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Background

Increasing antimicrobial resistance among the key pathogens responsible for community-acquired respiratory tract infections has the potential to limit the effectiveness of antibiotics available to treat these infections. Since there are regional differences in the susceptibility patterns observed and treatment is frequently empirical, the selection of antibiotic therapy may be challenging. PROTEKT, a global, longitudinal multicentre surveillance study, tracks the activity of telithromycin and comparator antibacterial agents against key respiratory tract pathogens.

Methods

In this analysis, we examine the prevalence of antibacterial resistance in 1,336 bacterial pathogens, isolated from adult and paediatric patients clinically diagnosed with acute bacterial sinusitis (ABS).

Results and discussion

In total, 58.0%, 66.1%, and 55.8% of S. pneumoniae isolates were susceptible to penicillin, cefuroxime, and clarithromycin respectively. Combined macrolide resistance and reduced susceptibility to penicillin was present in 200/640 (31.3 %) of S. pneumoniae isolates (128 isolates were resistant to penicillin [MIC >= 2 mg/L], 72 intermediate [MIC 0.12–1 mg/L]) while 99.5% and 95.5% of isolates were susceptible to telithromycin and amoxicillin-clavulanate, respectively. In total, 88.2%, 87.5%, 99.4%, 100%, and 100% of H. influenzae isolates were susceptible to ampicillin, clarithromycin, cefuroxime, telithromycin, and amoxicillin-clavulanate, respectively. In vitro, telithromycin demonstrated the highest activity against M. catarrhalis (MIC50 = 0.06 mg/L, MIC90 = 0.12 mg/L).

Conclusion

The high in vitro activity of against pathogens commonly isolated in ABS, together with a once daily dosing regimen and clinical efficacy with 5-day course of therapy, suggest that telithromycin may play a role in the empiric treatment of ABS.  相似文献   
195.
The objective of the present study was to evaluate a comprehensive set of urinary biomarkers for oxidative damage to lipids, proteins and DNA, in man. Eighteen moderately trained males (mean age 24.6+/-0.7) exercised 60min at 70% of maximal O2 uptake on a cycle ergometer. Urine fractions for 12 h were collected 1 day before, and for 3 consecutive days after exercise. As biomarkers of lipid peroxidation, 8 aldehydes (i.e. propanal, butanal, pentanal, hexanal, heptanal, octanal, nonanal and malondialdehyde-MDA)and acetone were analyzed in urines by gas chromatography with electron capture detection (GC-ECD). As a biomarker of protein oxidation, o,o'-dityrosine was analyzed in urine samples by a recently developed isotope dilution HPLC-atmospheric pressure chemical ionization (APCI)-tandem-mass spectrometry (HPLC-APCI-MS/MS) methodology. As a biomarker of oxidative DNA damage, urinary excretion of 8-hydroxy-2'-deoxyguanosine (8-OHdG) was measured by an ELISA method. On the day of exercise, significant increases were observed in urinary excretions of acetone (p < 0.025, n = 18) and butanal (p < 0.01, n = 18) in the 12h daytime fractions compared to the daytime fraction before exercise. The urinary acetone excretion was also significantly (p < 0.05) increased on the 1st day after exercise. Octanal and nonanal were increased in the daytime urine fraction on the 2nd day after exercise. However, these increases were of borderline significance (p = 0.09 and p = 0.07, respectively). Significantly elevated urinary o,o'-dityrosine amounts were observed in the daytime fraction on the day of exercise (p < 0.025) and on the 1st day after exercise (p = 0.07) compared to the before exercise daytime fraction. Excretion of urinary 8-OHdG was statistically significantly increased in the daytime fractions on the day of exercise (p = 0.07) and on the 1st day after exercise (p < 0.025) compared to before exercise daytime fraction. Increases in urinary excretions of acetone, propanal, pentanal, MDA and 8-OHdG significantly correlated with training status (hours of exercise/week) of the volunteers, while o,o'-dityrosine did not. To our knowledge, the present study is the first to evaluate a multi-parameter non-invasive biomarker set for damage to three main cellular targets of ROS. It shows that 1 h of exercise may already induce oxidative damage in moderately trained individuals and that the chosen urinary biomarkers are sensitive enough to monitor such damage.  相似文献   
196.
Biodistribution of phosphodiester and phosphorothioate siRNA   总被引:10,自引:0,他引:10  
Short interfering RNAs (siRNAs) are valuable tools for analyzing protein function in mammalian cell culture. This success has led to high expectations for in vivo and therapeutic applications. However, the pharmacokinetic properties of siRNA are not known. Here we report the biodistribution of a phosphodiester (PO) siRNA duplex and examine the effect of phosphorothioate (PS) linkages. Our findings indicate that biodistribution of siRNA is similar to that for single-stranded antisense oligonucleotides and offer insights for use of siRNA in vivo.  相似文献   
197.
The mononuclear nickel complex NiL (LH2 = N,N'-bis(salicylidene)-1,3-diaminopropane) can be transformed into the tetranuclear complex [NiL(H2O)Pb(SCN)2(DMF)]2 in the aid of SCN-, DMF (dimethylformamide) and Pb(II) ions. The complex was characterized by elemental analysis and FTIR investigation. The crystal structure reveals it is a nonlinear Ni(II)-Pb(II)-Pb(II)i-Ni(II)i (i: 1-x, 1-y, 1-z) heterotetranuclear complex and crystallizes in the triclinic space group P1. The Ni(II) and Pb(II) ions have a distorted octahedral coordination geometry. There are three kinds of mu-bridge in the molecule between the metal ions. Each pair of Ni and Pb ions in the asymmetric unit is equatorially linked by two phenolic oxygen bridging atoms of N,N'-bis(salicylidene)-1,3-propanediaminato (salpd(2-), C17H16N2O2(2-)) ligand. The dinuclear centres from tetranuclear clusters Ni-Pb(i) and Ni(i)-Pb pairs are bridged by two mu-1,3-SCN groups. Pb(II) and Pb(II)i ions are also bridged by the oxygen atoms of DMF molecules. The tetranuclear units are hydrogen bonded by two O-H...N intermolecular interactions along the c-axis. The complex was screened for antibacterial and antifungal activities by the disc diffusion and microtiter plate techniques using DMF as solvent. The minimum inhibitory concentration values were calculated. It has been found that antimicrobial activities of the complexes are higher than the free ligand.  相似文献   
198.
We describe a newborn with multiple congenital anomalies consistent with an oro-facio-digital syndrome (OFDS). These are a group of inherited syndromes that have in common anomalies of the tongue (bifid or lobulated tongue with hamartomas), the face (median cleft lip) and the digits (brachydactyly, polydactyly, clinodactyly and/or syndactyly). OFDS has been classified into 11 types. The case described in this paper had manifestations overlapping with OFDS II (Mohr) and OFDS IV (Mohr-Majewski) and OFDS VI (Varadi). We propose that the present patient has a new variation of the OFDS due to the co-existence of the very atypical combination of polydactyly, cerebellar hypoplasia, hypothalamic hamartoma and classical facial findings of OFDS.  相似文献   
199.
Scalp layers are widely used in reconstructive procedures. The authors used prefabricated galeal flaps based on the superficial temporal or postauricular vessels for ear, cheek, mandible, and cranium reconstructions in three cases. In case 1, synchronous beard and ear reconstructions were accomplished by using the temporoparietal and retroauricular flaps. In case 2, a buccomandibular defect was reconstructed by transposing the supra-auricular and retroauricular galea with prefabricated bone and skin. In case 3, an epidural hematoma in the left frontoparietal area was evacuated after a circular craniectomy. The harvested bone was not put back on the defect area but buried between the periosteal and galeal layers because of brain edema. These layers were raised as an osteogaleoperiosteal flap and transposed onto the defect area after 7 weeks. When used with a prefabrication method, scalp layers offer versatile options for repairing composite defects of the head region. A galeal flap based on the posterior auricular vessels is practical and reliable in reconstructive procedures. The authors suggest that this flap is an option in cases in which the temporoparietal fascia artery or the superficial temporal artery is not available. Prefabrication of the harvested cranial bone inside the adjacent tissues offers several advantages in that a viable bone is provided at the end of the procedure, intervention at a distant area is avoided, the graft is placed on osteogenic tissue (periosteum) that is also transposed onto the defect, and sophisticated procedures such as microsurgical techniques are not needed.  相似文献   
200.
The aim of the study was to investigate the arterial anatomy of the lower lip. The location, course, length, and diameter of the inferior labial artery and the sublabial artery were revealed by bilateral meticulous anatomic dissections in 14 adult male preserved cadaver heads. Another cadaver head was used for silicone rubber injection to fill the regional arterial tree. The inferior labial artery was the main artery of the lower lip and in all cases branched off the facial artery. The mean length of the inferior labial artery was found to be 52.3 mm (range, 16 to 98 mm). The mean distance of the origin of the inferior labial artery from the labial commissura was 23.9 mm. The mean external diameter of the inferior labial artery at the origin was 1.2 mm. The sublabial artery was present in 10 (71 percent) of the cadavers. Mean measurements of this artery were 1 mm for diameter, 23.4 mm for length, and 27.6 mm for distance from the labial commissura. The sublabial artery may originate from the facial artery or the inferior labial artery. This study found that this region does not have a constant arterial distribution, the inferior labial artery and the sublabial artery (if it exists) can be in different locations unilaterally or bilaterally, and the diameter and the length may vary.  相似文献   
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