (32% CR) periods, and control animals in the warm period
(26.6% CR) becoming pregnant were reduced (by factors of 0.6, 0.3 and 0.4,
respectively) compared with the control animals in the cool period (CR of 43.7%). The
risk of a twin pregnancy was higher (51.4%) for cystic PRID-9 cows (by a factor of
3.6) and lower (9.9%) for cyclic PRID-5 animals (by a factor of 0.4) compared with
the PRID-9 cyclic cows. These findings indicate that the proposed protocol achieves
similar results during the cool or warm season to those obtained when AI is conducted
at spontaneous estrus during the cool season. In addition, PRID-5 reduced twin
pregnancy compared with PRID-9. 相似文献
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