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1.
目的:观察持续被动运动(CPM)和补充一氧化氮(NO)供体——硝酸甘油(NG)对兔骨关节炎(OA)模型中软骨基质金属蛋白酶-1(MMP-1)和MMP-13表达以及NO含量的影响,探讨CPM下调MMPs的可能机制。方法:30只3~4月龄雄性新西兰大白兔,其中6只进行假手术作为正常对照组(NC组),另外24只建立膝关节OA模型,术后随机分为4组,即OA对照组(OA组)、OA硝酸甘油给药组(NG组)、OA持续被动运动组(CPM组)、OA持续被动运动+硝酸甘油给药组(CPM+NG组),每组各6只。NC组和OA组不作处理,NG组给予NG软膏膝关节局部涂抹,CMP组在CPM训练仪上进行膝关节持续被动运动,CMP+NG组即在运动干预的同时给予NG局部涂抹。4周后取各组软骨组织,硝酸还原酶法测定NO含量,HE染色观察软骨形态学变化并进行Mankin''s评分,实时荧光定量PCR(RQ-PCR)检测MMP-1和MMP-13 mRNA水平,免疫组织化学法测定MMP-1和MMP-13蛋白表达量。结果:NO含量、Mankin''s评分以及MMP-1和MMP-13 mRNA和蛋白水平在OA组明显高于NC组(P<0.01),NG组高于OA组(P<0.01),CPM组低于OA组和NG组(P<0.01),CPM+NG组低于NG组(P<0.01),但高于CPM组(P<0.01)。结论:CPM通过抑制软骨细胞NO合成下调MMP-1和MMP-13表达,进而对软骨细胞起保护作用。  相似文献   
2.
以史氏鲟鱼软骨为原料,按碱提酶解醇沉的工艺流程,进行硫酸软骨素的碱提工艺优化研究。分别通过碱浓度、碱液温度、碱液量的单因素试验及该3个因素的正交试验,研究其对产品得率及其氨基己糖含量的影响,综合分析得出最佳的碱提工艺为2倍量6%的NaOH,于40℃的水浴中搅拌提取4h;该工艺条件制备鲟鱼硫酸软骨素的得率可高达40.45%,产品质量符合硫酸软骨素口服片(WS1-C3-0030-2000)标准的要求。鲟鱼硫酸软骨素精品和粗品对3种细胞乳腺癌细胞株(MCF-7细胞)、胃癌细胞株(MGc803细胞)、肝癌细胞株(SMMC7721)作用72h时,其IC50分别为7.28mg/mL、7.68mg/mL、4.25mg/mL和8.86mg/mL、9.27mg/mL、7.37mg/mL,与鲨鱼硫酸软骨素精品和粗品有着相似的抗肿瘤活性。  相似文献   
3.
筛选高效低毒的抗肿瘤药物是海洋新药研发最为重要的课题之一。软骨鱼软骨中富含多肽、低分子量蛋白、糖蛋白和多糖等活性物质,可以作为新生血管生成抑制因子、肿瘤细胞抑制因子、免疫调节因子和抗入侵因子等用于肿瘤的治疗和预防。本文对软骨鱼软骨中活性物质及其功效进行综述,将为软骨的研究利用提供参考。  相似文献   
4.
以冰浴鸡为试材,研究在寒冷刺激条件下对其膝关节软骨显微结构变化的影响。将20只健康蛋鸡随机分为对照组与试验组,对照组正常饲喂,试验组在正常饲喂的情况下每天对其膝关节进行2 h冰浴,持续30 d。取其膝关节软骨进行扫描电镜观察。结果表明:试验组关节软骨结构与对照组具有明显的差异。对照组软骨基质中胶原纤维排列呈拱形结构和薄壳结构,软骨细胞则顺胶原纤维方向排列于其间,结构致密;试验组软骨出现明显的退行性改变,软骨表面波浪状结构低平,拱形结构消失,软骨表面断裂,有胶原纤维及软骨细胞裸露,结构变得明显疏松。  相似文献   
5.
The objective of this study was to determine whether a prophylactic regimen of intramuscular polysulfated glycosaminoglycans (PSGAG), administered to growing Thoroughbred foals, would significantly reduce the incidence or severity of osteochondritis dissecans (OCD) or traumatic joint lesions that had been found in untreated foals (historical controls) from the same farm during the preceding 3 years. The number of PSGAG-treated foals with clinically significant joint lesions was 44.1% lower than the number of foals with OCD/joint injuries that had been found in the untreated historical controls. Surgical intervention of the treated foals declined 87.7% from the incidence on the farm during the preceding 3 years. Although the incidence of OCD lesions of the hock, stifle, and fetlocks in treated foals was not significantly different from that found in the matched controls, the lesions in the PSGAG-treated foals resolved without surgery. These results suggest that PSGAG has the potential to improve the clinical course of osteochondrosis (OC) and OCD. Additional studies are underway to determine whether a shorter or more targeted prophylactic regimen will provide a similar benefit.  相似文献   
6.
A bioassay for insulin-like growth factor (IGF), based on the in vitro incorporation of [35S]-sulfate into gill arch tissue was used to study the hormonal regulation of proteoglycan synthesis in the goldfish (Carassius auratus). [35S]-sulfate incorporation into gill arch tissue was found to be time-dependent with maximal uptake occurring by 48h, suggesting that proteoglycan synthesis in this tissue was maintained for at least 48h in vitro. The addition of human recombinant IGF-I (IGF-I) to the incubation medium was found to significantly stimulate [35S]-sulfate uptake into the gill arches, whereas bovine growth hormone (GH) was without effect. Porcine insulin was also stimulatory, but results indicate that the effects of porcine insulin and IGF-I may be mediated by a single receptor system. Finally, arches from hypophysectomized fish were significantly less responsive to IGF-I than were arches from sham-operated fish. Furthermore, administration of ovine GH in vivo appeared to increase subsequent responsiveness in vitro. Together, these results provide evidence that the growth-promoting actions of GH in the goldfish may be mediated, at least in part, by a peptide related in structure to mammalian IGF-I.  相似文献   
7.
Studies were undertaken to examine the importance of organic proteoglycan matrices in the calcification of elasmobranch vertebral cartilage. Proteoglycans were extracted from the vertebral cartilage of the clearnose skate, Raja eglanteria Bosc, with a 3M guanidine hydrochloride/10% EDTA solution. Proteoglycan solutions (12 g ml–1) were effective inhibitors of hydroxyapatite formation in vitro from high concentration calcium phosphate solutions. Inhibition of crystal formation appears to occur through the restriction of phase transformation from a calcium phosphate precursor to hydroxyapatite crystals. The concentration and/or degradation of proteoglycans in elasmobranch vertebral cartilage may have a physiological role in the production of alternating mineral-rich and mineral-poor growth zones, currently used in ageing studies.  相似文献   
8.
9.
The distal row of carpal bones (C2, C3, and C4) from eight left intercarpal joints--four from Standardbred Trotters and four from Swedish Warmblood horses--were used to assess the potential of magnetic resonance (MR) imaging to detect cartilage and bone lesions. The joints used in the study were classified by macroscopic and radiographic examinations as having normal, mild, moderate, or severe articular cartilage lesions and bone sclerosis. Those classifications correlated well with the appearance of the MR images. Bone sclerosis in the MR images was observed as regions of decreased signal intensity. Upon quantitative analysis of the MR images there was a significant difference (p < 0.0001) in the MR signal intensity from areas where radiographic bone sclerosis was observed compared to areas of radiographic nonsclerotic bone. In addition, the MR images were used to pilot the location of histology slices through areas of interest that were then examined microscopically; hence, the lesions found from the MR imaging examination were verified microscopically. It was concluded that cartilage lesions and cartilage loss are related to the sclerotic state of the underlying bone. The MR protocols developed in this study were applied on five intact cadaveric carpal joints, and it was concluded that MR imaging could successfully be used in the intact joint to detect minor cartilage and bone lesions not visualized by either radiography or macroscopic examination. Hence, MR imaging can be used to delineate interactions between articular cartilage and subchondral bone over time and in vivo.  相似文献   
10.
Degenerative joint disease (DJD) is common in domesticated cats. Our purpose was to describe how radiographic findings thought to indicate feline DJD relate to macroscopic cartilage degeneration in appendicular joints. Thirty adult cats euthanized for reasons unrelated to this study were evaluated. Orthogonal digital radiographs of the elbow, tarsus, stifle, and coxofemoral joints were evaluated for the presence of DJD. The same joints were dissected for visual inspection of changes indicative of DJD and macroscopic cartilage damage was graded using a Total Cartilage Damage Score. When considering all joints, there was statistically significant fair correlation between cartilage damage and the presence of osteophytes and joint‐associated mineralizations, and the subjective radiographic DJD score. Most correlations were statistically significant when looking at the different joints individually, but only the correlation between the presence of osteophytes and the subjective radiographic DJD score with the presence of cartilage damage in the elbow and coxofemoral joints had a value above 0.4 (moderate correlation). The joints most likely to have cartilage damage without radiographic evidence of DJD are the stifle (71% of radiographically normal joints) followed by the coxofemoral joint (57%), elbow (57%), and tarsal joint (46%). Our data support radiographic findings not relating well to cartilage degeneration, and that other modalities should be evaluated to aid in making a diagnosis of feline DJD.  相似文献   
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