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邵晓阳 《水产学报》2004,28(4):438-442
用连续切片的方法对患有红体病的青虾进行组织病理学研究,结果表明患病青虾鳃部、肌肉组织和肝胰腺部位病症比较明显,不同患病阶段组织变形差异显著。鳃片细胞在患病初期表现为胞质收缩,后期则细胞膨胀破裂。细胞内物质外溢,细胞边缘界限不完整;肌肉组织在后期出现肌纤维束之间间隙,且部分肌纤维有断裂的现象;中期肝小叶间隔出现空隙和腺细胞变形,在后期则表现为小叶溃烂。造成青虾因红体病死亡的原因,初期主要是因为鳃片的组织病变导致呼吸困难,进而造成青虾生理异常;后期主要是因为肝胰脏的溃烂造成消化功能全面丧失。  相似文献   
23.
“红肉病”文蛤的组织病理学   总被引:9,自引:0,他引:9  
任素莲 《水产学报》2003,27(5):462-467
利用组织学和组织化学方法,在光镜水平下研究了患“红肉病”文蛤(Meretrix meretrix Linnaeus)的组织病理学变化特征。结果显示,患病文蛤的病理学变化主要表现为组织结构紊乱,上皮膨大、脱落,鳃、外套膜、消化盲囊等组织发现异常结构及寄生物,如嗜碱性的包涵体、嗜酸性颗粒及寄生性原生动物等。另外,组织化学研究结果显示,病蛤在糖含量、磷酸酶活性等方面也有明显变化,表现为消化盲囊、肠等部位吸收细胞内糖含量增加。消化盲囊、消化管各处酸性磷酸酶(ACP)活性减弱,碱性磷酸酶活性(AKP)增强。鳃组织ACP活性增强,AKP活性减弱等。  相似文献   
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Amoebic gill disease (AGD) affects the marine culture phase of Atlantic salmon, Salmo salar L., in Tasmania. Here, we describe histopathological observations of AGD from smolts, sampled weekly, following transfer to estuarine/marine sites. AGD was initially detected histologically at week 13 post-transfer while gross signs were not observed for a further week post-transfer. Significant increases (P < 0.001) in the proportion of affected gill filaments occurred at weeks 18 and 19 post-transfer coinciding with the cessation of a halocline and increased water temperature at the cage sites. The progression of AGD histopathology, during the sampling period, was characterized by three phases. (1) Primary attachment/interaction associated with extremely localized host cellular alterations, juxtaposed to amoebae, including epithelial desquamation and oedema. (2) Innate immune response activation and initial focal hyperplasia of undifferentiated epithelial cells. (3) Finally, lesion expansion, squamation-stratification of epithelia at lesion surfaces and variable recruitment of mucous cells to these regions. A pattern of preferential colonization of amoebae at lesion margins was apparent during stage 3 of disease development. Together, these data suggest that AGD progression was linked to retraction of the estuarine halocline and increases in water temperature. The host response to gill infection with Neoparamoeba sp. is characterized by a focal fortification strategy concurrent with a migration of immunoregulatory cells to lesion-affected regions.  相似文献   
26.
Pathological changes in cultured tiger puffer, Takifugu rubripes , with emaciation disease in Kyushu, Japan were studied histologically. In most cases, diseased fish were heavily infected with at least one of three myxosporeans ( Myxidium fugu , Myxidium sp. and Leptotheca fugu ) and two unidentified hyperparasitic microsporeans, attached to, or in, the intestinal epithelium. Myxidium fugu attached to the surface of the epithelium, caused no noticeable effects on the host tissue, irrespective of its infection with the hyperparasite. Myxidium sp., which proliferated in the epithelium, induced severe pathological changes including accumulation of cell debris between the epithelium and lamina propria and resultant detachment of the epithelium. Leptotheca fugu, another histozoic myxosporean, induced degeneration of the epithelium, associated with massive infiltration of macrophages into the epithelium to encapsulate parasites. When L. fugu was infected with its hyperparasitic microsporean, shortened villi were also observed. This is probably because passage of macrophage-parasite aggregates through the basement membrane of the epithelium severely damaged the epithelial structure. It is evident histologically that, unlike epicellular M. fugu , histozoic Myxidium sp. and L. fugu with or without hyperparasitic microsporeans, were highly pathogenic to host fish. This strongly suggests that they are causative agents of the emaciation disease.  相似文献   
27.
甜菜夜蛾感染白僵菌、绿僵菌后的病症及组织病理学变化   总被引:5,自引:0,他引:5  
甜菜夜蛾感染白僵菌和绿僵菌后,虫体颜色及外部形态均发生相应变化。其组织切片观察研究表明:两种供试菌株的致病过程基本一致,只在侵染速度上有所差异:绿僵菌侵染速度较快,而且其破坏裂解组织的程度远大于白僵菌。白僵菌菌株015处理24 h后肠道内未见萌发的孢子,组织没有发现变化;48 h,附着于甜菜夜蛾体壁外的孢子开始萌发;72 h体腔内明显的菌丝段,各组织器官均受到感染,之后进入体内的菌丝不断增殖,脂肪体、肌肉组织、消化道发生病变解体;120 h后,菌丝突破虫体,在体外形成菌丝层。较之于绿僵菌菌株060,72 h时菌丝充满血腔,肠壁细胞也受到严重侵染,肠腔内出现菌丝,部分菌丝突出体表,菌株086,96 h时各组织均解体。  相似文献   
28.
Southern populations of the European minnow fromremote oligotrophic mountain lakes along an Alpinenorth-south transect accumulated more p,p DDE andPCBs than northern populations. As these semi-volatileorganochlorines predominantly evaporate in warmcountries, higher rates of condensation (deposition)are assumed to occur in the southern slopes of theAlps. The higher accumulation of lead and cadmium insouthern population is rather attributed to geogenicand specific environmental impacts than to atmosphericdeposition. Increasing liver ratios of [glutathionedisulfide]/[glutathione], a potential indicator foroxidative stress, from north to south reflect thegenerally higher toxic load at remote sites at thesouthern edge of the Alps. However, histopathologicalchanges in the liver did not correlate withaccumulated toxicants indicating that deposition doesnot lead to severe lesions but induces specificmechanisms for detoxification.  相似文献   
29.
锈粉宁浸种对小麦白粉病菌侵染叶部过程的影响   总被引:1,自引:0,他引:1  
供试小麦种子用50%锈粉宁500和1000倍药液浸种,出苗后一叶期用小麦白粉病菌(Erysiphe graminis f.sp.tritici)接种。用特种蛋白质染料柯马氏亮兰(Coomassie Brilliant Blue R-250)叶片快速透明染色法系统研究了锈粉宁对小麦白粉病菌侵染叶部过程的影响。结果表明,在浸种植株叶片中,小麦白粉病菌从分生孢子萌发到吸器形成严重受抑制,接种48h 后,附着胞、菌丝分枝和吸器不再形成,96h 后分枝菌丝变形消解。这些组织病理学的特征表明,锈粉宁主要是通过抑制小麦白粉病菌菌丝的分枝和扩展来减少吸器形成的数量,达到控制病菌扩展的目的。  相似文献   
30.
研究了265头青年猪1 060个关节(附关节和腕关节各530个)骨软骨病的病理组织学变化.肉眼观察主要表现为患部关节软骨变色、充血,关节面粗糙、裂开、糜烂或凹陷,并根据其损伤程度进行分类,即正常、轻度、中度和严重,分别占21.7%、33.3%、29.0%、16.0%.显微观察特征为关节软骨局部增厚,软骨细胞增生、肥大;在一些区域软骨细胞变性、坏死,坏死区易形成裂隙;骨质内形成软骨岛.结论:青年猪有很高的骨软骨病发病率,后肢比前肢严重,并表现典型的骨软骨病组织病理学特征.  相似文献   
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