全文获取类型
收费全文 | 63篇 |
免费 | 6篇 |
国内免费 | 5篇 |
专业分类
1篇 | |
综合类 | 19篇 |
农作物 | 2篇 |
水产渔业 | 22篇 |
畜牧兽医 | 28篇 |
园艺 | 2篇 |
出版年
2023年 | 5篇 |
2022年 | 1篇 |
2021年 | 3篇 |
2020年 | 3篇 |
2019年 | 4篇 |
2018年 | 3篇 |
2017年 | 5篇 |
2016年 | 6篇 |
2015年 | 2篇 |
2014年 | 8篇 |
2013年 | 3篇 |
2011年 | 2篇 |
2010年 | 3篇 |
2009年 | 4篇 |
2008年 | 1篇 |
2007年 | 2篇 |
2006年 | 1篇 |
2005年 | 2篇 |
2004年 | 2篇 |
2002年 | 1篇 |
2001年 | 1篇 |
2000年 | 1篇 |
1998年 | 2篇 |
1997年 | 1篇 |
1996年 | 1篇 |
1994年 | 1篇 |
1991年 | 1篇 |
1990年 | 1篇 |
1987年 | 2篇 |
1983年 | 2篇 |
排序方式: 共有74条查询结果,搜索用时 0 毫秒
1.
2.
基于Argo数据的中西太平洋鲣渔获量与水温、表层盐度关系的初步研究 总被引:3,自引:0,他引:3
根据上海金汇远洋渔业公司2007年度在中西太平洋海域进行鲣Katsuwonus pelamis围网作业的生产数据以及Argo剖面浮标数据,利用地理信息系统软件Arcview,按1°×1°的格式绘制了各月产量、表层温度、表层盐度以及50m和200m水层温度等,并对数据进行了综合分析。结果表明:鲣的高渔获量区域主要分布于150°~153°E、160°-161°E,0°~2°S的水域;2007年最高月产量和最高单网平均日产量(CPUE)的月份分别为8月和2月;通过K—S检验,2007年最适表层温度为29.3~30.1℃,最适表层盐度为34.0~35.2;0~200m、50~200m水层的垂直温差为11℃时,渔获量达到最大。Shapiro—wilk正态性检验结果表明,渔获量与0—200m、50—200m水层的垂直温差服从正态分布关系。上述结论符合生产实践中获得的情况,表明Argo数据可以应用于渔业生产和科研中。 相似文献
3.
Five New World camelids were admitted to the Western College of Veterinary Medicine between 1996 and 2003 for evaluation of femoral fractures. There were three alpacas and two llamas. Four of the animals were female and three were less than 3 months of age. Fracture configurations consisted of distal physeal fractures (three), a comminuted diaphyseal/metaphyseal fracture, and a transverse diaphyseal fracture. Fractures were diagnosed with a combination of physical examination and radiographs in all cases. All five fractures were repaired with internal fixation and three animals were discharged from the hospital with fractures that healed. One cria underwent successful internal fixation but died from pulmonary oedema during recovery from anaesthesia. Postoperative complications were rare and limited to inadequate fracture stability in one alpaca and prolonged recovery to weight bearing in another. One llama with a comminuted metaphyseal fracture, repaired with a 4.5 mm dynamic compression plate, subsequently had catastrophic failure of the bone 17 days after surgery. Overall the clients were pleased with the outcome of discharged animals. Although femoral fractures are considered rare, they pose a unique opportunity for the large animal veterinarian to successfully achieve fracture union with the aid of internal fixation. 相似文献
4.
K. David Hyrenbach Zora McGinnis Kathleen Page Dan Rapp F. David Horgen Jennifer M. Lynch 《水产资源保护:海洋与淡水生态系统》2021,31(2):408-419
- Although the frequency of occurrence of plastic ingestion in the large-sized dolphinfish and tunas taken by the Hawai'i longline fishery is very low (frequency of occurrence < 5% of sampled individuals), the ingestion of plastic in smaller-sized specimens caught with pole-and-line gear by commercial and recreational fishers has not been investigated.
- This study examined ingestion of >0.25 mm marine plastic debris (MPD) by four predatory fish species caught by commercial fishers around the Main Hawaiian Islands, and documented ingestion in three species: 85.7% of albacore tuna (n = 7), 40.0% of skipjack tuna (n = 10) and 12.5% of dolphinfish (n = 8).
- Yellowfin tuna (n = 10) did not contain any MPD, probably owing to the high proportion of empty stomachs (60%).
- For skipjack tuna, the frequency of occurrence of MPD ingestion was significantly higher for the smaller-sized specimens caught with pole-and-line (40%), compared with the larger-sized specimens caught with longlines (0%).
- For dolphinfish, the frequency of occurrence of MPD ingestion was similar for the similar-sized specimens caught with pole-and-line and with longlines.
- The ingested MPD items were micro–meso plastics, between 1 and 25 mm. While most ingested items were fragments, albacore also ingested line and skipjack also ingested sheets.
- The predatory fishes ingested light MPD items that float in sea water, but there were species-specific differences in their polymer composition: albacore contained more polypropylene and polyethylene, and skipjack contained more elastomers, characterized by a high percentage of ester plasticizers.
- Altogether, these results suggest that albacore and skipjack tunas ingest plastic of different types and polymers. Yet more research is needed to understand how differences in vertical distribution, foraging ecology and diet influence the MPD sampled by these predatory fish species.
5.
为了研究活性炭对金枪鱼酶解液脱色的最佳条件,本文利用活性炭对金枪鱼暗色肉酶解液进行处理,研究活性炭添加量、pH值、温度(T)和脱色时间(t)对脱色率和蛋白质损失率的影响,采用正交试验对脱色工艺进行优化,同时探究了活性炭脱色工艺对酶解液腥味物质和金属元素含量的影响.结果表明,金枪鱼暗色肉酶解液最佳脱色条件为活性炭添加量3%、pH值3.0、温度70℃、时间1h.该条件下脱色率为89.77%±0.77%,蛋白质损失率为13.47%±0.72%;脱色后酶解液挥发性物质含量降低了85.39%,其中三甲胺、己醛、壬醛等特征腥味物质显著降低;活性炭对Pb的吸附作用较明显,其吸附率为93.2%,而对其他金属元素的吸附率不大.研究表明,经过活性炭处理过的酶解液颜色浅,腥味低,具有一定的应用前景,可为酶解液的进一步利用提供依据. 相似文献
6.
7.
Elsa Beltran Alberta De Stefani Jennifer Stewart Luisa De Risio Victoria Johnson 《Veterinary ophthalmology》2010,13(3):184-189
Mast cell tumors are found in most organs and tissues with variable biologic behavior in dogs. This case illustrates the clinical and magnetic resonance imaging (MRI) findings in a dog with disseminated mast cell tumor infiltrating the sphenoid bones. A 6‐year‐old male neutered Greyhound presented with a 3‐day history of acute onset of blindness. General physical examination was normal. Neurological examination revealed mildly disorientated mental status, absent menace response in both eyes, bilaterally decreased vestibulo–oculocephalic reflexes and absent direct and consensual pupillary light reflex in both eyes. An electroretinogram indicated normal retinal function in both eyes. A lesion involving the middle and rostral cranial fossa was suspected. Hematology and serum biochemistry were normal except decreased urea (1.2 mmol/L). MRI of the head revealed heterogeneous signal intensity of the sphenoid bones on T2‐weighted images and loss of their normal internal architecture. Cerebrospinal fluid analysis was normal. Abdominal ultrasound revealed hepatosplenomegaly and mesenteric lymphadenopathy. Fine needle aspirates were taken from the jejunal lymph nodes and the spleen. Results were consistent with disseminated mast cell tumor. The owner declined any treatment and the dog was euthanatized. Postmortem examination confirmed disseminated mast cell tumor affecting multiple organs, including the sphenoid bones. To our knowledge, this is the first case describing MRI features of disseminated mast cell tumor affecting the sphenoid bones and causing acute onset of blindness in a dog. 相似文献
8.
9.
10.
K. Kumar I. V. Mogha H. P. Aithal Amarpal P. Kinjavdekar G. R. Singh A. M. Pawde H. C. Setia 《Veterinary research communications》2009,33(1):57-66
Survey radiographs of all the growing dogs aged up to 6 months, which were presented to the IVRI polyclinics during the 10 year
period were screened to study the determinants of bone mass, density and growth. On the basis of clinical history and radiographic
evaluation of long bones, the cases were categorized as normal or osteopenic. The relative cortical density (RCD), cortical
index (CI), diameter of bone at the distal metaphysis (DDFM) and the width of the growth plate (WFGP) were determined by taking
the femur as a model bone in German shepherd, Doberman and Spitz breeds of dogs at different age groups. The results showed
that the RCD was the least in 0–2 month old normal growing dogs in all the breeds. As the age advanced up to 6 months the
RCD increased 20–25%, and at 6 months, Spitz and Doberman showed significant increase (P < 0.05) in the RCD. In osteopenic
bones, RCD remained less (25–50%) than that of normal animals at all age groups, and at 2–6 months of age, RCD in osteopenic
bones was significantly lesser than in normal animals in GSD and Spitz breeds. The CI was also the least at 0–2 months of
age in normal dogs. The CI increased about 50% at 4–6 months of age in GSD and Spitz. Whereas in Dob., there was no appreciable
change in the CI at different age groups, and at 2–6 months it was significantly (P < 0.05) lesser than that of Spitz. In
osteopenic bones, the CI was 25–75% lesser than that of normal animals at different age groups, and at 4–6 months there was
significant difference (P < 0.05) between the normal and osteopenic bones in GSD and Spitz. The DDFM was the least in 0–2 month
old normal growing dogs, and as the age advanced, it increased 10–20% up to 6 months. However, no significant difference in
the DDFM was seen between breeds and also between the normal and osteopenic bones at different age groups. In normal animals,
the WFGP was highest in the early age, subsequently it reduced 50–75% and at 4–6 months there was significant decrease (P < 0.05)
in all the breeds of dogs. And at 4–6 months, there was significant (P < 0.05) difference in the WFGP between breeds, it was
the least in Spitz and maximum in Dob., suggesting faster growth plate closure in Spitz than in GSD and Dob. breeds. In osteopenic
bones, WFGP was generally more than in normal animals, and at 4–6 months (about 3–5 times more) there was significant difference
(P < 0.05) between the normal and osteopenic bones in all breeds, indicating that physeal closure may be delayed in osteopenic
bones. The results indicate that among different breeds Doberman breed has the least bone mass and may be more prone to osteopenia;
whereas Spitz has the strongest bone. 相似文献