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381.
BACKGROUND: Inborn errors of metabolism impose a significant genetic burden on purebred dogs and cats. The glycogen storage diseases are a category of such disorders that are typed by enzyme analysis, but deoxyribonucleic acid (DNA) based carrier tests are needed for definitive, noninvasive diagnosis and to prevent at-risk matings. HYPOTHESIS: Glycogen storage disease type IIIa (GSD IIIa) is caused by a mutation of the glycogen debranching enzyme gene (AGL) in Curly-Coated Retrievers (CCR). ANIMALS: Two CCR exhibiting episodic exercise intolerance, collapse, and lethargy, and related dogs were studied. METHODS: Structure and amount of glycogen isolated from tissue biopsy specimens was determined by enzymatic digestion, and activities of enzymes of glycogen metabolism were measured. The 33 AGL coding exons and flanking splice sites of an affected dog were amplified by polymerase chain reaction and sequenced. RESULTS: Debranching enzyme activity was undetectable in liver and skeletal muscle of affected dogs, and accumulated glycogen had absent or short outer chains of alpha1, 4-linked glucose. A single adenosine (A) deletion in AGL exon 32 of affected dog genomic DNA predicted a frame-shift and truncation of the protein product by 126 amino acid residues. The mutation was homozygous in affected dogs and heterozygous in both parents. In addition, the deletion mutation was heterozygous in 16 or not detected at all in 31 related but clinically normal CCR. CONCLUSIONS AND CLINICAL IMPORTANCE: GSD IIIa in CCR is an autosomal recessive trait caused by mutation of AGL. A DNA sequence-based carrier test was developed, and carriers were identified in the United States, New Zealand, Australia, and Finland.  相似文献   
382.

Background

Calf output is a key element in determining the profitability of a suckler beef enterprise. Infectious agents such as Bovine Virus Diarrhoea (BVD) virus, colostrum management and parasitic challenge can all affect calf output. Prior to the national BVD eradication programme, there was little published information on either the prevalence or effect of BVD in Irish beef herds. There is little published information on colostrum management practices in Irish commercial beef herds and there have also been few studies published on the prevalence of liver fluke or rumen fluke infection in Irish beef herds. Sixteen farms participating in the Teagasc/Farmers Journal BETTER farm beef programme were used in this study. Fourteen herds were screened for the presence of BVD virus in 2010 using RT-PCR. In 13 herds, blood samples were collected from calves (2–14 days of age) in November 2011 - April 2012 to determine their passive immune status using the zinc sulphate turbidity (ZST) test, while in 12 herds, blood and faecal samples were taken in order to determine the level of exposure to gastrointestinal and hepatic helminths.

Results

The overall prevalence of BVD virus-positive cattle was 0.98% (range 0 - 3% per herd, range 0.6 - 3.0% per positive herd). Eighteen of the 82 calves (22%) sampled had ZST values less than 20 units (herd mean range 17.0 – 38.5 units) indicating a failure of passive transfer. The overall animal-level (herd-level) prevalence of liver fluke and rumen fluke infection in these herds was 40.5% (100%) and 20.8% (75%), respectively.

Conclusions

The potential costs associated with the presence of animals persistently infected with BVD virus through the increased use of antibiotics; the rate of failure of passive transfer of colostral immunoglobulins and the high prevalence of liver fluke infection in these herds highlight that some Irish suckler beef farms may not be realizing their economic potential due to a range of herd health issues. The use of farm-specific herd health plans should be further encouraged on Irish suckler beef farms.  相似文献   
383.
AIM: To investigate the changes of histone modifications during the activation of primarily cultured rat hepatic stellate cells (HSCs) and the relationship between histone modification patterns and α-smooth muscle actin (α-SMA) expression, and to explore the roles of histone modifications in the activation of HSCs. METHODS: The rat HSCs were isolated by in situ perfusion of collagenase combined with density gradient centrifugation, cultured in vitro and identified by immunofluorescence staining. The morphological features of the cells were observed under inverted microscope. The changes of desmin and α-SMA during the activation of HSCs were detected by immunofluorescence staining and Western blotting. The levels of histone 3 lysine 4 dimethylation (H3K4me2), histone 3 lysine 9 dimethylation (H3K9me2), histone 3 lysine 9 acetylation (acH3K9) and histone 4 lysine 12 acetylation (acH4K12) in quiescent HSCs and activated HSCs were determined by Western blotting.RESULTS: The morphology of HSCs shifted from a quiescent phenotype to highly activated myofibroblast during the culture. Immunofluorescence staining and Western blotting showed that the expression levels of α-SMA and desmin were increased over time and reached maximum at 15 d. According to the results of cell morphology and immunofluorescence staining, the cells cultured for 24 h and 15 d were quiescent and activated HSCs, respectively. Compared with quiescent HSCs, there were higher H3K4me2 and lower H3K9me2, acH3K9 and acH4K12 modification levels in activated HSCs (P<0.01). CONCLUSION: Histone modifications show anomalous expression during the activation of primarily cultured rat HSCs. Histone modifications may contribute to the transdifferentiation of HSCs and the development of hepatic fibrosis.  相似文献   
384.

Background

Biopsy of the liver evaluates a small portion of tissue, with inferences made to the entire organ. The method and number of biopsies obtained are tempered by consideration of the risks and benefits. Recommendations often include biopsy of more than one liver lobe, although the consistency of histopathology among lobes in dogs is unknown.

Hypothesis/Objectives

To describe the distribution of histopathologic abnormalities between liver lobes. We hypothesized that discordant results would be evenly distributed among all liver lobes.

Animals

Seventy dogs undergoing necropsy.

Methods

Prospective study. Liver samples were obtained from all lobes. A primary diagnosis was assigned to each liver sample based on the predominant histopathologic abnormality.

Results

In this population of dogs, biopsy of at least 2 liver lobes identified the predominant histologic abnormality in 98.6% of the cases. Ten (14%) of the dogs had ≤3 lobes in agreement and could not be assigned a predominant diagnosis. The same diagnosis was present in 6/6 lobes in 39 (56.5%) dogs, 5/6 lobes in 10 (14.5%) dogs, 4/6 lobes in 10 (14.5%) dogs, 3/6 lobes in 7 (10.1%) dogs, and 2/6 in 3 (4.3%) dogs. The number of discordant results did not differ between the liver lobes.

Conclusion and Clinical Importance

The likelihood of obtaining a sample that is reflective of the predominant histologic abnormality in the liver is increased when multiple liver lobes are biopsied.  相似文献   
385.

Background

Serum bile acid concentrations (SBA) and a histopathological biopsy score [Equine Vet J 35 (2003) 534] are used prognostically in equine hepatic disease.

Hypothesis

Histopathologic features and scores, but not SBA, differ between survivors and nonsurvivors and correlate with histopathologic evidence of hepatic inflammation and fibrosis.

Animals

Retrospective study. Records (1999–2011) of horses with hepatic disease diagnosed by biopsy and with concurrent measurements of SBA.

Methods

Retrospective cohort study. Biopsies were examined for inflammatory cell infiltration including type and distribution, fibrosis, irreversible cytopathology affecting hepatocytes, hemosiderin, or other pigment deposition and bile duct proliferation. SBA, histopathological findings and a histological score [Equine Vet J 35 (2003) 534] were compared between short‐ (survival to discharge) and long‐term (>6 months) survivors and correlations between SBA and histopathological findings investigated.

Results

Of 81 cases 90% survived short‐term and 83% long‐term. Short‐term and long‐term nonsurvival were associated with SBA (P = .009; P = .006), overall (P = .001; P = .002) and parenchymal (short‐term only; P = .01) inflammation, portal and bridging fibrosis (all P < .001), apoptosis or single cell necrosis (P < .001; P = .008), hemosiderin deposition in hepatocytes (P = .011; P = .028), biliary (both P < .001), vascular (P = .003; P = .045) and endothelial (P < .001; P = .02) hyperplasia, nucleic changes (P = .004; P < .001) and the histopathological score (both P < .001). SBA were significantly and positively correlated with overall (P = .001), parenchymal (P < .001) and portal (P = .004) inflammation and portal (P = .036) and bridging (P = .002) fibrosis.

Conclusions and Clinical Importance

SBA, histopathological findings and scores differ between survivors and nonsurvivors. SBA concentrations are associated with inflammation and fibrosis suggesting interference with hepatic function. A histopathological score >2 and, less so, SBA >20 μmol/L are specific but not sensitive indicators of nonsurvival.  相似文献   
386.
Kotoky J  Dasgupta B  Sarma GK 《Fitoterapia》2008,79(4):290-292
Different extracts of the leaves of Leucas lavendulaefolia were tested against D-galactosamine (D-GalN) induced liver toxicity in rats. The methanol extract (100 mg/kg, p.o.) which exhibited significant hepatoprotective activity seems to support the claim of folk medicine.  相似文献   
387.
为探索大豆异黄酮对过氧化氢(H_2O_2)致肝细胞损伤的保护作用,以H_2O_2损伤Chang Liver细胞建立肝细胞氧化应激损伤模型,并以10,20和40 mg·L~(-1)大豆异黄酮进行干预。采用四甲基偶氮唑盐比色(MTT)法检测肝细胞存活率;以微板法检测细胞培养液中乳酸脱氢酶(LDH)、谷丙转氨酶(ALT)、谷草转氨酶(AST)活性和肝细胞超氧化物歧化酶(SOD)活性,以及肝细胞还原型谷胱甘肽(GSH)和丙二醛(MDA)含量;采用蛋白印迹技术检测肝细胞核因子-E2相关因子2(Nrf2)蛋白含量。在10~40 mg·L~(-1)范围内,大豆异黄酮对Chang Liver细胞不显示细胞毒作用。300μmol·L~(-1)H_2O_2刺激后,模型组肝细胞存活率与正常组比较下降,细胞外液中ALT、AST、LDH水平上升,说明Chang Liver细胞损伤显著;而模型组肝细胞中SOD和GSH水平与正常组比较下降,丙二醛水平上升,说明模型组Chang Liver细胞氧化应激增强。大豆异黄酮可剂量依赖性地提高Chang Liver细胞存活率,降低ALT、AST、LDH向细胞外液的释放;降低细胞MDA水平,升高细胞SOD和GSH水平,增高核中Nrf2蛋白水平。研究结果显示大豆异黄酮对H_2O_2致肝细胞氧化应激损伤具有保护作用。  相似文献   
388.
用三水平棉籽饼、菜籽饼的饲粮饲喂蛋鸡300d,结果表明,各组饲料配方对鸡肝中7种微量元素含量的影响无显著差异;三水平棉籽饼对鸡肝锰有显著影响,低、中、高水平肝锰分别为5.97ppm,5.85ppm,8.05 PPm;三水平菜籽饼对肝硒有显著影响,低、中、高水平肝硒分别为0.708PPm,0.696ppm,0.792ppm,SGOT与肝铁之间呈强正相关(r=0.7206)。  相似文献   
389.
AIM:To investigate the effect of urantide on the liver function and histomorphology in the rats with atherosclerosis (AS).METHODS:The AS Wistar rat model was induced by intraperitoneal injection of vitamin D3 (VD3) and feeding with high-fat diet. The rats were randomly divided into normal control group, AS model group, positive medicine group and urantide group. The liver function indexes of the rats were measured by biochemical test, and the pathological changes of the aorta and liver of the rats were observed by hematoxylin-eosin (HE) staining. The mRNA expression of urotensin Ⅱ (UⅡ) and GPR14 at mRNA and protein levels in rat livers was determined by RT-qPCR and Western blot. RESULTS:The levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), γ-glutamyltransferase (γ-GT), lactate dehydrogenase (LDH), total bilirubin (TBIL), indirect bilirubin (IBIL) and alkaline phosphatase (ALP) in AS model group were significantly increased compared with normal control group (P<0.05). The above indexes in urantide group were remarkably decreased compared with AS model group (P<0.05). No change of the levels of direct bilirubin (DBIL), total protein (TP), globulin (GLB) and albumin (ALB) in each group was observed. Urantide postponed hepatocyte fatty degeneration and repaired hepatocyte injury in the AS rats. Compared with normal control group, the mRNA and protein levels of UⅡ and GPR14 in the liver were significantly increased in AS model group (P<0.05). With the prolongation of dosing time, the mRNA and protein levels of UⅡ and GPR14 in the liver were significantly decreased in urantide group compared with AS model group (P<0.05). CONCLUSION:Urantide significantly attenuates the liver damage caused by liver fatty degeneration in AS rats.  相似文献   
390.
AIM: To investigate the adaptive characteristics of mitochondria in plateau pikas at different altitudes. METHODS: According to the altitudes of the capture area, plateau pikas were divided into 4 300 m group (Mado Star Sea, n=6) and 2 900 m group (Laoji Mountain South, n=6). The red blood cells and hemoglobin of the animals in 2 groups were measured. The levels of mitochondrial oxidative phosphorylation (OXPHOS) and fatty acid oxidation (FAO) in the liver and skeletal muscle, and mitochondrial H2O2 production level in the skeletal muscle were determined by high-resolution mitochondrial respirometer. RESULTS: The hemoglobin of the plateau pika in 4 300 m group was significantly lower than those in 2 900 m group. The liver state 4 respiration rate of mitochondrial respiratory chain complex I (CI-LEAK), mitochondrial respiratory chain complex I state 3 respiration rate (CI-OXPHOS) and respiratory chain complex I+Ⅱ state 3 respiration rate(CI+Ⅱ-OXPHOS), electron transfer capacity of respiratory chain complex I+Ⅱ (CI+Ⅱ-ETS), the electron transport capacity of the respiratory chain complex Ⅱ (CⅡ-ETS) in 2 900 m group were increased, and the coupling efficiency was decreased compared with 4 300 m group (P<0.05). The skeletal muscle CI-LEAK,CI+Ⅱ-OXPHOS and CI+Ⅱ-ETS were higher than those in 4 300 m group. Mitochondrial state 4 respiration rate with palmitic acid carnitine and malate as substrates (FAO-LEAK) of liver and skeletal muscle in 2 900 m group were increased compared with 4 300 m group. The skeletal muscle with palmitic acid carnitine as a substrate for fatty acid metabolism state 3 respiratory rate (FAO-OXPHOS) was increased in 2 900 m group compared with 4 300 m group. The H2O2/O2 flow ratio (ΔH2O2) in 2 900 m group was lower in state 4 respiration rate of mitochondrial respiratory chain complex I (LEAK), state 3 of mitochondrial respiratory chain complex I (OXPHOS), state 3 of mitochondrial respiratory chain complex I+Ⅱ (OXPHOS*) and electron transfer capacity of respiratory chain complex I+Ⅱ (ETS) than 4 300 m group. CONCLUSION: Plateau pikas with different altitudes have different mitochondrial adaptation characteristics.  相似文献   
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