全文获取类型
收费全文 | 411篇 |
免费 | 13篇 |
国内免费 | 1篇 |
专业分类
林业 | 26篇 |
农学 | 9篇 |
70篇 | |
综合类 | 18篇 |
农作物 | 11篇 |
水产渔业 | 83篇 |
畜牧兽医 | 186篇 |
植物保护 | 22篇 |
出版年
2023年 | 3篇 |
2022年 | 2篇 |
2021年 | 15篇 |
2020年 | 6篇 |
2019年 | 3篇 |
2018年 | 11篇 |
2017年 | 6篇 |
2016年 | 9篇 |
2015年 | 15篇 |
2014年 | 22篇 |
2013年 | 46篇 |
2012年 | 28篇 |
2011年 | 27篇 |
2010年 | 20篇 |
2009年 | 9篇 |
2008年 | 23篇 |
2007年 | 31篇 |
2006年 | 28篇 |
2005年 | 29篇 |
2004年 | 23篇 |
2003年 | 20篇 |
2002年 | 15篇 |
2001年 | 14篇 |
2000年 | 7篇 |
1999年 | 4篇 |
1998年 | 2篇 |
1997年 | 1篇 |
1996年 | 3篇 |
1993年 | 1篇 |
1988年 | 1篇 |
1980年 | 1篇 |
排序方式: 共有425条查询结果,搜索用时 140 毫秒
351.
Mari Inohana Takeshi Komine Yoshiaki Tanaka Osamu Kurata Shinpei Wada 《Journal of fish diseases》2023,46(1):47-59
Mycobacterium marinum is a prevalent nontuberculous mycobacterium (NTM)-infecting teleosts. Conversely, little is known about mycobacteriosis in elasmobranchs, and M. marinum infection has never been reported from the subclass. This study investigated the histopathological characteristics and localization of this mycobacterium through molecular analysis of two captive sharks, a scalloped hammerhead Sphyrna lewini and a Japanese bullhead shark Heterodontus japonicus, exhibited in the same aquarium tank. We detected genital mycobacteriosis caused by M. marinum infection using molecular analyses, including polymerase chain reaction (PCR) and DNA sequencing targeting the 60 kDa heat-shock protein gene (hsp65), and peptide nucleic acid–fluorescence in situ hybridization (PNA-FISH) targeting the 16S rRNA gene. Both sharks showed granulomas in connective tissues of the gonads without central necrosis or surrounding fibrous capsules, which is unlike the typical mycobacterial granulomas seen in teleosts. This study reveals that elasmobranchs can be aquatic hosts of M. marinum. Because M. marinum is a representative waterborne NTM and a potential zoonotic agent, cautious and intensive research is needed to overcome a lack of data on the relationship between NTM and the aquatic environment in association with this subclass of Chondrichthyes. 相似文献
352.
以数字地图为基础,以日本早池峰山地域为研究对象,研究不同地表拟合方法及DEM精度对坡度计算的影响:1)最小曲面法、逆距离法和剖面法3种不同的地表拟合方法对基于DEM计算的坡度影响很小。2)DEM精度对基于其计算的坡度有相当大的影响,随着DEM精度的降低,计算出的平均坡度变小。3)DEM精度对不同坡度级别有着不同的影响。这种影响按坡度大致可以分为3种类型:当坡度为0°~10°时,采用低精度的DEM将低估测面坡度,使这一坡度级面积增加;当坡度为10°~35°时,采用低精度的DEM将过高地估侧地面坡度,使这一坡度级面积减少;当坡度大于35°时,DEM精度对坡度的影响很小,坡度的频率分布随着DEM精度变化基本维持不变。 相似文献
353.
Yuchengmin Zhang Hideto Tsutsui Nobuhiro Yamawaki Yasuhiro Morii Gregory N. Nishihara Shiro Itoi Osamu Arakawa Tomohiro Takatani 《Marine drugs》2021,19(12)
Toxic crabs of the family Xanthidae contain saxitoxins (STXs) and/or tetrodotoxin (TTX), but the toxin ratio differs depending on their habitat. In the present study, to clarify within reef variations in the toxin profile of xanthid crabs, we collected specimens of the toxic xanthid crab Zosimus aeneus and their sampling location within a single reef (Yoshihara reef) on Ishigaki Island, Okinawa Prefecture, Japan, in 2018 and 2019. The STXs/TTX content within the appendages and viscera or stomach contents of each specimen was determined by instrumental analyses. Our findings revealed the existence of three zones in Yoshihara reef; one in which many individuals accumulate extremely high concentrations of STXs (northwestern part of the reef; NW zone), another in which individuals generally have small amounts of TTX but little STXs (central part of the reef; CTR zone), and a third in which individuals generally exhibit intermediate characteristics (southeastern part of the reef; SE zone). Furthermore, light microscopic observations of the stomach contents of crab specimens collected from the NW and CTR zones revealed that ascidian spicules of the genus Lissoclinum were dominant in the NW zone, whereas those of the genus Trididemnum were dominant in the CTR zone. Although the toxicity of these ascidians is unknown, Lissoclinum ascidians are considered good candidate source organisms of STXs harbored by toxic xanthid crabs. 相似文献
354.
Yuki Okashita Heng Wang Shiori Tsue Osamu Nishimiya Kazuhiro Ura Yasuaki Takagi 《Fisheries Science》2017,83(5):803-810
In the present study, we examined the localization of the major yolk protein (MYP) in the intestine of the sea urchin Strongylocentrotus intermedius. First, partial MYP complementary DNA was isolated from the sea urchin intestine. The expression level of MYP messenger RNA (mRNA) along the sea urchin digestive tract is highest in the intestine, so we performed in situ hybridization and immunohistochemical analysis using this tissue. No MYP mRNA was detected in the luminal epithelium, connective tissue, muscle tissue, or coelomic epithelium by in situ hybridization analysis. Positive immunohistochemical staining was observed in the luminal epithelium, inner epithelium and connective tissue, the signal being strongest in the latter. We conclude that MYP synthesized in the inner epithelial cells is moved to and stored in connective tissue and the luminal epithelium, before being secreted into the body cavity and the inner digestive cavity of the sea urchin. 相似文献
355.
本文是通过在城市不同环境、不同季节少年儿童学习、生活娱乐的初步调查后,得出的结论.必须在城市改建规划中,挖掘城市用地的潜力,为少年儿童提供足够数量的游戏场.我们对四个街区儿童游戏空间进行分析得出的一些有趣的资料,应引起专家们的关注 相似文献
356.
Osamu Hashiguchi Yuko Yamaguchi Shinichiro Ikezaki Tsubasa Saito Saori Igura Ryo Hirai Naomi Horiuchi Kazutoshi Tamura 《Journal of toxicologic pathology》2022,35(1):107
A female TOYO beagle dog showed porencephaly and visual organ abnormalities. At necropsy, there was a cavity filled with cerebrospinal fluid in the right cerebral hemisphere and an adhesion area between the cerebral cortex and the skull, which was partially thickened. Additionally, the right optic nerve showed a slight decrease in diameter. Histopathological examination revealed increased glial fibers and collagen fibers, hemosiderin deposition, and an increased number of microglia in the adhesion area, along with a marked reduction of the cerebral parenchyma. In the right eyeball, the retina and optic nerve showed focal atrophy in the nerve fiber layer and inner granular layer to full retinal atrophy and hypoplasia of the myelinated nerve fibers, respectively. Electron microscopic examination revealed hypoplasia of the myelin sheath of nerve fibers in the right optic nerve. This is an extremely rare case of porencephaly and congenital optic nerve hypoplasia, along with independent retinal thinning. 相似文献
357.
Yui KOBATAKE Nao NISHIMURA Hiroki SAKAI Syunsuke IWANA Osamu YAMATO Naohito NISHII Hiroaki KAMISHINA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2020,82(11):1704
A 1-year- and 11-month-old spayed female toy poodle had showed progressive ataxia and paresis in the hindlimbs since 11 months old. Magnetic resonance imaging revealed high signal intensity on T2-weighted and fluid-attenuated inversion recovery images at the thoracic and lumbar spinal cord. The dog’s neurological condition slowly deteriorated and flaccid tetraparesis was exhibited. At 4 years and 11 months old, the dog died of respiratory failure. On postmortem examination, eosinophilic corkscrew bundles (Rosenthal fibers) were observed mainly in the thoracic and lumbar spinal cord. Histological features were comparable to previously reported cases with Alexander disease. This is a first case report to describe the clinical course and long-term prognosis of a dog with Alexander disease. 相似文献
358.
Susumu Kurinobu Daryono Prehatin Naiem Mohanmad Kenji Matsune Osamu Chigira 《Journal of Forest Research》2007,12(3):230-236
A growth model for a plantation of Paraserianthes falcataria was provisionally derived from measurements of 32 permanent plots taken over a period of 2 years in Pare, Indonesia. This
model first predicts height growth with the polymorphic site index equation. Then density-related growth and mortality, that
is, diameter and stand density, are calculated to satisfy the mathematical relationship for the reciprocal and self-thinning
equations, both of which were based on the maximum size–density line with the slope of −1.759 identified in this study. Cumulative
predictions on diameter and stand density, starting with each of three age classes, 3, 4, and 5 years after planting, and
continuing for the next 2 years, agreed well with the observations of age-class mean. An exception was for stands that were
7 years old, which were marginal, but closest to the rotation age of 8 years. Contrasting height/diameter relationships among
the three age classes were described reasonably well with this model, and the predicted basal growth area was found to agree
fairly well with observations. These results suggest that the growth model presented here has good potential for applying
size–density control for plantations of P. falcataria. However, measurements for an additional few years might be necessary to derive a model that will more accurately predict
diameter size at the rotation age. 相似文献
359.
Yuki Monden Takuya Hara Yoshihiro Okada Osamu Jahana Akira Kobayashi Hiroaki Tabuchi Shoko Onaga Makoto Tahara 《Breeding Science》2015,65(2):145-153
Sweetpotato (Ipomoea batatas L.) is an outcrossing hexaploid species with a large number of chromosomes (2n = 6x = 90). Although sweetpotato is one of the world’s most important crops, genetic analysis of the species has been hindered by its genetic complexity combined with the lack of a whole genome sequence. In the present study, we constructed a genetic linkage map based on retrotransposon insertion polymorphisms using a mapping population derived from a cross between ‘Purple Sweet Lord’ (PSL) and ‘90IDN-47’ cultivars. High-throughput sequencing and subsequent data analyses identified many Rtsp-1 retrotransposon insertion sites, and their allele dosages (simplex, duplex, triplex, or double-simplex) were determined based on segregation ratios in the mapping population. Using a pseudo-testcross strategy, 43 and 47 linkage groups were generated for PSL and 90IDN-47, respectively. Interestingly, most of these insertions (~90%) were present in a simplex manner, indicating their utility for linkage map construction in polyploid species. Additionally, our approach led to savings of time and labor for genotyping. Although the number of markers herein was insufficient for map-based cloning, our trial analysis exhibited the utility of retrotransposon-based markers for linkage map construction in sweetpotato. 相似文献
360.
Yamada O Kobayashi M Sugisaki O Ishii N Ito K Kuroki S Sasaki Y Isotani M Ono K Washizu T Bonkobara M 《Veterinary immunology and immunopathology》2011,142(1-2):101-106
Target therapy using the tyrosine kinase inhibitor imatinib is one of the new therapeutic approaches for canine mast cell tumors (MCTs). In the present report, we demonstrate a clinical response to imatinib in a dog with MCT carrying a c-kit c.1523A>T mutation. Moreover, the effect of this mutation on the phosphorylation status of KIT and the inhibitory potency of imatinib on the phosphorylation of the mutant KIT were examined in vitro. A dog with a MCT tumor mass on the right forelimb sole with lymph node metastasis and mastocytemia was treated with imatinib. The MCT mass markedly shrank and mastocytemia became undetectable with 2 weeks of treatment. The lymph node enlarged by metastasis became normal in size with 5 weeks of treatment. From the sequencing analysis of c-kit in tumor cells, a substitution mutation c.1523A>T that alters the amino acid composition (p.Asn508Ile) within the extracellular domain of KIT was identified. The mutant KIT expressed on 293 cells showed ligand-independent phosphorylation and imatinib suppressed this phosphorylation in a dose-dependent manner. From these findings, imatinib was considered to elicit a clinical response in a canine case of MCT via inhibition of the constitutively activated KIT caused by a c-kit c.1523A>T mutation. 相似文献