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51.
The rupture of a cerebral aneurysm is the most common cause of subarachnoid hemorrhage. Endovascular embolization of the aneurysms by implantation of Guglielmi detachable coils (GDC) has become a major treatment approach in the prevention of a rupture. Implantation of the coils induces formation of tissues over the coils, embolizing the aneurysm. However, blood entry into the coiled aneurysm often occurs due to failures in the embolization process. Current diagnostic methods used for aneurysms, such as X-ray angiography and computer tomography, are ineffective for continuous monitoring of the disease and require extremely expensive equipment. Here we present a novel technique for wireless monitoring of cerebral aneurysms using implanted embolization coils as radiofrequency resonant sensors that detect the blood entry. The experiments show that commonly used embolization coils could be utilized as electrical inductors or antennas. As the blood flows into a coil-implanted aneurysm, parasitic capacitance of the coil is modified because of the difference in permittivity between the blood and the tissues grown around the coil, resulting in a change in the coil's resonant frequency. The resonances of platinum GDC-like coils embedded in aneurysm models are detected to show average responses of 224–819 MHz/ml to saline injected into the models. This preliminary demonstration indicates a new possibility in the use of implanted GDC as a wireless sensor for embolization failures, the first step toward realizing long-term, noninvasive, and cost-effective remote monitoring of cerebral aneurysms treated with coil embolization.  相似文献   
52.
Graves' disease (GD) is the most common cause of thyrotoxicosis and often involves the orbits. Graves' ophthalmopathy (GO), also known as Thyroid Eye Disease (TED), can be clinically significant and advance to sight-threatening stages. Our knowledge of the immunogenetic pathophysiology of GO is rapidly expanding. The present review is an attempt to summarize the current state of knowledge on the immunogenetics of GO. First we briefly review the epidemiology and clinical importance of GO, and then we describe in detail the macromolecular pathogenesis and finally immunogenetics of GO. Discrepancies between the results from various reports and the limitations of the available data are discussed. In particular, there is a scarcity of data from non-Asian populations. While several studies have demonstrated significant associations between polymorphisms in certain genes (especially CTLA-4, HLA-DRB-1, and TNF-α), there is a need for studies that investigate the relationship between polymorphisms and both serum and local concentrations of the resulting proteins. A complete understanding of GO susceptibility and pathogenesis has not been yet possible due to a number of important knowledge gaps that need to be filled by future research.  相似文献   
53.
Glucarpidase (former name: carboxypeptidase G2, or CPG2) is a bacterial enzyme that is widely used in detoxification of the cytotoxic drug, methotrexate, and in Antibody Directed Enzyme Prodrug Therapy for cancer treatment. The glucarpidase gene of Pseudomonas sp. strain RS-16 was previously cloned in E coli, but expresses at a level that is approximately 100-fold lower than in the native strain. In this study, a synthetic gene coding for glucarpidase was codon-optimised and synthesized for maximum expression in E. coli using the vector pET28a. Our work indicated that the enzyme was expressed to ~60% of the total host protein and that purification of the recombinant His-tagged protein could be achieved in a single step by Ni2+ charged column chromatography. The synthetic recombinant glucarpidase expressed within this system was biologically active and zinc dependant. Our study showed that Mg2+ as well as Mn2+ ions inhibit the activity of the recombinant enzyme.  相似文献   
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Upper Permian (Murghabian) sponges from the Surmaq Formation exposed in the Hambast Mountains, south of Abadeh, central Iran are described. The sponge fauna of the Surmaq Formation is composed of at least 26 taxa, including 12 species of sphinctozoans, 12 species of inozoans, one operculospongid, and one lithistid species. The following taxa were determined to genus or species level: Sphinctozoa: Family Sebargasiidae: Amblysiphonella hambastensis n. sp., Discosiphonella iranica n. sp., Family Colospongiidae: Colospongia cortexifera Senowbari-Daryan and Rigby, Exaulipora permica (Senowbari-Daryan), Platythalamiella sp. 1, Platythalamiella? sp. 2, Parauvanella minima Senowbari-Daryan, Colospongia? or Neoguadalupia? sp., Family Guadalupiidae: Cystothalamia surmaqensis n. sp., Imbricatocoelia cf. paucipora Rigby, Fan and Zhang, Family Thaumastocoeliidae: Sollasia ostiolata Steinmann, Family Cryptocoeliidae: Stylocoelia circopora Wu. Inozoa: Family Peronidellidae: Preperonidella cf. Preperonidella recta grossa (Wu), Heptatubispongia symmetrica Rigby and Senowbari-Daryan, Hambastella sincassa n. gen., n. sp., Hambastella cumcassa n. sp., Family Maeandrostiidae: Maeandrostia kansasensis Girty, Maeandrostia? dubia n. sp., Surmaqella pustulata n. gen., n. sp., Family Auriculospongiidae: Pseudopalaeoaplysina huayingensis Wang, Qiang and Zhang, Family Disjectoporidae: Disjectopora beipeiensis Fan, Rigby and Zhang, Lichuanopora cf. bancaoensis Fan, Rigby and Zhang, Family Khmeriidae: Imilce newelli Flügel. Lithistida: Family Astylospongiidae: Raanespongia iranica n. sp. Among the sphinctozoans A. hambastensis n. sp. is an extremely abundant species. Among the inozoans the genus Hambastella n. gen., with both species, is the most abundant genus. The genera Disjectopora, Lichuanopora, and Pseudopaleoaplysina, were described as hydrozoans by early workers, but are assigned to the inozoans in this paper. The Upper Permian sponge fauna, as well as the composition of other reef organisms, from the Hambast Mountains in central Iran is different from that of the assemblage in the Lower Permian reefal limestones of Bagh-e Vang from the Shotori Mountians (northeast Iran).  相似文献   
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Non–small-lung cancer (NSCLC) is the leading cause of cancer death. Early detection of NSCLC could pave the way for effective therapies. Analysis of molecular genetic biomarkers in biological fluids has been proposed as a useful tool for cancer diagnosis. Here, we aimed to develop a panel of noncoding RNAs (ncRNAs) in sputum for NSCLC early detection. Expression of 11 ncRNAs were analyzed by real–time polymerase chain reaction in sputum samples of 30 NSCLC patients and 30 sex- and age-matched cancer-free controls. Stability of endogenous microRNAs (miRNAs) in sputum was evaluated after 3 and 6 days at 4°C, 6 months, and 1 year at −80°C. Nine ncRNAs showed significant differences of their expression in sputum between NSCLC patients and controls. A logistic regression model with the best prediction was built based on miR-145, miR-126, and miR-7. The composite of the three miRNAs produced 90% sensitivity and specificity in distinguishing NSCLC patients from the controls. Results indicate that miRNAs could be useful biomarkers based on their stability under various storage conditions and maintain differential changes between cancer and control groups. Moreover, measurement of miRNAs in sputum could be a noninvasive approach for detection of lung cancer.  相似文献   
58.
Lineweaver-Burk plot analysis is the most widely used method to determine enzyme kinetic parameters. In the spectrophotometric determination of enzyme activity using the Lineweaver-Burk plot, it is necessary to find a wavelength at which only the substrate or the product has absorbance without any spectroscopic interference of the other reaction components. Moreover, in this method, different initial concentrations of the substrate should be used to obtain the initial velocities required for Lineweaver-Burk plot analysis. In the present work, a multi-wavelength model-based method has been developed and validated to determine Michaelis-Menten constants for some enzyme reactions. In this method, a selective wavelength region and several experiments with different initial concentrations of the substrate are not required. The absorbance data of the kinetic assays are fitted by non-linear regression coupled to the numeric integration of the related differential equation. To indicate the applicability of the proposed method, the Michaelis-Menten constants for the oxidation of phenanthridine, 6-deoxypenciclovir and xanthine by molybdenum hydroxylases were determined using only a single initial concentration of the substrate, regardless of any spectral overlap.  相似文献   
59.
A mathematical model using simple concepts of repeated games is proposed to model the course and prognosis of factitious disorders. Although simple, the model seems capable of explaining the yet unknown mechanisms underlying the variable course of factitious disorders. One of the notable results of this study is the significant effect of involved physicians in the treatment process on the course of the disease. Particularly, the doctor's error rate in realizing whether the symptoms are real or factitious can considerably affect the course of the disease. This is the first paper to apply a mathematical model to factitious disorders.  相似文献   
60.
Calcareous algae and microproblematica have been studied in the Middle Permian part of the Dalan Formation in Dena Mountain, Zagros, southwest Iran. Murgabian (=Wordian) microfossils are the most diversified. The assemblages encompass, among the dasycladales, Anthracoporella spectabilis, Epimastopora piae, Epimastoporella japonica, E. likana, Paraepimastopora? cf. densipora n. comb., Gyroporella cf. nipponica, G.? aff. fluegeli n. comb., G.? aff. symmetrica, G.? aff. digitula n. comb., Mizzia yabei; among the gymnocodiaceans, Gymnocodium bellerophontis, G. nodosum, Permocalculus cf. digitatus, P. forcepinus, P. cf. fragilis, P. plumosus, P. cf. solidus, Tauridium? sp.; among the “phylloid algae” Eugonophyllum? sp.; among the other incertae sedis algae Stacheoides sp., Ungdarella uralica, Fourstonella (Efluegelia) johnsoni, and among some microproblematica alternatively assigned to foraminifers or algae Aeolisaccus dunningtoni, Tubiphytes obscurus, Pseudovermiporella nipponica, P. sodalica, and P. longipora. Each taxon is briefly characterized, whereas a more detailed analysis of the epimastoporacean algae is given. Among them, the genera Epimastopora and Epimastoporella are emended. All the described microfossils have a relatively broad stratigraphic distribution in the Permian period but they are paleoecologically important. They are indeed confident micropaleontological Middle Permian proxies, particularly for shallow-marine, warm, well-oxygenated and relatively high-energy environments. They were affected by the end-Guadalupian crisis because they strongly decrease in the upper carbonate unit of the Dalan Formation and are not found in the Triassic sediments of the area.  相似文献   
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