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131.
Endoscopic submucosal dissection (ESD) provides strong therapeutic benefits for early gastrointestinal cancer as a minimally invasive treatment. However, there is currently no reliable treatment to prevent scar contracture resulting from ESD which may lead to cicatricial stricture. Herein, a multifunctional colloidal wound dressing to promote tissue regeneration after ESD is demonstrated. This sprayable wound dressing, composed of hydrophobized microparticles, exhibits the multifunctionality necessary for wound healing including tissue adhesiveness, blood coagulation, re‐epithelialization, angiogenesis, and controlled inflammation based on hydrophobic interaction with biological systems. An in vivo feasibility study using swine gastric ESD models reveals that this colloidal wound dressing suppresses fibrosis and accelerates wound healing. Multifunctional colloidal and sprayable wound dressings have an enormous therapeutic potential for use in a wide range of biomedical applications including accelerated wound healing after ESD, prevention of perforation, and the treatment of inflammatory diseases.  相似文献   
132.
A multicenter cooperative phase I study of ZD-1694 (raltitrexed), a novel, folate-based thymidylate synthase (TS) inhibitor, was conducted with single and repeated doses in 30 patients with various malignant tumors. ZD-1694 was intravenously infused over 15 minutes. In the single-dose study, the initial dose was fixed at 1.0 mg/m2 (1n), and the dose was escalated stepwise up to 3.5 mg/m2 (3.5 n). Based on the results of the single-dose study, in the repeated-dose study, doses of 2.5 n and 3 n were infused every three weeks (3 weeks/one course). In principle, patients received 2 courses or more. Of the 29 eligible patients, 16 were in the single-dose study and 13 in the repeated-dose study. Adverse reactions were evaluated in all eligible patients. In the single-dose study, neutropenia, nausea/vomiting, diarrhea, and transaminase (GOT, GPT) increases, of grade 3 or higher, occurred at high doses of 3 n and 3.5 n. These were regarded as dose-limiting toxicities (DLT). DLT of grade 3 or higher were observed in 1 of 4 patients given 3 n and 2 of 4 patients given 3.5 n. These results suggested that the maximum tolerated dose (MTD) of ZD-1694 was 3.5 n (3.5 mg/m2). In the repeated-dose study, DLT of grade 3 or higher was observed in no more than one third of each dose group, 2 of the 6 patients given 2.5 n and 2 of the 7 patients given 3 n. These results suggested that 3 n (3.0 mg/m2), a dose nearer to MTD, was the recommended dose for the phase II study. Although transaminase increases were observed in all patients, in 12 of them the increase was grade 2 or lower and reversible. A pharmacokinetic investigation showed the mean elimination half life of ZD-1694 plasma concentration was 91.5 hours in the single-dose group and 119.1 hours in the repeated dose group. It was suggested that ZD-1694 is metabolized to polyglutamates after uptake and retained in the cells for a long duration. However, no accumulation was seen in plasma concentration of ZD-1694 following repeated doses at 3-weekly intervals. One PR was observed in a patient with colorectal cancer receiving 2.5 n in the repeated-dose study. Based on these results, the recommended dosage and administration for the phase II study of ZD-1694 was 3 n (3.0 mg/m2) intravenously infused over 15 minutes every 3 weeks.  相似文献   
133.
134.
We experienced 12 cases of congenital cystic adenomatoid malformation of the lung (CCAM) including 6 cases diagnosed antenatally. They were classified into three groups according to the clinical manifestations. Group A was associated with hydrops fetalis (n = 3), group B presented with respiratory distress symptoms after birth (n = 6), and group C showed no respiratory symptoms (n = 3). All cases of group A were lost because of hydrops and respiratory failure due to pulmonary hypoplasia. Because a compression of the mass is thought to be a cause of hydrops, this group is considered to be a good indication for fetal treatment. All cases of group B showed progressive respiratory symptoms a few days after birth which were successfully treated surgically. In 2 of 3 cases of group C, the lesions decreased in size both antenatally and postnatally. We conclude that serial sonographic evaluations for fetal CCAM are important. If the fetus develops hydrops, fetal surgery is to be considered. If not, however, fetal surgery should not be done, because some lesions can shrink in size, or even disappear, while others can be treated successfully after birth by lobectomy or even segmentectomy.  相似文献   
135.
Summary We studied high-molecular-weight α,β-PMA synthesized by polycondensation in order to find possible applications for biomaterials. Its solubility in different solvents, its hydrolysis and its acidity were also examined. The α,β-PMA molecular weight increased markedly up to 20 h and then decreased showing that the molecular weights for synthesized α,β-PMA depends on the reaction time. We prepared high-yield α,β-PMA with a molecular weight of 3600 by direct polycondensation using tin(II) chloride as a catalyst at 130°C for 20 hours and concluded that our method is suitable to synthesize higher molecular weight compounds of α,β-PMA. Received: 20 December 2002/Revised version: 18 February 2003/ Accepted: 22 February 2003 Correspondence to Tetsuto Kajiyama  相似文献   
136.
A comprehensive classification system for lipids   总被引:1,自引:0,他引:1  
Lipids are produced, transported, and recognized by the concerted actions of numerous enzymes, binding proteins, and receptors. A comprehensive analysis of lipid molecules, “lipidomics,” in the context of genomics and proteomics is crucial to understanding cellular physiology and pathology; consequently, lipid biology has become a major research target of the postgenomic revolution and systems biology. To facilitate international communication about lipids, a comprehensive classification of lipids with a common platform that is compatible with informatics requirements has been developed to deal with the massive amounts of data that will be generated by our lipid community. As an initial step in this development, we divide lipids into eight categories (fatty acyls, glycerolipids, glycerophospholipids, sphingolipids, sterol lipids, prenol lipids, saccharolipids, and polyketides) containing distinct classes and subclasses of molecules, devise a common manner of representing the chemical structures of individual lipids and their derivatives, and provide a 12 digit identifier for each unique lipid molecule. The lipid classification scheme is chemically based and driven by the distinct hydrophobic and hydrophilic elements that compose the lipid. This structured vocabulary will facilitate the systematization of lipid biology and enable the cataloging of lipids and their properties in a way that is compatible with other macromolecular databases.[Reprinted with copyright permission from the Journal of Lipid Research. 2005. 46: 839–861.]  相似文献   
137.
138.
To search for concomitant anomalies among babies with congenital hypothyroidism, 120 newborn babies with confirmed congenital hypothyroidism were studied at the Veterans General Hospital, Taipei. The incidence of concomitant anomalies was estimated to be 11.67% (14/120). Among these anomalies, cardiac and gastrointestinal systems were the most commonly involved, comprising 35.7% (5/14) and 28.6% (4/14) of all anomalies, respectively. The type (i.e. agenesis, ectopia or eutopic goiter) as well as the severity of hypothyroidism were analyzed between groups of babies with or without concomitant anomalies. No differences existed between the two groups of babies regarding these two aspects.  相似文献   
139.
Taguchi  M. Fujimoto  T. Tanaka  K. 《Electronics letters》1994,30(22):1815-1816
A coplanar waveguide fed active dipole antenna for a television receiver is fabricated on a thin dielectric film by using photoetching techniques. A transistor amplifier is integrated between the feeding point of the dipole and CPW. Actual gains of more than 8 dBd are obtained at frequencies from 470 to 770 MHz  相似文献   
140.
Functions of genes regulating the development of Drosophila peripheral nervous systems are summarized herein. These genes can be classified into 6 groups: <1> prepattern genes, <2> proneural genes, <3> neurogenic genes, <4> neuronal precursor genes, <5> neuronal precursor type selector genes, and <6> cell-division and lineage genes. The mechanisms described herein provide excellent paradigms in the regulation of the development of other tissues in Drosophila, as well as in other organisms, including vertebrates. The roles of two different inhibitory mechanisms, i.e. Notch-signaling and Argos, in the development of Drosophila neural precursor cells are also discussed.  相似文献   
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