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81.
Clinical Oral Investigations - To answer the questions: (1) Does reducing estrogen levels influence the microbial composition of the oral cavity? (2) Does the presence of periapical lesion (PL)...  相似文献   
82.
There are a variety of techniques for treating chronically discharging radical mastoid cavities. The purpose of this article is to report the preliminary results of an original technique for reconstruction of the posterior auditory canal using a titanium net combined with porous hydroxyapatite coating. Titanium is fixed with two screws to the mastoid tip and zygomatic root to prevent the risk of implant dislocation. Eight patients with chronically discharging radical mastoid cavities that failed medical management underwent reconstruction of the mastoid cavity using this technique. After surgery, all cases had rapid healing and good aeration of the middle ear and mastoid. One tympanic membrane reperforated, and no extrusion of the prostheses were detected clinically or on computed tomography scanning. The minimum postoperative follow-up period has been 12 months (range 12-48 months). To date, there has been no evidence of cholesteatoma recurrence. The preliminary results remain encouraging. Larger series and longer follow-up, however, are advisable to prove real validity.  相似文献   
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To prospectively investigate morphologic and functional changes after intravitreal bevacizumab for persistent diffuse and clinically significant diabetic macular edema. In total, 26 eyes in 26 patients were treated with three intravitreal injections of bevacizumab (Avastin?) given at 4-week intervals. Study parameters included: visual acuity (VA), perceived visual improvement, central macular thickness as measured by Spectralis OCT, macular sensitivity and fixation pattern as measured by MP-1 microperimetry, and the incidence of ocular and systemic side-effects. At the time of follow-up, 76.9 % of eyes showed a significant improvement in VA (p = 0.012), 38.4 % showed a one-line improvement on the ETDRS chart compared with VA at day 0, 30.7 % showed a two-line improvement, and 7.6 % showed at least a three-line improvement. The mean central macular thickness was 447 microns at day 0 and 311.1 microns at follow-up (p = 0.003). The mean baseline macular sensitivity, by MP-1 microperimetry, was 8.29 dB; at follow -up, macular sensitivity had improved to 14.26 dB (p = 0.025). These results support further controlled trials on the efficacy of intravitreal bevacizumab in treating diabetic macular edema. Microperimetry and OCT are important tools in managing diabetic patients, providing a detailed study of the macular region, particularly when it is necessary to monitor the morphological and functional outcome after various interventions. A good correlation between retinal sensitivity and perceived visual performance was found.  相似文献   
84.
Samples of Mytilus galloprovincialis were harvested from five different locations in Thermaikos gulf, Greece after harmful algae bloom. All of the mussel samples were found positive by mouse bioassay for diarrhetic shellfish poisoning (DSP) toxins. Liquid chromatography (LC) coupled with mass spectrometry (MS) was used to search for the following lipophilic toxins: okadaic acid (OA), dinophysistoxins (DTXs), pectenotoxins (PTXs), azaspiracids (AZAs) and yessotoxins (YTXs). In order to investigate the presence of okadaic acid esters, alkaline hydrolysis was performed for all the samples, and LC-MS analyses were carried out on the samples before and after hydrolysis. Hydrophilic interaction liquid chromatography-mass spectrometry (HILIC-MS) analyses were also carried out to investigate the presence of domoic acid and paralytic shellfish poisoning (PSP) toxins at trace levels. All of the samples were found to be contaminated only with okadaic acid at levels 0.10-0.20 microg/g.  相似文献   
85.
The state of the art of LC-MS of palytoxin and its analogues is reported in the present review. MS data for palytoxin, 42-hydroxy-palytoxin, ostreocin-D, mascarenotoxins, and ovatoxins, obtained using different ionization techniques, namely fast-atom bombardment (FAB), matrix assisted laser desorption ionization (MALDI), and electrospray ionization (ESI), are summarized together with the LC-MS methods used for their detection. Application of the developed LC-MS methods to both plankton and seafood analysis is also reported, paying attention to the extraction procedures used and to limits of detection (LOD) and quantitation (LOQ) achieved. In a research setting, LC-MS has shown a good potential in determination of palytoxin and its analogues from various sources, but, in a regulatory setting, routine LC-MS analysis of palytoxins is still at a preliminary stage. The LOQ currently achieved in seafood analysis appears insufficient to detect palytoxins in shellfish extract at levels close to the tolerance limit for palytoxins (30 μg/kg) proposed by the European Food Safety Authority (EFSA, 2009). In addition, lacking of certified reference standard of palytoxins as well as of validation studies for the proposed LC-MS methods represent important issues that should be faced for future perspectives of LC-MS technique.  相似文献   
86.
The structure alerts (SA) for carcinogenicity/mutagenicity are a repository of the science on chemical biological interactions; in addition, they have a crucial role in practical applications for risk assessment. In predictive toxicology, it is crucial that knowledge of SAs is accompanied by knowledge of the structural motifs that modulate their effects. Recently, we have compiled an updated list of SAs implemented in the expert system Toxtree 1.50 (open source, freely available). These SAs are aimed at discriminating between active and inactive chemicals, and include only modulating factors with a high probability of eliminating completely the effect of the SA. Here we have examined the factors that modulate carcinogenic potency: this is an additional piece of information that can have a role in fine‐tuning a risk assessment. The case study selected is the carcinogenic potential of the aromatic amines in rats and mice. As the carcinogenic potency of these compounds is different in mice and rats (correlation coefficient = 0.546), there are both agreements and differences in the pattern of these motifs. Differences are observed mainly for the motifs that decrease the carcinogenic potency of aromatic amines. In mice, substitutions ortho and meta to the amino group tend to decrease the potency, as well as ?NO2 in any position. In rats, these motifs affect the potency to a more limited extent. On the other hand, increasing effects are quite similar in the two animals and are exerted mainly by additional rings, tricyclic systems, five‐numbered rings, and N‐heteroaromatic systems. Environ. Mol. Mutagen. 2009. © 2009 Wiley‐Liss, Inc.  相似文献   
87.
The diarrhetic shellfish toxin composition in the digestive glands of mussels from the northern Adriatic sea was investigated. Along with known yessotoxins, identified by comparison of their chromatographic and spectral properties with those reported in the literature, we isolated a new analogue of yessotoxin, 42,43,44,45,46,47,55-heptanor-41-oxohomoyessotoxin, 1. Its structure was determined by (1)H NMR spectroscopy and mass spectrometry.  相似文献   
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Nephropathology is an integral component of nephrology education. Online teaching sites provide valuable educational materials to learners, but learner satisfaction has not been measured. We developed a nephropathology website and measured learners' satisfaction. The Nephrology On-Demand Histopathology website (http://blog.ecu.edu/sites/nephrologyondemand/?page_id=4502) provided nephropathologic specimens with explanations. Users were asked to complete a Likert-based survey (1-strongly agree . . . 5-strongly disagree) regarding four key areas of content quality: accuracy, currency, objectivity, and usefulness. Learners of all training levels perceived the content quality favorably. The mean (±SD) for accuracy was 1.70 (0.89), currency 1.62 (0.90), objectivity 1.80 (1.01), and usefulness 1.72 (0.95). Nephrology On-Demand Histopathology is a well-received teaching tool to learners of all training levels. Educators may consider using it, as well as other online nephropathology sites, as adjunctive teaching tools.  相似文献   
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