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991.
Design,synthesis, and characterization of α, β‐unsaturated carboxylic acid,and its urea based derivatives that explores novel epigenetic modulators in human non‐small cell lung cancer A549 cell line 下载免费PDF全文
992.
Neurochemical Research - The original version of this article unfortunately contained a mistake. The entries missing in the reference list are given below and their corresponding citations are... 相似文献
993.
Kadallipura Puttaswamy Rakesh Suhas Ramesh Shivakumar Dase Channe Gowda 《Russian Journal of Bioorganic Chemistry》2018,44(2):158-164
Peptides of relatively low charge and a high number of hydrophobic amino acids were designed. The amino acid sequence of designed peptides was GXGVP, where X equaled to W, Y, F, D, and T with a combination of hydrophobic, charged and polar units. These peptides were linked to quinazolinones to obtain a new class of compounds with synergistic features. The hybrids displayed antimicrobial activity against Gram-positive and Gram-negative bacteria. In particular, Trp, Tyr, and Phe-containing peptides showed greater antimicrobial potency than the reference standards. Alkyl chain length variations in heterocyclic moiety indicated that hybrids with propyl group were more active than butyl derivatives. Improved results were observed for debenzylated versions of the conjugates compared to their benzylated counterparts. Implementation of the hybrid structures of varying charge, hydrophobicity, and alkyl chain length would be a promising approach to obtaining effective antimicrobial agents. 相似文献
994.
Saeedi R Parsons HL Wambolt RB Paulson K Sharma V Dyck JR Brownsey RW Allard MF 《American journal of physiology. Heart and circulatory physiology》2008,294(6):H2497-H2506
The metabolic actions of the antidiabetic agent metformin reportedly occur via the activation of the AMP-activated protein kinase (AMPK) in the heart and other tissues in the presence or absence of changes in cellular energy status. In this study, we tested the hypothesis that metformin has AMPK-independent effects on metabolism in heart muscle. Fatty acid oxidation and glucose utilization (glycolysis and glucose uptake) were measured in isolated working hearts from halothane-anesthetized male Sprague-Dawley rats and in cultured heart-derived H9c2 cells in the absence or in the presence of metformin (2 mM). Fatty acid oxidation and glucose utilization were significantly altered by metformin in hearts and H9c2 cells. AMPK activity was not measurably altered by metformin in either model system, and no impairment of energetic state was observed in the intact hearts. Furthermore, the inhibition of AMPK by 6-[4-(2-piperidin-1-yl-ethoxy)-phenyl]-3-pyridin-4-yl-pyyrazolo[1,5-a] pyrimidine (Compound C), a well-recognized pharmacological inhibitor of AMPK, or the overexpression of a dominant-negative form of AMPK failed to prevent the metabolic actions of metformin in H9c2 cells. The exposure of H9c2 cells to inhibitors of p38 mitogen-activated protein kinase (p38 MAPK) or protein kinase C (PKC) partially or completely abrogated metformin-induced alterations in metabolism in these cells, respectively. Thus the metabolic actions of metformin in the heart muscle can occur independent of changes in AMPK activity and may be mediated by p38 MAPK- and PKC-dependent mechanisms. 相似文献
995.
Ahlawat Sonika Vijh Ramesh Kumar Sharma Anju Sharma Upasna Girdhar Yashila Kaur Mandeep Chhabra Pooja Kumar Ashish Arora Reena 《Molecular biology reports》2020,47(9):7029-7038
Molecular Biology Reports - The present study is an effort to understand the genomic drivers of lactation in Sahiwal (Bos indicus), the best milch cattle breed of the tropics. RNA sequencing of... 相似文献
996.
An oral sustained release dosage form of cinnarizine HCl (CNZ) based on gastric floating matrix tablets was studied. The release
of CNZ from different floating matrix formulations containing four viscosity grades of hydroxypropyl methylcellulose, sodium
alginate or polyethylene oxide, and gas-forming agent (sodium bicarbonate or calcium carbonate) was studied in simulated gastric
fluid (pH 1.2). CNZ release data from the matrix tablets were analyzed kinetically using Higuchi, Peppas, Weibull, and Vergnaud
models. From water uptake, matrix erosion studies, and drug release data, the overall release mechanism can be explained as
a result of rapid hydration of polymer on the surface of the floating tablet and formation of a gel layer surrounding the
matrix that controls water penetration into its center. On the basis of in vitro release data, batch HP1 (CNZ, HPMC-K100LV, SBC, LTS, and MgS) was subjected to bioavailability studies in rabbits and was
compared with CNZ suspension. It was concluded that the greater bioavailability of HP1 was due to its longer retention in
the gastric environment of the test animal. Batch no. HP1 of floating tablet in rabbits demonstrated that the floating tablet
CNZ could be a 24-h sustained release formulation. 相似文献
997.
Aravind L Mazumder R Vasudevan S Koonin EV 《Current opinion in structural biology》2002,12(3):392-399
Complementary developments in comparative genomics, protein structure determination and in-depth comparison of protein sequences and structures have provided a better understanding of the prevailing trends in the emergence and diversification of protein domains. The investigation of deep relationships among different classes of proteins involved in key cellular functions, such as nucleic acid polymerases and other nucleotide-dependent enzymes, indicates that a substantial set of diverse protein domains evolved within the primordial, ribozyme-dominated RNA world. 相似文献
998.
Gurumurthy S Goswami A Vasudevan KM Rangnekar VM 《Molecular and cellular biology》2005,25(3):1146-1161
Despite distinct dissimilarities, diverse cancers express several common protumorigenic traits. We present here evidence that the proapoptotic protein Par-4 utilizes one such common tumorigenic trait to become selectively activated and induce apoptosis in cancer cells. Elevated protein kinase A (PKA) activity noted in cancer cells activated the apoptotic function of ectopic Par-4 or its SAC (selective for apoptosis induction in cancer cells) domain, which induces apoptosis selectively in cancer cells and not in normal or immortalized cells. PKA preferentially phosphorylated Par-4 at the T155 residue within the SAC domain in cancer cells. Moreover, pharmacological-, peptide-, or small interfering RNA-mediated inhibition of PKA activity in cancer cells resulted in abrogation of both T155 phosphorylation and apoptosis by Par-4. The mechanism of activation of endogenous Par-4 was similar to that of ectopic Par-4, and in response to exogenous stimuli, endogenous Par-4 induced apoptosis by a PKA- and phosphorylated T155-dependent mechanism. Enforced elevation of PKA activity in normal cells resulted in apoptosis by the SAC domain of Par-4 in a T155-dependent manner. Together, these observations suggest that selective apoptosis of cancer cells by the SAC domain of Par-4 involves phosphorylation of T155 by PKA. These findings uncover a novel mechanism engaging PKA, a procancerous activity commonly elevated in most tumor cells, to activate the cancer selective apoptotic action of Par-4. 相似文献
999.
Subramani Ramesh Narayanasamy Mathivanan 《World journal of microbiology & biotechnology》2009,25(12):2103-2111
A total of 288 marine samples were collected from different locations of the Bay of Bengal starting from Pulicat lake to Kanyakumari,
and 208 isolates of marine actinomycetes were isolated using starch casein agar medium. The growth pattern, mycelial coloration,
production of exopolysaccharides and diffusible pigment and abundance of Streptomyces spp. were documented. Among marine actinomycetes, Streptomyces spp. were present in large proportion (88%). Among 208 marine actinomycetes, 111 isolates exhibited antimicrobial activity
against human pathogens, and 151 showed antifungal activity against two plant pathogens. Among 208 isolates, 183, 157, 116,
72 and 68 isolates produced lipase, caseinase, gelatinase, cellulase and amylase, respectively. The results of diversity,
antimicrobial activity and enzymes production have increased the scope of finding industrially important marine actinomycetes
from the Bay of Bengal and these organisms could be vital sources for the discovery of industrially useful molecules/enzymes. 相似文献
1000.
An alkalophilic Aspergillus nidulans KK-99 produced an alkaline, thermostable xylanase (40 IU/ml) in a basal medium supplemented with wheat bran (2% w/v) and KNO3 (at 0.15% N) pH 10.0 and 37 degrees C. The partially purified xylanase was optimally active at pH 8.0 and 55 degrees C. The xylanase was stable in a broad pH range of 4.0-9.5 for 1 h at 55 degrees C, retaining more than 80% of its activity. The enzyme exhibited greater binding affinity for xylan from hardwood than from softwood. The xylanase activity was stimulated (+25%) by Na+ and Fe2+ and was strongly inhibited (maximum by 70%) by Tween-20, 40, 60, SDS, acetic anhydride, phenylmethane sulphonyl fluoride, Triton-X-100. The xylanase dose of 1.0 IU/g dry weight pulp gave optimum bleach boosting of Kraft pulp at pH 8.0 and temperature 55 degrees C for 3 h reaction time. 相似文献