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1.
The present study aimed to determine whether a whole body vibration training program (WBV) is able to improve static standing balance in adolescents with and without Down syndrome (DS). Thirty adolescents with DS aged 11–20 years (DSG) and 27 adolescent, age/sex matched, without DS (CG) joined the study. Participants of each group were divided into two comparable groups, those who performed WVB (in DSG: VDSG; in CG: VCG) and those who did not perform WVB (in DSG: nVDSG; in CG: nVCG). Static-standing-balance under four conditions (C1: openeyes/fixed-foot-support; C2: closed-eyes/fixed-foot-support; C3: openeyes/compliant-foot-support; C4: closed-eyes/compliant-foot-support) was examine, before and after a 20-week WBV training program. For balance study, Postural-Parameters (PPs), based on center of pressure (COP) oscillations (anterior/posterior and medial/lateral COP excursion and COP mean velocity), and PPs ratios among the four conditions were calculated. After WBV training, no significant differences were found in any parameter in the VCG and nVCG and neither in the nVDSG, but there was a decrease of mean values in the analyzed PPs under C4, with significant differences in medial/lateral COP excursion and COP mean velocity, and a significant decrease in the ratio C4/C1 of the mean velocity in VDSG. Therefore, WBV training had positive effects in the balance of DS adolescents although only under specific conditions, with vision and somatosensory input altered. The positive results of this study are encouraging and open a wide field of research, looking for the most efficient program for this population.  相似文献   
2.
IntroductionMany presbycusic patients have difficulty in understanding certain words. This could be justified because certain sounds in Spanish are more difficult to perceive, particularly the sounds with energy in the high frequencies. We propose to use a sentence as a tool to check this theory.Materials and methodAll the Spanish sounds were analyzed, measuring the degree of acoustic energy in all the frequencies. The conclusions drawn from the comparison of the results allowed the design of the tool that is proposed here.ResultsWe established a gradient of perception difficulty, occlusive consonants being the least perceptible, followed by fricative, and finally all those segments with harmony and a clear formant structure. The Spanish sentence “Ana vio ese coche rojizo fino” is proposed as the tool for this study. This sentence has some as it comprises certain peculiarities that makes it particularly useful for this purpose. It will allow us to check whether understanding deteriorates as we move from beginning to end, helping evaluate the importance of high frequencies for intelligibility.ConclusionsA positive result could help in the design of amplification systems to improve speech intelligibility. In addition, the exploratory tool could allow neuro-acoustic exploration, useful in the central auditory pathology studies.  相似文献   
3.
A series of bis([(9-oxo-9,10-dihydroacridine-4-carbonyl)amino]alkyl) alkylamines have been prepared and their antiproliferative properties have been tested against HT-29 cell lines. Compounds 6b and 6d showed an interesting cytotoxic profile and were subjected to further cytotoxic evaluation, DNA binding properties and molecular modelling studies. The evaluation of the cytotoxic activity of compounds 6b and 6d against pairs of cisplatin-sensitive and -resistant ovarian tumour cells shows that both compounds may be endowed with interesting antitumour properties because they are able to circumvent cisplatin resistance in A2780cisR, CH1cisR and Pam 212-ras tumour cells. On the other hand, DNA binding data indicate that compounds 6b and 6d are able to intercalate stronger than acridine within the double helix. Both compounds displace ethidium bromide with an efficiency ten times higher than acridine from several linear double-stranded DNAs and induce 43 degrees unwinding in supercoiled pBR322 DNA while acridine unwinds pBR322 DNA by only 24 degrees. Altogether these data indicate that the significant conformational changes induced by compounds 6b and 6d in the double helix are due to a bis-intercalative DNA binding mode. We propose that binding to DNA through bisintercalation might be at least in part responsible for the remarkable cytotoxic properties of these acridine derivatives. The complex of 6b with d(GCGCGC)(2) in the four possible orientations that the ligand can adopt when binding to the DNA hexamer have been modelled and subjected to molecular dynamics simulations with the aim of evaluating the binding preferences of this bisintercalating agent into the DNA molecule. The predictions suggest that 6b binds to d(GCGCGC)(2) with a parallel orientation of the chromophores relative to each other and with a preference for binding through the minor groove of the hexamer. The possible relevance of these findings to the process of bisintercalation and the antitumour profile of these compounds is discussed in this paper.  相似文献   
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5.
BACKGROUND: Infant mortality and its neonatal and postneonatal aspects are important health indicators and thus warrant regular analysis even in developed countries where the rates thereof have dropped considerably. This study is aimed at describing the changes recorded in these rates in Andalusia over the past twenty-five years. METHODS: The annual infant, early and late neonatal and postneonatal mortality rates have been calculated for the 1975-1998 period. Poisson regression was used to estimate the annual percentages of change in the rates for the 1975-1986 and 1987-1998 periods, as well as for the entire 1975-1998 period. An analysis was also made of the proportional mortality rate due to infectious, respiratory, congenital causes, disorders having arisen during the perinatal period and all other causes, as well as the ratio for mortality rates due to disorders having arisen in the perinatal period and for all causes as a whole for the 1994-1998 four-year period as compared to the 1975-1979 period, in infant, neonatal (early and late) and postnatal periods. RESULTS: The greatest percentage drops were in early (6.38%) and late (4.6%) neonatal mortality. The ratio for mortality rates due to disorders having arisen in the perinatal period for the 1994-1998 and 1975-1975 periods is 10 for the postneonatal mortality rate, whilst it is under 1 for the late (0.63) and early (0.33) neonatal and infant (0.30) mortality. CONCLUSIONS: Mortality during the infant, early and late neonatal and postneonatal periods dropped sharply during the 1975-1998 period. The risk of death due to disorders arising during the perinatal period among children ranging from four weeks to one year of age (postneonatal period) rose tenfold during the 1975-1979 and 1994-1998 periods.  相似文献   
6.
Cultivated chickpea is the third most important legume after field bean and garden pea worldwide. Despite considerable breeding towards improved yield and resistance to biotic and abiotic stresses, the production of chickpea remained stagnant, but molecular tools are expected to increase the impact of current improvement programs. As a first step towards this goal, various genetic linkage maps have been established and markers linked to resistance genes been identified. However, until now, only one linkage group (LG) has been assigned to a specific chromosome. In the present work, mitotic chromosomes were sorted using flow cytometry and used as template for PCR with primers designed for genomic regions flanking microsatellites. These primers amplify sequence-tagged microsatellite site markers. This approach confirmed the assignment of LG8 to the smallest chromosome H. For the first time, LG5 was linked to the largest chromosome A, LG4 to a medium-sized chromosome E, while LG3 was anchored to the second largest chromosome B. Chromosomes C and D could not be flow-sorted separately and were jointly associated to LG6 and LG7. By the same token, chromosomes F and G were anchored to LG1 and LG2. To establish a set of preferably diagnostic cytogenetic markers, the genomic distribution of various probes was verified using FISH. Moreover, a partial genomic bacterial artificial chromosome (BAC) library was constructed and putative single/low-copy BAC clones were mapped cytogenetically. As a result, two clones were identified localizing specifically to chromosomes E and H, for which no cytogenetic markers were yet available.  相似文献   
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8.
Cisplatin resistance observed in some human tumors has prompted research in platinum derivatives that can circumvent this effect. Despite initial works reporting lack of activity of trans-platinum derivatives, complexes with the general formula PtCl2(L)(L') exhibit cytotoxic activity in cisplatin-sensitive and -resistant cell lines. Here we reported the chemical and biological properties of seven platinum complexes with PPh3 or PMe2Ph in trans to several amines. They show important antitumoral properties in tumor cell lines. Among the compounds, those with a replacement of an ammine ligand in the inactive trans-DDP by a phosphine ligand have an important enhancement of their cytotoxic activity. In SKOV3, no G1 nor G2/M accumulation was observed after treatments, and apoptosis was launched probably by a mechanism independent of classical checkpoints activation. Our data indicate that our compounds are not cross-resistant with cisplatin and might be promising agents in the treatment of tumors unresponsive to cisplatin.  相似文献   
9.
The macrolide resistance determinants and genetic elements carrying the mef(A) and mef(E) subclasses of the mef gene were studied with Streptococcus agalactiae isolated in 2003 and 2004 from 7,084 vaginorectal cultures performed to detect carrier pregnant women. The prevalence of carriage was 18% (1,276 isolates), and that of erythromycin resistance 11.0% (129 of the 1,171 isolates studied). erm(B), erm(A) subclass erm(TR), and the mef gene, either subclass mef(A) or mef(E), were found in 72 (55.8%), 41 (31.8%), and 12 (9.3%) erythromycin-resistant isolates, while 4 isolates had more than 1 erythromycin resistance gene. Of the 13 M-phenotype mef-containing erythromycin-resistant S. agalactiae isolates, 11 had the mef(E) subclass gene alone, one had both the mef(E) and the erm(TR) subclass genes, and one had the mef(A) subclass gene. mef(E) subclass genes were associated with the carrying element mega in 10 of the 12 mef(E)-containing strains, while the single mef(A) subclass gene found was associated with the genetic element Tn1207.3. The nonconjugative nature of the mega element and the clonal diversity of mef(E)-containing strains determined by pulsed-field gel electrophoresis suggest that transformation is the main mechanism through which this resistance gene is acquired.  相似文献   
10.
Platelet pro-aggregatory effects of CD40L monoclonal antibody   总被引:1,自引:0,他引:1  
An unexpected high incidence of thromboembolic complications has been described in patients with systemic autoimmune diseases treated with CD40L immunotherapy. Since activated platelets express CD40L, we aimed to investigate the effects of CD40L mAb in platelet aggregation induced by physiological stimuli. Optical aggregometry was performed on platelet-rich plasma and washed platelets obtained from systemic venous blood (0.38% citrate) of anesthetized pigs. CD40L mAb clone 5c8, used in clinical trials for autoimmune diseases, was used. In platelet-rich plasma, CD40L mAb neither induced platelet aggregation per se, nor significantly affected maximal aggregation or slope of ADP-induced aggregation curves. However, it dose-dependently inhibited spontaneous deaggregation observed in ADP-stimulated samples. This effect was not observed with an irrelevant isotype-matched immunoglobulin. The stabilizing effect on platelet aggregates was neither glycoprotein IIb/IIIa-mediated nor Ca2+-dependent but was abolished by acetylsalicylic acid pretreatment. F(ab')2 fragments did not stabilize ADP-induced platelet aggregates but inhibited the stabilizing effect of CD40L mAb. Similar results were obtained with washed platelets, although higher amplification of ADP-induced aggregation was observed. In conclusion, CD40L expression produced by physiological or pathophysiological platelet activation can sustain a pro-aggregatory effect of CD40L mAb by a mechanism involving mAb Fc domain. These results could help to explain the mechanism of CD40L mAb-induced thromboembolic complications.  相似文献   
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