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101.
102.
Tarantino U Capone A Planta M D'Arienzo M Letizia Mauro G Impagliazzo A Formica A Pallotta F Patella V Spinarelli A Pazzaglia U Zarattini G Roselli M Montanari G Sessa G Privitera M Verdoia C Corradini C Feola M Padolino A Saturnino L Scialdoni A Rao C Iolascon G Brandi ML Piscitelli P 《Arthritis research & therapy》2010,12(6):R226-9
Introduction
We aimed to assess the incidence and hospitalization rate of hip and "minor" fragility fractures in the Italian population.Methods
We carried out a 3-year survey at 10 major Italian emergency departments to evaluate the hospitalization rate of hip, forearm, humeral, ankle, and vertebral fragility fractures in people 45 years or older between 2004 and 2006, both men and women. These data were compared with those recorded in the national hospitalizations database (SDO) to assess the overall incidence of fragility fractures occurring at hip and other sites, including also those events not resulting in hospital admissions.Results
We observed 29,017 fractures across 3 years, with hospitalization rates of 93.0% for hip fractures, 36.3% for humeral fractures, 31.3% for ankle fractures, 22.6% for forearm/wrist fractures, and 27.6% for clinical vertebral fractures. According to the analyses performed with the Italian hospitalization database in year 2006, we estimated an annual incidence of 87,000 hip, 48,000 humeral, 36,000 ankle, 85,000 wrist, and 155,000 vertebral fragility fractures in people aged 45 years or older (thus resulting in almost 410,000 new fractures per year). Clinical vertebral fractures were recorded in 47,000 events per year.Conclusions
The burden of fragility fractures in the Italian population is very high and calls for effective preventive strategies. 相似文献103.
Ralston SH Uitterlinden AG Brandi ML Balcells S Langdahl BL Lips P Lorenc R Obermayer-Pietsch B Scollen S Bustamante M Husted LB Carey AH Diez-Perez A Dunning AM Falchetti A Karczmarewicz E Kruk M van Leeuwen JP van Meurs JB Mangion J McGuigan FE Mellibovsky L del Monte F Pols HA Reeve J Reid DM Renner W Rivadeneira F van Schoor NM Sherlock RE Ioannidis JP;GENOMOS Investigators 《PLoS medicine》2006,3(4):e90
104.
Development of a magnetic capture hybridization-PCR assay for Listeria monocytogenes direct detection in milk samples 总被引:1,自引:0,他引:1
Amagliani G Omiccioli E Campo A Bruce IJ Brandi G Magnani M 《Journal of applied microbiology》2006,100(2):375-383
AIMS: A rapid and sensitive method for Listeria monocytogenes direct detection from milk was developed. It is based on a magnetic capture hybridization procedure for selective DNA purification, followed by PCR identification. A comparison with two similar commercial systems from Dynal (Dynabeads) was carried out. METHODS AND RESULTS: The technique used previously developed nanoparticles modified with a 21-mer oligonucleotide. This sequence, sharing homology with all the L. monocytogenes strains, was selected on hlyA gene and located outside the desired specific PCR site to avoid cross-contaminations. Capture probe properties, in term of spacer length and purification, were determined to obtain the highest hybridization efficiency. Its specificity was tested in hybridization experiments with nontarget bacterial species. Any inhibitory effect of the nanoparticles on PCR was also examined. The amplification performed with the purified DNA could reliably identify a 10 CFU ml(-1) contamination rate. CONCLUSIONS: The optimized purification method showed a high specificity and sensitivity, with a detection level one log more sensitive than PCR carried out with nucleic acids obtained using commercial nanoparticles. SIGNIFICANCE AND IMPACT OF THE STUDY: The method, avoiding pre-enrichment, provides a rapid alternative to conventional microbiological detection methods. Furthermore, it is suitable for automation and can be proposed for the screening of a large number of samples. 相似文献
105.
Estrogen synthesis in human colon cancer epithelial cells 总被引:7,自引:0,他引:7
Fiorelli G Picariello L Martineti V Tonelli F Brandi ML 《The Journal of steroid biochemistry and molecular biology》1999,71(5-6):223-230
Epidemiological and experimental data suggest an involvement of estrogen in the development and progression of colorectal cancer. In order to determine whether local synthesis of estrogen occurred in human colonic cancer cells, two colorectal cancer cell lines, HCT8 and HCT116, were evaluated for gene expression and enzyme activity of cytochrome P450 aromatase. In addition, the effect on aromatase expression of charcoal-stripped fetal calf serum, of quercetin and genistein and of tamoxifen and raloxifene was investigated in both cell lines. RT-PCR analysis revealed that colorectal adenocarcinoma cell lines contain aromatase as a major component. The conversion of [3H]-androstenedione to estrone and labeled water was dose-dependently inhibited by 4-hydroxyandrostenedione and obeyed Michaelis–Menten kinetic with apparent Km values of 20 nM and Vmax values of approx. 200 and 500 fmol/mg protein/h for HCT8 and HCT116 cells, respectively. After 24 h incubation, genistein (1 μM) significantly increased aromatase activity in HCT8 cells, with no effect on HCT116 cells. In accord with previous observation in reproductive tissues, quercetin (1 μM) significantly inhibited the enzyme activity in both cell lines. Also tamoxifen (100 nM) acted as inhibitor, while raloxifene (10 nM) decreased the enzyme activity only in HCT116 cells. The aromatase gene expression modulation by these effective agents was consistent with their effects on enzyme activity. These findings demonstrate for the first time that colorectal adenocarcinoma cell lines express aromatase. Interestingly, the enzyme activity was inhibited by quercetin, one major dietary flavonoid, by tamoxifen, a hormonal therapeutic agent for breast cancer, and by raloxifene, used in the prevention of postmenopausal osteoporosis. 相似文献
106.
UDP-glucose dehydrogenase (UGDH) catalyzes two oxidations of UDP-glucose to yield UDP-glucuronic acid. Pathological overproduction of extracellular matrix components may be linked to the availability of UDP-glucuronic acid; therefore UGDH is an intriguing therapeutic target. Specific inhibition of human UGDH requires detailed knowledge of its catalytic mechanism, which has not been characterized. In this report, we have cloned, expressed, and affinity-purified the human enzyme and determined its steady state kinetic parameters. The human enzyme is active as a hexamer with values for Km and Vmax that agree well with those reported for a bovine homolog. We used crystal coordinates for Streptococcus pyogenes UGDH in complex with NAD+ cofactor and UDP-glucose substrate to generate a model of the enzyme active site. Based on this model, we selected Cys-276 and Lys-279 as likely catalytic residues and converted them to serine and alanine, respectively. Enzymatic activity of C276S and K279A point mutants was not measurable under normal assay conditions. Rate constants measured over several hours demonstrated that K279A continued to turn over, although 250-fold more slowly than wild type enzyme. C276S, however, performed only a single round of oxidation, indicating that it is essential for the second oxidation. This result is consistent with the postulated role of Cys-276 as a catalytic residue and supports its position in the reaction mechanism for the human enzyme. Lys-279 is likely to have a role in positioning active site residues and in maintaining the hexameric quaternary structure. 相似文献
107.
In this study, we compare cross-sectional growth in two Nilotic pastoralist populations, the Turkana and Karimojong of northern East Africa. Until the middle of the 18th century, these two groups constituted one population, and their genetic affinities consequently are assumed to be strong. Known differences in their subsistence practices as well as their recent cultural history allow us to consider the genetic vs. environmental determinants of their growth patterns. Growth in stature of the two groups is remarkably similar, whereas the pattern of ponderal growth varies, particularly in infancy and adolescence. Both groups demonstrate the linear adult physique that is characteristic of savanna-dwelling peoples in East Africa, but the Karimojong are heavier and fatter after early childhood. Linearity of physique is related to narrow skeletal breadth, a trait that emerges early in childhood among the Karimojong and is strongly correlated with weight: this finding supports the climatic hypothesis of human body shape and size. Extreme leanness, determined from body mass index, is correlated with fat stores, which are only weakly correlated with weight, height, or skeletal breadth. Linearity of physique appears to have a substantial genetic component, whereas fatness is hypothesized to relate to differences in subsistence strategies and exposure to environmental and cultural stress. 相似文献
108.
We investigated the hypothesis that species differences in paternal care in birds may result from differences in concentrations of circulating testosterone (T) and prolactin (PRL). Concentrations of plasma T and PRL were compared in breeding Blue-headed Vireos (Vireo solitarius) and Red-eyed Vireos (Vireo olivaceus), passerine congeners with biparental and maternal incubation, respectively. In male Blue-headed Vireos, plasma T remained low from prenesting to fledgling stages; whereas in male Red-eyed Vireos, plasma T was highest during prenesting and progressively decreased during incubation, nestling, and fledgling stages. In male Blue-headed Vireos, plasma PRL was similar to that in female Blue-headed Vireos and was higher than in male Red-eyed Vireos at all breeding stages. Plasma PRL increased in male Red-eyed Vireos at the incubation stage and remained moderately elevated through the nestling and fledgling stages. In male Blue-headed Vireos, the combination of high PRL and low T during the prenesting stage may promote brood patch formation and nest building, and, at later stages, incubation and feeding of young. In male Red-eyed Vireos, high PRL and low T during incubation and nestling stages may facilitate the feeding of young, as seen in males of other species. Our observations support the hypothesis that differences in paternal care reflect differences in circulating T and PRL. 相似文献
109.
Bactericidal effect of chlorine on motile Aeromonas spp. in drinking water supplies and influence of temperature on disinfection efficacy 总被引:1,自引:0,他引:1
The susceptibility of toxigenic Aeromonas spp. to free chlorine in drinking water supplies, and the influence of environmental temperature on the bactericidal activity of the oxidant, were evaluated. The results showed inactivation curves characterized by an initial phase of rapid reduction of viable cells followed by a slow inactivation of bacteria. The effect of the chlorine compound was markedly influenced by water temperature. At a summer water temperature (20 °C), the efficacy of the chlorine concentrations tested was found to be two to three times lower compared to that found at a winter temperature (5 °C). Resistance was moderately, but significantly, greater in Aer. hydrophila vs Aer. caviae and Aer. sobria , but all Aeromonas spp. were more susceptible than Escherichia coli . Selective pressure with free chlorine did not produce Aeromonas cells with higher levels of chlorine resistance. 相似文献
110.
Conclusion Taken together, these results show the usefulness of the perifusion technique both in the studyof hormone regulation and in the physiopathology of the human pituitary. It allows the studyof dynamic changes in hormone release, relationships between in vivo and in vitro responses, relationships between hormone response and receptor status. Furthermore, we could use this approach to demonstrate release of pituitary neuropeptides and the relation between secretoryprofiles of neuropeptides and those of pituitary hormones. It is another approach to all thesedifferent points than long term culture that needs enzymatic dispersion, and several days ofrecovery before any experiment can be performed on the cells. 相似文献