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981.
Ibrahim H. Eissa Radwan El-Haggar Mohammed A. Dahab Marwa F. Ahmed Hazem A. Mahdy Reem I. Alsantali Alaa Elwan Nicolas Masurier Samar S. Fatahala 《Journal of enzyme inhibition and medicinal chemistry》2022,37(1):1587
A novel series of 2-thioacetamide linked benzoxazole-benzamide conjugates 1–15 was designed as potential inhibitors of the vascular endothelial growth factor receptor-2 (VEGFR-2). The prepared compounds were evaluated for their potential antitumor activity and their corresponding selective cytotoxicity was estimated using normal human fibroblast (WI-38) cells. Compounds 1, 9–12 and 15 showed good selectivity and displayed excellent cytotoxic activity against both HCT-116 and MCF-7 cancer cell lines compared to sorafenib, used as a reference compound. Furthermore, compounds 1 and 11 showed potent VEGFR-2 inhibitory activity. The cell cycle progression assay showed that 1 and 11 induced cell cycle arrest at G2/M phase, with a concomitant increase in the pre-G1 cell population. Further pharmacological studies showed that 1 and 11 induced apoptosis and inhibited the expression of the anti-apoptotic Bcl-2 and Bcl-xL proteins in both cell lines. Therefore, compounds 1 and 11 might serve as promising candidates for future anticancer therapy development. 相似文献
982.
Satarupa Bhaduri Analine Aguayo Yusuke Ohno Marco Proietto Jasmine Jung Isabel Wang Rachel Kandel Narinderbir Singh Ikran Ibrahim Amit Fulzele Eric J Bennett Akio Kihara Sonya E Neal 《The EMBO journal》2023,42(4)
Nearly one‐third of nascent proteins are initially targeted to the endoplasmic reticulum (ER), where they are correctly folded and assembled before being delivered to their final cellular destinations. To prevent the accumulation of misfolded membrane proteins, ER‐associated degradation (ERAD) removes these client proteins from the ER membrane to the cytosol in a process known as retrotranslocation. Our previous work demonstrated that rhomboid pseudoprotease Dfm1 is involved in the retrotranslocation of ubiquitinated membrane integral ERAD substrates. Herein, we found that Dfm1 associates with the SPOTS complex, which is composed of serine palmitoyltransferase (SPT) enzymes and accessory components that are critical for catalyzing the first rate‐limiting step of the sphingolipid biosynthesis pathway. Furthermore, Dfm1 employs an ERAD‐independent role for facilitating the ER export and endosome‐ and Golgi‐associated degradation (EGAD) of Orm2, which is a major antagonist of SPT activity. Given that the accumulation of human Orm2 homologs, ORMDLs, is associated with various pathologies, our study serves as a molecular foothold for understanding how dysregulation of sphingolipid metabolism leads to various diseases. 相似文献
983.
984.
Storage of sequence data is a big concern as the amount of data generated is exponential in nature at several locations. Therefore,
there is a need to develop techniques to store data using compression algorithm. Here we describe optimal storage algorithm
(OPTSDNA) for storing large amount of DNA sequences of varying length. This paper provides performance analysis of optimal
storage algorithm (OPTSDNA) of a distributed bioinformatics computing system for analysis of DNA sequences. OPTSDNA
algorithm is used for storing various sizes of DNA sequences into database. DNA sequences of different lengths were stored by
using this algorithm. These input DNA sequences are varied in size from very small to very large. Storage size is calculated by this
algorithm. Response time is also calculated in this work. The efficiency and performance of the algorithm is high (in size calculation
with percentage) when compared with other known with sequential approach. 相似文献
985.
Mohamed El Sekily Sohila Mancy Ibrahim El Kholy El Sayed H. El Ashry Hassan S. El Khadem David L. Swartz 《Carbohydrate research》1977,59(1):141-149
L-threo-2,3-Hexodiulosono-1,4-lactone 2-phenylhydrazone(1) reacted with hydroxylamine to give the 3-oxime 2-phenylhydrazone(2). On boiling with acetic anhydride,2 was dehydrated to 4-[L-threo-2,3-diacetoxy-(1-hydroxypropyl)]-2-phenyl-1,2,3-triazole-5-car?ylic acid lactone(3), which was converted into 2-phenyl-4-(L-threo-1,2,3-trihydroxypropyl)-1,2,3-triazole-5-car?amide(4) with liquid ammonia. The structure of compound4 was confirmed by acetylation to 2-phenyl-4-(L-threo-1,2,3-triacetoxypropyl)-1,2,3-triazole-5-car?amide(5), and by periodate oxidation followed by reduction, to give 4-(hydroxymethyl)-2-phenyl-1,2,3-triazole-5-car?amide(6). Treatment of compound1 with aryl- or aroyl-hydrazines afforded mixed bishydrazones(7–14), which were acetylated to15–21, and treated with hydrazine to give pyrazolinediones22 and23 相似文献
986.
Nuha Elhassan Eyoab Iyasu Gebremeskel Mohamed Ali Elnour Dan Isabirye John Okello Ayman Hussien Dominic Kwiatksowski Jibril Hirbo Sara Tishkoff Muntaser E. Ibrahim 《PloS one》2014,9(5)
Human genetic variation particularly in Africa is still poorly understood. This is despite a consensus on the large African effective population size compared to populations from other continents. Based on sequencing of the mitochondrial Cytochrome C Oxidase subunit II (MT-CO2), and genome wide microsatellite data we observe evidence suggesting the effective size (Ne) of humans to be larger than the current estimates, with a foci of increased genetic diversity in east Africa, and a population size of east Africans being at least 2-6 fold larger than other populations. Both phylogenetic and network analysis indicate that east Africans possess more ancestral lineages in comparison to various continental populations placing them at the root of the human evolutionary tree. Our results also affirm east Africa as the likely spot from which migration towards Asia has taken place. The study reflects the spectacular level of sequence variation within east Africans in comparison to the global sample, and appeals for further studies that may contribute towards filling the existing gaps in the database. The implication of these data to current genomic research, as well as the need to carry out defined studies of human genetic variation that includes more African populations; particularly east Africans is paramount. 相似文献
987.
An Investigation of Wound Healing in Sugar Beet Roots Using Light and Fluorescence Microscopy 总被引:1,自引:1,他引:0
Following impact, wound healing was investigated in roots ofsugar beet using fluorescence microscopy in conjunction witha conventional lignin test. Samples of sugar beet roots wereharvested at different stages of development and impacted inthe laboratory with a falling bolt delivering 14 Joules.A response in the form of deposition of brown material, presumedto be melanin, along the outer and inner walls of cells at thewound surface was observed within 3 d of impact. This materialeventually became granular in appearance. Formation of a ligno-suberizedboundary layer from cells present at the time of impact firstoccurred in 16-week-old roots 9 d after impact. Intensity ofcalcofluor fluorescence supported the findings made using lightmicroscopy. As wound healing progressed with time, the intensityof calcofluor fluorescence declined, demonstrating interferenceby wound healing products with calcofluor binding. Aggressiveharvest and subsequent storage dramatically reduced calcofluorfluorescence indicating that this dye may have potential valuein the assessment of tissue damage. Copyright 2001 Annals ofBotany Company Sugar beet, wound healing, impact damage, bruising, fluorescence, calcofluor, lignin 相似文献
988.
Abdel-Fattah S.A. Saad Magdy A. Massoud Hala S. Ibrahim 《Archives Of Phytopathology And Plant Protection》2013,46(8):955-962
An experimental study was carried out in pots to investigate the activity of Nemathorin, natural product and biopesticides against root-knot nematodes (RKNs) on tomatoes. Fosthiazate and abamectin proved to be the most effective treatments which suppressed the RKN population by 82.1%. Furthermore, arbuscular mycorrhizal fungus 2 (AMF2) was the superior treatment that reduced galls/root system followed by abamectin with the values of 72.5% and 67.2%, respectively. In addition, fosthiazate, cadusafos and crustacean2 gave the highest increase in the root length with the values of 55.8%, 54.6% and 54.6%, respectively. AMF2 was the most effective treatment which increases the root weight by 43.9%, while azadirachtin decreased the rootweight by 12.2% compared to untreated check. AMF2, cadusafos and crustacean2 not only increased the shoot length but also increased the shoot weight. Azadirachtin recorded the minimum increase in shoot system length and weight. 相似文献
989.
Haque Ehfazul Bari Md. Sazzadul Khandokar Labony Anjum Juhaer Jantan Ibrahim Seidel Veronique Haque Md. Areeful 《Phytochemistry Reviews》2023,22(1):211-273
Phytochemistry Reviews - Tinospora crispa (L.) Hook. f. & Thomson (Menispermaceae) is a plant indigenous to Africa and South-East Asia. It is widely used in ethnomedicine to alleviate... 相似文献
990.
Sedat Sevin Asuman Deveci Ozkan Hidayet Tutun Ibrahim Kivrak Ozge Turna Gamze Guney Eskiler 《化学与生物多样性》2023,20(3):e202201263
Honeybees provide multiple products such as bee venom (BV) which are used for various nutritional and medicinal purposes. BV has received great attention due to its wide range of bioactive components with potential anti-cancer effects on different cancers. Triple negative breast cancer (TNBC) is defined as an aggressive type of breast cancer and new therapeutic targets are required for its treatment. In the current literature information is varied about the composition and quantity of BV bioactive compounds as well as the origin of BV and its significance. In this context, the cytotoxic and apoptotic effects of BV with a higher rate of mellitin from Apis mellifera anatoliaca (Muğla ecotype) on MDA-MB-231 cells was evaluated, in vitro. The cytotoxic, apoptotic and morphological effects of BV were determined by WST-1, Annexin V, cell cycle analysis and Acridine Orange staining. The results showed that BV caused apoptotic cell death in TNBC cells at a lower dose (0.47 μg/mL, p<0.01). This study suggests that BV could be developed as a potential therapeutic agent for cancer treatment. However, the mechanism of BV-induced apoptosis death should be clarified at the molecular level. 相似文献