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101.
BACKGROUND: Current total sulfur amino acid (TSAA) requirements of children are based on a factorial estimate that involves several assumptions. OBJECTIVE: The objective was to determine the TSAA requirement (methionine alone) of healthy school-age children by measuring the appearance of 13CO2 (F13CO2) in breath after the oxidation of l-[1-13C]phenylalanine in response to graded methionine intakes. DESIGN: Six healthy school-age children randomly received each of 6 methionine intakes (0, 5, 10, 15, 25, and 35 mg.kg(-1).d(-1)) along with an amino acid mixture to give a final protein intake of 1.5 g.kg(-1).d(-1) and an energy intake of 1.7 x resting energy expenditure. The diet was devoid of cysteine. The mean TSAA requirement was determined by applying a biphase linear regression crossover analysis on F13CO2 data, which identified a breakpoint at minimal F13CO2 in response to graded methionine intakes. RESULTS: The mean and population-safe (upper 95% CI) intakes of TSAA (as methionine) were determined to be 12.9 and 17.2 mg.kg(-1).d(-1), respectively. CONCLUSIONS: The current study suggests that children of this age group have a mean TSAA requirement similar to that of adults (12.6 mg.kg(-1).d(-1)). Therefore, it is valid to use a factorial approach, which assumes that maintenance requirements in childhood are similar to adult requirements, to estimate TSAA requirements in school-age children.  相似文献   
102.
Phenylalanine and serine are amino acids used in dietary supplements and nutritional products consumed by healthy consumers; however, the safe level of phenylalanine or serine supplementation is unknown. The objective of this study was to conduct two 4-week clinical trials to evaluate the safety and tolerability of graded dosages of oral phenylalanine and oral serine. Healthy male adults (n = 60, 38.2 ± 1.8y) completed graded dosages of either phenylalanine or serine supplement (3, 6, 9 and 12 g/d) for 4 weeks with 2-week wash-out periods in between. Primary outcomes included vitals, a broad spectrum of circulating biochemical analytes, body weight, sleep quality and mental self-assessment. At low dosages, minor changes in serum electrolytes and plasma non-essential amino acids glutamine and aspartic acid concentrations were observed. Serine increased its plasma concentrations at high supplemental dosages (9 and 12 g/day), and phenylalanine increased plasma tyrosine concentrations at 12 g/day, but those changes were not considered toxicologically relevant. No other changes in measured parameters were observed, and study subjects tolerated 4-week-long oral supplementation of phenylalanine or serine without treatment-related adverse events. A clinical, no-observed-adverse-effect-level (NOAEL) of phenylalanine and serine supplementation in healthy adult males was determined to be 12 g/day.  相似文献   
103.
104.
Background and Aim: Reactive oxygen species produced by cytochrome P4502E1 (CYP2E1) are believed to play a role in pathophysiology of non‐alcoholic fatty liver disease (NAFLD). However, little is known about the expression, protein content and activity of anti‐oxidant enzymes and the role of inducible nitric oxide synthase (iNOS), a source of reactive nitrogen species, in NAFLD. In the present study, we evaluate gene expression, protein content and activity of anti‐oxidant enzymes, and iNOS, in a CYP2E1 overexpressing model of non‐alcoholic fatty liver (NAFL). Methods: Non‐transgenic (nTg) and CYP2E1 transgenic (Tg) mice were fed rodent chow for 8 months. Alanine aminotransferase (ALT), aspartate aminotransferase (AST), liver triglycerides, malondialdehyde and protein carbonyls were measured. Gene expression of NF‐E2‐related factor (Nrf2), superoxide dismutase‐1, ‐2 (SOD‐1,2), catalase (CAT), glutathione peroxidase (GPx), heme oxygenase‐1 (HO‐1) and iNOS were determined. Protein content, activity and nitrosylation of the enzymes were also measured. Results: Tg mice had greater CYP2E1 activity and histological liver injury. MDA and protein carbonyls were increased, indicating insufficient anti‐oxidant response. Gene expression of Nrf2, CAT, GPx, HO‐1 and iNOS were significantly increased. Protein content and enzyme activities of most anti‐oxidant enzymes were not correspondingly increased. iNOS activity and nitrosylation of CAT and SOD was greater in Tg mice liver. Conclusion: Hepatocyte‐specific CYP2E1 overexpression results in increased oxidative stress and nitrosative stress. Several anti‐oxidant enzymes are upregulated. Failure of corresponding increase in total protein and activity of anti‐oxidant enzymes suggests modification/degradation, possibly by nitrosylation, due to increased iNOS activity in a CYP2E1 overexpressing NAFL mouse model.  相似文献   
105.
Objective: Flupirtine is a non-opioid analgesic without antipyretic or antiphlogistic properties but with favorable tolerability in humans. "Ibis analgesic also exhibits neuroprotective activities. Furthermore, flupirtine antagonizes glutamate- and . , 2+ NMDA-mduced mtracellular levels of Ca and counteracts the effects of focal cerebral Lscherma. Although fluplrtme has been used to relieve pain caused by different diseases and clinical procedures, information on the safety and efficacy of flupirtine is limited. "fhe present study was conducted to investigate the neuroprotective effects of flupirtine on U373 malignant glioma (MG) cell lines. Methods: Cellviability and cell cycle analysis was performed by MTF assay and flow cytomet-,'y, respectively. Results: Variations in the growth of U373 MG cells in $ mM N-methyl-D-aspartate (NMDA), 1 mM flupirtine, and combined treatment indicated the antagonistic effects of NMDA and flupirtine on MG cell lines. The variation in the percentage of gated cellpopulation in different cell cycle phases showed significant variations after 48 h of treatment. Conclusion: Flupirtine has neuroprotective effect of on U373 MG cells, which limits its use in the pain management of brain tumors. This property warrants further studies using animal models and large-scale clinical trials.  相似文献   
106.
Green nanoparticle synthesis has been achieved using environmentally acceptable plant extract and eco-friendly reducing and capping agents. The present study was based on assessments of the antiparasitic activities to determine the efficacies of synthesized silver nanoparticles (AgNPs) using aqueous leaf extract of Mimosa pudica Gaertn (Mimosaceae) against the larvae of malaria vector, Anopheles subpictus Grassi, filariasis vector Culex quinquefasciatus Say (Diptera: Culicidae), and Rhipicephalus (Boophilus) microplus Canestrini (Acari: Ixodidae). Parasite larvae were exposed to varying concentrations of aqueous extract of M. pudica and synthesized AgNPs for 24 h. AgNPs were rapidly synthesized using the leaf extract of M. pudica and the formation of nanoparticles was observed within 6 h. The results recorded from UV–vis spectrum, Fourier transform infrared, X-ray diffraction, scanning electron microscopy, and transmission electron microscopy support the biosynthesis and characterization of AgNPs. The maximum efficacy was observed in synthesized AgNPs against the larvae of A. subpictus, C. quinquefasciatus, and R. microplus (LC50 = 13.90, 11.73, and 8.98 mg/L, r 2 = 0.411, 0.286, and 0.479), respectively. This is the first report on antiparasitic activity of the plant extract and synthesized AgNPs.  相似文献   
107.
The head lice, Pediculus humanus capitis De Geer is an obligate ectoparasite of humans that causes pediculosis capitis, a nuisance for millions of people worldwide, with high prevalence in children. P. humanus capitis has been treated by methods that include the physical remotion of lice, various domestic treatments, and conventional insecticides. None of these methods render complete protection, and there is clear evidence for the evolution of resistance and cross-resistance to conventional insecticides. Non-toxic alternative options are hence needed for head lice treatment and/or prevention, and natural products from plants are good candidates for safer control agents that may provide good anti-lice activity. The plant extracts are good and safe alternatives due to their low toxicity to mammals and easy biodegradability. The present study carried out the pediculocidal activity using the hexane flower bud extract of Syzygium aromaticum (Myrtaceae) against P. humanus capitis examined by direct contact and fumigant toxicity (closed- and open-container methods) bioassay. The chemical composition of S. aromaticum flower bud hexane extract was analyzed by gas chromatography-mass spectrometry. The major chemical constituent (58.79%) of flower bud hexane extract S. aromaticum was identified as chavibetol (5-allyl-2-methoxyphenol) by comparison of mass spectral data and retention times. The hexane extract of S. aromaticum was subjected to gas chromatography analysis, and totally 47 compounds were detected, of which chavibetol was predominantly present. The other major constituents present in the hexane extract were eugenol acetate (phenol,2-methoxy-4-(2-propenyl)-,acetate (15.09%), caryophyllene-(I1) (2,6,10,10-tetramethyl bicyclo [7.2.0] undeca-1,6-diene (13.75%), caryophyllene oxide (3.04%), 2,6,6,9-tetramethyl-1,4,8-cycloundecatriene (1.67%), and copaene (1.33%). The filter paper contact bioassay study showed pronounced pediculicidal activity in the flower bud hexane extract of S. aromaticum. The toxic effect was determined for every five in an 80-min treatment. The result showed percent mortality of 40, 82, and 100 at 5, 10, and 20 min, and the median lethal time (LT(50)) value was 5.83 (0.5 mg/cm(2)); 28, 82, and 100 at 5, 10, and 30 min. (LT(50)?= 6.54; 0.25 mg/cm(2)); and 13, 22, 42, 80, and 100 at 5, 10, 20, 40, and 80 min (LT(50)?= 18.68; 0.125 mg/cm(2)), respectively. The vapor phase toxicity was tested at 0.25 mg/cm(2). There was a significant difference in pediculicidal activity of S. aromaticum extract against P. humanus capitis between closed- and open-container methods. Adult mortalities were determined for every five in 60 min (closed method) and for every ten in 180 min (open method). The closed method showed the percent mortality was 45, 88, and 100 at 5, 10, and 15 min (LT(50)?= 5.39), respectively. In the open-container method, the percent mortality was observed 5, 20, 47, 84, and 100 at 10, 20, 60, 120, and 180 min (LT(50)?= 47.91), respectively. The mortality was more effective in the closed containers than in open ones, indicating that the effect of hexane extract was largely a result of action in the vapor phase exhibited fumigant toxicity. Studies of anti-lice activity of extract provide the basis for preliminary conclusions of structure activity relationships; although no clear patterns can yet be drawn. We here attempt to provide a concise compilation of the available information on anti-lice activity of plant extracts and plant-derived compounds.  相似文献   
108.
The aim of this study was to investigate the larvicidal potential of the hexane, chloroform, ethyl acetate, acetone, methanol, and aqueous leaf extracts of Nelumbo nucifera Gaertn. (Nymphaeaceae) and synthesized silver nanoparticles using aqueous leaf extract against fourth instar larvae of Anopheles subpictus Grassi and Culex quinquefasciatus Say (Diptera: Culicidae). Nanoparticles are being used in many commercial applications. It was found that aqueous silver ions can be reduced by aqueous extract of plant parts to generate extremely stable silver nanoparticles in water. The results recorded from UV–vis spectrum, scanning electron microscopy, X-ray diffraction, and Fourier transform infrared support the biosynthesis and characterization of silver nanoparticles. Larvae were exposed to varying concentrations of plant extracts and synthesized silver nanoparticles for 24 h. All extracts showed moderate larvicidal effects; however, the maximum efficacy was observed in crude methanol, aqueous, and synthesized silver nanoparticles against the larvae of A. subpictus (LC50 = 8.89, 11.82, and 0.69 ppm; LC90 = 28.65, 36.06, and 2.15 ppm) and against the larvae of C. quinquefasciatus (LC50 = 9.51, 13.65, and 1.10 ppm; LC90 = 28.13, 35.83, and 3.59 ppm), respectively. These results suggest that the leaf methanol, aqueous extracts of N. nucifera, and green synthesis of silver nanoparticles have the potential to be used as an ideal eco-friendly approach for the control of the A. subpictus and C. quinquefasciatus. This is the first report on the mosquito larvicidal activity of the plant extracts and synthesized nanoparticles.  相似文献   
109.
Behçet's disease is a multisystem inflammatory disorder of unknown etiology. We report a 12-year-old boy who presented with features of raised intracranial tension and seizures and was found to have cerebral venous sinus thrombosis on evaluation. Behçet's disease was diagnosed based on occurrence of recurrent oral and genital ulcers in the past and characteristic skin lesions subsequently. He also showed significant personality changes including multiple attempts of deliberate self-harm. Pedigree analysis revealed that six family members spanning three generations had recurrent oral ulcers and three members satisfied the criteria for Behçet's disease. Clinical features varied amongst the family members and there was suggestion of genetic anticipation. The index case was carrying HLA-B37/B7 and the mother was carrying B37/B40. Our report sheds light on the genetics of Behçet's disease. Unusual features were early age of onset, cerebral venous sinus thrombosis, significant personality changes and strong family history with phenotypic heterogeneity.  相似文献   
110.
BACKGROUND: The efficacy of analgesia with bilateral infraorbital nerve block and intravenous (i.v.) fentanyl were compared for cleft lip surgery in children. METHODS: Eighty-two children aged 3 months to 10 years undergoing cleft lip repair were prospectively randomized to one of two groups: bilateral infraorbital nerve block (Group B), or i.v. fentanyl (Group F). Group B (n = 41) received bilateral infraorbital injection of 1 ml 0.25% bupivacaine and 2 ml i.v. saline as control. Group F (n = 41) received 2 microg x kg(-1) i.v. fentanyl, and bilateral infraorbital injection of 1 ml saline as control. Pain was evaluated by the incidence of tachycardia, hypertension, and/or modified pain score > or =4. The time to awakening, time to first cry and time to feeding were noted. RESULTS: Thirty four children (82.9%) in Group B had adequate analgesia compared with 15 (36.6%) in Group F (P < 0.0001, RR of failure 0.27 for Group B). Group B had a mean time to awakening of 5.65 +/- 2.52 min (Group F: 9.37 +/- 4.50 min; P < 0.0001), time to first cry 32.14 +/- 18.22 min (Group F: 28.00 +/- 16.27 min; P = 0.3), time to feed 62.05 +/- 20.06 min (Group F: 72.44 +/- 17.72; P = 0.015), and pain score 2.81 +/- 1.38 (Group F: 4.71 +/- 1.89; P < 0.0001). There were no major complications. CONCLUSIONS: Bilateral infraorbital block is superior to fentanyl in terms of analgesia, and time to awakening and feeding.  相似文献   
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