全文获取类型
收费全文 | 175篇 |
免费 | 4篇 |
专业分类
林业 | 13篇 |
农学 | 13篇 |
基础科学 | 5篇 |
43篇 | |
综合类 | 17篇 |
农作物 | 15篇 |
水产渔业 | 9篇 |
畜牧兽医 | 46篇 |
园艺 | 4篇 |
植物保护 | 14篇 |
出版年
2023年 | 1篇 |
2022年 | 10篇 |
2021年 | 2篇 |
2020年 | 2篇 |
2019年 | 1篇 |
2018年 | 3篇 |
2017年 | 9篇 |
2016年 | 5篇 |
2015年 | 2篇 |
2014年 | 8篇 |
2013年 | 13篇 |
2012年 | 10篇 |
2011年 | 9篇 |
2010年 | 5篇 |
2009年 | 11篇 |
2008年 | 7篇 |
2007年 | 11篇 |
2006年 | 3篇 |
2005年 | 2篇 |
2004年 | 4篇 |
2003年 | 6篇 |
2002年 | 3篇 |
2001年 | 4篇 |
2000年 | 3篇 |
1999年 | 3篇 |
1998年 | 2篇 |
1997年 | 1篇 |
1996年 | 1篇 |
1995年 | 3篇 |
1992年 | 1篇 |
1991年 | 3篇 |
1989年 | 1篇 |
1988年 | 1篇 |
1986年 | 4篇 |
1985年 | 1篇 |
1984年 | 1篇 |
1983年 | 2篇 |
1982年 | 1篇 |
1981年 | 2篇 |
1980年 | 4篇 |
1979年 | 3篇 |
1978年 | 3篇 |
1977年 | 1篇 |
1975年 | 1篇 |
1974年 | 1篇 |
1973年 | 1篇 |
1971年 | 1篇 |
1969年 | 1篇 |
1967年 | 2篇 |
排序方式: 共有179条查询结果,搜索用时 15 毫秒
91.
92.
Shashi Kala Yadav Salil Sehgal 《Plant foods for human nutrition (Dordrecht, Netherlands)》1997,50(3):239-247
The present investigation was conducted to study the effect of selected processing and storage methods on the concentration
of ascorbic acid and β-carotene in Bathua and fenugreek, leaves. Methods included storage of leaves with or without polythene
bags for 24 and 48 h in a refrigerator at 5°C; at 30°C in polythene bags; drying (sun and oven); blanching (5, 10, 15 min);
open pan and pressure cooking. Ascorbic acid content of fresh leaves was 220.97 to 377.65 mg and β-carotene content was 19.00
to 24.64 mg/100 g, DW. The percent loss of ascorbic acid ranged from 2.03 to 8.77 and 45.15 to 66.9 while lower losses (0.0
to 1.75 and 1.63 to 2.84) of β-carotene were observed in leaves, stored in, the refrigerator and at 30°C, respectively. A
markedly greater reduction in ascorbic acid and β-carotene was observed in dried, blanched and cooked leaves. The study data
suggest that storage of leaves in refrigeration, drying in oven, blanching for a short time and cooking in a pressure cooker
results in better retention of these two vitamins. 相似文献
93.
This paper examines various factors which contribute to performance of water user associations. The capability of collective organizations such as WUAs to develop appropriate rules and to enforce them while keeping the level of conflict low is considered to be the core of organizational performance. We focus on the processes in collective organizations with greater attention to costs of working together. Four factors representing benefits and costs, the rights held by the WUAs, magnitude of expected benefits, external assistance received and leadership explain most of the differences in performance. The prospect of benefits is a necessary condition for individuals to act collectively. But it is not sufficient. Expected organizational costs need to be low. The prospect of costs being low or being absorbed by one or more individuals – either external agents or internal leaders – provides an encouraging environment. Effective internal leadership appears to be essential as it can lead to greater congruence in interests and greater possibility of mutual assurances which are critical for collective action. 相似文献
94.
G. R. Mahajan R. N. Sahoo R. N. Pandey V. K. Gupta Dinesh Kumar 《Precision Agriculture》2014,15(5):499-522
In situ, non-destructive and real time mineral nutrient stress monitoring is an important aspect of precision farming for rational use of fertilizers. Studies have demonstrated the ability of remote sensing to monitor nitrogen (N) in many crops, phosphorus (P) and potassium (K) in very few crops and none so far to monitor sulphur (S). Specially designed (1) fertility gradient experiment and (2) test crop experiments were used to check the possibility of mineral N–P–S–K stress detection using airborne hyperspectral remote sensing. Leaf and canopy hyperspectral reflectance data and nutrient status at booting stage of the wheat crop were recorded. N–P–S–K sensitive wavelengths were identified using linear correlation analysis. Eight traditional vegetation indices (VIs) and three proposed (one for P and two for S) were evaluated for plant N–P–S–K predictability. A proposed VI (P_1080_1460) predicted P content with high and significant accuracy (correlation coefficient (r) 0.42 and root means square error (RMSE) 0.180 g m?2). Performance of the proposed S VI (S_660_1080) for S concentration and content retrieval was similar whereas prediction accuracies were higher than traditional VIs. Prediction accuracy of linear regressive models improved when biomass-based nutrient contents were considered rather than concentrations. Reflectance in the SWIR region was found to monitor N–P–S–K status in plants in combination with reflectance at either visible (VIS) or near infrared (NIR) region. Newly developed and validated spectral algorithms specific to N, P, S and K can further be used for monitoring in a wheat crop in order to undertake site-specific management. 相似文献
95.
The decrease in stratospheric ozone has heightened concern over the consequences of increasing solar UV-B radiation on plants. The present study was conducted to evaluate the interactive effects of supplemental UV-B (sUV-B: 280–320 nm) and mineral nutrients on a leafy vegetable amaranthus (Amaranthus tricolor L. var Pusa badi) under natural field conditions in a dry tropical environment. The nutrient treatments were recommended dose of NPK, 1.5 times recommended dose of NPK, 1.5 times recommended dose of N and 1.5 times recommended dose of K sUV-B radiation inhibited growth and biomass accumulation and altered the patterns of biomass partitioning. In K amended plants larger proportion of biomass has been translocated to roots which further increased under sUV-B treatment. The application of 1.5 times recommended dose of NPK reduced the magnitude of yield loss. The study shows that amaranthus is a potentially UV-B sensitive species and a higher NPK dose above the recommended is required to minimize the adverse impact of sUV-B. 相似文献
96.
Varun PrabhakarMulinti Raghunath PhD Tarunbir SinghNarinder Singh Saini DVM PhD Jitender MohindrooShashi Kant Mahajan PhD 《Journal of Equine Veterinary Science》2013
A 7-month-old, 180-kg, female foal was presented with open diaphyseal fracture of the left third metacarpal bone. The fractured limb was stabilized preoperatively with external coaptation. Open reduction and internal fixation were done using 4.5-mm broad dynamic compression plate, which was applied in a neutralization manner. Postoperatively, external support with padded bandage reinforced with gutter splint made of fiber glass was provided. The incisional infection and the contaminated wound on medial aspect of the metacarpal were managed with regular dressing. Complete radiographic union and functional recovery were noticed by 4 months postoperatively. Open diaphyseal fractures can be managed by proper preoperative fracture stabilization, wound management, and fixation methods using bone plate and external coaptation. 相似文献
97.
Jamuna Valsalan Atish Kumar Chakravarty Chandrashekhar Santosh Patil Shakti Kant Dash Atul Chandrashekhar Mahajan Vijay Kumar Vikas Vohra 《Tropical animal health and production》2014,46(6):967-974
Selection for genetically superior Murrah buffaloes under Network Project on Buffalo Improvement, India, is presently based on milk yield, and it was observed that even in the absence of any direct selection pressure applied on fertility, there has been a downward trend in fertility associated with the selection for milk yield. The aim of the study was to develop selection indices which include fertility besides milk yield in Murrah buffaloes. Data pertaining to 1,224 lactation records spread over a period of 19 years were recorded and analyzed in the study. The negative association of pregnancy rate (fertility) with a 305-day milk yield (?0.08?±?0.04) and wet average (?0.12?±?0.02) indicated the importance of incorporating fertility trait in the construction of selection index. Four types of selection indices were constructed and evaluated. Two indices were developed using expected producing ability 305-days milk yield (EPAMY) with 6.5 and 4 % fat in milk along with expected fertilizing ability (EFA). The other two indices developed consist of expected producing ability wet average (EPA WA) and EFA. The index involving (EPA WA and EFA) was found to be a more effective selection criterion in our herd, as the accuracy of index was more (0.61), in comparison to the index involving EPA MY and EFA. The robustness of selection index was assessed by increasing the relative economic values of included traits by 25 and 50 %, and accuracy of the index remains almost stable without much change. The developed selection strategy involving EPA WA and EFA should be considered for the genetic evaluation of Murrah buffaloes, as it has a potential for maximizing the lifetime reproduction and production performances of the breed. 相似文献
98.
P. N. Dhingra L. P. Agarwal V. M. Mahajan S. C. Adlakha K. K. Baxi 《Zoonoses and public health》1981,28(4):336-340
Chlamydien Gruppentantigen: Seine Herstellung und Anwendung in der Komplementbindungsreaktion zur Messung des Antikörpergehalts in Tieren gegen die Chlamydiengruppe Ein hochwirksames, ätherextrahiertes Gruppenantigen (Titer 1:256) wurde hergestellt. Benutzt wurde Stamm Bour von Chlamydia Trachomatis. Bei dieser Technik werden nur solche Einrichtungen benötigt, wie sie in jedem Routinelabor zu finden sind. Insgesamt wurden 886 Seren von gesund erscheinenden Rindern, Büffeln, Schafen und Ziegen (etwa 200 Stück pro Tierart) mit Hilfe der KBR gegen das Chlamydien-Gruppenantigen getestet. Serologisch positiv reagierten 53% der Rinder, 44% der Büffel, 52,9% der Ziegen und 38% der Schafe. Es wurden Titer zwischen 1:4 und 1:64 beobachtet. Die Verbreitung der Gruppen-Antikörper bei diesen Tieren, die keine offensichtliche Erkrankung zeigen, wird diskutiert. 相似文献
99.
100.
Microwave-assisted extraction (MAE) was carried out for the simultaneous determination of the insecticides thiamethoxam [(EZ)-3-(2-chloro-1,3-thiazol-5-ylmethyl)-5-methyl-1,3,5-oxadiazinan-4-ylidene(nitro)amine], imidacloprid [1-(6-chloro-3-pyridylmethyl)-N-nitroimidazolidin-2-ylideneamine], and the fungicide carbendazim (methyl benzimidazol-2-ylcarbamate) in vegetable samples. Five crop samples consisting of cabbage, tomatoes, chilies, potatoes, and peppers were fortified with the three pesticides and subjected to MAE followed by cleanup to remove coextractives prior to analysis by high-performance liquid chromatography. Using the selected microwave exposure time and power setting, the recoveries of the three pesticides from the fortified vegetable samples ranged from 68.1 to 106%. The corresponding recoveries for samples processed simultaneously but without microwave exposure ranged from 37.2 to 61.4%. The recoveries by MAE were comparable to those obtained by the conventional blender extraction technique. The precision of the MAE method was demonstrated by relative standard deviations of <7% for the three pesticides. The cooked cabbage and tomato samples showed no breakdown of the parent compounds, and the recoveries of three pesticides were comparable to those obtained with the uncooked samples. 相似文献