首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   120篇
  免费   2篇
林业   4篇
农学   1篇
基础科学   1篇
  10篇
综合类   6篇
水产渔业   18篇
畜牧兽医   71篇
植物保护   11篇
  2022年   6篇
  2021年   8篇
  2019年   1篇
  2018年   2篇
  2017年   1篇
  2016年   8篇
  2015年   16篇
  2014年   11篇
  2013年   9篇
  2012年   5篇
  2011年   6篇
  2010年   1篇
  2009年   7篇
  2008年   3篇
  2007年   5篇
  2006年   6篇
  2005年   2篇
  2004年   3篇
  2003年   3篇
  2002年   6篇
  2001年   3篇
  2000年   3篇
  1998年   1篇
  1993年   1篇
  1992年   1篇
  1990年   1篇
  1963年   1篇
  1959年   1篇
  1957年   1篇
排序方式: 共有122条查询结果,搜索用时 31 毫秒
91.
A cardiac mass (3 × 5 × 3 cm) was detected at the base between the right auricular wall and right vena cava of a slaughtered 6-month-old female mixed-breed pig during a meat inspection. The tumor comprised infiltrative prominent interweaving fascicles of Schwann cells with Verocay bodies. Moreover, the ganglion cells were scattered or aggregated throughout the neoplastic tissue. The ganglion and Schwann cells had neither cellular atypism nor mitosis. On the basis of the bearing site as well as the morphological and immunohistochemical features, this is the first case of a cardiac ganglioneuroma in a pig.  相似文献   
92.
Because heavy metals cause various health hazards, we studied biosorption by Weissella viridescens MYU 205. MYU 205 showed high biosorption for Cd (II) and Hg (II) and was low for Zn (II). The Hg (II) biosorption rate was high at about 80%. Different biosorptions were shown for each metal after successive incubation. About 20% of the Zn (II) biosorption was observed after 3 h. Cd (II) biosorption increased in a time‐dependent manner until 3 h, then gradually decreased. Hg (II) was immediately sorbed at 79.6 ± 4.7% and decreased at 3 h to 52.9 ± 2.6%, and then gradually increased to 77.8 ± 3.6%. Using heat‐killed cells, the rate of biosorption of Zn (II) and Cd (II) decreased whereas Hg (II) tended to increase. The metal resistance was high, that is Zn (II) > Cd (II) > Hg (II); while the affinity was opposite where MYU 205 showed high affinity to Hg (II) and low affinity to Zn (II). Our data shows lactic acid bacteria may be powerful heavy metal sorbents for detoxification.  相似文献   
93.
A novel angiotensin‐converting enzyme (ACE) inhibitory peptide was isolated and purified from chicken bone extract by enzymatic digestion. The peptide was defined as an ACE inhibitor, and it demonstrated antihypertensive activity following oral administration to spontaneously hypertensive rats (SHRs). The results of this study suggest that peptides derived from an extract of chicken bones, administered orally, have the ability to reduce the blood pressure of SHRs significantly over a short period of time (3 h). Moreover, the blood pressure then remains low for 3 h. This peptide derived from chicken bones may therefore have great value as a short‐term remedy for chronic conditions such as high blood pressure. The amino acid sequence of the peptide was YYRA (Tyr‐Tyr‐Arg‐Ala), which was the origin of the Ig heavy chain V region (27–30 position). The IC50 value of its synthetic peptide was 33.9 μg/mL. We suggest that the ACE inhibitory and antihypertensive peptides derived from chicken bone extract may contribute to develop physiologically functional foods or improve food functionality.  相似文献   
94.
The property of hydrophilic polymers capable absorbing huge volumes of water led to many practical applications of these new materials in arid regions for improving the water retention in sandy soils. Effects of four carboxymethylcelluloses (CMC), mixed at various rates with the sandy soil, on the water-holding capacity and hydraulic conductivity (KS ) when leached with distilled water (simulating rain), tap water, and saline water were evaluated. The maximum water absorption of CMCs ranged between 80 and 100 kg ? kg-1 of polymer; however, the absorbent swelling capacity decreased significantly with increasing the salt concentration in the solution. The water absorption capacity of CMCs decreased significantly when incorporated in the sandy soil compared to that of the absorbent alone. Application of CMC increased significantly the available water content up to 3 ± 0.5 times. All soils treated with CMCs showed a significant lower in KS compared to the control soil. Meanwhile, KS was found increased with increasing the salt concentration in the leaching solution. This understanding of characteristics of the absorbents and the interactions among absorbents, soil, and irrigation water quality would be of help in water management of sandy soil.  相似文献   
95.
A cat was presented with depression and anorexia. The complete blood cell count (CBC) revealed non-regenerative anemia (PCV, 8.5%), marked thrombocytopenia (2,400/µl), and leukocytosis (32,090/µl). In the peripheral blood, proliferation of blast cells (85%; 27,276/µl) and basophils (7.7%; 2,460/µl) was observed. Bone marrow aspirate showed hyperplasia with 8.8% blasts and 90.2% basophils of all nucleated cells. The blast cells were negative for myeloperoxidase staining and positive for alpha-naphthol butyrate esterase staining, indicating the agranular blasts are monoblasts. Thus, acute monoblastic leukemia (M5a) with chronic basophilic leukemia was diagnosed. Basophils accounted for more than 40% of the bone marrow, and we diagnosed secondary basophilic leukemia. Secondary basophilic leukemia should be included in the differential list when abnormal basophil increases are observed in feline bone marrow.  相似文献   
96.
Kohno  Yuuki  Satoh  Hiroshi  Iguchi  Akiko  Nagai  Hiroshi 《Fisheries Science》2009,75(4):1049-1054
A 20-kDa protein toxin (bandaporin) was isolated from the sea anemone Anthopleura asiatica (Actiniidae) using the precipitation of ammonium sulfate saturation, and ion-exchange and gel-permeation chromatographies. Bandaporin showed potent hemolytic activity (EC50 value: 8.8 ng/ml to 0.8% suspension of sheep red blood cells) and lethal toxicity to crayfish (LD100 value: 0.58 mg/kg). The hemolytic activity of bandaporin was inhibited specifically by sphingomyelin. Eight other tested membrane lipids, including cholesterol, and gangliosides GM1 and GM2, did not inhibit bandaporin hemolytic activity. Antimicrobial and phospholipase A2 (PLA2) activities were not detected in bandaporin. The complementary DNA (cDNA) encoding bandaporin was sequenced and the deduced amino acid sequence of bandaporin revealed that this actinoporin had not been previously characterized. Actinoporins are cytolytic peptide toxins that are widely distributed in Actiniidae and Stichodactylidae sea anemones. This study was the first characterization of an actinoporin from a sea anemone of the genus Anthopleura.  相似文献   
97.
98.
We investigated the reflectances of black plant fragments in melanic Andisols and of fresh charcoal produced during modern grassland and forest fires with the aim of clarifying the origin of fragments in melanic Andisols. The reflectance values of most Andisol plant fragments were less than 2%; all values were below 3%. These values are considered to have formed at temperatures of at least 200°C, indicating that these fragments are charcoal fragments. The reflectances of the fragments in melanic Andisols were similar to those of grass charcoal from grassland fires rather than wood charcoal produced during forest fires. This finding indicates that most charcoal fragments in melanic Andisols are the product of grassland fires. The small difference between the reflectance values of the charcoal fragments in the Andisols and the grass charcoal is possibly derived from the fact that charcoal fragments with lower reflectance are more likely to be retained in the soil than fragments with higher reflectance values.  相似文献   
99.
A critical component of many releasing projects is the identification and subsequent implementation of optimal release strategies that can decrease post-release predation mortalities. We performed laboratory experiments to investigate whether acclimation to shelters affects the post-release survival of hatchery-reared black-spot tuskfish Choerodon schoenleinii in the presence of a reef-resident predator, the white-streaked grouper Epinephelus ongus. Tuskfish were exposed to groupers under three different experimental conditions/treatments: (1) acclimation of fish to shelters prior to their exposure to groupers; (2) no acclimation of fish to shelters, but with shelters available during their exposure to groupers; (3) fish not acclimated to shelters and no shelters available during their exposure to groupers. Tuskfish that were acclimated to shelters utilized shelters more frequently than did non-acclimated fish, and the survival rate of acclimated fish was higher than those of fish in the other treatments. These results suggest that pre-release acclimation to shelters improves the post-release survival of hatchery-reared black-spot tuskfish.  相似文献   
100.
A large size (400 kDa) non-collagenous protein was detected as a major component in the extract, with neutral salt solution, from the dermis of sea cucumber Apostichopus armata. On SDS-PAGE analysis, the 400 K component shifted to a lower molecular weight component (about 200 K) by reduction with 2-mercaptoethanol, and they were both reactive for periodic acid-Schiff (PAS) reaction staining. From these results, this protein was suggested to be a glycoprotein consisting of disulfide-bonded two subunits with almost equal molecular weight (200 K). In addition to relatively high contents (>100/1,000 residues) of aspartic and glutamic acids, cysteine was also detected (6.1/1,000 residues) in amino acid analyses of this protein partially purified by anion-exchange column chromatography. These combined results suggest the structural similarity of the 400 K component to fibronectins from other vertebrate and invertebrate animals.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号