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71.
Background : How tissue patterns form in development and regeneration is a fundamental issue remaining to be fully understood. The integument often forms repetitive units in space (periodic patterning) and time (cyclic renewal), such as feathers and hairs. Integument patterns are visible and experimentally manipulatable, helping us reveal pattern formative processes. Variability is seen in regional phenotypic specificities and temporal cycling at different physiological stages. Results: Here we show some cellular/molecular bases revealed by analyzing integument patterns. (1) Localized cellular activity (proliferation, rearrangement, apoptosis, differentiation) transforms prototypic organ primordia into specific shapes. Combinatorial positioning of different localized activity zones generates diverse and complex organ forms. (2) Competitive equilibrium between activators and inhibitors regulates stem cells through cyclic quiescence and activation. Conclusions: Dynamic interactions between stem cells and their adjacent niche regulate regenerative behavior, modulated by multi‐layers of macro‐environmental factors (dermis, body hormone status, and external environment). Genomics studies may reveal how positional information of localized cellular activity is stored. In vivo skin imaging and lineage tracing unveils new insights into stem cell plasticity. Principles of self‐assembly obtained from the integumentary organ model can be applied to help restore damaged patterns during regenerative wound healing and for tissue engineering to rebuild tissues. Developmental Dynamics 244:905–920, 2015. © 2015 Wiley Periodicals, Inc.  相似文献   
72.
l-Menthol is the main ingredient of peppermint which affects various pharmacological effects such as anti-inflammation and anti-oxidative activity. In this study, we aimed to evaluate the potential effects of l-menthol on cigarette smoke extract (CSE) induced lung injury in rats. Morphology assessment results revealed that administration with l-menthol (5, 10 or 20 mg kg−1 d−1) significantly alleviated CSE-induced lung injury. Besides, l-menthol significantly reduced the inflammatory response by suppressing the production of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β) and interleukin-6 (IL-6) via downregulating nuclear factor kappa B (NF-κB) and p38 MAPK pathways. Meanwhile, l-menthol decreased the levels of oxidative stress markers including malondialdehyde (MDA) and myeloperoxidase (MPO) whereas it increased the amount of glutathione (GSH), glutathione peroxidase (GSH-Px), superoxide dismutase (SOD) and total antioxidant capacity (T-AOC) through activation of the Nrf2 pathway. Furthermore, the expression of MMP-9 and TIMP-1 in lungs was reduced after treatment with l-menthol, and this indicated that l-menthol might have a potential effect on airway remodeling. Moreover, immunohistochemistry analyses indicated that l-menthol could suppress the infiltration of CD4+ and CD8+ T cells in lung tissues and this was probably due to the immune regulation activity of l-menthol. Taken together, our findings support that l-menthol might be a potential candidate for the treatment of CSE-induced lung injury in rats.

l-Menthol is the main ingredient of peppermint which affects various pharmacological effects such as anti-inflammation and anti-oxidative activity.  相似文献   
73.
Monodisperse colloidal particles have promising applications in electrophoretic displays with vivid colors, reversibility and low switching times. In this study, a facile, effective and large-scale strategy for preparing size-controlled Fe3O4@SiO2 particles is reported. Multiple Fe3O4 particles were synthesized by a modified solvothermal method using sodium citrate as a surface modifier with a binary solvent, and were then coated with a SiO2 layer to obtain a highly negatively charged surface via a modified Stöber method. Owing to the easily controlled sizes and sufficient surface charges, Fe3O4@SiO2 particles can be assembled into colloidal amorphous arrays with the balance of electrostatic repulsion and electrophoretic forces. The reflections cover wavelengths ranging from 802 to 453 nm, and were optimized by investigating the dependence of the particles on variables such as particle size, particle volume fraction, and electric field intensity. The large-scale preparation of electrically responsive Fe3O4@SiO2 particles facilitates an electrophoretic display with broad-range colors, showing the practical potential in industrial application.

Fe3O4@SiO2 particles were prepared on the gram-scale by selecting Na3Cit as the modifier with binary solvent and were assembled into colloidal amorphous arrays with unique and attractive optical properties for EPD.  相似文献   
74.

Background

The Activity Measure for Post-Acute Care was developed to evaluate the limitations of activities of adult individuals with different health conditions.

Objectives

To translate and cultural adapt the Activity Measure for Post-Acute Care short forms for outpatients into Portuguese–Brazilian, to verify the comprehension of the items and categories of the responses by users of the rehabilitation services and to analyze the reliability indices of the instrument.

Methods

Translation and back-translation were conducted by two independent teams. Cognitive interviews (n = 2) evaluated the comprehension of the translated version among patients. Item reliability and consistency was also investigated.

Results

There was conceptual equivalence between the translated and original versions. For some items, the information was modified in order to attend to the measurement units used in Brazil. Comparative analyses of the translated versions chose the most appropriate term to capture the English content. The few discrepancies identified in the back-translation were solved by consensus. The cognitive interviews detected few comprehension problems, which were solved by means of repetition of the item statement and use of examples to clarify the specificity of the information. The final translated short forms of the instrument showed excellent test-retest reliability and inter-examiner reliability indices, as well as high internal consistency.

Conclusion

The Portuguese version of the Activity Measure for Post-Acute Care short forms will provide Brazilian clinicians and researchers with an up-to-date instrument for the evaluation of functioning of adults with various clinical conditions who attend outpatient rehabilitation settings.  相似文献   
75.

Background

S and s antigens of the MNS system are of clinical importance because alloanti-S and -s have usually caused delayed hemolytic transfusion reactions and hemolytic disease of the fetus and newborn. Various red cell genotyping has been established to predict the phenotypes to solve serological test limitations.

Objectives and methods

This study aimed to determine S and s genotype frequencies and to estimate the alloimmunization risks among central, northern and southern Thai populations. Altogether, 1237 blood samples from Thai blood donors were included. Only 150 samples were tested with anti-S and anti-s by indirect antiglobulin test. All samples were genotyped for GYPB*S and GYPB*s alleles using inhouse PCR with sequence-specific primer. Additionally, the allele frequencies were used to estimate alloimmunization risks and compare with other populations.

Results

The phenotyping and genotyping results in 150 samples were in 100% concordance. The allele frequencies of GYPB*S in central, northern and southern Thais were 0.061, 0.040 and 0.097, and GYPB*s were 0.939, 0.960 and 0.903, respectively. The frequencies among central Thais were similar to those among northern Thai and Korean populations (P?>?0.05) but significantly differed from those of Asian, Caucasian African American and Hispanic populations (P?<?0.05). In addition, the risk of S alloimmunization among southern Thais (0.1566) was higher than those among central (0.1038) and northern Thais (0.0736).

Conclusion

This was the first study to report S and s predicted phenotypes and estimate alloimmunization risks among Thais, which is beneficial to prevent transfusion-induced alloimmunization among donors and patients.  相似文献   
76.
77.

Objectives

This prospective, observational study evaluated changes in ultrasound measurements of the inferior vena caval index (IVCI), the aorta diameter/IVC diameter index (Ao/IVCD), and the aorta area/IVC area index (Ao/IVCA) during fluid administration in children requiring intravenous fluid administration.

Methods

Children who presented to the pediatric emergency department with symptoms of dehydration were enrolled between May 2015 and February 2016. The maximum diameter of the aorta, from inner wall to inner wall, and the long and short axis diameters of IVC were measured using a convex array transducer in the transverse view. Subsequently, we measured the diameter of the IVC at the subxiphoid area during inspiration and expiration in longitudinal view. We calculated IVCI, Ao/IVCD, and Ao/IVCA during administration of 10 ml/kg and 20 ml/kg normal saline boluses.

Results

IVCI and Ao/IVCA significantly changed immediately after administration of initial 10 ml/kg of NS. Ao/IVCA showed significant change during the additional administration of 10 ml/kg (total 20 ml/kg) normal saline boluses (1.43, IQR 1.12–1.86 vs. 1.08, IQR 0.87–1.45, p value < 0.001). No significant changes were observed for IVCI and Ao/IVCD. Ao/IVCA was significantly correlated with the volume of fluid administered. The coefficient between initial and administration of the 10 ml/kg normal saline bolus was ? 0.396 (p value = 0.010), and that between the 10 ml/kg and 20 ml/kg normal saline boluses was ? 0.316 (p value = 0.038).

Conclusions

Ao/IVCA showed better correlations with the volume of fluid administered than IVCI and Ao/IVCA. Ao/IVCA might be a promising index for assessing the effects of fluid administration.  相似文献   
78.
Clinical Rheumatology - Articular cartilage and periarticular muscle tissues are strongly affected during knee osteoarthritis (OA). Creatine kinase (CK) is an enzyme expressed in several tissues,...  相似文献   
79.
Clinical Rheumatology - Thrombotic microangiopathy (TMA) in systemic lupus erythematosus is a rare manifestation associated with activation of the complement system. This study aimed to compare...  相似文献   
80.
Journal of Thrombosis and Thrombolysis - Patients with COVID-19 are known to be at risk of developing both venous, arterial and microvascular thrombosis, due to an excessive immuno-thrombogenic...  相似文献   
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