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A DNA optical sensor system is proposed based on the combination of sandwich solution hybridization, magnetic bead capture, flow injection and chemiluminescence for rapid detection of DNA hybridization. Bacterial alkaline phosphatase (phoA) gene and Hepatitis B virus (HBV) DNA were used as target DNA. A biotinylated DNA probe was used to capture the target gene onto the streptavidin-coated magnetic beads and a calf intestine alkaline phosphatase (CAP)-labelled DNA probe was used for subsequent enzymatic chemiluminescence detection. The detection cycle was less than 30 min, excluding the DNA hybridization time, which was about 100 min. Both the phoA gene and HBV DNA could be detected at picogramme or femtomole level. No response signal was obtained when target DNA did not exist in the sample. Successive sample detection could be made by removing the magnetic field and a washing step.  相似文献   
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Two glycoside-based prodrugs, 125IUdR-5'-beta-D-glucopyranoside and 125IUdR-5'-beta-D-galactopyranoside, were synthesized. This selection was dictated by the abundance of appropriate enzymes in the GI tract of mice and similar levels of beta-D-glycosidases in human and rodent large intestine. Studies to establish the ability of colonic microflora to release 125IUdR were conducted in vitro and in Swiss Webster mice. Both prodrugs released 125IUdR in the presence of the corresponding enzymes or the GI content homogenates in vitro, and in vivo. Luminal enzymes in the proximal and distal small intestine in mice degraded less than 10% of each prodrug whereas enzymes from the colonic/caecal lumen of mice released nearly 100% of 125IUdR. 125IUdR freed by bacterial glycosidases was stable in the GI content. No significant amounts of other metabolites or deiodination products were observed. Total radioactivity recovered as by-products was less than 10%. The efflux of prodrugs from the GI tract after oral administration in mice was slow and limited. Unlike 125IUdR, prodrugs were not dehalogenated in vivo as indicated by biodistribution and imaging studies.  相似文献   
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AIM: To study the anxiogenic effect of naltrexone (Nal) on the emotional state of rats. METHODS: The duration of active interaction was measured in the social interaction test in rats. RESULTS: Without influence on the locomotor activity, Nal (0.1-50 mg.kg-1) dose- and time-dependently decreased the duration of active interaction, which was antagonized by morphine (5 mg.kg-1) or fenclonine (Fen, 150 mg.kg-1 x 3 d) and was enhanced by 5-hydroxytryptophan (5-HTP, 50 mg.kg-1). CONCLUSION: Nal produced anxiety via its blockade of opioid receptors; central opioidergic neurons were involved in the regulation of anxiety through their tonic inhibitions in serotonergic neurons.  相似文献   
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Interactions between endoprostheses made of carbonic composition "Ostec" and bone tissue were studied after plastic repair of experimental vast defects in the mandible in 22 rabbits and 10 dogs over the course of 2 years. Histologic findings showed the formation of a layer of fibrous connective tissue 3 months after the operation and later; at some places the implant directly joins the rabbit bone, which frequently undergoes chondroid transformation. Microscopically, the structure of "Ostec" represents carbonic threads forming large bundles. By the 6th and 12th months of experiment connective tissue elements penetrate the fissures between the bundles and the perforation gaps of the endoprosthesis, forming bone-like and bone structures in them.  相似文献   
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BACKGROUND: "Medial synovial entrapment syndrome of the hip" is a preliminary name given by the authors to describe the topic of this paper. The authors hope to elicit the concern of clinicians and further explore the feasibility of this nomenclature for the described syndrome. METHODS: A total of 26 children with synovial disorder of the hip complained of limited motion and pain of various degrees in the hip, and a limp or refusal to bear weight. Clinical presentation, image studies, course and management were thoroughly reviewed and compared with other well-established synovial disorders of the hip. RESULTS: Twenty-two of the patients were cured by bedrest, skin traction and manipulative reduction. The remaining four patients were treated with surgery and had satisfactory results. Because of its unique clinical manifestation and the good results obtained from manipulative reduction, it is difficult to compare this condition with any other well-established disease entities. Thus, the authors suggest medial synovial entrapment syndrome of the hip (SES) as a preliminary name. CONCLUSIONS: Based on the 26 Chinese children with SES studied, the authors used clinical, anatomic and biomechanical bases for deriving this nomenclature. The similarity between transient synovitis and SES is discussed.  相似文献   
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Many studies have demonstrated the postoperative analgesic efficacy of fentanyl delivered i.v. by patient-controlled analgesia (PCA) devices at demand doses ranging from 10 to 50 microg, but none has sought to define the optimal fentanyl PCA dose. In this randomized, double-blind, multicenter study, we compared the safety and efficacy of three administered demand-dose sizes of fentanyl (20, 40, and 60 microg) in 150 patients after major surgery. Efficacy was dose-dependent; positive response rates (i.e., a global assessment score of "very good" or "excellent" and the absence of severe opioid adverse effects) were 42%, 52%, and 68% for the 20, 40, and 60 microg demand-dose groups, respectively, and were significantly higher in the 60 microg demand-dose group. The number of doses administered and missed attempts were significantly smaller in the 40 and 60 microg demand-dose groups compared with the 20 microg demand-dose group. This suggests that the 20 microg demand dose provided inadequate pain relief. Adverse respiratory events were more frequent and mean respiratory rates were significantly slower with the 60 microg demand dose, compared with the 20 or 40 microg demand doses. These results indicate that, of these three doses, the 40 microg demand dose was optimal for fentanyl PCA management of moderate to severe pain after major surgery. IMPLICATIONS: The postoperative analgesic efficacy of fentanyl delivered i.v. by patient-controlled analgesia devices has been demonstrated for demand doses ranging from 10 to 50 microg, but the optimal fentanyl dose remains unknown. In this randomized, double-blind study, we compared three demand dose sizes of fentanyl (20, 40, and 60 microg) and found that the 40 microg demand dose was the most appropriate for fentanyl patient-controlled analgesia management of postoperative pain.  相似文献   
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The postmortem stature was measured in 57 Korean adult males (age range: 20-86 years old, mean: 52.3 years old) in supine position. After dissection of the corpses, we measured the maximum length of the remaining limb-bones (humerus, radius, ulna, femur, tibia and fibula). The correlation coefficients between the stature and each limb-bone length were calculated. Simple regression equations for estimating stature from each limb-bone length and multiple regression equations from the combination of limb-bone lengths were also obtained.  相似文献   
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