全文获取类型
收费全文 | 328篇 |
免费 | 14篇 |
国内免费 | 1篇 |
专业分类
林业 | 18篇 |
农学 | 7篇 |
基础科学 | 1篇 |
47篇 | |
综合类 | 19篇 |
农作物 | 10篇 |
水产渔业 | 48篇 |
畜牧兽医 | 181篇 |
园艺 | 4篇 |
植物保护 | 8篇 |
出版年
2023年 | 1篇 |
2022年 | 3篇 |
2021年 | 8篇 |
2020年 | 9篇 |
2019年 | 7篇 |
2018年 | 5篇 |
2017年 | 5篇 |
2016年 | 13篇 |
2015年 | 7篇 |
2014年 | 5篇 |
2013年 | 34篇 |
2012年 | 19篇 |
2011年 | 19篇 |
2010年 | 9篇 |
2009年 | 12篇 |
2008年 | 23篇 |
2007年 | 29篇 |
2006年 | 12篇 |
2005年 | 17篇 |
2004年 | 17篇 |
2003年 | 13篇 |
2002年 | 16篇 |
2001年 | 10篇 |
2000年 | 5篇 |
1999年 | 5篇 |
1998年 | 1篇 |
1997年 | 3篇 |
1996年 | 1篇 |
1995年 | 2篇 |
1994年 | 1篇 |
1993年 | 1篇 |
1992年 | 3篇 |
1991年 | 2篇 |
1990年 | 3篇 |
1989年 | 3篇 |
1988年 | 7篇 |
1987年 | 3篇 |
1986年 | 1篇 |
1985年 | 1篇 |
1984年 | 1篇 |
1983年 | 1篇 |
1981年 | 1篇 |
1980年 | 1篇 |
1978年 | 1篇 |
1974年 | 1篇 |
1973年 | 1篇 |
1971年 | 1篇 |
排序方式: 共有343条查询结果,搜索用时 15 毫秒
151.
Carlos Frederico Ceccon Lanes Marcelo Hideo Okamoto Adalto Bianchini Luis Fernando Marins Luís André Sampaio 《Aquaculture Research》2010,41(9):e199-e207
The aim of this study was to evaluate the sperm quality of Brazilian flounder Paralichthys orbignyanus throughout its reproductive season. Sperm was collected at the beginning, middle and end of the breeding period. Spermatozoa density was maximum at the beginning (12.7 ± 0.92 × 109 cells mL?1) and at the end (11.8 ± 0.39 × 109 cells mL?1) of the breeding season (P<0.05). Sperm production and the percentage of spermatozoa moving fast forward increased significantly towards the end of the breeding season (P<0.05). The mean duration of progressive motility of spermatozoa was around 10 min. No difference was observed during the reproductive season in the percentage of motile cells, pH, osmolality and K+, Cl? and Mg2+ concentrations in seminal plasma. The concentration of Na+ increased throughout the breeding season, reaching 174.62 ± 12.68 mmol L?1 at the end (P<0.05). There was a decline in the concentration of Ca2+ (12.31 ± 3.08 mmol L?1) in the middle of the breeding season, which coincided with the shortest motility duration of spermatozoa. The information reported in this study should help to improve management and optimize the development of protocols for short‐term storage and cryopreservation of Brazilian flounder semen. 相似文献
152.
Mitsuo Nyuji Tetsuro Shiraishi Sethu Selvaraj Vu Van In Hajime Kitano Akihiko Yamaguchi Kumiko Okamoto Shizumasa Onoue Akio Shimizu Michiya Matsuyama 《Fisheries Science》2011,77(5):731-739
The physiological functions of pituitary gonadotropins (GtHs) are well established in higher vertebrates, whereas those in
teleosts are still poorly understood. To describe the role of GtHs during gonadal development of female chub mackerel Scomber japonicus, changes in follicle-stimulating hormone (FSH) and luteinizing hormone (LH) cells were investigated immunohistochemically
during the seasonal reproductive and spawning cycles. FSH and LH cells were identified in the different cell types of the
proximal pars distalis (PPD); FSH cells were located in the central PPD, whereas LH cells were localized along the border
of the pars intermedia. To examine changes in FSH and LH cells, the percentage of FSH or LH cell-occupying area in the PPD
was evaluated and represented as FSHβ-immunoreactive (ir) or LHβ-ir levels, respectively. FSHβ-ir levels increased significantly
from immature to the completion of vitellogenesis, whereas LHβ-ir levels were maintained at high levels from early vitellogenesis
to post-spawning. During the spawning cycle, which consisted of four stages from just after spawning to the next oocyte maturation,
both FSHβ-ir and LHβ-ir levels showed no significant changes among different stages; however, LHβ-ir levels remained relatively
high, and FSHβ-ir levels were constantly low. These results suggest that both FSH and LH may be involved in vitellogenesis
and LH may act at final oocyte maturation in female chub mackerel, although the role of FSH during the spawning cycle is still
unclear. 相似文献
153.
Tetsuro Shiraishi Kumiko Okamoto Michio Yoneda Takeshi Sakai Seiji Ohshimo Shizumasa Onoe Akihiko Yamaguchi Michiya Matsuyama 《Fisheries Science》2008,74(5):947-954
The age and growth of chub mackerel Scomber japonicus collected from the East China Sea and the northern waters off Kyushu between June 2000 and June 2001 were determined by observing
the otolith surface after dipping it in xylene. The translucent and opaque zones on the otolith surface were identified, and
the number of translucent zones was counted. Monthly changes in the frequency of fish with translucent zones on the otolith
margin, and in the marginal increments, indicated that the translucent zones were formed between April and June. The seasonal
pattern of annulus formation on the otolith became clear by observing the otoliths of fish with known ages, and the otolith
formation in wild fish was consistent with that of fish with known ages. The mean gonadosomatic index of male and female fish
was high from March to May, and spawning females were observed from mid-March to mid-May. The estimated ages were 1–5 years
for males and 1–6 years for females. The von Bertalanffy growth parameters did not significantly differ between male and female.
The model was obtained as FL
t=406×{1−exp[−0.372×(t+1.68)] 相似文献
154.
Takahiro SATO Maki SEKIGUCHI Atsuko MATSUMOTO Kaho SHIMADA Mikuya IWANAGA Mitsutaka IKEZAWA Yasuko HANAFUSA Tomoyuki SHIBAHARA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2022,84(3):342
A 31-month-old Japanese Black cow (Bos taurus) aborted at 5 months of gestation with no clinical symptoms. Histopathological examination of the placenta and fetus revealed severe necrotic placentitis associated with numerous irregular degenerative fungi and inflammatory cells. Regular filamentous fungi were also detected, without inflammatory response in the fetal digestive and respiratory organs. Both fungi had aleurioconidia and septa in the placenta and fetal organs and immunohistochemically stained with antibodies against Aspergillus spp. Aspergillus terreus was isolated from the fetal lung and abomasal contents as confirmed using mycological and molecular methods. This is the first immunohistochemical, morphological, and molecular identification of A. terreus in bovine placenta and aborted fetuses. 相似文献
155.
T. Okamoto B. Vollmerhaus H. Roos H. Waibl H. E. König 《Anatomia, histologia, embryologia》1992,21(2):127-135
A total of 83 male Japanese quails of the following age groups were used for this study: 11, 18, 25, 32, 35, 37, 39, 41, 43 days, and 7, 9, 17 weeks after hatching. Neoprene-Latex, Tensol-Cement, and the china ink were injected via the aortic arch. In most of male Japanese quails, the testes are supplied by the A. testicularis originated from the Aorta descendens through a common trunk with the A. renalis cranialis. But in only 3 quails had this artery originated directly from the Aorta descendens on either side. In 9 quails had the A. testicularis accessoria originating independently from the Aorta descendens and running cranially or caudally in short distance to the normal A. testicularis. The arteries for the Ductus deferens were divided into 3 categories. The Rami ureterodeferentiales craniales were spread out from A. testicularis or Rami epididymales. The Rami ureterodeferentiales medii came from the A. renalis media and the A. renalis caudalis. The Rami ureterodeferentiales caudales originated from the A. caudae lateralis and A. pudenda. The Receptaculum ductus deferentis, the Corpus vasculare paracloacalis and the Phallus nonprotrudens in the Cloaca were supplied from the thick Ramus cloacalis of the A. pudenda. The Ramus bursalis of this artery supplied the Glandula proctodaealis and the Bursa cloacalis, and was also thick. The arteries to the genital organs were observed in the 11 day old male quail. The A. pudenda began developing at about 30 days after hatching when the quail's body matured. While the A. testicularis began developing at about 40 days after hatching when the male Japanese quail was full of the spermatogenic activity. 相似文献
156.
157.
158.
Okamoto Y Yonemura D Miyatake K Hashimoto Y Hirano T Sakata I Minami S 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2004,66(12):1599-1601
We evaluated changes in hematology and chemical profile, and the tissue retention of hematoporphyrin derivative (HpD) following the intravenous injection in dogs. HpD at concentrations of 1, 5, 10, and 15 mg/kg was intravenously injected to 16 dogs (n=4 each) and complete blood count (CBC) and blood chemistry were performed on days 1, 3, 5, and 7 after the injection. To examine tissue retention, HpD (5 mg/kg) was administered to 15 dogs and 3 dogs were euthanized on days 1, 2, 7, 14, and 28 after the injection, respectively, to collect the skin, muscle, small intestine, spleen, kidney and liver as tissue samples. There were no significant changes in CBC and blood chemical profile except for an increase in LDH concentrations in dogs given 10 and 15 mg/kg of HpD at day 3. The levels of HpD retention in the tissues were ranked in the following order: liver > kidney > spleen > intestine > muscle > skin. 相似文献
159.
Kojima K Okamoto Y Kojima K Miyatake K Fujise H Shigemasa Y Minami S 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2004,66(12):1595-1598
Collagen synthesis was evaluated by measuring prolyl hydroxylase (PHL) activity induced within rat granulation tissue by a polyester non-woven fabric (NWF, 1 x 1 cm, 0.6 mm in thickness) impregnated with a chitin or chitosan suspension ranging in concentration from 0.1 to 10 mg/ml. In addition, PHL activity induced in rat granulation tissue by a NWF impregnated with a phosphate buffer solution was examined as a control. The PHL activity in each group remained low until 4 days post-implantation (Day 4). However, in the 10 mg chitin group, the PHL activity increased rapidly without scatter of the data at Day 7 and remained at a plateau until Day 14. In other groups, PHL activity increased linearly until Day 14. The data varied widely at Day 7. Compared to chitosan, chitin at the higher concentration was found to induce stable collagen synthesis in the early wound healing process. 相似文献
160.
To visualize water-conduction pathways in living trees, we introduced aqueous solutions of safranin and acid fuchsin into stems of Populus sieboldii Miquel. To examine the spread of each dye in the trees, we compared several techniques for preparing tissue for light microscopy. Acid fuchsin was distributed more rapidly and more widely than safranin, reflecting differences between the dye molecules in state of ionization. We prepared some sections without allowing the dye to redissolve after it had been stabilized by freeze-drying. In these sections, the dye was observed in vessels and in some of the adjacent ray parenchyma cells. Other sections were prepared without stabilizing the dye. In these sections, acid fuchsin in the sap stream left cell walls unstained, whereas safranin stained wood fibers in the vicinity of vessels, as well as the vessels themselves, provided that the sections were mounted in glycerin, which dissolves safranin. Although stained with safranin, the wood fibers contained no water. The results indicate that stabilization of the introduced dye and subsequent preparation of tissues under conditions that avoid dye resolublilization allow accurate visualization of water-conduction pathways at the cellular level. 相似文献