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991.
Hussain R Daud S Kakar N Ahmad A Baloch AH Tareen AM Kakar MA Ahmad J 《Molecular biology reports》2012,39(5):6197-6201
Canavan disease (OMIM 271900) is an autosomal recessive lethal neurodegenerative disorder characterized by spongy degeneration
of the brain. A highly consanguineous Pakistani family with Canavan disease was enrolled on the basis of diagnosis. All the
affected individuals have mental retardation, megalocephaly and degradation of motor skills, poor head control, partial vision
loss, weakness of the muscles and raised urinary concentration of N-acetyl aspartic acid in the urine. Blood samples were
collected from affected as well as normal siblings and processed for DNA purification. Linkage analysis was performed by typing
three short tandem repeat markers D17S1583 (7.19 cM), D17S1828 (10.02 cM) and D17S919 (14.69 cM) for an already-reported gene/locus
ASPA at chromosome 17p13.2 causing Canavan disease. During linkage analysis, all the affected individuals were homozygous for
short tandem repeat markers while the normal siblings were heterozygous showing co-segregation of the disease. Gene ASPA (NM_000049) was undertaken to sequence for mutation analysis. As a result of sequence analysis, we found missense substitution
740A→G (p.G274R) in exon 6 of gene ASPA. To our knowledge, this is the first report about Canavan disease on a Pakistani family. 相似文献
992.
Azam A Babar ME Firyal S Anjum AA Akhtar N Asif M Hussain T 《Molecular biology reports》2012,39(2):845-849
Microsatellite markers are used for any individual identity and breed characterization in animals that is an efficient and
successful way of investigation. They are used for multiple purposes as genetic detectors including, rapid mutation rate,
high level of polymorphism, and range of variety of microsatellite markers available. A panel of 19 microsatellite markers
was developed for breed characterization in Tharparkar and Red Sindhi breeds of cattle in Pakistan. Forty four blood samples
of cattle (each breed) were collected from Department of Livestock Management, Sindh Agriculture University, Tandojam, Tando
Qaiser, Tharparkar Cattle Farm Nabi sar Road, Umer Kot, Sindh, and Govt. Red Sindhi Cattle Breeding Farm, Tando Muhammad Khan
Pakistan. Breed characterization was 100% successful. Average PIC, He and Power of Exclusion values were found to be 0.91,
0.62 and 13.28, respectively. Pattern of allelic frequencies of most of the microsatellite markers were clearly distinct between
two breeds. As a result of present study a reliable, efficient and very informative panel of microsatellite markers was successfully
developed which was capable to interpret individual identity, forensic cases and breed characterization in cattle. This facility
is ready to be provided to local cattle breeder at commercial level for DNA testing of cattle. This study will also be highly
helpful for breed conservation of cattle. In addition this study can also become a basis to open up new disciplines of animal
forensics in Pakistan. 相似文献
993.
Owing to their physical and chemical properties, inorganic functional materials have tremendous impacts on key technologies such as energy generation and storage, information, medicine, and automotive engineering. Nature, on the other hand, provides evolution-optimized processes, which lead to multifunctional inorganic-bio-organic materials with complex structures. Their formation occurs under physiological conditions, and is goverened by a combination of highly regulated biological processes and intrinsic chemical properties. Nevertheless, insights into the molecular mechanisms of biomineralization open up promising perspectives for bioinspired and biomimetic design and the development of inorganic-bio-organic multifunctional hybrids. Therefore, biomimetic approaches may disclose new synthetic routes under ambient conditions by integrating the concept of gene-regulated biomineralization principles. The skeletal structures of marine sponges provide an interesting example of biosilicification via enzymatically controlled and gene-regulated silica metabolism. Spicule formation is initiated intracellularly by a fine-tuned genetic mechanism, which involves silica deposition in vesicles (silicassomes) under the control of the enzyme silicatein, which has both catalytic and templating functions. In this review, we place an emphasis on the fabrication of biologically inspired materials with silicatein as a biocatalyst. 相似文献
994.
Muhammad A Anis I Ali Z Awadelkarim S Khan A Khalid A Shah MR Galal M Khan IA Iqbal Choudhary M 《Bioorganic & medicinal chemistry letters》2012,22(1):610-612
A new methylene-bridged bisflavonoid, methylenebissantin (1), and nine known compounds, including flavonoids (2-5), diterpenoids (6 and 7), and phenol derivatives (8-10) were isolated from the aerial parts of Dodonaea viscosa Jacq. The structure elucidation was based on spectroscopic data analyses. The isolated compounds were evaluated for the inhibition of Plasmodium falciparum enoyl-ACP reductase (PfENR). Methylenebissantin (1) exhibited a moderate inhibition (IC(50) 91.13 μM) against PfENR. 相似文献
995.
996.
Mustafa G Khan IU Ashraf M Afzal I Shahzad SA Shafiq M 《Bioorganic & medicinal chemistry》2012,20(8):2535-2539
The present study describes a convenient method for the synthesis of new lipoxygenase inhibitors, 4-(toluene-4-sulfonylamino)-benzoic acids from p-amino benzoic acid. Reaction of p-amino benzoic acid with p-toluenesulfonyl chloride provided thirteen N- and O-alkylation products 4a-4m in moderate to good yields. Lipoxygenase inhibition of newly formed sulfonamide derivatives was investigated and some of these compounds 4m, 4g, 4e, 4f and 4j showed good lipoxygenase inhibitory activities with IC(50) values ranged between 15.8 ± 0.57 and 91.7 ± 0.61 μmol whilst all other compounds exhibited mild anti-lipoxygenase activities with IC(50) values ranged between 139.2 ± 0.75 and 232.1 ± 0.78 μmol. N-alkylated products were more active against the enzyme than O-alkylated or both N- and O-alkylated ones. All synthesized sulfonamides were recrystallized in chloroform to give these title compounds which were characterized using FTIR, (1)H NMR, (13)C NMR, elemental analysis and single crystal X-ray diffraction techniques. 相似文献
997.
蚜小蜂Bemisia tabaci是烟粉虱的重要天敌, 其中双斑恩蚜小蜂Encarsia bimaculata, 丽蚜小蜂E. formosa以及浅黄恩蚜小蜂E. sophia是国内烟粉虱寄生蜂3个优势种。本研究以采自中国华南、 华东、 华北、 西南地区以及马来西亚、 埃及的E. bimaculata、 E. formosa和E. sophia 3个优势种的8个不同地理种群为研究对象, 对其28S rRNA D2和D3扩展区序列进行了测定和分析。结果表明: Encarsia属的恩蚜小蜂其28S rRNA D2和D3序列在种间水平上高度保守; 与丽蚜小蜂相比, 双斑蚜小蜂与浅黄恩蚜小蜂在遗传关系上更为接近。依据28S rRNA和D2序列的系统发育分析结果显示, 同一种的蚜小蜂其种内也存在一定的遗传分化, 比如中国广东的浅黄恩蚜小蜂种群与澳大利亚、 西班牙、 埃及和埃塞俄比亚的浅黄恩蚜小蜂种群接近, 而与泰国的种群的亲缘关系则较远。在系统发育树上, 来自不同国家的(苏丹、 埃及和危地马拉以及澳大利亚)的双斑蚜小蜂种群聚集在同一分支上; 同时, 来自中国衡水和昆明的丽蚜小蜂种群也与来自美国的丽蚜小蜂种群聚集在一起, 却与埃及的种群相距较远。对造成这种同种寄生蜂不同种群之间在遗传距离和地理距离不对称的原因进行了探讨。 相似文献
998.
999.
MOTIVATION: Rhodopsin is a visual pigment present in rod cells of retina. It belongs to GPCR family and involves photoisomerization of 11-cis-retinal to all-trans-retinal isomers, conformational changes in rhodopsin and signal transduction cascade to generate a nerve impulse. This signaling pathway has been targeted to eliminate the effect of a mutation (Gly90→Asp) responsible for abnormal activation of G-protein without retinal conformations in the absence of light leading to congenital night blindness. A theoretical model of rhodopsin with induced mutation has been deliberated in order to find potential ligands which can offset this mutational effect. The binding interactions between the target mutated rhodopsin model and potential ligands have been predicted with the help of molecular docking. The results indicated strong functional benefits of ligands as an inhibitor and an agonist for mutated rhodopsin model. Therefore, we propose a new visual cascade model which can initiate the normal signaling of rhodopsin mutant with the help of proposed ligands and can provide a hope for vision in future. 相似文献
1000.
Saqib H. Ansari Tahir S. Shamsi Mushtaq Ashraf Tasneem Farzana Muneera Bohray Kousar Perveen Sajida Erum Iqra Ansari Muhammad Nadeem Ahmed Masood Ahmed Faizan Raza 《Indian journal of human genetics》2012,18(2):193-197