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1.

Objective

The study objective was to screen patients with acute type A aortic dissection for anatomic feasibility of ascending aortic endovascular treatment with a valve-carrying conduit.

Methods

High-quality computed tomography scans of 167 patients were available for screening. Aortic dimensions were measured using multiplanar reconstruction in the plane perpendicular to the manually corrected aortic center line. The simulated stent-graft 10-mm–long landing zones were measured starting at the sinotubular junction (proximal landing zone) and ending at the brachiocephalic trunk (distal landing zone). Exclusion criterion was an entry within the aortic root or the landing zone.

Results

In 113 patients (68%), the entry was in a coverable zone in the ascending aorta with sufficient proximal and distal landing zone or in more distal aortic segments. In these patients, the median distance between the proximal and distal landing zone was 89.1 (first quartile: 80.0 mm; third quartile: 101.2 mm) and the median diameter difference was 5.0 mm (2.0; 10.1) (12.3 [4.9; 23.0] %). The diameter difference was less than 2 mm in 32 patients (28%), between 6 mm and 10 mm in 20 patients (18%), between 10 mm and 14 mm in 11 patients (10%), and 14 mm or greater in 10 patients (9%).

Conclusions

Two thirds of all patients who present with type A dissections are potential candidates for treatment with endovascular valve–carrying conduits, but most patients would require tapered stent-grafts.  相似文献   
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Notfall + Rettungsmedizin - Der plötzliche Herz-Kreislauf-Stillstand im Sport ist ein seltenes, aber manchmal ein besonders eindrückliches Ereignis, wie man anhand der Krankengeschichte...  相似文献   
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We have investigated the prognostic value of two novel interim 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) parameters in patients undergoing chemoradiation (CRT) for esophageal squamous cell carcinoma (ESCC): one tumor parameter (maximal standardized uptake ratio rSUR) and one normal tissue parameter (change of FDG uptake within irradiated nontumor-affected esophagus SUVNTO). PET data of 134 European and Chinese patients were analyzed. Parameter establishment was based on 36 patients undergoing preoperative CRT plus surgery, validation was performed in 98 patients receiving definitive CRT. Patients received PET imaging prior and during fourth week of CRT. Clinical parameters, baseline PET parameters, and interim PET parameters (rSUR and SUVNTO) were analyzed and compared to event-free survival (EFS), overall survival (OS), loco-regional control (LRC) and freedom from distant metastases (FFDM). Combining rSUR and SUVNTO revealed a strong prognostic impact on EFS, OS, LRC and FFDM in patients undergoing preoperative CRT. In the definitive CRT cohort, univariate analysis with respect to EFS revealed several staging plus both previously established interim PET parameters as significant prognostic factors. Multivariate analyses revealed only rSUR and SUVNTO as independent prognostic factors (p = 0.003, p = 0.008). Combination of these parameters with the cutoff established in preoperative CRT revealed excellent discrimination of patients with a long or short EFS (73% vs. 17% at 2 years, respectively) and significantly discriminated all other endpoints (OS, p < 0.001; LRC, p < 0.001; FFDM, p = 0.02), even in subgroups. Combined use of interim FDG-PET derived parameters SUVNTO and rSUR seems to have predictive potential, allowing to select responders for definitive CRT and omission of surgery.  相似文献   
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We conducted a prospective longitudinal study of fetal size in rural Papua New Guinea (PNG) involving 439 ultrasound-dated singleton pregnancies with no obvious risk factors for growth restriction. Sonographically estimated fetal weights (EFWs; N = 788) and birth weights (N = 376) were included in a second-order polynomial regression model (optimal fit) to generate fetal weight centiles. Means for specific fetal biometric measurements were also estimated. Fetal weight centiles from a healthy PNG cohort were consistently lower than those derived from Caucasian and Congolese populations, which overestimated the proportion of fetuses measuring small for gestational age (SGA; < 10th centile). Tanzanian and global reference centiles (Caucasian weight reference adapted to our PNG cohort) were more similar to those observed in our cohort, but the global reference underestimated SGA. Individual biometric measurements did not differ significantly from other cohorts. In rural PNG, a locally derived nomogram may be most appropriate for detection of SGA fetuses.  相似文献   
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In this study, the influence of the glass-forming ability (GFA) of a drug on its physical stability in a supersaturated solid dispersion was investigated. Nine drugs were classified according to their GFA using their respective critical cooling rate. Their respective solubility in poly(vinylpyrrolidone-co-vinyl acetate) 6:4 (PVPVA64) was predicted using the melting point depression method based on the Flory-Huggins lattice theory. Supersaturated amorphous solid dispersions at a level of 25% w/w drug above saturation solubility in the polymer were prepared by film-casting, and their respective physical stability at temperatures of 10°C or 20°C above or below their respective Tg (dry conditions) was monitored by the use of polarized light microscopy. This study showed that drugs with good GFA (class 3) on average have higher physical stability in supersaturated amorphous solid dispersion compared to drug with modest GFA (class 2), which in turn have higher physical stability in supersaturated amorphous solid dispersion than drugs with poor GFA (class 1). These results indicate that the GFA of a drug and its physical stability in a supersaturated amorphous solid dispersion stored at a temperature above or below its Tg are correlated.  相似文献   
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Several research teams have focused on finding the “ideal” animal model that reflects the pathophysiological changes and closely simulates the metabolic characteristics of patients with type 2 diabetes. However, the multitude of studies on this topic has resulted in large variations, making the models difficult to compare, as the measured parameters vary significantly. Additionally, selecting the appropriate animal model for a new study has become more difficult due to the increasing number of background variables. This article gives a detailed overview of the literature, covering the entire range of animal models and model characteristics, and most importantly, provides guidance for selecting the most suitable model for specific research goals in the future.  相似文献   
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