全文获取类型
收费全文 | 176篇 |
免费 | 10篇 |
专业分类
林业 | 20篇 |
农学 | 19篇 |
基础科学 | 8篇 |
19篇 | |
综合类 | 5篇 |
农作物 | 28篇 |
水产渔业 | 2篇 |
畜牧兽医 | 72篇 |
园艺 | 4篇 |
植物保护 | 9篇 |
出版年
2023年 | 1篇 |
2022年 | 4篇 |
2021年 | 2篇 |
2020年 | 5篇 |
2019年 | 6篇 |
2018年 | 6篇 |
2017年 | 5篇 |
2016年 | 6篇 |
2015年 | 6篇 |
2014年 | 4篇 |
2013年 | 17篇 |
2012年 | 10篇 |
2011年 | 12篇 |
2010年 | 11篇 |
2009年 | 3篇 |
2008年 | 5篇 |
2007年 | 5篇 |
2006年 | 2篇 |
2005年 | 2篇 |
2004年 | 1篇 |
2003年 | 4篇 |
2002年 | 3篇 |
2001年 | 1篇 |
2000年 | 2篇 |
1999年 | 2篇 |
1997年 | 3篇 |
1996年 | 3篇 |
1995年 | 2篇 |
1994年 | 1篇 |
1993年 | 3篇 |
1992年 | 7篇 |
1991年 | 5篇 |
1990年 | 5篇 |
1989年 | 8篇 |
1988年 | 5篇 |
1987年 | 3篇 |
1979年 | 2篇 |
1976年 | 1篇 |
1975年 | 1篇 |
1974年 | 1篇 |
1973年 | 2篇 |
1972年 | 2篇 |
1971年 | 1篇 |
1970年 | 1篇 |
1969年 | 2篇 |
1968年 | 1篇 |
1967年 | 1篇 |
1958年 | 1篇 |
排序方式: 共有186条查询结果,搜索用时 15 毫秒
71.
MK Singh KP Singh D Kumar RA Shah T Anand MS Chauhan RS Manik SK Singla P Palta 《Reproduction in domestic animals》2013,48(2):284-291
When buffalo embryonic stem (ES) cell–like cells that expressed surface markers SSEA‐4, TRA‐1‐60, TRA‐1‐81, CD9 and CD90 and intracellular markers OCT4, SOX2 and FOXD3, as shown by immunofluorescence, and that expressed REX‐1 and NUCLEOSTEMIN as confirmed by RT‐PCR, were subjected to suspension culture in hanging drops in absence of LIF and buffalo foetal fibroblast feeder layer support, they differentiated to form three‐dimensional embryoid bodies (EBs). Of 231 EBs examined on Day 3 of suspension culture, 141 (61.3 ± 3.09%) were of compact type, whereas 90 (38.4 ± 3.12%) were of cystic type. The cells obtained from EBs were found to express NF‐68 and NESTIN (ectodermal lineage), BMP‐4 and α‐skeletal actin (mesodermal lineage), and α‐fetoprotein, GATA‐4 and HNF‐4 (endodermal lineage). When these EBs were cultured on gelatin‐coated dishes, they spontaneously differentiated to several cell types such as epithelial‐ and neuron‐like cells. When EBs were cultured in the presence of 1 or 2% DMSO or 10?8 m or 10?7 m retinoic acid for 25 days, ES cells could be directed to form muscle cell–like cells, the identity of which was confirmed by expression of α‐actinin by immunofluorescence and of MYF‐5, MYOD and MYOGENIN genes by RT‐PCR. MYOD was first detected on Day 10 in both treatment groups and on Day 15 in controls, whereas MYOGENIN was first detected on Day 10, Day 15 and Day 25 in the presence of retinoic acid, in the presence of DMSO and in controls, respectively. The present study demonstrates the ability of buffalo ES cell–like cells to undergo directed differentiation to cells of skeletal myogenic lineage. 相似文献
72.
73.
In this paper, the morphological transformations in Hibiscus sabdariffa stem fiber on graft copolymerization with acrylonitrile (AN) and its binary mixture with methyl acrylate (MA) and acrylamide
(Aam), using ceric ammonium nitrate — nitric acid initiator system has been reported. Different reaction parameters such as
temperature, time, initiator concentration, monomer concentration and pH were optimized to get the maximum graft yield (Pg:28.0)
and used in binary monomeric mixture to further improve the properties. The graft copolymer thus formed were characterized
by FTIR, SEM, XRD, TGA, and DTA techniques. The percentage crystallinity and crystallinity index were found to decrease with
increase in percentage grafting. The graft copolymer were found to be moisture, chemical and thermal resistant for various
advanced applications. 相似文献
74.
Sen Chauhan Indra Gupta Ashok K. Khate Keviletsu Chauhan Anuj Krishna Shankar Rao Thakur Pathak Shivendra Hazra Ritwik Singh Maneesh 《Tropical animal health and production》2010,42(8):1809-1815
The objective of the study was to evaluate the effects of genetic and non-genetic factors on production of breeding bulls
and semen quality parameters in Karan Fries crossbred male by fitting least squares analysis. Genetically, the animals were
divided into three subclasses. The non-genetic factors were season of birth, period of birth, and age group with three subclasses
each for season of birth and period of birth. Age group was classified into four subclasses. The traits generated in the study
were number of males reaching semen donation stage (AFSC) and first freezing (AFSF), age at last semen collection (ALSC) and
last freezing (ALSF), age at disposal (AD), and lifetime semen production traits (up to 1 year after first freezing). The
effect of period of birth was significant for AFSC, AFSF, ALSC, and AD. It was also significant for total ejaculates produced
in a year. The age group had significant effect on AFSF. Effect of genetic group was significant for freezable ejaculates
produced in a year, for frozen semen doses produced in a year, and for number of ejaculates cryoprocessed in a year. Season
had no statistically significant effect on any of the traits studied. The influence of period revealed that the most of the
traits of breeding bulls improved after intermediate period, which could be due to better care, training, feeding, and other
management practices in the latter years. However, no consistent trend could be established for the effects of genetic groups
and other non-genetic causes on the traits considered. 相似文献
75.
Effects of a short‐term supranutritional selenium supplementation on redox balance,physiology and insulin‐related metabolism in heat‐stressed pigs 下载免费PDF全文
F. Liu P. Celi J. J. Cottrell S. S. Chauhan B. J. Leury F. R. Dunshea 《Journal of animal physiology and animal nutrition》2018,102(1):276-285
Heat stress (HS) disrupts redox balance and insulin‐related metabolism. Supplementation with supranutritional amounts of selenium (Se) may enhance glutathione peroxidase (GPX) activity and reduce oxidative stress, but may trigger insulin resistance. Therefore, the aim of this experiment was to investigate the effects of a short‐term high Se supplementation on physiology, oxidative stress and insulin‐related metabolism in heat‐stressed pigs. Twenty‐four gilts were fed either a control (0.20 ppm Se) or a high Se (1.0 ppm Se yeast, HiSe) diet for 2 weeks. Pigs were then housed in thermoneutral (20°C) or HS (35°C) conditions for 8 days. Blood samples were collected to study blood Se and oxidative stress markers. An oral glucose tolerance test (OGTT) was conducted on day 8 of thermal exposure. The HS conditions increased rectal temperature and respiration rate (both p < .001). The HiSe diet increased blood Se by 12% (p < .05) and ameliorated the increase in rectal temperature (p < .05). Heat stress increased oxidative stress as evidenced by a 48% increase in plasma advanced oxidized protein products (AOPPs; p < .05), which may be associated with the reductions in plasma biological antioxidant potential (BAP) and erythrocyte GPX activity (both p < .05). The HiSe diet did not alleviate the reduction in plasma BAP or increase in AOPPs observed during HS, although it tended to increase erythrocyte GPX activity by 13% (p = .068). Without affecting insulin, HS attenuated lipid mobilization, as evidenced by a lower fasting NEFA concentration (p < .05), which was not mitigated by the HiSe diet. The HiSe diet increased insulin AUC, suggesting it potentiated insulin resistance, although this only occurred under TN conditions (p = .066). In summary, HS induced oxidative stress and attenuated lipid mobilization in pigs. The short‐term supranutritional Se supplementation alleviated hyperthermia, but did not protect against oxidative stress in heat‐stressed pigs. 相似文献
76.
Pyometra was recorded in five camels and Actinomyces pyogenes (Corynebacterium pyogenes) was isolated from pus of the affected camels. 相似文献
77.
R K Tamang G J Jha M K Gupta H V Chauhan B K Tiwary 《Veterinary immunology and immunopathology》1988,19(3-4):299-305
Cypermethrin toxicity was produced in mice by intra-peritoneal injection of the pesticide at 50 mg/kg body weight per day for 26 days, and in goats by drenching with cypermethrin at 41.6 mg/kg body weight per day for 30 days. The status of cell-mediated immunity (CMI) was assessed by the 2,4-dinitrofluorobenzene (DNFB) skin sensitivity test. The results indicated significant depression of CMI in the cypermethrin-treated mice and goats. In addition, the humoral immune reaction of the goats intoxicated with cypermethrin was estimated by enumeration of the plaque-forming B-lymphocytes. The rate of plaque formation in the lymphocyte suspension of cypermethrin-treated goats was significantly reduced and the diameter of the plaques was also significantly lower than in that of control animals. The results indicated that cypermethrin suppressed both CMI and the antibody-forming ability of lymphocytes. This immunosuppressive action of cypermethrin is being reported for the first time. 相似文献
78.
Five short-duration pigeonpea (Cajanus cajan (L.) Millsp.) genotypes were grown at three plant populations in three locations during the 1986 and 1988 rainy seasons, to determine the physiological basis of observed variations in yield. Significant differences were found in seed yield (Y), crop growth rate (C), and the durations of vegetative (Dv) and reproductive (Dr) growth, and partitioning (P). These were attributable to genotypes and their interactions with environments (except for C). Variation in C, Dr, and P together explained 78 % of the observed variation in Y due to different genotypes and environments. Crop growth rate alone contributed about 71 % of the variation in Y, and reached an optimum value of around 6.5 kg ha?1°Cd?1. Crop growth rates increased with the duration of the vegetative period and with plant population. However, a negative relationship between C and P resulted in plant population having little effect on seed yield. The maximum-yielding genotype, ICPH 8 had the highest C and an intermediate P. 相似文献
79.
Subsurface drain spacing is underestimated by the equations that do not account for evaporation-evapotranspiration (ET) lowering the water table in drained lands. An analytical solution is proposed to evaluate water table behaviour in subsurface drained lands in the presence of ET. A piecewise linear model is proposed and used to describe any realistic functional relation between ET and depth to water table. Characteristics of the solution have been highlighted with the help of numerical examples for which drainage parameters have been chosen from two actually operating drainage systems installed in semi-arid regions. The accuracy of the proposed solution has been verified with the existing numerical scheme as well as by comparing the water table behaviour with the observed field data. Application of the solution in subsurface drainage design has been illustrated which suggests that drain spacing at this particular site could be increased by 9 to 18% if the contribution of ET in lowering the water table is taken into account. 相似文献
80.