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161.
Heidari MM Houshmand M Hosseinkhani S Nafissi S Scheiber-Mojdehkar B Khatami M 《Cellular and molecular neurobiology》2009,29(2):225-233
Friedreich’s ataxia (FRDA) is an autosomal recessive neurodegenerative disorder caused by decreased expression of the protein
Frataxin. Frataxin deficiency leads to excessive free radical production and dysfunction of chain complexes. Mitochondrial
DNA (mtDNA) could be considered a candidate modifier factor for FRDA disease, since mitochondrial oxidative stress is thought
to be involved in the pathogenesis of this disease. It prompted us to focus on the mtDNA and monitor the nucleotide changes
of genome which are probably the cause of respiratory chain defects and reduced ATP generation. We searched about 46% of the
entire mitochondrial genome by temporal temperature gradient gel electrophoresis (TTGE) and DNA fragments showing abnormal
banding patterns were sequenced for the identification of exact mutations. In 18 patients, for the first time, we detected
26 mtDNA mutations; of which 5 (19.2%) was novel and 21 (80.8%) have been reported in other diseases. Heteroplasmic C13806A
polymorphisms were associated with Iranian FRDA patients (55.5%). Our results showed that NADH dehydrogenase (ND) genes mutations
in FRDA samples were higher than normal controls (P < 0.001) and we found statistically significant inverse correlation (r = −0.8) between number of mutation in ND genes and age of onset in FRDA patients. It is possible that mutations in ND genes
could constitute a predisposing factor which in combination with environmental risk factors affects age of onset and disease
progression. 相似文献
162.
In the current study, midgut α-amylase from Sunn pest ( Eurygaster integriceps Puton) (Hemiptera: Scutelleridae), one of the most serious pests of wheat and barley in the wide area of the Near and Middle East, West Asia, and many of the new independent states of central Asia, were purified and characterized. Amylase activity was detected in the midgut of the insects which were collected from both over-wintering sites during winter and feeding insects during spring. Amylase activities in the midgut of over-wintering and feeding insects were 5.71 and 3.43 U/mg protein, respectively. Initially, a native electrophoretic analysis of E. integriceps crude midgut extract showed that there are two major amylase forms in the midgut. Through the sequence of ammonium sulfate precipitation, first by gel filtration chromatography (Sephadex G-75), anion exchange chromatography (diethylaminoethylcellulose) and second by gel filtration chromatography, specific activity of α-amylase of E. integriceps increased 44-fold from approximately 3 to 133 U/mg protein. Analysis of purified amylases by sodium dodecylsulfate polyacrylamide gel electrophoresis showed that these proteins had estimated molecular masses of 49 and 52 kDa. Optimum temperature was determined to be 30–40°C. The optimum pH value was 6.5 and the K mapp for soluble starch was 0.54%. 相似文献
163.
Hasan Jalili Seyed H. Razavi Mohammad Safari F. Xavier Malcata 《Enzyme and microbial technology》2009,45(6-7):469-476
The behavior of Bifidobacterium animalis subsp. lactis Bb 12 under batch cultivation, after continuous culturing for up to 12 d, was monitored in skim milk-based media. Previous continuous culture for longer than 6 d affected the physiology of said microorganism. The minimum inhibitory concentrations of lactic and acetic acids increased from 18 to 26 g/l, whereas the molar ratio of acetic to lactic acid increased from 0.8 to 1.55, when the previous continuous culture increased its duration from 1 to 12 d. The specific lactose consumption rate decreased from 0.94 to 0.77 glactose/gcell dry mass/h within the batch culture timeframe; this was concomitant with greater amounts of acetic and formic acids, and lower amounts of lactic acid produced. The β-galactosidase activity increased as continuous culturing time increased, and reached 446 units/ml by 12 d; however, the rate of enzyme synthesis decreased concomitantly. Succinic acid was produced during the exponential growth and stationary phases of the batch culture, but the former at exponential growth phase was higher as the continuous culturing time was longer. For comparison purposes, batch cultivation of samples taken from continuous cultures by 1 and 12 d was done using a semi-synthetic medium with glucose as carbon source; a pattern similar to that observed when using skim milk-based media was observed. 相似文献
164.
Prolactin induces MFG-E8 production in macrophages via transcription factor C/EBPβ-dependent pathway
Aziz MM Ishihara S Rumi MA Mishima Y Oshima N Kadota C Moriyama I Li YY Rahman FB Otani A Oka A Ishimura N Kadowaki Y Amano Y Kinoshita Y 《Apoptosis : an international journal on programmed cell death》2008,13(5):609-620
The lactogenic hormone prolactin (PRL) regulates milk protein gene expression in mammary glands. To maintain homeostatic balance
in the body, milk fat globule epidermal growth factor 8 (MFG-E8) is vital for phagocytic clearance of apoptotic cells. We
investigated the effects of PRL on MFG-E8 expression in macrophages by evaluating its promoter function. Macrophages were
stimulated with PRL, and the expression of MFG-E8 was determined using real-time PCR and Western blotting. The role of MFG-E8
on phagocytosis of apoptotic cells in PRL-treated macrophages was assessed using microscopy, while the response of PRL to
MFG-E8 expression was evaluated using luciferase assay. Following treatment with PRL, significant up-regulations of the PRL
receptor and MFG-E8 were observed in macrophages, though PRL-treated macrophages more efficiently engulfed apoptotic cells.
The results of MFG-E8 promoter analysis showed considerable up-regulation of promoter activity in macrophages following PRL
treatment and results from mutation analysis of the MFG-E8 promoter suggested that the C/EBPβ binding site was responsible
for PRL-induced activation of the MFG-E8 promoter. C/EBPβ activity was found to be up-regulated in PRL-treated cells as revealed
by an electrophoretic mobility shift assay (EMSA). In conclusion, PRL is a potent inducer of MFG-E8 expression in macrophages,
while its effect is mediated by the presence of a responsive element in the MFG-E8 promoter. 相似文献
165.
Sherafat MA Javan M Mozafari S Mirnajafi-Zadeh J Motamedi F 《Neurochemical research》2011,36(10):1887-1895
Multiple sclerosis (MS) is a demyelinating disease that affects the central nervous system. MS is the most common neurological
disorder in young adults with a greater incidence among females. Male gonadal hormones have a protective effect on neural
system development and myelin maturation. In this study, we investigate the effect of castration on lysolecithin-induced demyelination
and remyelination processes using visual evoked potentials, in addition to measuring the expressions of Olig2, MBP, Nogo-A
and GFAP mRNAs as oligodendrocyte or astrocyte markers; and histological assessments by myelin-specific staining. We observed
more expanded demyelination with delayed repair process in castrated rats. Expression levels of the aforementioned marker
genes confirmed histological and electrophysiological observations. Our results showed a pivotal role for endogenous male
hormones in the context of demyelinating insults. It may also account for the different prognosis of MS between male and female
genders and provide new insights for therapeutic treatments. 相似文献
166.
Mojtaba Tabatabaei Yazdi Younes Ghasemi Abdollah Ghasemian Shadman Shokravi Hossein Niknahad Mohsen Amini Ali Dehshahri Mohammad Ali Faramarzi 《World journal of microbiology & biotechnology》2005,21(6-7):811-814
Summary The bioconversion of hydrocortisone by a locally isolated strain of cyanobacterium Fischerella ambigua PTCC 1635 was investigated. Fischerella ambigua had not been previously examined for this potential. The fermentation led to production of 11β,17α, 20β, 21-tetrahydroxypregn-4-en-3-one and 11β-hydroxyandrost-4-en-3,17-dione. The metabolites were isolated and purified by chromatographic methods and identified using
instrumental analyses. 相似文献
167.
Mishra JK Garg P Dohare P Kumar A Siddiqi MI Ray M Panda G 《Bioorganic & medicinal chemistry letters》2007,17(5):1326-1331
A series of 3-substituted 1,4-benzodiazepin-2-ones derived from S and R amino acids were evaluated for their anti-ischemic activity in vitro. Treatment with compounds 7h, 16, 9d, and 17 decreased the apoptotic neuronal number, however increased the neuronal viability. The compounds decreasing apoptosis could protect neurons from the ischemic injury. The difference in the activities of 1,4-benzodiazepin-2-ones derived from S- and R-amino acids is discussed and explained on the basis of molecular modeling studies. 相似文献
168.
Nourbakhsh N Soleimani M Taghipour Z Karbalaie K Mousavi SB Talebi A Nadali F Tanhaei S Kiyani GA Nematollahi M Rabiei F Mardani M Bahramiyan H Torabinejad M Nasr-Esfahani MH Baharvand H 《The International journal of developmental biology》2011,55(2):189-195
Stem cells from human exfoliated deciduous teeth (SHED) are highly proliferative, clonogenic and multipotent stem cells with a neural crest cell origin. Additionally, they can be collected with minimal invasiveness in comparison with other sources of mesenchymal stem cells (MSCs). Therefore, SHED could be a desirable option for potential therapeutic applications. In this study, SHEDs were established from enzyme-disaggregated deciduous dental pulp obtained from 6 to 9 year-old children. The cells had typical fibroblastoid morphology and expressed antigens characteristic of MSCs, STRO1, CD146, CD45, CD90, CD106 and CD166, but not the hematopoietic and endothelial markers, CD34 and CD31, as assessed by FACS analysis. Differentiation assessment revealed a strong osteogenic and adipogenic potential of SHEDs. In order to further evaluate the in vitro differentiation potential of SHED into neural cells, a simple short time growth factor-mediated induction was used. Immunofluorescence staining and flow cytometric analysis revealed that SHED rapidly expressed nestin and b-III tubulin, and later expressed intermediate neural markers. In addition, the intensity and percentages of nestin and b-III tubulin and mature neural markers (PSA-NCAM, NeuN, Tau, TH, or GFAP) increased significantly following treatment. Moreover, RT-PCR and Western blot analyses showed that the neural markers were strongly up-regulated after induction. In conclusion, these results provide evidence that SHED can differentiate into neural cells by the expression of a comprehensive set of genes and proteins that define neural-like cells in vitro. SHED cells might be considered as new candidates for the autologous transplantation of a wide variety of neurological diseases and neurotraumatic injuries. 相似文献
169.
170.
Ablation of PGC-1beta results in defective mitochondrial activity, thermogenesis, hepatic function, and cardiac performance 下载免费PDF全文
Lelliott CJ Medina-Gomez G Petrovic N Kis A Feldmann HM Bjursell M Parker N Curtis K Campbell M Hu P Zhang D Litwin SE Zaha VG Fountain KT Boudina S Jimenez-Linan M Blount M Lopez M Meirhaeghe A Bohlooly-Y M Storlien L Strömstedt M Snaith M Oresic M Abel ED Cannon B Vidal-Puig A 《PLoS biology》2006,4(11):e369