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91.
Vincent EJ Jassey Geneviève Chiapusio Philippe Binet Alexandre Buttler Fatima Laggoun‐Défarge Frédéric Delarue Nadine Bernard Edward AD Mitchell Marie‐Laure Toussaint André‐Jean Francez Daniel Gilbert 《Global Change Biology》2013,19(3):811-823
Peatlands contain approximately one third of all soil organic carbon (SOC). Warming can alter above‐ and belowground linkages that regulate soil organic carbon dynamics and C‐balance in peatlands. Here we examine the multiyear impact of in situ experimental warming on the microbial food web, vegetation, and their feedbacks with soil chemistry. We provide evidence of both positive and negative impacts of warming on specific microbial functional groups, leading to destabilization of the microbial food web. We observed a strong reduction (70%) in the biomass of top‐predators (testate amoebae) in warmed plots. Such a loss caused a shortening of microbial food chains, which in turn stimulated microbial activity, leading to slight increases in levels of nutrients and labile C in water. We further show that warming altered the regulatory role of Sphagnum‐polyphenols on microbial community structure with a potential inhibition of top predators. In addition, warming caused a decrease in Sphagnum cover and an increase in vascular plant cover. Using structural equation modelling, we show that changes in the microbial food web affected the relationships between plants, soil water chemistry, and microbial communities. These results suggest that warming will destabilize C and nutrient recycling of peatlands via changes in above‐ and belowground linkages, and therefore, the microbial food web associated with mosses will feedback positively to global warming by destabilizing the carbon cycle. This study confirms that microbial food webs thus constitute a key element in the functioning of peatland ecosystems. Their study can help understand how mosses, as ecosystem engineers, tightly regulate biogeochemical cycling and climate feedback in peatlands 相似文献
92.
Khalid K Alharbi Imran Ali Khan Nasser M Al-Daghri Anjana Munshi Vandana Sharma Abdul Khader Mohammed Kaiser A Wani Yazeed A Al-Sheikh May Salem Al-Nbaheen Mohammed Ghouse Ahmed Ansari Rabbani Syed 《Journal of biosciences》2013,38(5):893-897
Type 2 diabetes mellitus (T2DM) is a disease induced by complex interactions between environmental factors and certain genetic factors. Genetic variants in the Adenosine Binding Cassette Transporter Proteins 1 (ABCA1) have been associated with abnormalities of serum lipid levels of high-density lipoprotein (HDL-C). Decreased serum levels of HDL-C have often been observed in T2DM cases, and this condition has been considered to be involved in the mechanism of insulin resistance (IR). Therefore, we investigated possible association between ABCA1 C69T gene polymorphism and T2DM in a Saudi population. This study was carried out with 380 healthy control subjects and 376 T2DM patients. Genotyping of ABCA1 C69T polymorphism was carried out by Polymerase Chain Reaction-Restriction Fragment Length Polymorphism technique. We observed that the frequency of the T allele of the ABCA1 C69T gene was significantly higher in healthy subjects compared to T2DM patients (0.28 vs 0.45; p<0.0001; OR (95% CI) = 0.4624 (0.3732–0.5729), and therefore the T allele may be a protective factor against T2DM in the Saudi population. 相似文献
93.
Kaur Prabhsimran Kotru Sushil Singh Sandeep Behera Bidwan Sekhar Munshi Anjana 《Journal of physiology and biochemistry》2020,76(4):485-502
Journal of Physiology and Biochemistry - Diabetes, the most common endocrine disorder, also known as a silent killer disease, is characterized by uncontrolled hyperglycemia. According to the... 相似文献
94.
Yingxiang Li Xujun Wang Haiyang Zheng Chengyang Wang Stéphane Minvielle Florence Magrangeas Hervé Avet-Loiseau Parantu K. Shah Yong Zhang Nikhil C. Munshi Cheng Li 《PloS one》2013,8(3)
Multiple myeloma (MM) is a cancer of antibody-making plasma cells. It frequently harbors alterations in DNA and chromosome copy numbers, and can be divided into two major subtypes, hyperdiploid (HMM) and non-hyperdiploid multiple myeloma (NHMM). The two subtypes have different survival prognosis, possibly due to different but converging paths to oncogenesis. Existing methods for identifying the two subtypes are fluorescence in situ hybridization (FISH) and copy number microarrays, with increased cost and sample requirements. We hypothesize that chromosome alterations have their imprint in gene expression through dosage effect. Using five MM expression datasets that have HMM status measured by FISH and copy number microarrays, we have developed and validated a K-nearest-neighbor method to classify MM into HMM and NHMM based on gene expression profiles. Classification accuracy for test datasets ranges from 0.83 to 0.88. This classification will enable researchers to study differences and commonalities of the two MM subtypes in disease biology and prognosis using expression datasets without need for additional subtype measurements. Our study also supports the advantages of using cancer specific characteristics in feature design and pooling multiple rounds of classification results to improve accuracy. We provide R source code and processed datasets at www.ChengLiLab.org/software. 相似文献
95.
Wu YI Munshi HG Snipas SJ Salvesen GS Fridman R Stack MS 《The Biochemical journal》2007,407(2):171-177
The transmembrane collagenase MT1-MMP (membrane-type 1 matrix metalloproteinase), also known as MMP-14, has a critical function both in normal development and in cancer progression, and is subject to extensive controls at the post-translational level which affect proteinase activity. As zymogen activation is crucial for MT1-MMP activity, an alpha1-PI (alpha1-proteinase inhibitor)-based inhibitor was designed by incorporating the MT1-MMP propeptide cleavage sequence into the alpha1-PI reactive-site loop (designated alpha1-PI(MT1)) and this was compared with wild-type alpha1-PI (alpha1-PI(WT)) and the furin inhibitory mutant alpha1-PI(PDX). Alpha1-PI(MT1) formed an SDS-stable complex with furin and inhibited proMT1-MMP activation. A consequence of the loss of MT1-MMP activity was the activation of proMMP-2 and the inhibition of MT1-MMP-mediated collagen invasion. alpha1-PI(MT1) expression also resulted in the intracellular accumulation of a glycosylated species of proMT1-MMP that was retained in the perinuclear region, leading to significantly decreased cell-surface accumulation of proMT1-MMP. These observations suggest that both the subcellular localization and the activity of MT1-MMP are regulated in a coordinated fashion, such that proMT1-MMP is retained intracellularly until activation of its zymogen, then proMT1-MMP traffics to the cell surface in order to cleave extracellular substrates. 相似文献
96.
Lindsley SR Moore KP Rajapakse HA Selnick HG Young MB Zhu H Munshi S Kuo L McGaughey GB Colussi D Crouthamel MC Lai MT Pietrak B Price EA Sankaranarayanan S Simon AJ Seabrook GR Hazuda DJ Pudvah NT Hochman JH Graham SL Vacca JP Nantermet PG 《Bioorganic & medicinal chemistry letters》2007,17(14):4057-4061
This Letter describes the design and synthesis of tertiary carbinamine macrocyclic inhibitors of the beta-secretase (BACE-1) enzyme. These macrocyclic inhibitors, some of which incorporate novel P2 substituents, display a 2- to 100-fold increase in potency relative to the previously described acyclic analogs while affording greater stability. 相似文献
97.
Garbaccio RM Huang S Tasber ES Fraley ME Yan Y Munshi S Ikuta M Kuo L Kreatsoulas C Stirdivant S Drakas B Rickert K Walsh ES Hamilton KA Buser CA Hardwick J Mao X Beck SC Abrams MT Tao W Lobell R Sepp-Lorenzino L Hartman GD 《Bioorganic & medicinal chemistry letters》2007,17(22):6280-6285
From HTS lead 1, a novel benzoisoquinolinone class of ATP-competitive Chk1 inhibitors was devised and synthesized via a photochemical route. Using X-ray crystallography as a guide, potency was rapidly enhanced through the installation of a tethered basic amine designed to interact with an acidic residue (Glu91) in the enzyme pocket. Further SAR was explored at the solvent front and near to the H1 pocket and resulted in the discovery of low MW, sub-nanomolar inhibitors of Chk1. 相似文献
98.
Sneha Dadheech Suman Jain D. Madhulatha Vandana Sharma James Joseph A. Jyothy Anjana Munshi 《Molecular biology reports》2014,41(5):3331-3337
Haemoglobinopathies including β-thalassemia and sickle cell anaemia (SCA) are considered to be classical monogenic diseases. There is considerable clinical variability between patients inheriting identical β-globin mutations. The reasons for this variability are not well understood. Previous studies have suggested that a variety of genetic determents influence different clinical phenotypes. The genetic variants that modulate HbF levels have a very strong impact on ameliorating the clinical phenotype. In the present study 6,500 blood samples from suspected cases were analysed using HPLC, ARMS-PCR, RDB techniques. Patients with β-thalassemia and SCA were classified into mild, moderate, severe according to the severity score based on Hb levels, age of onset, age at which patients received their first blood transfusion, the degree of growth retardation and splenectomy. Patients with β-thalassemia and SCA were analysed for Xmn1 polymorphism and association between this polymorphism and severity of β-thalassemia and SCA was evaluated. We found a significant difference in genotypic and allelic frequencies of Xmn1 polymorphism between mild and moderate and mild and severe cases. There was a significant difference in high and low percentage of HbF in CC, CT and TT bearing individuals. The TT bearing individuals were found to have a high percentage of HbF in β-thalassemia as well as SCA. This study confirms that increased γG-globin expression associated with Xmn1 polymorphism ameliorates the clinical severity in β-thalassemia as well as SCA in the study population. 相似文献
99.
Khalid?Al AboudEmail author Daifullah?Al Aboud Sameer?Munshi Ali?assiry?Halawi 《Andrologie》2014,24(1):7
Andrology is the study of male reproductive health, its associated medicines, and biology, including functions and diseases that are specific to men, especially with regard to the reproductive organs. This concise report discusses the eponyms that are encountered in andrological literature. 相似文献
100.
Gowhar Shafi Anjana Munshi Tarique N Hasan Ali A Alshatwi A Jyothy David KY Lei 《Cancer cell international》2009,9(1):29-8