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991.
992.
AIM: To analyze the nucleotide and putative amino acid sequences of PIA genes isolated from N.gonorrhoeae and to construct the prokaryotic expression system of PIA gene.METHODS: The entire PIA genes from 9 strains of N.gonorrhoeae were amplified by using high fidelity PCR.The target amplification fragments were sequenced after T-A cloning.Homology comparison of the nucleotide and putative amino acid sequences of PIA genes from the isolates with the reported sequences in GenBank was then performed.A prokaryotic expression system of PIA gene was constructed.Different dosages of IPTG were applied to induce the expression of the target recombinant protein (rPIA) and 10% SDS-PAGE plus Bio-Rad Agarose Image Analysor was used to determine the expression level of rPIA.rPIA was extracted using Ni-NTA affinity chromatography and the purified effect was detected by SDS-PAGE.RESULTS: In comparison with the reported PIA gene sequences (GenBank No: L19962),the homologies of nucleotide and putative amino acid sequences of PIA genes from the isolates were 99.6%-100% and 99.1%-100%,respectively,which indicated that all the isolates were belonging to serovars IA6.Output of rPIA was as high as 50.1% of the total bacterial proteins.The purified rPIA only showed a single target protein fragment in gel.CONCLUSION: Serovar IA6 is dominant in the local N.gonorrhoeae isolates and sequences of the encoding gene are relatively conserved.The constructed prokaryotic expression system is able to express rPIA with high efficiency,which may lay a foundation for further development of serological detection kit and vaccine of N.gonorrhoeae.  相似文献   
993.
不同装液量对金顶侧耳液体摇瓶培养的影响   总被引:1,自引:0,他引:1  
以食用菌金顶侧耳为试验研究对象;用综合PDA(马铃薯20 g,葡萄糖20 g,硫酸镁1.5g,磷酸二氢钾3.0g,水1 000 mL,pH自然)为液体培养基;以(25±1)℃,180 r/min为气浴恒温振荡器的温度和振荡速率.设定了60、80、100、120、140 mL 5个不同的装液量.经过7 d的摇瓶培养,过滤发酵液,得到菌丝体和粗酶液.再通过测定菌丝体烘干后的生物量,以及测定粗酶液中多酚氧化酶和漆酶活性,得出了:装液量为100 mL,菌丝体烘干生物量明显大于其他装液量;装液量为140 mL,有利于多酚氧化酶的分泌,酶的活力较强,并且其活力随装液量的递增而变强.装液量为100mL,有利于漆酶的分泌,酶的活力较强,不同装液量的菌丝生长都在第6天出现了高峰期,其中以装液量为100mL/250mL时,其菌丝球数量较多.  相似文献   
994.
氮肥运筹对杂交苏丹草产量饲用品质及再生系数的影响   总被引:9,自引:10,他引:9  
采用大田小区栽培试验,研究了氮肥对杂交苏丹草产量和饲用营养品质及再生系数的影响。结果表明,杂交苏丹草干物质总产量氮肥处理显著高于对照,N4处理最高,相同的施氮量分次施用比一次性施用增产效果好。氮肥处理粗蛋白(CP)含量均高于对照,头茬草CP含量最高,随收获次数增加,CP含量降低,分次施肥处理施氮量增加,CP含量降低。对照处理粗灰分(CA)含量最高,随收获次数增加CA和酸性洗涤纤维(ADF)含量降低,无氮浸出物(NFE)含量升高。杂交苏丹草5大营养成分产量均是N4处理最高,对照最低,CP产量顺序是N4>N1>N2>N3>N0,3次收获的粗脂肪(EE)、CA、ADF、NFE总产量,均是肥料分次施用比一次性施用的处理高。各氮肥处理总能量(GE)均高于对照,其中N4处理最高,其次是N2处理,分次施肥的处理有利于总能量的增加。再生系数表现为相同施氮量分次施用处理高于一次性施用的处理,N4处理可使杂交苏丹草再生系数达到最大。比较发现,生产上采用N4(600 kg/hm2,底肥∶追肥=1∶2)处理可获得高产优质的牧草。  相似文献   
995.
AIM:To study the relationship between serum insulin-like growth factor- 1 (IGF-1), insulin-like growth factor binding protein-3 (IGFBP-3) levels, bone mineral density(BMD) and bone metabolic markers in postmenopausal women. METHODS:Serum IGF-1, IGFBP-3, osteocalcin(BGP), isomeric C-telopeptide of type I collagen (β-CTX), estradiol(E2), calcitonin(CT), parathormone(PTH), calcium (Ca), and phosphorus(P) were measured in 90 postmenopausal osteoporosis patients and 70 healthy postmenopausal women. BMD of lumbar vertebra and left femoral neck were determined by dual energy X-ray absorptiometry.RESULTS:BMD of lumbar vertebra and left femoral neck decreased significantly (P<0.01), serum IGF-1, IGFBP-3, E2, CT and BGP decreased significantly (P<0.01), serum β-CTX and PTH increased significantly in postmenopausal osteoporosis group (P<0.01). There were no significantly differences in serum Ca, P between two groups (P>0.05). BMD of lumbar vertebra and left femoral neck were positively correlated with serum IGF-1, IGFBP-3, E2, CT and BGP, but negatively correlated with β CTX and PTH. There were no correlation with serum Ca, P and BMD.CONCLUSION:Serum IGF-1, IGFBP-3, E2, CT, BGP, β-CTX and PTH level were correlated with BMD of lumbar vertebra and left femoral neck. These markers can be one of the valuable evidences for screening osteoporosis in postmenopausal women.  相似文献   
996.
997.
AIM: To study the effect of late reperfusion on apoptotic cardiomyocytes in the risk area of acute myocardial infarctin in dogs. METHODS: The experiment was divided into three groups: sham operation group, acute myocardial infarction (AMI) group, and late reperfusion (LR) group. Apart from sham operation group, the other two groups were subjected to left anterior descending branch of coronary artery ligation. The acute myocardial infarction group was only subjected to ligation for 12 hours, late reperfusion group was subjected to ligation for 6 hours following by 6 hours of reperfusion. The cardiomyocyte apoptosis was measured by TUNEL assay. Immunohistochemistry and Western blotting analysis were used to detect the expression of Bcl-2 and Bax protein. RESULTS: The number of apoptotic cardiomyocytes in late reperfusion group was much less than acute myocardial infarction group (P<0.05), and increased significantily as compared with sham operation group (P<0.01). The expression of Bcl-2 protein was enhanced gently in late reperfusion group in contrast to acute myocardial infarction group, but no significant difference in the two groups (P>0.05) was observed, although it was much more in the two groups than that in sham operation group (P<0.01). The expression of Bax protein in late reperfusion group was much higher than that in sham operation group (P<0.01), and was lower than that in acute myocardial infarction group (P<0.05). CONCLUSION: Late reperfusion reduces cardiomyocyte apoptosis in the risk area of acute myocardial infarction. The mechanism may be that late reperfusion can decrease the expression of Bax protein.  相似文献   
998.
AIM:To investigate the changes of efferent system functions in noise-induced hearing loss (NIHL) patients and find out a method of clinic diagnosis for NIHL.METHODS:The amplitudes of distortion product otoacoustic emission were measured with and without contralateral broad-band noise using Celesta-503 otoacoustic emission analyzer. The efferent system functions were evaluated by the amplitudes of contralateral suppression.RESULTS:The contralateral suppressions in NIHL patients were significant lower than those in control group in low frequency (0.75 kHz and 1 kHz) of DP-gram and low level primary tone in 2 kHz input/output function. There were no significant differences in contralateral suppressions of 4 kHz and 6 kHz input/output function between NIHL patients and control group.CONCLUSION:The contralateral suppressions in NIHL patients are lower than those in normal hearing subjects and the measurements of efferent system functions could be used in early detection and clinic diagnosis for NIHL.  相似文献   
999.
在新疆干旱区,由于暖季沙漠增温效应的影响,与沙漠相邻绿洲区的热量资源相对优越,为植棉提供了有利条件。但随着时空变化,绿洲棉花热量生产潜力也呈现出相应的分异规律。本文以新疆北疆玛河流域石河子平原绿洲区为例,将绿洲与沙漠联系起来考虑,分析了距沙漠不同距离梯度的绿洲区棉花热量生产潜力。结果表明:石河子平原绿洲区内,距离沙漠最近区与最远区之间棉花热量生产潜力相差389Kg/hm2,绿洲与沙漠的距离平均每增加10Km,热量生产潜力下降43Kg/hm2。暖季沙漠增温效应对绿洲棉花的热量生产潜力影响明显,沙漠对相邻绿洲区的农业生产有着正面影响,起到了除太阳外第二个热量源的作用。  相似文献   
1000.
新疆旅游经济非均衡演变的时空特征分析   总被引:5,自引:0,他引:5  
本文以区域经济学为基础,运用标准差和变异系数等方法,分析了新疆15个地州近10年旅游经济的区域非均衡发展的总体水平及时空特征,揭示了新疆旅游经济水平在国民经济中产业地位的分异规律,探讨了旅游区域差异的动因,提出了缩小地区差异、协调新疆旅游业发展的对策。  相似文献   
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