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171.
试验旨在探讨稳定可靠的贮精腺上皮细胞分离及原代培养方法,为研究鸡贮精机理提供细胞模型。以鸡输卵管的子宫阴道交接部组织样为材料,采用酶消化法和组织块培养法分离培养母鸡贮精腺上皮细胞,观察母鸡贮精腺上皮细胞的培养情况,比较不同细胞培养方法获得贮精腺上皮细胞的生长情况。结果表明,用胶原酶或胰酶单独消化母鸡子宫阴道交接部组织,经100目过滤后获得的贮精腺上皮细胞24 h后可贴壁,但48~72 h后细胞死亡;用胶原酶Ⅺ(0.01 g/mL)与胰酶(0.25%)先后消化母鸡子宫阴道交接部组织后再经100目过滤获得的贮精腺上皮细胞贴壁性良好,24~48 h细胞出现明显增殖,72 h后细胞增殖速度减慢,开始死亡;用组织块培养法7 d可获得鸡贮精腺上皮原代细胞,该细胞可传2~3代;用组织块培养法获得的细胞进行免疫组化试验,发现细胞表达贮精腺差异表达基因编码的NXPH1蛋白,该蛋白在培养细胞内的表达符合其分泌蛋白特性,表明组织块培养法所获细胞可用于后续研究。综上,用组织块培养法获得的鸡贮精腺上皮细胞可为研究母鸡贮精腺机制提供细胞模型。  相似文献   
172.
为了阐明树鼩精子中是否存在丝氨酸/苏氨酸蛋白磷酸酶1γ2(PP1γ2)及其在附睾精子中的存在形式,进而探究PP1γ2对精子成熟和运动性的调控作用,本试验以树鼩为研究对象,采用Western blotting分析了不同条件下树鼩附睾头和附睾尾精子中PP1γ2的存在形式和磷酸化程度,探讨了双丁酰环腺苷酸(db-cAMP)、3-异丁基-1-甲基黄嘌呤(IBMX)或Ca2+对树鼩精子中PP1γ2磷酸化表达水平的影响,并进一步研究了磷酸酶抑制剂冈田酸(okadaic acid,OA)和花萼海绵诱癌素A(calyculin A,CA)对树鼩精子中PP1γ2磷酸化程度的影响及其对树鼩附睾头和附睾尾精子运动度的影响。结果显示,在树鼩附睾头和附睾尾精子中均存在PP1γ2,且在等量的附睾头和附睾尾精子蛋白中,PP1γ2在附睾尾精子的磷酸化程度远高于附睾头精子;db-cAMP、IBMX或Ca2+不改变PP1γ2的磷酸化水平;磷酸酶抑制剂OA和CA能明显提高附睾头和附睾尾中PP1γ2磷酸化的程度,且能显著提高精子(尤其是附睾头精子)的运动度(P<0.05),OA和CA的最佳作用浓度分别为1μmol/L和10 nmol/L,最佳作用时间分别为15、20 min。本研究结果表明,蛋白磷酸酶PP1γ2对树鼩精子成熟及运动性具有重要的调控作用,其主要通过磷酸化和去磷酸化的变化发挥作用。  相似文献   
173.
笔者拟探讨疏肝益阳胶囊(SGYY)对炔雌醚(QES)诱导大鼠生精紊乱和氧化应激的缓解作用及机制。将20只8周龄雄性SD大鼠随机分为4组,适应饲养1周后,进行药物灌胃处理,对照组:0.1mL生理盐水+0.1mL橄榄油;SGYY组:100 mg·kg-1 SGYY;QES组:0.1 mg·kg-1 QES;QES+SGYY组:0.1 mg·kg-1 QES+100mg·kg-1 SGYY。QES溶于橄榄油;SGYY溶于生理盐水;每天1次,连续2周。处理结束后,取睾丸、附睾、精囊腺和前列腺称重、测量长径与短径,并制备睾丸组织切片,通过HE染色,观察睾丸生精小管组织结构、生精细胞比例的变化;通过免疫组织化学方法检测睾丸生精细胞PCNA表达,Tunel法检测细胞凋亡;分离血浆,检测睾酮含量变化。取睾丸匀浆检测抗氧化酶活性。结果显示,QES处理后大鼠生殖器官的质量显著下降,附睾的精子数量显著减少;生精小管的面积、直径、生精上皮的高度和生精细胞数量均显著减少。而且,生精细胞的PCNA表达和血浆睾酮含量明显下降,Tunel阳性细胞数明显增加。睾丸SOD、GSH-Px和T-AOC活性显著下降,MDA含量显著升高。SGYY增加生殖器官质量、精子数量、睾丸睾酮含量、增殖的生精细胞数量和抗氧化酶活性,降低了MDA含量和Tunel的表达。结果表明,SGYY通过改善抗氧化功能、抑制氧化应激及促进睾酮分泌等途径增加了生精细胞数量并提高睾丸的生精功能。  相似文献   
174.
This study was conducted to evaluate the effect of nicotinic acid on plasma membrane integrity and fatty acid composition in frozen–thawed boar sperm. Boar semen was cryopreserved using freezing extender containing nicotinic acid (NA), then plasma membrane integrity, osmotic equilibration, lipid peroxidation and fatty acid were analysed. The plasma membrane integrity of frozen–thawed sperm was significantly higher in the 10 mM NA than in the 0 and 20 mM NA treatment groups (p < 0.05). Additionally, the osmotic equilibration ability was not different in treatment groups, but lipid peroxidation was significantly decreased in the 10 mM NA treatment group (p < 0.05). The saturated fatty acids were significantly decreased in the 10 mM NA treatment group, and C18:1n‐9, C18:2n‐6, C20:4n‐6, C22:5n‐6 and C22:6n‐3, and total polyunsaturated fatty acids (PUFAs) were significantly increased in the 10 mM NA treatment groups (p < 0.05). In summary, 10 mM NA improved plasma membrane integrity, inhibited lipid peroxidation and increased PUFAs in frozen–thawed boar sperm. These results suggest that NA may be useful to protect the plasma membrane and inhibit the loss of PUFAs for sperm cryopreservation in pigs.  相似文献   
175.
Sperm from fertile donkeys have been successfully frozen in absence of permeable cryoprotectants. The aim of this study was to determine whether this cryopreservation method is suitable for subfertile donkeys in comparison to conventional sperm freezing with glycerol. Ejaculates were collected from four Andalusian Donkeys: three fertile and one subfertile. Semen was frozen with an extender containing glycerol (GLY), or adding instead sucrose 0.25 molar and 1% bovine serum albumin (SUC) as non‐permeable cryoprotectants. After thawing, samples were assessed for total (TM, %) and progressive (PM, %) sperm motility by CASA, plasma membrane integrity (PMI, %) by epifluorescence microscopy and DNA integrity (DFI, %) by SCSA. Results (mean ± SD) were compared between extenders in fertile and subfertile donkeys using the Student's t test. No differences between GLY and SUC treatments were found in the fertile group for the sperm parameters assessed. In subfertile donkey ejaculates, GLY resulted in significantly higher values than SUC for TM (25.5 ± 3.1 vs. 19.6 ± 1.9) and PM (13.3 ± 5.1 vs. 4.0 ± 1.2), respectively. In conclusion, considering all the sperm parameters assessed, sperm freezing in absence of permeable cryoprotectants may not be still an option for cryopreservation of subfertile donkey sperm.  相似文献   
176.
We aimed to elucidate whether NO acts in in vitro sperm capacitation in bovine via cGMP/PKG1 pathway. For this, cryopreserved bovine sperm were capacitated in vitro with 20 µg/ml heparin (Control) plus treatments: 1 mM L‐arginine (L‐arg, NO precursor), 50 µM Rp‐8‐Bromo‐β‐phenyl‐1,N2‐ethenoguanosine‐3′,5′‐cyclic monophosphorothioate (Rp‐8‐Br‐cGMPS, selective inhibitor of the binding site for cGMP in PKG1), 1 mM 2‐Phenyl‐4,4,5,5‐tetramethylimidazoline‐1‐oxyl 3‐oxide (PTIO, NO scavenger), and the combinations of L‐arg + RP‐8‐Br‐cGMPS and L‐arg + PTIO. Sperm motility and vigour were determined by phase‐contrast microscopy, capacitation status by chlortetracycline staining, and the intracellular concentration of cGMP was measured by ELISA. Data were subjected to analysis of variance and means compared with SNK test at 5% probability. Motility and vigour were lower in sperm treated with PTIO when compared to Control and other treatments (p < .05). The L‐arg treatment showed the highest percentage of capacitated sperm when compared to the Control and other treatments (Rp‐8‐Br‐cGMPS, L‐arg + Rp‐8‐Br‐cGMPS and PTIO) (69.8 ± 3.4%, 51.2 ± 3.0, 51.1 ± 2.1, 51.2 ± 3.0 and 45.5 ± 2.7, respectively) (p < .05). The capacitation ratio (%) was lower in treatments with Rp‐8‐Br‐cGMPS, L‐arg + Rp‐8‐Br‐cGMPS and PTIO, respectively (p < .05). Lastly, cGMP concentration (pmol/ml) was lower in PTIO and L‐arg + PTIO (1.3 ± 0.3 and 1.6 ± 0.4) and was higher in Rp‐8‐Br‐cGMPS and L‐arg + Rp‐8‐Br‐cGMPS (3.7 ± 0.4 and 4.0 ± 0.5) treatments. We showed that during in vitro capacitation of cattle: (a) NO influences sperm motility and vigour; (b) NO is associated with cGMP synthesis through two independent pathways and (c) the cGMP/PKG1 pathway has a partial role in sperm capacitation and does not involve the L‐arg/NO.  相似文献   
177.
Sperm competition is a powerful selective force that has influenced many reproductive traits in males and females although additional evolutionary explanations may help to understand the diversity of mammalian reproduction. Sperm morphology varies considerably in mammals with extreme examples in several rodent lineages in which a wide range of sizes and complex head morphologies have been identified. Mammalian spermatozoa also differ in function, with swimming velocity and trajectory showing much divergence. Underlying processes mediating function have received little attention so far, but differences in timing and proportion of sperm undergoing capacitation or acrosomal exocytosis may be related to variation in signalling processes. Furthermore, energy required for sperm functions (such as motion, signalling and overall maintenance of cell integrity) can be produced and consumed, following different patterns among species and this could be the result of several selective forces. A more thorough understanding of the diversity in structure and function of sperm cells, and underlying selective forces, may help us develop better methods to assess them taking into account particulars and generalities of sperm form and performance. Such tests could then become more reliable in estimations of the impact of cryopreservation or effect of changes in the environment and their relevance for fertility.  相似文献   
178.
家畜性别控制技术的研究进展   总被引:3,自引:0,他引:3  
在畜牧生产中,人为控制出生家畜的性别可以降低生产成本,提高经济效益。随着科技的进步和研究的不断深入,家畜性别控制技术也在不断的完善。作者综述了X、Y精子的分离和胚胎性别鉴定这两项家畜性控技术的发展历程和研究现状,并对其今后的研究方向及应用前景进行了展望。  相似文献   
179.
There are clear differences in the normal radiographic appearance of the abdominal organs between a left lateral vs. a right lateral view. While a few veterinary academic institutions have transitioned to a three‐view abdominal radiographic study protocol, obtaining only two views of the canine abdomen remains the current standard in veterinary medicine. In this combined retrospective and prospective, case‐controlled study, 48 canine patients presenting with signs of acute abdomen were recruited. Four board‐certified veterinary radiologists and four general practice veterinarians with greater than 3 years of experience in small animal practice were asked to determine if 10 predetermined findings were present within the set of images and if surgery was recommended based on those findings. Image readers were unaware of the clinical history. Three‐view studies did not yield statistically significantly greater accuracy than two‐view studies when evaluating all readers together. No statistically significant associations between the availability of the third view and increased accuracy or confidence were found in evaluations of general practitioners specifically. Evaluation of three‐view radiographic examination, as compared to two‐view examination, did not have perceived or statistically significantly increased diagnostic utility. Based on our findings, there is no statistically increased utility to justify a standard three‐view abdominal radiographic examination over a two‐view study for canines presenting with signs of acute abdomen.  相似文献   
180.
The main aim of the present study was to evaluate the cryoprotective effect of apigenin (AP) and ferulic acid (FA) on boar sperm during cryopreservation. AP and FA were both demonstrated to be high‐efficiency antioxidants and had not previously been used to protect sperm from cryodamage. As boar sperm is sensitive to oxidative stress, suitable antioxidants are still needed for improving frozen‐thawed sperm quality. With this purpose, semen samples coming from five boars were used in this study. Ejaculates of five boars were mixed and split into 16 aliquots, in which different doses of AP and FA were added separately or together. The motility, the plasma membrane integrity, the mitochondrial activity, the acrosomal integrity, the antioxidase activities and the malondialdehyde concentration of the frozen‐thawed boar sperm were assessed. The results suggested that both AP and FA significantly improved the frozen‐thawed boar sperm quality in all these aspects when they were added to the freezing extender separately, while the highest improvement was recorded when the extender was supplemented with 0.1 mmol/L AP plus 0.15 mmol/L FA. These findings demonstrated that supplementation of freezing extender with both AP and FA had a combined, beneficial effect on frozen‐thawed boar sperm.  相似文献   
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