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21.
Successful fruit set depends on several reproductive processes including pollen germination and tube growth processes. An experiment was conducted to determine the effects of temperature on pollen germination characteristics and to identify species/genotypic differences in Capsicum using the cumulative temperature response index (CTRI) concept. Pollen was collected from plants of seven genotypes from five Capsicum species, adapted to various parts of the world and grown outdoors in large pots. The pollen was subjected to in vitro temperatures ranging from 15 to 50 °C at 5 °C intervals. Pollen germination and tube lengths were recorded for all species after 24 h of incubation at the respective treatments. Species/genotypes differed significantly for in vitro pollen germination percentage and pollen tube length with mean values of 78% and 734 μm, respectively. The mean cardinal temperatures (Tmin, Topt, and Tmax) averaged over genotypes, were 15.2, 30.7, and 41.8 °C for pollen germination and 12.2, 31.2, and 40.4 °C for pollen tube growth. The CTRI of each species/genotype calculated as the sum of eight relative individual stress response values, such as maximum pollen germination, maximum pollen tube length; Tmin, Topt, and Tmax temperatures of pollen germination, and pollen tube lengths, identified species tolerance to high temperatures. Capsicum annum cv. Mex Serrano from Mexico was identified as tolerant, C. chacoense cv. 1312 and C. spp. cv. Cobanero from Argentina and Guatemala, respectively as intermediate and C. frutescens cv. Early Spring Giant from China, C. annum cv. Long Green from South Korea, C. spp. cv. NM89C130 and C. pubescens cv. 90002 from Guatemala as sensitive to high temperatures. The tolerant species/genotypes can be used in breeding programs to develop new genotypes that can withstand high temperature conditions both in the present climate and particularly in a future warmer climate. 相似文献
22.
23.
Development of Core Subset of Finger Millet Germplasm Using Geographical Origin and Data on 14 Quantitative Traits 总被引:6,自引:0,他引:6
Hari D. Upadhyaya C. L. L. Gowda R. P. S. Pundir V. Gopal Reddy Sube Singh 《Genetic Resources and Crop Evolution》2006,53(4):679-685
Finger millet [Eleusine coracana (L.) Gaertn.] is an important cereal food crop in Africa and South Asia. It is a hardy crop that can be grown in very diverse
environments from almost at sea level to about 2400 m.a.s.l. Finger millet has an excellent food value as its seeds contain
protein ranging from 7 to 14% and are particularly rich in methionine amino acid, iron, and calcium. Despite all these merits,
this crop has been neglected from the main stream of crop improvement research. One of the means to boost its production and
productivity is to enhance utilization of finger millet germplasm to breed superior varieties. Keeping this objective in view,
a core subset of finger millet germplasm (622 accessions) based on origin and data on 14 quantitative traits was developed
from the entire global collection of 5940 accessions held in the genebank at ICRISAT, Patancheru, India. The comparison of
means, variances, frequency distribution, Shannon-Weaver diversity index (H′) and phenotypic correlations indicated that the
core subset represents the entire collection. These tests indicated that sampling was optimal and the diversity has been captured
very well in the core subset. The correlation analysis indicated that panicle exsertion and longest finger length could be
given lower priority in the future germplasm evaluation work of finger millet. 相似文献
24.
Namratha Reddy David M. Crohn Frederick F. Ernst Vijayasatya N. Chaganti 《Compost science & utilization》2013,21(3-4):164-176
ABSTRACT Most composters in the United States use open-windrows. During high intensity precipitation events, uncontained water running off of the surface of the compost piles can potentially contaminate surface waters with nutrients and metals. Water that is absorbed poses no runoff concern but may threaten groundwater quality. To gain insight into these processes, stormwater runoff fractions and water holding capacity of compost piles have been characterized for greenwaste (GW) and biosolids (BS) materials. Laboratory scale experiments were conducted using days 1, 7, and 14 materials representing three different stages of composting. This study also evaluated sloped and flat-top as different pile geometries and surfactant use for promoting infiltration. Results indicate that fresh materials were most hydrophobic and the infiltration rates increased with increased composting times. The water storage capacity of the compost pile increased with the age of the compost pile. Compost water storage capacities could not be reliably estimated as the difference between field capacity and as-received water contents. 相似文献
25.
K. Ramesh K. Sammi Reddy I. Rashmi A.K. Biswas 《Communications in Soil Science and Plant Analysis》2016,47(3):369-374
Analysis of differential pore-volume distribution (DPVD) patterns of a commercial Clinoptilolite has been conducted experimentally using an analyzer by measuring the N2 adsorption isotherm. The commercial material was fractionated by sieving through sequential sieves: <125 µ (Z8; fine), 125–250 µ (Z9; medium), and >250 µ (Z10; coarse). The DPVD of the fractions were calculated from the hysteresis loop according to the adsorption and desorption curves of Dollimore-Heal (DH) model. The adsorption cycle had produced dissimilar differential pore volume distribution patterns. For the 10-nm pore width, fine and medium fractions had a maximum pore volume up to 0.0016 cm3/g nm, while the coarse fraction had a little greater value up to 0.002 cm3/g nm. Moreover, the medium fraction had too many hills and valleys in the DPVD. However, the desorption cycle–based DH analysis did not show any marked variation in the DPVD pattern. 相似文献
26.
1. Wheat, triticale 131 or triticale 72‐S could replace up to half the maize in broiler diets without affecting performance. Replacing more of the maize on either an equal nitrogen basis or a weight basis adversely affected performance.
2. Triticale 72‐S appeared to be superior to triticale 131 as a direct replacement for maize, but both grains were inferior to maize as energy sources. 相似文献
27.
R A Kramer M D Schaber A M Skalka K Ganguly F Wong-Staal E P Reddy 《Science (New York, N.Y.)》1986,231(4745):1580-1584
The gag-pol gene of HTLV-III (human T-lymphotropic virus), the virus linked to AIDS (acquired immune deficiency syndrome), was expressed in yeast, and processing of the gag precursor into proteins of the same size as those in the virion was observed. Processing of the gag gene in yeast cells mimics the process that naturally occurs in mammalian cells during maturation of virions. Therefore it was possible to perform mutational analysis of the virus genome to localize the gene that codes for the protease function to the amino terminal coding region of the pol gene. Since this region overlaps the gag gene, it is likely that ribosomal frameshifting occurs from gag to pol. Antibodies in all of the AIDS patients' sera tested recognized the yeast synthesized gag proteins, although the sera showed differences in relative reactivity to the individual gag proteins and the precursor. This yeast system should be valuable not only for production of viral proteins for diagnostic or vaccine purposes but also for analysis of the genetics and biochemistry of viral gene functions--parameters that are difficult to study otherwise with this virus. 相似文献
28.
Inhibitory activity of homoisoflavonoids from Caesalpinia sappan against Beauveria bassiana 总被引:2,自引:0,他引:2
Niranjan Reddy VL Ravikanth V Jansi Lakshmi VV Suryanarayan Murty U Venkateswarlu Y 《Fitoterapia》2003,74(6):600-602
Four homoisoflavonoids, 4-O-methylsappanol (1), protosappanin A (2), brazilin (3) and caeasalpin J (4), isolated from Caesalpinia sappan, were tested for inhibitory activity against Beauveria bassiana. Compound 1 showed activity against this fungus. 相似文献
29.
30.
The essential oil of Aristolochia indica, containing beta-caryophyllene and alpha-humulene as major constituents, was found to show a moderate antibacterial activity. 相似文献