全文获取类型
收费全文 | 167篇 |
免费 | 5篇 |
专业分类
林业 | 10篇 |
农学 | 12篇 |
基础科学 | 2篇 |
12篇 | |
综合类 | 4篇 |
农作物 | 10篇 |
水产渔业 | 28篇 |
畜牧兽医 | 85篇 |
园艺 | 1篇 |
植物保护 | 8篇 |
出版年
2022年 | 2篇 |
2021年 | 4篇 |
2019年 | 5篇 |
2018年 | 4篇 |
2017年 | 1篇 |
2016年 | 3篇 |
2015年 | 5篇 |
2014年 | 13篇 |
2013年 | 12篇 |
2012年 | 17篇 |
2011年 | 9篇 |
2010年 | 4篇 |
2009年 | 4篇 |
2008年 | 6篇 |
2007年 | 11篇 |
2006年 | 1篇 |
2005年 | 7篇 |
2004年 | 6篇 |
2003年 | 7篇 |
2002年 | 3篇 |
2001年 | 5篇 |
2000年 | 3篇 |
1999年 | 3篇 |
1998年 | 3篇 |
1997年 | 1篇 |
1994年 | 1篇 |
1992年 | 1篇 |
1991年 | 4篇 |
1990年 | 7篇 |
1989年 | 3篇 |
1988年 | 6篇 |
1986年 | 4篇 |
1985年 | 3篇 |
1981年 | 1篇 |
1979年 | 1篇 |
1974年 | 2篇 |
排序方式: 共有172条查询结果,搜索用时 15 毫秒
71.
72.
Minami W. OKUYAMA Michito SHIMOZURU Yojiro YANAGAWA Toshio TSUBOTA 《The Journal of reproduction and development》2014,60(2):155-161
The raccoon is a seasonal breeder with a mating season in the winter. In a previous
study, adult male raccoons exhibited active spermatogenesis with high plasma testosterone
concentrations, in the winter mating season. Maintenance of spermatogenesis generally
requires high testosterone, which is produced by steroidogenic enzymes. However, even in
the summer non-mating season, some males produce spermatozoa actively despite low plasma
testosterone concentrations. To identify the factors that regulate testosterone production
and contribute to differences in spermatogenetic activity in the summer non-mating season,
morphological, histological and endocrinological changes in the testes of wild male
raccoons should be known. In this study, to assess changes in the biosynthesis, metabolism
and reactivity of testosterone, the localization and immunohistochemical staining
intensity of four steroidogenic enzymes (P450scc, P450c17, 3βHSD, P450arom) and the
androgen receptor (AR) were investigated using immunohistochemical methods. P450scc and
P450c17 were detected in testicular tissue throughout the year. Seasonal changes in
testosterone concentration were correlated with 3βHSD expression, suggesting that 3βHSD
may be important in regulating the seasonality of testosterone production in raccoon
testes. Immunostaining of P450arom and AR was detected in testicular tissues that
exhibited active spermatogenesis in the summer, while staining was scarce in
aspermatogenic testes. This suggests that spermatogenesis in the raccoon testis might be
maintained by some mechanism that regulates P450arom expression in synthesizing estradiol
and AR expression in controlling reactivity to testosterone. 相似文献
73.
Tiago W.P. Mineo Adriano O.T. CarrascoJosé A. Marciano Karin WertherAramis A. Pinto Rosangela Z. Machado 《Veterinary parasitology》2009
Neospora caninum infections in chickens have been recently described by epidemiological and experimental approaches, and these birds may be considered natural intermediate hosts of the parasite. It has been postulated that other bird species might perform this role in wildlife as well. To better understand the sylvatic life cycle of N. caninum, further studies are required. In that sense, this work aimed to observe infection kinetics in pigeons experimentally infected with N. caninum. Experimental infections were conducted in parallel with a related protozoan, Toxoplasma gondii, which has been already described as able to infect pigeons in nature. Our results demonstrated that N. caninum disseminated through various tissues of this host and induced parasite-specific IgG seroconversion. Infection parameters were similar to that observed in the T. gondii infected group, although N. caninum-infected pigeons presented lower IgG titers during acute phase. The results herein described demonstrate that pigeons are a suitable model for N. caninum infection, considering that these data are in agreement with those observed in chickens experimentally infected with this parasite. As pigeons may be revealed as important reservoirs for N. caninum infection in nature, future studies are necessary to determine the real prevalence of this parasite in this and other birds in wildlife. 相似文献
74.
Yuichi Katayose Hiroyuki Kanamori Michihiko Shimomura Hajime Ohyanagi Hiroshi Ikawa Hiroshi Minami Michie Shibata Tomoko Ito Kanako Kurita Kazue Ito Yasutaka Tsubokura Akito Kaga Jianzhong Wu Takashi Matsumoto Kyuya Harada Takuji Sasaki 《Breeding Science》2012,61(5):661-664
Soybean [Glycine max (L) Merrill] is one of the most important leguminous crops and ranks fourth after to rice, wheat and maize in terms of world crop production. Soybean contains abundant protein and oil, which makes it a major source of nutritious food, livestock feed and industrial products. In Japan, soybean is also an important source of traditional staples such as tofu, natto, miso and soy sauce. The soybean genome was determined in 2010. With its enormous size, physical mapping and genome sequencing are the most effective approaches towards understanding the structure and function of the soybean genome. We constructed bacterial artificial chromosome (BAC) libraries from the Japanese soybean cultivar, Enrei. The end-sequences of approximately 100,000 BAC clones were analyzed and used for construction of a BAC-based physical map of the genome. BLAST analysis between Enrei BAC-end sequences and the Williams82 genome was carried out to increase the saturation of the map. This physical map will be used to characterize the genome structure of Japanese soybean cultivars, to develop methods for the isolation of agronomically important genes and to facilitate comparative soybean genome research. The current status of physical mapping of the soybean genome and construction of database are presented. 相似文献
75.
76.
The morphological and genetic variations in somaclones of chili pepper (Capsicumannuum L.) derived from tissue culture were evaluated. Cotyledonary node explants of cultivars, Shishitou and Takanotsume, were
cultured on Murashige and Skoog (MS) medium supplemented with benzyladenine (BA)5 mg/l for shoots regeneration and regenerated
shoots were rooted on MS medium supplemented with naphthalene acetic acid(NAA) 0.1 mg/l and indol-3-butyric acid(IBA) 0.05
mg/l. The regenerated plants(R0) were selfed to obtain seeds for next generation (R1 lines). Qualitative characters were studied in R0generation and both qualitative and quantitative characters were studied in R1 generation. In R0 generation, variations were noticed in plant growth habit, stem color, flower color and color of unripe fruits, and expression
of anthocyanin in unripe fruits. Comparison among the R1 lines and their parents were made for morphological and agronomic characters. Significant variation among R1 lines and differences between R1 lines and their parents were observed. Genetic variations among three somaclones were revealed by random amplified polymorphic
DNA (RAPD) analysis. Variation, such as early flowering and increase of yield components, is an indication of the response
to selection for any specific character. Occurrence of productive variants among somaclones of established cultivars, like
Shishitou and Takanotsume, indicates the possibility of their improvement through somaclonal variation.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
77.
Masato Aoyama Minami Shioya Yume Tsukamoto Hitomi Hasegawa Shoei Sugita 《Animal Science Journal》2021,92(1):e13607
Ruminants are not considered to experience nausea because they do not possess the emetic reflex. This study examined the effects of administration of cisplatin (cis-diamminedichloro platinum (II): CDDP), a common emetic agent, on the behavior of goats. In Experiment 1, adult Shiba goats received intravenous (IV) administration of CDDP. CDDP-administered goats spent a shorter time feeding (P < 0.01), lied down earlier (P < 0.01), and spent a longer period lying down (P < 0.01) than the saline-administered control goats, and sometimes, they directed their face downward and close their eyes. These behavioral responses were followed by a significant (P < 0.01) increase in plasma cortisol (Cor) levels, which indicated that goats experienced stress. The dose dependency was found in the extent of the CDDP effects. In Experiment 2, the effects of pretreatment of ondansetron (Ond), an antiemetic agent, were examined. Pretreatment of Ond extended the latency of lying (P < 0.01), shortened the time spent lying (P < 0.05), and reduced the extent of the increase in plasma Cor levels (P < 0.01). These results suggested that CDDP administration generated some state of stress in goats via the similar physiological mechanisms as emesis-caused stress in emetic species. 相似文献
78.
T Kamio Y Ito K Fujisaki T Minami 《Nippon juigaku zasshi. The Japanese journal of veterinary science》1990,52(1):43-48
For a period of one year Haemaphysalis longicornis ticks were collected in a pasture from vegetation by dragging flannel cloth and from soil samples at monthly intervals. Nymphal ticks were assessed for Theileria infection. Salivary glands were stained with methylgreen-pyronin and examined for parasite masses. Nymphal H. longicornis infected with Theileria sergenti were found in all samples during 12 months including the winter. After shortening the prefed period on rabbits to 24 hours, the parasite masses could be detected in the salivary glands of nymphs collected in the grazing season, from May to October, while no parasite masses were detected in other season. It was suggested that the environmental factors in the grazing season might influence on the maturation of parasites in the salivary glands of ticks. 相似文献
79.
Enucleation was performed in 10-year-old sexually intact female mixed-breed German Shepherd Dog. Histologic examination revealed that the dog had an uveal amelanotic melanoma of the eye. The tumor consisted of anaplastic cells with a high mitotic index, indicating malignancy. On examination 3 months after enucleation, the dog had difficulty breathing and nasal discharge. Radiography revealed pulmonary metastasis. The dog was euthanatized. Necropsy revealed diffuse metastasis involving various organs. 相似文献
80.
Detection of IgG antibodies to Neospora caninum and Toxoplasma gondii in dogs examined in a veterinary hospital from Brazil. 总被引:1,自引:0,他引:1
T W Mineo D A Silva G H Costa A C von Ancken L H Kasper M A Souza D D Cabral A J Costa J R Mineo 《Veterinary parasitology》2001,98(4):239-245
A total of 163 dogs with neuromuscular, respiratory and/or gastrointestinal disorders, was admitted at the Veterinary Hospital, Federal University of Uberlandia, Brazil, and submitted to serology for Toxoplasma gondii and Neospora caninum. Assays for T. gondii included indirect haemagglutination (IHA), indirect fluorescent antibody (IFAT-Tg), immunoenzymatic (ELISA), and immunoblotting (IB-Tg). Assays for N. caninum included IFAT-Nc and immunoprecipitation (IP-Nc). Based on concordant results by three serological tests (IHA, IFAT-Tg and ELISA) for T. gondii, and divergent results further confirmed by IB-Tg for reactivity to TgSAG1, the 163 sera were divided into two groups: 59 (36%) Tg-seropositive samples and 104 (64%) Tg-seronegative samples. Antibodies to Neospora were detected in 11 (6.7%) out of 163 analyzed dog sera, with 5 (3.1%) samples reactive to both parasites (Tg+/Nc+), and 6 (3.7%) reactive only to Neospora (Tg-/Nc+). Antibodies only to T. gondii were found in 54 (33%) samples. Among the 11 Neospora-positive sera analyzed by IB-Tg, the five sera Tg+/Nc+ showed strong reactivity to Toxoplasma antigens, especially to TgSAG1 (p30). No reactivity was observed to TgSAG1 in the six samples Tg-/Nc+. By IP-Nc, two highly immunodominant antigens (29 and 35kDa proteins) were recognized by all 11 IFAT-Nc positive sera. Our results suggest that the infection by N. caninum can be concomitantly present in dogs from this area, although less common, and therefore should be considered in the differential clinical diagnosis with T. gondii in dogs presenting neuromuscular, respiratory and/or gastrointestinal disorders. 相似文献