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111.
M. E. E. Mahmoud S. A. Mohamed F. M. Khamis M. A. I. Basher S. Ekesi 《EPPO Bulletin》2019,49(2):359-363
Bactrocera zonata is an alien fruit fly which was introduced into Sudan in 2012 and spread throughout the country, severely hampering the production and export of fruit and vegetable crops. Cataloguing indigenous natural enemies of pests, especially parasitoids, is key to successful biological control programmes, to mitigate damage and decrease reliance on insecticides. This study was conducted to determine the parasitoids of B. zonata in two orchards in Gezira State, Sudan from November 2015 to May 2016 and from February to December, 2016 and to determine their role in natural control of the pest. Three parasitoids emerged from puparia of B. zonata, these were: Tetrastichus giffardianus Silvestri (Eulophidae), an Aganaspis sp. (Figitidae: Eucoilinae) and a Psyttalia sp. (Braconidae Opiinae). Tetrastichus giffardianus was the most numerous parasitoid throughout the study period. The mean percentages of B. zonata from guava fruits that were parasitized by T. giffardianus for the whole study period were 13.7% and 13.2% with 3.1 ± 0.3 and 2.8 ± 2.4 parasitoids per puparium at Fadasi and Gazirat Elfil sites respectively. Data on the temporal abundance of T. giffardianus is presented. Strenuous efforts should be considered to involve the reported natural enemies of B. zonata in integrated management programmes for fruit flies in Sudan. 相似文献
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Zusammenfassung Die Virulenz von 13 Bacilluspr?paraten (2 Handelspr?parate vonBacillus thuringiensis var,thuringiensis Berliner und 11 Laboratoriums-Pr?parate von verschiedenen Arten und Variet?ten) gegen 3 ?gyptische Noctuiden (Agrotis ypsilon Rott.,Laphygma exigua Hbn. undProdenia litura Fab.) wurden untersucht. 50 Raupen von jeder Art (6–7 Tage alt) wurden für jede Behandlung und die Kontrolle verwendet (einen
Tag auf behandeltes Laub vonTrifolium alexandrinum gesetzt). Die Resultate ergaben, da?Laphygma in 9 F?llen sehr empfindlich ist, wobei sich ein deutlicher Unterschied zu den beiden anderen Arten ergab.
In 7 dieser F?lle folgte aufLaphygma Prodenia und in 2 F?lleAgrotis. Besonders wirksame Pr?parate waren: Biospor 2802 gegenLaphygma, Bacillus thuringiensis var.thuringiensis 2172 gegenProdenia undB. entomocidus var.subtoxicus 1179 gegenAgiotis. In den meisten F?llen wurde kein direkter Zusammenhang zwischen Virulenz und Zahl der lebenden Sporen gefunden.
Die Autoren sind zu Dank verpflichtet Herrn Dr. A. Burgerjon, Station des Recherches de Lutte Biologique (La Miniere), Herrn Dr. G. Benz ETH-Entomological Institute (Zürich), Herrn J. Wolf, Department of Agriculture (Leeds) und der N. R. R. L. (Illinois) für die Beschaffung der Bakterien-Pr?parate, die in vorliegender Arbeit verwendet wurden. 相似文献
Summary The virulence of 13 Bacillus preparations (2 commercial formulations ofBacillus thuringiensis var.thuringiensis Berliner and 11 laboratory preparations of different varieties and species) on 3 Egyptian noctuids (Agrotis ypsilon Rott.,Laphygma exigua Hbn. andProdenia litura Fab.) was tested. Fifty larvae of each species (6–7 days-old) were used for each treatment and for the control (one day voluntary ingestion on foliage ofTrifolium alexandrinum). Results revealed thatLaphygma is most susceptible in 9 cases with marked difference between it and both other species. In 7 of these casesLaphygma was followed byProdenia and in 2 cases byAgrotis. Most virulent preparations were: Biospore 2802 againstLaphygma, Bacillus thuringiensis var.thuringiensis 2172 againstProdenia andB. entomocidus var.subtoxicus 1179 againstAgrotis. In most cases no direct relationship was observed between virulence and number of viable spores in dose.
Die Autoren sind zu Dank verpflichtet Herrn Dr. A. Burgerjon, Station des Recherches de Lutte Biologique (La Miniere), Herrn Dr. G. Benz ETH-Entomological Institute (Zürich), Herrn J. Wolf, Department of Agriculture (Leeds) und der N. R. R. L. (Illinois) für die Beschaffung der Bakterien-Pr?parate, die in vorliegender Arbeit verwendet wurden. 相似文献
115.
An outbreak of cerebrospinal microfilariosis in 23 kids, representing a whole kid crop, occurred on a farm in Qassim, Central Saudi Arabia. The morbidity and mortality rates were 100%. Clinical signs, in kids from the fourth to sixth week of age, manifested as weakness in the hind legs followed by incoordination of movement and feet dragging. Seven to ten days later, the hind legs were completely paralyzed, and within a week the front legs were also paralyzed. The animals continued to feed, drink and suckle normally, and were in good health. Paralyzed kids were helped to suckle by the farm attendants. With time, loss of control of motor functions occurred and the ability to hold the head in upright position was lost, ability to eat or drink was lost. The infected kids health deteriorated and they eventually died. Two dead kids were postmortemed. With the exception of a meningeal haemorrhage seen in one kid, no obvious macroscopic lesions were seen in any of the autopsied animals. Histopathological examination of the spinal cord and brain showed different microfilaria of different sizes between the meninges and the nervous tissue. This indicated that development of the parasite occurred in the nervous tissue. The larger microfilaria contained black deposits, most likely to be digested blood, in their guts. It is likely that the parasites are haematophagus. The main lesions caused by the microfilaria were migratory traumatic haemorrhagic tracts in the spinal cord and the brain. These sometimes contained parts of the microfilariae. In the brain malacic lesions and sporadic aggregates of lymphocytes were also noted. 相似文献
116.
J.L. Christiansen S. Raza B. Jørnsgård S.A. Mahmoud R. Ortiz 《Genetic Resources and Crop Evolution》2000,47(4):425-430
Landraces of white lupin (Lupinus albus L.) collected in Egypt were evaluated along with locally developed cultivars and selected foreign germplasm for yield and major morphological characteristics in five different locations. These locations represent different soil types and climatic conditions in Egypt. The results showed an outstanding performance of the local cultivar checks across traditional locations for lupin cultivation, which supports the utilization of local germplasm for further improvement of locally adapted lupins in Egypt. The results further suggest that local landrace germplasm may be an important source of alleles for shortening the vegetative period, reducing plant height and stem length, as well as for improving some yield components as number of pods and seeds per plant. The genotype-by-location interaction was significant for all characteristics. Mass selection in the Egyptian germplasm collection of white lupin has the potential for enhancing yield, especially in germplasm adapted to newly reclaimed desert locations. 相似文献
117.
The effect of in planta TIBA and L-proline onin vitro seedlings and cell culture of sugar beet was investigated. Sterilized seeds were grownin vitro on 1/2 MS medium supplemented with 0 or3 mg/l TIBA. Calli obtained on young leaves cultured on MS medium containing 1 mg/l
BAP, were used for the initiation of cell suspension cultures using MS basal composition supplemented with 0 or 50 mM proline.
Aliquots of 1 ml from cell suspension culture were inoculated onto the first somatic embryo induction MS medium containing
TIBA 0.5 mg/l, BAP 1.0 mg/l, and proline at 0 or 50 mM. After three weeks of culture, embryogenic calli were transferred to
the second embryo induction medium supplemented with NAA and BAP at 0.2 and 0.5 mg/l, respectively. The frequency of somatic
embryos of calli obtained from in plantaTIBA together with proline treatments on average was20 which was higher than that of the other treatments.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
118.
Samy M ELEAWA Mahmoud A ALKHATEEB Fahaid H ALHASHEM Ismaeel BIN-JALIAH Hussein F SAKR Hesham M ELREFAEY Abbas O ELKARIB Riyad M ALESSA Mohammad A HAIDARA Abdullah S. SHATOOR Mohammad A KHALIL 《The Journal of reproduction and development》2014,60(2):115-127
This study was performed to investigate the protective and therapeutic effects of
resveratrol (RES) against CdCl2-induced toxicity in rat testes. Seven
experimental groups of adult male rats were formulated as follows: A) controls+NS, B)
control+vehicle (saline solution of hydroxypropyl cyclodextrin), C) RES treated, D)
CdCl2+NS, E) CdCl2+vehicle, F) RES followed by CdCl2
and M) CdCl2 followed by RES. At the end of the protocol, serum levels of FSH,
LH and testosterone were measured in all groups, and testicular levels of TBARS and
superoxide dismutase (SOD) activity were measured. Epididymal semen analysis was
performed, and testicular expression of Bcl-2, p53 and Bax was assessed by RT-PCR. Also,
histopathological changes of the testes were examined microscopically. Administration of
RES before or after cadmium chloride in rats improved semen parameters including count,
motility, daily sperm production and morphology, increased serum concentrations of
gonadotropins and testosterone, decreased testicular lipid peroxidation and increased SOD
activity. RES not only attenuated cadmium chloride-induced testicular histopathology but
was also able to protect against the onset of cadmium chloride testicular toxicity.
Cadmium chloride downregulated the anti-apoptotic gene Bcl2 and upregulated the expression
of pro-apoptotic genes p53 and Bax. Resveratrol protected against and partially reversed
cadmium chloride testicular toxicity via upregulation of Bcl2 and downregulation of p53
and Bax gene expression. The antioxidant activity of RES protects against cadmium chloride
testicular toxicity and partially reverses its effect via upregulation of BCl2 and
downregulation of p53 and Bax expression. 相似文献
119.
Fauci AS Johnston MI Dieffenbach CW Burton DR Hammer SM Hoxie JA Martin M Overbaugh J Watkins DI Mahmoud A Greene WC 《Science (New York, N.Y.)》2008,321(5888):530-532
The need to broaden research directed at answering fundamental questions in HIV vaccine discovery through laboratory, nonhuman primate (NHP), and clinical research has recently been emphasized. In addition, the importance of attracting and retaining young researchers, developing better NHP models, and more closely linking NHP and clinical research is being stressed. In an era of a level budget for biomedical research at the U.S. National Institutes of Health (NIH), HIV/AIDS vaccine research efforts will need to be carefully prioritized such that resources to energize HIV vaccine discovery can be identified. This article summarizes progress and challenges in HIV vaccine research, the priorities arising from a recent summit at NIAID, and the actions needed, some already under way, to address those priorities. 相似文献
120.
Mahmoud G. El Sebaei Nagah Arafat Reham A. El-Shafei Mohamed A. El-Adl Amany Farag Abeer E. Aziza Abdelfattah H. Eladl 《Journal of animal physiology and animal nutrition》2021,105(1):129-139
This study was carried out to evaluate the effects of induced urolithiasis by high dietary calcium (Ca) or protein levels on biochemical analyte levels, redox status, selected inflammatory cytokines and histopathology in chickens. A total of 90 one-day-old white Hy-Line chicks were fed basal control diets containing 20% crude protein (CP) and 1% Ca until they reached 44 days of age. After that, the birds were divided into three groups (30 birds per group). All management factors (light, temperature, ventilation, stock density and diet) were identical among the three groups throughout the study except for the dietary Ca and protein percentages. Group I was fed a control diet containing 20% CP and 1% Ca, group II was fed a high-Ca diet containing 5% Ca, and group III was fed a high-protein diet containing 25% CP. Our findings clearly demonstrated that dietary imbalance (caused by high-Ca or high-CP levels) per se in chickens was physiologically harmful, as it was accompanied by post-mortem lesions; biochemical, redox status and histopathological alterations; and upregulation of inflammatory cytokines (interleukin (IL)-1β and IL-6). In particular, the birds fed the high-Ca diet clearly exhibited the most obvious alterations in most of the endpoints. In conclusion, this study constitutes the first extensive investigation of the effects of high-Ca or high-protein diets induced urolithiasis on growth performance, redox status, inflammatory cytokine levels and pathological characterization in chickens. 相似文献