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121.
M I Walash A Abou Ouf F B Salem 《Journal of the Association of Official Analytical Chemists》1982,65(6):1445-1451
New oxidimetric titrants, bromamine T, dibromohydantoin, N-bromophthalimide, and N-bromosuccinimide, were applied to the determination of ephedrine.HCl, norephedrine.HCl, and methyldopa. Direct potentiometric and visual indicator titration methods as well as back-titration procedures have been developed for their determination. Oxidation of ephedrine and norephedrine produces benzaldehyde, which is extracted from pH 11.0 phosphate buffer with ether or hexane and determined spectrophotometrically at 242 nm. Beer's law is obeyed in the concentration range from 0.2 to 2 mg ephedrine.HCl and from 0.15 to 1.9 mg norephedrine.HCl. Methyldopa is determined titrimetrically and spectrophotometrically. In addition, this drug acts as a self-indicator: Solutions change from colorless to red, which gradually disappears with continuous addition of brominating agent and shaking. Phosphate buffer is used to produce adrenochrome, characterized by its pink color which can be measured at 485 nm in a working range from 40 to 650 micrograms. 相似文献
122.
M. E. Abdel Hamid H. H. Ramadan Dr. F. M. Salem G. Y. Osman 《Journal of pest science》1981,54(6):81-82
Zusammenfassung Baumwolle, Weizen, Mais, Sojabohne, Zwiebel, Kichererbse und Sesam wurden hinsichtlich ihrer Anfälligkeit gegen die WurzelnematodenMeloidogyne javanica undM. incognita incrita untersucht. Sesam und Mais waren gegen beide Nematodenarten resistent. Baumwolle wurde vonM. javanica nicht befallen. Dagegen wurden Zwiebel und Sojabohne von diesem Nematoden stark geschädigt. Die statistische Analyse zeigte signifikante Befallsunterschiede zwischen den Wirtspflanzen undMeloidogyne-Arten.
Mit 2 Tabellen 相似文献
Susceptibility of certain field crops to some Nematoda infection, Meloidogyne javanica (Treub) and M. incognita acrita (Kofoid & White) chitwood
Varietal susceptibility of certain field crops were tested. Sesame and maize were resistant toM. javanica andM. incognita acrita infection. Cotton was resistant toM. javanica only. Onion and soybean were highly infected withM. javanica in comparison with the other tested hosts. Soybean also was highly infected withM. incognita acrita. Wheat showed the presence of the lowest of nematode population of the two species on its roots. Severity of galls was paralleled to the mentioned nematode populations.Statistical analysis of the data indicates that there were significant differences between the tested hosts. Also, the interaction between nematode species and hosts was significant.
Mit 2 Tabellen 相似文献
123.
An area of 50 feddans cultivated with soybeans was treated withBacillus thuringiensis (B.t.) baits againstAgrotis ypsilon and 60 feddans were sprayed withB.t. spray againstSpodoptera littoralis. WhenB.t. baits were used, the percentage of kill ofA. ypsilon reached 96.1–96.4% compared to 97.4–98% kill on using hostathion baits. WhenB.t. was sprayed againstS. littoralis, a percentage of larval kill 88.3% was obtained. This increased to 97.3% after the second application. On the other hand, the precentage of kill reached 96.8% when lannate was sprayed once. The average yield was 1.54 tons/fed. whenB.t. was sprayed twice againstS. littoralis and 1.42 tons/fed. when sprayed once. Areas, treated with lannate gave 1.44 tons/fed., while in the untreated area the yield was comparatively low being 0.83 tons/fed.Mith 4 tables 相似文献
124.
M. H. Khalil E. A. Afifi M. A. Salem S. M. Zahed 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2000,117(2):129-142
Lactation traits and reproductive performance of three trials of crossing Holstein cattle (H) and German Friesians (F) raised in a hot climatic were evaluated. The first 90-day (M90), 305-day (M305) and total milk yield (TMY), 305-day milk yield per day of calving interval (MCI1), total milk yield per day of calving interval (MCI2) along with length of lactation period (LP), age at first calving (AC1) and calving interval (CI) were used. For these traits, a genetic model was applied for each trial separately to obtain estimates of individual (GI ) and maternal (GM ) additive effects, individual (HI ) and maternal (HM ) heterosis and individual recombination effect (RI ). Data of 8045 normal lactations from the three trials were analysed. Among the crossbreds obtained in the three trials, cows of ¾H¼F ranked first in their lactational performance. Estimates of GI and GM were generally large and in favour of H cows (daughters) and dams for most milk-yield traits, CI and AC1 in the three trials. Estimates of HI in crossbred cows for milk traits, CI and AC1 were mostly negative and reveal that crossing F with H was associated with a reduction in milk-yield traits, shorter CI and earlier AC1 along with longer LP in the three trials. Estimates of HM for milk yields, LP, AC1 and CI in daughters of crossbred dams were mostly negative. Recombination losses in crossbred cows were negative for milk-yield traits, AC1 and CI in most cases. 相似文献
125.
Sulphadiazine, sulphatiazole and sulphamerazine were shown to be excreted through the ruminal wall and salivary glands of cows. These sulphonamides had a slight inhibitory effect on cellulose digestion and on the activity of rumen infusoria. Acetylation of the sulphonamides occurred to a slight extent. Sulphatiazole was more acetylated (16.2 per cent) than sulphadiazine (7.0 per cent) or sulphamerazine (8.4 per cent). The rate of elimination of the three compounds, as indicated by their half lives, showed that sulphathiazole was the most rapidly excreted (2 h), whereas sulphadiazine and sulphamerazine were more slowly excreted, 5.4 and 7.1 h respectively. 相似文献
126.
R. Rojo-Rubio J. F. Vázquez-Armijo P. Pérez-Hernández G. D. Mendoza-Martínez A. Z. M. Salem B. Albarrán-Portillo A. González-Reyna J. Hernández-Martínez S. Rebollar-Rebollar D. Cardoso-Jiménez E. J. Dorantes-Coronado J. G. Gutierrez-Cedillo 《Tropical animal health and production》2009,41(5):715-721
Cattle production is one of the most important livestock activities in the rural areas of Mexico, with most of the national
territory dedicated to it, in addition to the use of the most agricultural supplies and forages resources, as well as agricultural
and agro-industrial by-products. Mexico is placed among the ten first meat and milk producer countries worldwide, being the
Mexican tropical zone one of the main suppliers of such products. One of the main milk sources is the dual purpose cattle,
such systems can be described as those that produce milk (daily milking) and meat (calf after weaning), on every productive
cycle. They are mainly located in developing regions and characterized by using low-technology and in poor environments, consequently
productive levels are considered low. Milk is destined for self-consumption or for sale at local markets and calf after weaning
is sold at local feedlots or for export. Regarding to the little information available about the dual purpose systems, the
present work is intended to discuss the main characteristics of cattle production in dual purpose systems in Mexico. 相似文献
127.
Salma H. AbuHafsa Ayman A. Hassan Luis M. Camacho Abdelfattah Z. M. Salem 《Tropical animal health and production》2014,46(7):1119-1125
Forty-eight growing New Zealand White male rabbits aged 6 weeks (874?±?1.3 g initial body weight (BW)) were used to study effects of partial replacement of berseem hay (BH) with Salix tetrasperma hay (ST) on growth and physiological responses. Rabbits were allotted to one of four diets of 12 rabbits each for 75 days in a completely randomized design. The treatments were as follows: control (30 % BH), ST25 (7.5 % ST?+?22.5 % BH), ST50 (15 % ST?+?15 % BH), ST75 (22.5 % ST?+?7.5 % BH). Nutrient digestibility coefficients, nutritive value and N utilization of rabbits fed with the ST50 rations were higher (P?0.05) than the other groups. Final live BW, average daily gain, feed intake and feed efficiency of rabbits fed ST25 and ST50 were higher (P?0.05) than those fed ST75 and the control. Serum biochemical metabolites of urea, creatinine, aspartate amino transferase and alanine amino transferase concentrations varied among diets, with the rank order (P?0.05) ST75?>?ST25 and ST50?>?control. Glucose level was higher (P?0.05) for the control than the other diets. Rabbits fed with the mixed diets of ST had lower (P?0.05) total lipids, cholesterol and triglycerides levels than those fed with control. Haematological indices of packed cell volume, haemoglobin, red blood cells, white blood cells and lymphocyte counts were lower (P?0.05), but monocyte was higher, in rabbits fed with the ST75 than the other groups. However, other haematological parameters were similar among diets. Since all the performance and blood parameters were within normal ranges for healthy rabbits, and there were no signs of toxicity, we conclude that partial replacement of BH by ST improves rabbit growth performance, and did not impact rabbit health. 相似文献
128.
Calpains are calcium-dependent neutral proteases responsible for many cellular functions. The two forms of calpain ubiquitously
expressed in mammalian tissues are known as μ-calpain and m-calpain. We report here the identification of a novel calpain
that is similar to but distinct from the μ- and m-calpains in rainbow trout. The cDNA of the novel gene is 2623 bp in length
with a single open reading frame. The predicted protein (676 amino acids) contains the conserved calpain characteristic domains
that include: domain I (pro peptide), II (cysteine catalytic site), III (electrostatic switch), and IV (calmodulin-like) with
five Ca2+-binding EF hands. Northern blot and RT-PCR analyses demonstrated that the novel calpain gene is predominantly expressed in
rainbow trout gills. Comparison of the novel protein with the ubiquitously expressed calpains and several mammalian tissue-specific
calpains revealed that the novel calpain is an orthologue of the mammalian digestive tract specific calpain (calpain 9). 相似文献
129.
Hany S. Abdo Khalil Abdelrazek Khalil Salem S. Al-Deyab Hamoud Altaleb El-Sayed M. Sherif 《Fibers and Polymers》2013,14(12):1985-1992
Silver nanoparticles imbedded in polyacrylonitrile (PAN) nanofibers and converted into carbon nanofibers by calcination was obtained in a simple three-step process. The first step involves conversion of silver ions to metallic silver nanoparticles, through reduction of silver nitrate with dilute solution of PAN. The second step involves electrospinning of viscous PAN solution containing silver nanoparticles, thus obtaining PAN nanofibers containing silver nanoparticles. The third step was converting PAN/Ag composites into carbon nanofibers containing silver nanoparticles. Scanning electron microscopy (SEM) revealed that the diameter of the nanofibers ranged between 200 and 800 nm. Transmission electron microscopy (TEM) and energy dispersive spectroscopy (EDS) showed silver nanoparticles dispersed on the surface of the carbon nanofibers. The obtained fiber was fully characterized by measuring and comparing the FTIR spectra and thermogravimetric analysis (TGA) diagrams of PAN nanofiber with and without imbedded silver nanoparticles, in order to show the effect of silver nanoparticles on the electrospun fiber properties. The obtained carbon/Ag composites were tested as gram-class-independent antibacterial agent. The electrosorption of different salt solutions with the fabricated carbon/Ag composite film electrodes was studied. 相似文献
130.
Abstract In field-scale trials at Hamoul in the north of the Nile delta in 1967 and 1968, certain herbicides applied to a soil heavily infested with barnyardgrass (Echinochloa crus-galli) gave very satisfactory results. Taking into account both grass control and increase in rice stand, molinate and propanil at 3-4 Ib/feddan* were shown to be most effective. Molinate used either as a liquid or granular formulation gave excellent results when applied pre-flood (liquid) or post-emergence (liquid and granules). Propanil used post-emergence gave good results provided that the field was drained 24 hours before treatment and flooded again 24 hours after. 相似文献