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61.
H. pylori is a human pathogen that colonizes the epithelium of the stomach. The host immune response may influence the disease process, where cytokines play important roles in the development of disease. In this study, the concentrations of selected cytokines in the gastric antrum and stomach body mucosa and also in the serum were evaluated. Eighty patients according to their rapid urease test were divided into two groups: H. pylori positive (n=39) and H. pylori-negative (n=41). The concentrations of cytokines in biopsies and serum were determined by ELISA method. The mean TNF-α and IFN-γ levels in the infected group were significantly higher than that of uninfected patients. In contrast, IL-10 level in most patients was undetectable. The mean antral of stomach TNF-α and IFN-γ levels were significantly higher than that of the stomach body. IFN-γ serum level showed positive correlation with antrum and stomach body levels, whereas no correlation was found in TNF-α in different samples. Higher levels of TNF-α and IFN-γ in antral indicate that the colonization of bacteria in the antrum may be higher than stomach body (culture results from two sites support this statement). Increased serum level of IFN-γ indicates the activation of circulating-T cells against infection. Induced H. pylori-related TNF-α is concentrated is gastric mucosa and this pathogen does not cause any significant change in the serum level of this cytokine. Therefore H. pylori by inducing certain inflammatory cytokines but not IL-10 may contribute the process of disease development.  相似文献   
62.

Objective

A systematic characterization of hybrid scaffolds, fabricated based on combinatorial additive manufacturing technique and freeze-drying method, is presented as a new platform for osteoblastic differentiation of dental pulp cells (DPCs).

Methods

The scaffolds were consisted of a collagenous matrix embedded in a 3D-printed beta-tricalcium phosphate (β-TCP) as the mineral phase. The developed construct design was intended to achieve mechanical robustness owing to 3D-printed β-TCP scaffold, and biologically active 3D cell culture matrix pertaining to the Collagen extracellular matrix. The β-TCP precursor formulations were investigated for their flow-ability at various temperatures, which optimized for fabrication of 3D printed scaffolds with interconnected porosity. The hybrid constructs were characterized by 3D laser scanning microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, and compressive strength testing.

Results

The in vitro characterization of scaffolds revealed that the hybrid β-TCP/Collagen constructs offer superior DPCs proliferation and alkaline phosphatase (ALP) activity compared to the 3D-printed β-TCP scaffold over three weeks. Moreover, it was found that the incorporation of TCP into the Collagen matrix improves the ALP activity.

Significance

The presented results converge to suggest the developed 3D-printed β-TCP/Collagen hybrid constructs as a new platform for osteoblastic differentiation of DPCs for craniomaxillofacial bone regeneration.  相似文献   
63.
Constrictive pericarditis and anemia post myocardial infarction   总被引:1,自引:0,他引:1  
A 67-year-old male presented with acute inferolateral myocardial infarction complicated by transient acute post infarction pericarditis. Six weeks later, he developed Dressler's syndrome associated with moderately severe anemia of chronic disease. Both of these resolved over the next few weeks, however, shortly thereafter, right sided congestive heart failure occurred. This progressed despite medical therapy and the diagnosis of constrictive pericarditis was made 10 months post infarction. Total pericardectomy was done one year after the onset of acute myocardial infarction with complete resolution of signs and symptoms.  相似文献   
64.
Autoimmune hemolytic anemia (AIHA) is caused by the production of autoantibodies against RBCs. COVID-19 vaccines can reduce the risk of severe disease, however, various adverse effects such as AIHA were observed following vaccination. This review aimed to assess the relationship of AIHA and COVID-19 vaccination using the PRISMA guidelines. Among 18 cases included in this review, new post-vaccination AIHA development was reported in 11 patients (7 women and 4 men) with a median age of 67.0 years. In 7 of 11 and 3 of 11 cases, the onset of symptoms occurred after first and second vaccine dose with median times of 7 and 14 days, respectively. In 1 of 11 cases, the AIHA occurred on Day 17 after booster vaccination. Ten of 11 and 1 of 11 AIHA patients received mRNA- and vector-based vaccine, respectively. After vaccination, 9 of 11, 1 of 11, and 1 of 11 AIHA patients developed warm IgG, cold IgM, and mixed autoantibodies against RBCs, respectively. Significant AIHA exacerbation was reported in seven patients (four women and three men) with a median age of 73.0 years. In 4 of 7 and 2 of 7 exacerbated AIHA cases, the onset of symptoms occurred after first and second vaccine dose with median times of 7 and 3 days, respectively. In 1 of 7 exacerbated AIHA cases, the onset of symptoms was observed on Day 2 after booster vaccination. All exacerbated AIHA cases received mRNA-based vaccines; 3 of 7 and 4 of 7 exacerbated AIHA cases developed IgG and IgM against RBCs, respectively. This review provides a comprehensive explanation regarding the AIHA development and exacerbation after COVID-19 vaccination.  相似文献   
65.

Objective

The epidemiology of hospitalizations with infections among patients with rheumatoid arthritis (RA) is unknown, despite an increase in RA treatments that confer a risk of infection.

Methods

We examined National Inpatient Sample data from 1993–2013. We identified hospitalizations among adults with RA, defined by International Classification of Diseases, Ninth Revision, Clinical Modification codes (714.xx) in any secondary diagnosis field. We evaluated 5 infections as the primary diagnosis: pneumonia, sepsis, urinary tract infection (UTI), skin and soft tissue infections (SSTIs), and opportunistic infections (OIs). The primary outcome was the proportion of hospitalizations for each infection among all hospitalizations with a secondary diagnosis of RA.

Results

There were 792,921 hospitalizations for infection with a secondary diagnosis of RA, with the rates increasing from 90 to 206 per 100,000 persons from 1993–2013. The proportion of hospitalizations decreased for pneumonia (from 5.4% to 4.6%), UTI (from 0.4% to 0.38%), and OIs (from 0.44% to 0.26%). The proportion of hospitalizations for SSTIs increased slightly (from 2.3% to 2.5%), while hospitalizations for sepsis more than tripled (from 1.9% to 6.4%).

Conclusion

Between 1993 and 2013, the proportion of hospitalizations for infections among RA patients appeared to decline for pneumonia and OIs, with a slight decrease in UTI, a slight increase in SSTIs, and a substantial increase in hospitalizations with sepsis. Our results are consistent with previous reports that the sensitivity of sepsis coding has increased over time.
  相似文献   
66.
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68.
We postulated that ventilatory assistance during exercise would improve cardiopulmonary function, relieve exertional symptoms, and increase exercise endurance (T(lim)) in patients with chronic congestive heart failure (CHF). After baseline pulmonary function tests, 12 stable patients with advanced CHF (ejection fraction, 24 +/- 3% [mean +/- SEM]) performed constant-load exercise tests at approximately 60% of their predicted maximal oxygen consumption (V O(2)max) while breathing each of control (1 cm H(2)O), continuous positive airway pressure optimized to the maximal tolerable level (CPAP = 4.8 +/- 0.2 cm H(2)O) or inspiratory pressure support (PS = 4.8 +/- 0.2 cm H(2)O), in randomized order. Measurements during exercise included cardioventilatory responses, esophageal pressure (Pes), and Borg ratings of dyspnea and leg discomfort (LD). At a standardized time near end-exercise, PS and CPAP reduced the work of breathing per minute by 39 +/- 8 and 25 +/- 4%, respectively (p < 0. 01). In response to PS: T(lim) increased by 2.8 +/- 0.8 min or 43 +/- 14% (p < 0.01); slopes of LD-time, V O(2)-time, V CO(2)-time, and tidal Pes-time decreased by 24 +/- 10, 20 +/- 11, 28 +/- 8, and 44 +/- 9%, respectively (p < 0.05); dyspnea and other cardioventilatory parameters did not change. CPAP did not significantly alter measured exercise responses. The increase in T(lim) was explained primarily by the decrease in LD- time slopes (r = -0.71, p < 0.001) which, in turn, correlated with the reductions in V O(2)-time (r = 0.61, p < 0.01) and tidal Pes-time (r = 0.52, p < 0.01). in conclusion, ventilatory muscle unloading with PS reduced exertional leg discomfort and increased exercise endurance in patients with stable advanced CHF.  相似文献   
69.
A rodent behavior analysis system is presented, capable of automated tracking, pose estimation, and recognition of nine behaviors in freely moving animals. The system tracks three key points on the rodent body (nose, center of body, and base of tail) to estimate its pose and head rotation angle in real time. A support vector machine (SVM)-based model, including label optimization steps, is trained to classify on a frame-by-frame basis: resting, walking, bending, grooming, sniffing, rearing supported, rearing unsupported, micro-movements, and “other” behaviors. Compared to conventional red-green-blue (RGB) camera-based methods, the proposed system operates on 3D depth images provided by the Kinect infrared (IR) camera, enabling stable performance regardless of lighting conditions and animal color contrast with the background. This is particularly beneficial for monitoring nocturnal animals’ behavior. 3D features are designed to be extracted directly from the depth stream and combined with contour-based 2D features to further improve recognition accuracies. The system is validated on three freely behaving rats for 168 min in total. The behavior recognition model achieved a cross-validation accuracy of 86.8% on the rat used for training and accuracies of 82.1 and 83% on the other two “testing” rats. The automated head angle estimation aided by behavior recognition resulted in 0.76 correlation with human expert annotation.
Graphical abstract Top view of a rat freely behaving in a standard homecage, captured by Kinect-v2 sensors. The depth image is used for constructing a 3D topography of the animal for pose estimation, behavior recognition, and head angle calculation. Results of the processed data are displayed on the user interface in various forms.
  相似文献   
70.
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