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191.
Neonatal diarrhea occurred at two swine breeding farms in Hokkaido. Ten piglets aged 2 to 4 days were examined. Grossly, significant changes were confined to the small intestine. The mucous membrane was muddy and thickened. The intraluminal contents from the jejunum to the colon were liquid and yellow. In the small intestine, numerous Gram-negative bacilli preferentially adhered to the apex of villi. The mucosa was erosive with villous atrophy. There were bacilli also in the lamina propria and in the cytoplasm of degenerated enterocytes. Nonhemolytic Escherichia coli strains, belonging to serogroup E. coli O18 and possessing K88 fimbriae, were isolated from the small intestine. They could not be classified into any of the diarrheagenic E. coli groups because of the absence of genes of LT, STh, STp, VT1, VT2, eae, invE, and ipaH. After inoculation of the isolates on HEp-2 cells, some bacilli were engulfed by cytoplasmic projections resembling membrane ruffles and subsequently were localized in cytoplasmic vacuoles or free in the cytoplasm. These findings support the view that the present E. coli O18 is a new invasive strain enteropathogenic to piglets. 相似文献
192.
Yamato O Matsunaga S Takata K Uetsuka K Satoh H Shoda T Baba Y Yasoshima A Kato K Takahashi K Yamasaki M Nakayama H Doi K Maede Y Ogawa H 《The Veterinary record》2004,155(23):739-744
A five-month-old, female Japanese domestic shorthair cat with proportionate dwarfism developed neurological disorders, including ataxia, decreased postural responses and generalised body and head tremors, at between two and five months of age. Leucocytosis due to lymphocytosis with abnormal cytoplasmic vacuolations was observed. The concentration of G(M2)-ganglioside in its cerebrospinal fluid was markedly higher than in normal cats, and the activities of beta-hexosaminidases A and B in its leucocytes were markedly reduced. On the basis of these biochemical data, the cat was diagnosed antemortem with G(M2)-gangliosidosis variant 0 (Sandhoff-like disease). The neurological signs became more severe and the cat died at 10 months of age. Histopathologically, neurons throughout the central nervous system were distended, and an ultrastructural study revealed membranous cytoplasmic bodies in these distended neurons. The compound which accumulated in the brain was identified as G(M2)-ganglioside, confirming G(M2)-gangliosidosis. A family study revealed that there were probable heterozygous carriers in which the activities of leucocyte beta-hexosaminidases A and B were less than half the normal value. The Sandhoff-like disease observed in this family of Japanese domestic cats is the first occurrence reported in Japan. 相似文献
193.
Fujinami N Hosoi Y Kato H Matsumoto K Saeki K Iritani A 《The Journal of reproduction and development》2004,50(2):171-178
Developmental potential of bovine embryos that are not artificially activated after intracytoplasmic sperm injection (ICSI) is generally very low. In this study, we investigated effects of artificial activation with ethanol on kinetics of maturation promoting factor (MPF) activity (p34(cdc2) kinase activity) and development of bovine oocytes following ICSI. Treatment of oocytes with ethanol at 4 h after ICSI improved their first cleavage and further preimplantation development (51% vs. 13%, 14% vs. 4%: treatment with vs. without ethanol, respectively). MPF activity of oocytes was lowered until at least 2 h after ICSI. In oocytes without activation after ICSI, MPF activity temporarily elevated at 6 h after ICSI, whereas this phenomena was not observed in the oocytes treated with ethanol. Furthermore, MPF activity was elevated 20 h after ICSI in oocytes activated with ethanol, whereas this elevation of MPF activity was not shown in oocytes without activation. These results indicate that the stimulus of sperm was sufficient to lower MPF activity of oocytes following ICSI, and moreover the activation treatment of bovine oocytes with ethanol after ICSI served to maintain the low levels of MPF activity until the next cell cycle started. 相似文献
194.
Melon yellow spot virus: A Distinct Species of the Genus Tospovirus Isolated from Melon 总被引:1,自引:0,他引:1
ABSTRACT A tospovirus-like virus recovered from netted melon was transmitted by Thrips palmi in a persistent manner but had different cytopathological features from tospoviruses previously reported. Viral nucleocapsid (N) was purified with two protective reagents, 2-mercaptoethanol and L-ascorbic acid, and RNA extracted from the viral nucleocapsid was used for genomic analysis. The virus had a genome consisting of three single-stranded RNA molecules. The open reading frame on the viral complementary strand, located at the 3' end of the viral S RNA, encoded the N protein. The 3' terminus of this RNA also contained an eight-nucleotide sequence similar to the conserved sequence at the 3' end of genomic RNA molecules of tospoviruses. These features of the viral genome are identical to those of tospoviruses; therefore, this virus is considered to belong to the genus Tospovirus. Its N protein comprised 279 amino acids and had a molecular mass of 31.0 kDa. Comparisons of its amino acid sequence with those of known tospoviruses revealed less than 60% identity. This melon virus is concluded to be a distinct species in the genus Tospovirus, and the name Melon yellow spot virus is proposed. 相似文献
195.
Kato Sumie Koike Takayoshi Lei Thomas T. Hsieh Chang-Fu Ueda Kunihiko Mikami Tetsuo 《New Forests》2000,19(1):109-114
Mitochondrial DNA restriction fragment length polymorphisms were used to examine cytoplasmic diversity within a relic-like population of Fagus hayatae, located in northern Taiwan. Fifteen trees were surveyed for three restriction endonucleases (BamHI, EcoRI and HindIII) and five mitochondrial gene probes (atpA, atp6, atp9, coxI and coxII). The analysis failed to reveal any polymorphisms, an observation that suggests cytoplasmic uniformity in the F. hayatae population examined. It is also interesting to note that the chondriome type of our F. hayatae samples is very close to that characteristic of F. crenata populations in the southernmost area of Japan. 相似文献
196.
海北高寒草甸辐射能量的收支及植物生物量季节变化 总被引:10,自引:5,他引:5
高寒草甸植物生长,可用Logistic方程描述。生物量的瞬时增长率过程是一个先缓慢增大,后快速增大,逐渐达到最大值,然后快速降低,最后缓慢下降,逐渐逼近零;生物量达到最大时需累积78d左右;根据生物量的变化,将生长过程划分为返青期、茂盛期和枯黄期。枯黄期的反射率明显高于返青期和茂盛期,而返青期与茂盛期的反射率之间没有差异;返青期与茂盛期的日均辐射能量差异不显著(日均总辐射:Z=0.64,P=0.81=0.05;日均辐射净:Z=0.87,P=0.44=0.05;日均有效辐射:Z=0.92,P=0.37=0.05);返青期和茂盛期的日均辐射能量均显著地高于枯黄期(日均总辐射:H=45.36,df=2,P<0.01;日均辐射净:H=32.41,df=2,P<0.01;日均有效辐射:H=12.69,df=2,P<0.01)。有效辐射和反射辐射是影响地上生物量最重要的两个变量,但两个变量对地上生物量的作用效应各异,有效辐射是正效应,而反射辐射则是负效应。 相似文献
197.
Imazaki I Homma Y Kato M Vallone S Yorinori JT Henning AA Iizumi H Koizumi S 《Phytopathology》2006,96(9):1000-1008
ABSTRACT A collection 160 isolates of Cercospora kikuchii was made from South America and 245 from Japan. DNA fingerprint patterns were analyzed based on amplified fragment length polymorphism among the sample isolates, dividing the isolates into seven lineages (I to VII). Partial nucleotide sequence analyses of the beta-tubulin gene supported this division into seven lineages. Lineages I and III commonly existed in South America and Japan. In all, 136 of the 160 isolates from South America and 223 of the 245 isolates from Japan belonged to lineage I, indicating that lineage I was the major lineage in each area; 5 isolates from South America and 8 isolates from Japan belonged to lineage III. Lineages II (12 isolates) and IV (2 isolates) were specific to Japan and lineages V (3 isolates), VI (1 isolate), and VII (15 isolates) specifically existed in South America. These results suggest that the population genetic structure of C. kikuchii was different between South America and Japan, but the dominance of lineage I was common between the two areas. 相似文献
198.
199.
So Hanaoka Ching-Te Chien Shun-Ying Chen Atsushi Watanabe Suzuki Setsuko Kazutaka Kato 《Annals of Forest Science》2014,71(5):575-584
? Context
Little is known about the potential of gene flow and resulting genetic structures of trees employing sea-drifting seed dispersal in island populations.? Aims
Current genetic structure and the magnitude of historical gene flow were estimated in island populations of Calophyllum inophyllum L., a typical plant employing sea-drifting seed dispersal.? Methods
Samples were collected from the northern extreme of the species’ distribution (Taiwan and the Sakishima, Daito, and Ogasawara Islands, Japan) and genotyped using 15 EST-SSR markers. Genetic differentiation (F ST and AMOVA), genetic structure (STRUCTRE analysis), and historical gene flow (assignment testing) were determined.? Results
Frequent gene flow within and rare gene flow among island groups was determined using assignment testing. Clear genetic structures were also detected using the STRUCTURE analysis, which demonstrated differentiation between dominant clusters among geographically constructed island groups.? Conclusions
The potential for gene flow via sea-drifting seed dispersal was high, and this was possible even among small islands. However, the extent and frequency of gene flow were not great enough to prevent genetic differentiation in a range of over a few hundred kilometers. 相似文献200.
Incident rainfall partitioning and canopy interception modeling for an abandoned Japanese cypress stand 总被引:1,自引:0,他引:1
Interception loss (E i) in forests has been studied widely. However, E i parameters and modeling as well as spatial patterns of throughfall (TF) in abandoned Japanese cypress (Chamaecyparis obtusa) plantations remain poorly documented. In this study, gross precipitation (P G), stemflow (SF), and TF were monitored in an unmanaged 32-year-old Japanese cypress stand throughout the 2011 rainy season. Results indicate that P G partitioning into TF, SF, and E i were, respectively, 64.2 ± 3.6, 10.6 ± 0.6, and 25.2 ± 1.1 % of the 880.8 mm cumulative P G from 29 rainfall events. Direct throughfall proportion (p) and drainage from the canopy contributed about 14 ± 7 and 50 ± 21 % of the total TF for the events, respectively. The mean canopy storage capacity (S) was 2.4 ± 0.7 mm. The coefficient of variability (CV) of TF rate decreased asymptotically with increasing P G amount, ranging from 16 to 56 % with median 26 %. The CV of TF rate was not significantly correlated with canopy cover (r = 0.152, P = 0.521, n = 20) and distance from the nearest trunk (r = 0.196, P = 0.408, n = 20). Based on the revised Gash analytical model, the total simulated E i was close to the observed, with a general underestimation magnitude of 5.7 %. The E i components were quantified, and most of the interception loss (62.9 %) evaporated during rainfall, while 26.8 % evaporated after rainfall ceased. Climatic and forest structural parameters required by the model were identified and analyzed by sensitivity analysis, implying that the revised Gash analytical model is robust and reliable enough for abandoned Japanese cypress plantations in a maritime climate. 相似文献