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11.

Background

The diaphragm is the major respiratory muscle affected by Duchenne muscular dystrophy (DMD) and is responsible for causing 80% of deaths. The use of mechanical forces that act on the body or intermittent pressure on the airways improves the quality of life of patients but does not prevent the progression of respiratory failure. Thus, diseases that require tissue repair, such as DMD, represent a group of pathologies that have great potential for cell therapy. The application of stem cells directly into the diaphragm instead of systemic application can reduce cell migration to other affected areas and increase the chances of muscle reorganisation. The mdx mouse is a suitable animal model for this research because its diaphragmatic phenotype is similar to human DMD. Therefore, the aim of this study was to assess the potential cell implantation in the diaphragm muscle after the xenotransplantation of stem cells.

Methods

A total of 9 mice, including 3 control BALB/Cmice, 3 5-month-old mdx mice without stem cell injections and 3 mdx mice injected with stem cells, were used. The animals injected with stem cells underwent laparoscopy so that stem cells from GFP-labelled rabbit olfactory epithelium could be locally injected into the diaphragm muscle. After 8 days, all animals were euthanised, and the diaphragm muscle was dissected and subjected to histological and immunohistochemical analyses.

Results

Both the fresh diaphragm tissue and immunohistochemical analyses showed immunopositive GFP labelling of some of the cells and immunonegativity of myoblast bundles. In the histological analysis, we observed a reduction in the inflammatory infiltrate as well as the presence of a few peripheral nuclei and myoblast bundles.

Conclusion

We were able to implant stem cells into the diaphragm via local injection, which promoted moderate muscle reorganisation. The presence of myoblast bundles cannot be attributed to stem cell incorporation because there was no immunopositive labelling in this structure. It is believed that the formation of the bundles may have been stimulated by cellular signalling mechanisms that have not yet been elucidated.  相似文献   
12.
甘蔗内生菌分离鉴定及功能多样性研究   总被引:1,自引:0,他引:1  
为探究甘蔗内生菌多样性组成及相关特性,本研究采用稀释涂板法分离并结合形态观察和分子标记(gyrB,rpoB, ITS, 16S rDNA)进行鉴定。结果表明,从12个栽培品种(系)和5个野生种无性系的根、茎、叶组织中共分离到细菌589株、放线菌34株和真菌46株;细菌中固氮菌有41株,溶磷菌有98株,解钾菌有52株,对黄曲霉和禾谷镰刀菌具有拮抗作用分别有44株和35株。内生细菌分属21个属,其中芽孢杆菌属、伯克氏菌属、肠杆菌属和泛菌属为优势属;内生真菌分属于枝顶孢属、链格孢属、曲霉属、镰刀菌属、枝孢属等17个属,而放线菌仅为链霉菌属。具有潜在植物益生功能的菌株主要集中在芽孢杆菌属、伯克氏菌属、肠杆菌属、假单胞菌属、不动杆菌属、类芽孢杆菌属及泛菌属。本研究显示甘蔗栽培品种(系)和野生种无性系均含有丰富的内生菌资源,且栽培品种(系)所含内生菌在数量和多样性上均高于野生种无性系;12个栽培品种(系)间所分离到的内生细菌大部分相同,但也存在差异。通过初步的功能鉴定,筛选出一些具有应用潜力的益生微生物,为开发相应功能的生物菌剂奠定基础。  相似文献   
13.

The objective of this study was to evaluate the production, consumption, and energy balance parameters of primiparous 3/4 and 7/8 Holstein × Gir (HG) dairy cows fed two diets of differing energy levels during the postpartum period. At the beginning of the study, 28 days prepartum, the average weight of both genetic groups was 498?±?12 kg and body condition score (BCS) was 3.5?±?0.05. At the end of the study, 61 days postpartum, the 3/4 HG cows had higher weight and body condition scores than the 7/8 HG (456?±?8 and 429?±?8 kg and 3.13?±?0.03 and 2.94?±?0.03 BCS for 3/4 HG and 7/8 HG, respectively). Milk from cows fed the high-energy diet had higher percentages of fat, protein, lactose, and total dry extract than cows fed the low-energy diet. Cows fed the high-energy diet had higher net energy intake (95.3?±?1.9 vs. 88.1?±?2.1 MJ/day) and higher energy balance (3.64?±?2.13 vs ??6.02?±?2.30 MJ/day). The 3/4 HG cows displayed higher energy for maintenance (33.1?±?0.4 MJ/day) than the 7/8 HG (31.5?±?0.5 MJ /day). In conclusion, although the primiparous 3/4 HG were heavier than the 7/8 HG and had a higher body condition score, no differences in milk produced up to 60 days postpartum were observed. The higher energy diet during the postpartum period increased energy balance, resulting in higher production of milk fat, protein, and lactose.

  相似文献   
14.
The aim of this study was to evaluate the peak in luteinizing hormone (LH) and the pregnancy rate of sheep (Texel × Santa Inês) in the tropics using short‐ (6 days) and long‐term (12 days) progesterone protocols followed by artificial insemination (AI) both in and out of the breeding season. Experiment 1 was conducted within (IN) the breeding season (autumn, n = 36), and experiment 2 was conducted outside (OUT) of the breeding season (spring, n = 43). In each experiment, the sheep were divided into two groups (6 or 12 days) according to the duration of treatment with a single‐use progesterone release vaginal device (CIDR®, Pfizer, São Paulo, SP, Brazil), and blood samples were collected from 10 animals per group every 4 hr to measure the LH and progesterone concentrations. In the spring, the characteristics of the LH peak did not differ between groups; but in the autumn, there were differences between groups at the beginning (G‐6 IN: 36.44 ± 5.46 hr; G‐12 IN: 26.57 ± 4.99 hr) and end of the LH peak (G‐6 IN: 46.22 ± 7.51 hr; G‐12 IN: 34.86 ± 8.86 hr). The results showed alterations in the LH peak during the breeding season only in the sheep undergoing the short‐term protocol.  相似文献   
15.

Objective

To evaluate the effects of ketamine continuous rate infusions (CRI) at two dose rates on cardiovascular function and serum creatine kinase MB isoenzyme (CK-MB) and troponin I in healthy conscious dogs.

Study design

Experimental, prospective, crossover, randomized, blinded study.

Animals

Eight adult mixed-breed dogs, aged 6 ± 1 years and weighing 19 ± 8.6 kg (mean ± standard deviation).

Methods

Dogs were administered an intravenous bolus of ketamine (0.5 mg kg?1) followed by a ketamine CRI for 12 hours (20 μg kg?1 minute?1; treatment TC20 or 40 μg kg?1 minute?1; treatment TC40). Sedation, heart rate (HR), mean arterial pressure (MAP), electrocardiographic and echocardiographic parameters were evaluated at baseline (T0) and 1 (T1), 2 (T2), 4 (T4), 8 (T8), 12 (T12) and 24 (T24) hours after ketamine infusion started. Serum concentrations of CK-MB and troponin I were measured at baseline and 12, 24 and 48 hours after infusion started.

Results

HR increased over the first 4 hours, significantly at T1 in TC20 and at T4 in TC40 when compared with T0 (p < 0.05). MAP was significantly increased at T2 in TC40 when compared with TC20. Behavioral changes, such as stereotypical head movements and twitches, occurred within 4 hours in TC40. There were no significant changes in echocardiographic examinations in any dog when compared with baseline. There were no temporal changes in serum CK-MB activity either within or between treatments (p > 0.05). No troponin I was detected in any sample.

Conclusions and clinical relevance

No indication of myocardial injury resulting from ketamine infusion was detected in this study in healthy dogs. Further studies are needed to assess the ketamine infusion effects on antinociception and other organ function not evaluated in the present study.  相似文献   
16.
高效快速地分离提取高质量的线粒体DNA(mtDNA)是研究植物线粒体基因及其起源进化的重要前提。为获得高质量的mtDNA进行割手密资源的线粒体基因序列扩增及测序分析,本研究以割手密黄化苗为材料,通过简单差速离心分离得到线粒体,经DNaseⅠ消化处理,去除核DNA杂质得到较纯的线粒体,然后经过5%SDS和蛋白酶K充分裂解线粒体,利用饱和的苯酚/氯仿(1:1)和氯仿两次抽提除去蛋白质,并经过RNase A的消化处理除去RNA,无水乙醇沉淀等一系列操作得到mtDNA。所提取的mtDNA样品经紫外吸收光度测定,琼脂糖凝胶电泳和PCR扩增分析其浓度和纯度,结果表明利用该方法提取的mtDNA纯度高,完全能满足后续PCR分析及分子克隆测序的要求。该方法不仅DNA提取纯度高,操作简单、快速经济,可为今后开展甘蔗及其各野生种的研究提供技术支持。  相似文献   
17.
Objective – To describe the use of IV and oral mycophenolate mofetil (MMF) as adjunctive therapy in 3 dogs with severe generalized myasthenia gravis.
Case Series Summary – Three dogs suffering from severe generalized myasthenia gravis as confirmed by acetylcholine antibody titers were treated with MMF as part of their treatment regimens. All 3 dogs had radiographic evidence of megaesophagus and suffered from severe regurgitation. Each dog was initially treated with pyridostigmine and supportive agents. When clinical remission was not achieved, IV MMF was administered to all dogs. Signs of clinical remission were apparent within 48 hours and all dogs were later maintained on oral MMF following resolution of regurgitation.
New or Unique Information Provided – This is the first report of the use of IV MMF as adjunctive treatment in dogs with severe generalized myasthenia gravis. Outcome was favorable in all 3 dogs and no adverse effects were noted from the MMF.  相似文献   
18.
探索内生菌对甘蔗抗旱能力的影响,以期为开发利用甘蔗内生菌抗旱性功能菌株提供理论依据和技术支撑.以课题组前期分离鉴定的6株甘蔗内生菌为供试菌株,甘蔗品种'ROC22'幼苗接种7天后进行干旱胁迫,然后取完全展开的第一叶叶片测定相关生理指标.结果 表明,E3、09和YC89均有较高的ACC脱氨酶活性,不同甘蔗内生菌菌株对甘蔗...  相似文献   
19.
20.
Asian grapevine leaf rust (AGLR) causes severe crop losses in Brazilian viticulture, mainly in latitudes <25°S. The purpose of this study was to identify the pathogen(s) involved with AGLR in Brazil, based on phylogenetic and morphological analysis and pathogenicity tests. In total, 56 monouredinial isolates from six Brazilian states were identified using the internal transcribed spacer 2 and the large subunit rRNA gene D1/D2 regions. All 50 isolates from the south-central region were classified as Neophysopella tropicalis, and the other six isolates from the north-east region as Neophysopella meliosmae-myrianthae. This result provides evidence that two pathogen introductions from different sources may have occurred in the country. For both species, paraphyses were cylindrical, incurved, aseptate, and hyaline, while urediniospores were short-pedicellate, obovoid or obovoid-ellipsoid, with the wall colourless or pale yellowish, evenly echinulate. Representative isolates from both species caused typical AGLR symptoms on Vitis vinifera 'Merlot' and V. labrusca 'Niagara Rosada'. Overall, regardless of the Neophysopella species, isolates caused similar leaf disease severities. Higher disease severity was observed in Niagara Rosada (average of 40.3% of diseased leaf area) compared to Merlot (20.5%). This study reports, for the first time, the characterization of Neophysopella species associated with AGLR in Brazil.  相似文献   
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