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861.
Sina Jasim Kepal N. Patel Gregory Randolph Stephanie Adams Roberto Cesareo Edward Condon Tara Henrichsen Malak Itani Maria Papaleontiou Leonardo Rangel John Schmitz Marius N. Stan 《Endocrine practice》2022,28(4):433-448
ObjectiveThe objective of this disease state clinical review is to provide clinicians with a summary of the nonsurgical, minimally invasive approaches to managing thyroid nodules/malignancy, including their indications, efficacy, side effects, and outcomes.MethodsA literature search was conducted using PubMed and appropriate key words. Relevant publications on minimally invasive thyroid techniques were used to create this clinical review.ResultsMinimally invasive thyroid techniques are effective and safe when performed by experienced centers. To date, percutaneous ethanol injection therapy is recommended for recurrent benign thyroid cysts. Both ultrasound-guided laser and radiofrequency ablation can be safely used for symptomatic solid nodules, both toxic and nontoxic. Microwave ablation and high-intensity focused ultrasound are newer approaches that need further clinical evaluation. Despite limited data, encouraging results suggest that minimally invasive techniques can also be used in small-size primary and locally recurrent thyroid cancer.ConclusionSurgery and radioiodine treatment remain the conventional and established treatments for nodular goiters. However, the new image-guided minimally invasive approaches appear safe and effective alternatives when used appropriately and by trained professionals to treat symptomatic or enlarging thyroid masses. 相似文献
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863.
Patrick Slama Jean-Luc Boucher Marius Réglier 《Journal of inorganic biochemistry》2009,103(3):455-462
N-Aryl-N′-hydroxyguanidines are compounds that display interesting pharmacological properties but their chemical reactivity remains poorly investigated. Some of these compounds are substrates for the heme-containing enzymes nitric-oxide synthases (NOS) and act as reducing co-substrates for the copper-containing enzyme Dopamine β-Hydroxylase (DBH) [P. Slama, J.L. Boucher, M. Réglier, Biochem. Biophys. Res. Commun. 316 (2004) 1081-1087]. DBH catalyses the hydroxylation of the important neurotransmitter dopamine into norepinephrine in the presence of both molecular oxygen and a reducing co-substrate. Although many molecules have been used as co-substrates for DBH, their interaction at the active site of DBH and their role in mechanism are not clearly characterized. In the present paper, we have used a water-soluble copper-N3S complex that mimics the CuB site of DBH, and aromatic N-hydroxyguanidines as reducers to address this question. N-Aryl-N′-hydroxyguanidines readily reduced copper(II) to Cu(I) and were oxidized into a nitrosoamidine as previously observed in reactions performed with purified DBH. These data describe for the first time the reactivity of N-aryl-N′-hydroxyguanidines with a water-soluble copper(II) complex and help to understand the interaction of co-substrates with copper at the active site of DBH. 相似文献
864.
Two serotype 1 strains ofLegionella pneumophila, Phildelphia 2 and Bellingham, were tested for their ability to metabolize five common substrates by measuring14CO2 released and14C-carbon incorporated into macromolecules. No major differences were noted between the two strains or preparations grown in
the yolk sac of chick embryos or agar-broth diphasic medium, following 2 or 14 pasaages on agar. Glutamate was the most actively
metabolized substrate, followed by glutamine. Acetate, glucose, and succinate were utilized at much more moderate rates. Changes
in cell density and substrate concentration altered the channeling of glutamate and glucose into CO2 and macromolecules. Specific CO2 felease from glutamate was greatest at low cell density and high substrate concentration, while carbon incorporation was
increased at high substrate concentration. A reciprocal relationship was noted with glucose: the proportion of carbon incorporation
was enhanced at low substrate concentration, but CO2 release paralleled increases in substrate concentration. The pH optimum for glutamate carbon incorporation and CO2 release was 5.5 and 6.1, respectively, but 25% of both activities were retained at pH 3.1. CO2 release from glucose was maximal at pH 7.5 with negligible activity at pH 3.1. Pathways of glucose metabolism were explored
by employing glucose, glucose-1-phosphate, and glucose-6-phosphate labeled in various carbon positions. The glycolytic pathway
appeared to play a lesser role than the pentose phosphate and/or Entner-Doudoroff pathways. Glucose-1-phosphate was metabolized
at a much higher rate than glucose or glucose-6-phosphate. We conclude that glutamate is utilized primarily as an energy source
while glucose may serve as an important metabolite for the nutrition ofL. pneumophila. 相似文献
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867.
Marijana Samardzija Andrea Corna Raquel Gomez-Sintes Mohamed Ali Jarboui Angela Armento Jerome E. Roger Eleni Petridou Wadood Haq Francois Paquet-Durand Eberhart Zrenner Pedro de la Villa Günther Zeck Christian Grimm Patricia Boya Marius Ueffing Dragana Trifunovi 《Cell death and differentiation》2021,28(4):1317
Cone photoreceptor cell death in inherited retinal diseases, such as Retinitis Pigmentosa (RP), leads to the loss of high acuity and color vision and, ultimately to blindness. In RP, a vast number of mutations perturb the structure and function of rod photoreceptors, while cones remain initially unaffected. Extensive rod loss in advanced stages of the disease triggers cone death by a mechanism that is still largely unknown. Here, we show that secondary cone cell death in animal models for RP is associated with increased activity of histone deacetylates (HDACs). A single intravitreal injection of an HDAC inhibitor at late stages of the disease, when the majority of rods have already degenerated, was sufficient to delay cone death and support long-term cone survival in two mouse models for RP, affected by mutations in the phosphodiesterase 6b gene. Moreover, the surviving cones remained light-sensitive, leading to an improvement in visual function. RNA-seq analysis of protected cones demonstrated that HDAC inhibition initiated multi-level protection via regulation of different pro-survival pathways, including MAPK, PI3K-Akt, and autophagy. This study suggests a unique opportunity for targeted pharmacological protection of secondary dying cones by HDAC inhibition and creates hope to maintain vision in RP patients even in advanced disease stages.Subject terms: Neuroscience, Neurological disorders 相似文献
868.
Wen Jie Zhang Frank T. Christiansen Xiongwen Wu Lawrence J. Abraham Marius Giphart Roger L. Dawkins 《Immunogenetics》1993,37(3):170-176
The evolutionary relationship between two central major histocompatibility complex (MHC) genes, C4 and CYP21, was investigated by employing pulsed field gel electrophoresis (PFGE) and conventional restriction fragment length polymorphism (RFLP) analyses in human and nonhuman primates. Using Taq I in conjunction with C4 and CYP21 probes, it has been found that there are four major types of C4 genes [defined by 7.0, 6.4, 6.0, and 5.4 kilobases (kb) Taq I fragments] and two major types of CYP21 genes (3.7 and 3.2 kb fragments) in human and nonhuman primates including chimpanzee, gorilla, and orangutan. All of the eight possible combinations of C4 and CYP21 genes can be identified on one or more human ancestral haplotypes (AH). It is concluded that each of the major types of C4 and CYP21 (and each of the combinations between these) predated human speciation. PFGE analysis with Mlu I and Pvu I suggested that each C4 + CYP21 segment has a specific length of 30–50 kb and that each AH carries one, two, three, or even more segments. In the case of C4, it is important to note that there is no simple relationship between the RFLP and the protein classifications. Thus, at least some of the expressed polymorphisms could be relatively recent in that they are carried by the same or different gene types. These findings are consistent with the hypothesis that M MHC AHs have been formed from a large pool of specific genomic segments and that further haplospecific polymorphism has developed subsequently. 相似文献