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41.
Objectives Pacific Islanders are disproportionately burdened by poorer perinatal health outcomes with higher rates of pre-term births, low birth weight babies, infant mortality, and inadequate or no prenatal care. The aim of this study is to examine Marshallese mothers’ beliefs, perceptions, and experiences of prenatal care and to identify potential barriers. Methods Three focus groups were conducted with Marshallese mothers, who were 18 years or older, and living in Arkansas. Focus groups focused on mothers’ beliefs, perceptions, and experiences of prenatal care. A thematic qualitative analysis was conducted to identify salient themes within the data. Results The results demonstrated that negotiating health insurance, transportation, and language barriers were all major structural barriers that constrain prenatal care. The social–cultural barriers that emerged included a lack of understanding of the importance of seeking early and consistent prenatal care, as well as how to navigate the healthcare process. The more complicated challenges that emerged were the feelings of shame and embarrassment due to the perception of their age or being unmarried during pregnancy not being acceptable in American culture. Furthermore, the participants described perceived discrimination from prenatal care providers. Lastly, the participants described fear as a barrier to seeking out prenatal care. Conclusions for Practice This study identified both structural and socio-cultural barriers that can be incorporated into suggestions for policy makers to aid in alleviating maternal health disparities among Pacific Islander women. Further research is needed to address the Marshallese mothers’ perceived discrimination from maternal health care providers.  相似文献   
42.
Previous studies have shown that in vitro exposure to single compounds released from composite resins may induce cell death. In the present study the effects of eluates from commercially available composite resins used for direct or indirect restorations were evaluated on the cell cycle progression and type of cell death of cultured WEHI 13 var fibroblasts. Cells exposed to eluates of the materials were assessed for cytotoxicity by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay for cell death, for cell cycle profiles by flow cytometry, for caspase-3 biochemically and by immunocytochemistry, and for morphological changes by fluorescence microscopy with acridine orange. The direct composite resin eluates induced extensive apoptosis, followed by secondary necrosis. This was accompanied by cell enlargement, micromultinucleation, chromatin disintegration, cell cycle arrest at different phases, and caspase-3 activation. The composites for indirect restorations were much less cytotoxic at all biological end-points investigated. The findings suggest that composite resins used for direct and indirect dental restorations differ in their cytotoxic potential and their ability to affect basic cellular functions. This underlines the impact of improved polymerization with respect to their biologic behavior.  相似文献   
43.
Nurses strive to provide the best quality of care to their patients in a stressful and constantly changing environment. Critical thinking (CT) could help nurses provide better quality of care to their patients. However, studies have shown that nurses either have low levels of CT or underutilize it during clinical practice. A possible explanation could be that nurses experience barriers during the development and/or utilization of CT. Since CT can be cultivated during university, nurse educators could utilize methods that improve CT. However, nurse educators do not sufficiently develop the CT of their students, since they usually rely on teacher-centered methods and not active learning methods. On the other hand, during clinical practice nurses cope with several barriers that inhibit their ability to use CT, such as: lack of teamwork, high levels of stress, time constraints, and understaffing. All these barriers decrease the utilization of CT and the quality of care that nurses provide. The present commentary suggests a simple strategy that could be used by educators and assist graduate nurses overcome the barriers to utilize CT during clinical practice. This strategy consists of three distinct components, namely: individual, interdisciplinary, and administrative. Each component could be used individually to improve the CT of nurses depending on the available resources and facilities. Nevertheless, educators by improving the CT of nurses could assist them in providing better quality of care.  相似文献   
44.
Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2, broke out in December 2019 in Wuhan city of China and spread rapidly worldwide. Therefore, by March 2020, the World Health Organization declared the disease a global pandemic. Apart from the respiratory system, various other organs of the human body are also seriously affected by the virus. Liver injury in patients with a severe form of COVID-19 is estimated to be 14.8%-53.0%. Elevated levels of total bilirubin, aspartate aminotransferase and alanine aminotransferase and low levels of serum albumin and prealbumin are the main laboratory findings. Patients with pre-existing chronic liver disease and cirrhosis are much more prone to develop severe liver injury. This literature review presented the recent scientific findings regarding the pathophysiological mechanisms responsible for liver injury in critically ill patients with COVID-19, the various interactions between drugs used to treat the disease and the function of the liver and the specific tests providing the possibility of early diagnosis of severe liver injury in these patients. Moreover, it highlighted the burden that COVID-19 put on health systems worldwide and its effect on transplant programs and the care provided to critically ill patients in general and particularly to those with chronic liver disease.  相似文献   
45.
In the current study, polymer-based composites, consisting of Acrylonitrile Butadiene Styrene (ABS) and Bismuth Antimony Telluride (BixSb2−xTe3), were produced using mechanical mixing and hot pressing. These composites were investigated regarding their electrical resistivity and Seebeck coefficient, with respect to Bi doping and BixSb2-xTe3 loading into the composite. Experimental results showed that their thermoelectric performance is comparable—or even superior, in some cases—to reported thermoelectric polymer composites that have been produced using other complex techniques. Consequently, mechanically mixed polymer-based thermoelectric materials could be an efficient method for low-cost and large-scale production of polymer composites for potential thermoelectric applications.  相似文献   
46.
47.
Sodium-glucose co-transporter 2 (SGLT2) inhibitors inhibit glucose re-absorption in the proximal renal tubules. Two trials have shown significant reductions of cardiovascular (CV) events with empagliflozin and canagliflozin, which could not be attributed solely to their antidiabetic effects. The aim of the review is the critical presentation of suggested mechanisms/hypotheses for the SGLT2 inhibitors' cardioprotection. The search of the literature revealed many possible cardioprotective mechanisms, because SGLT2 inhibitors (i) increase natriuresis and act as diuretics with unique properties leading to a reduction in preload and myocardial stretch (the diuretic hypothesis); (ii) decrease blood pressure and afterload (the blood pressure lowering hypothesis), (iii) favor the production of ketones, which can act as a ‘superfuel’ in the cardiac and renal tissue (the ‘thrifty substrate’ hypothesis), (iv) improve many metabolic variables (the metabolic effects hypothesis), (v) exert many anti-inflammatory effects (the anti-inflammatory effects hypothesis), (vi) can act through the angiotensin II type II receptors in the context of simultaneous renin-angiotensin-aldosterone-system (RAAS) blockade leading to vasodilation and positive inotropic effects (the RAAS hypothesis), (vii) directly decrease the activity of the upregulated in heart failure Na+–H+ exchanger in myocardial cells leading to restoration of mitochondrial calcium handling in cardiomyocytes (the sodium hypothesis). Additionally, some SGLT2 inhibitors exhibit also SGLT1 inhibitory action possibly resulting in an attenuation of oxidative stress in ischemic myocardium (the SGLT1 inhibition hypothesis). Thus, many mechanisms have been suggested (and possibly act cumulatively) for the cardioprotective effects of SGLT2 inhibitors.  相似文献   
48.
49.
Background and objectives: The pathogenesis and the optimal treatment of eosinophilic pleural effusions are unknown. We aimed to examine whether pneumothorax‐associated pleural eosinophilia in mice is dependent on tumour necrosis factor (TNF)‐alpha, and whether it is affected by systemic administration of corticosteroids. Methods: Mice were injected intrapleurally with 0.4 mL air to create pneumothoraces. Animals were sacrificed 24 or 48 h later, and pleural lavage (PL) was performed. In the first experiment, comparisons were made between wild‐type and TNF‐α knockout mice with pneumothorax. In the second experiment, wild‐type mice were injected intraperitoneally with different doses of dexamethasone (0, 0.25, 0.5 and 1 mg/kg), 5 min before and 24 h after the induction of pneumothorax. Results: After induction of a pneumothorax, TNF‐α knockout mice had significantly fewer total number of cells (P = 0.004), mononuclear cells (P = 0.01), neutrophils (P = 0.017) and eosinophils (P = 0.002) in their PL compared with wild‐type animals. TNF‐α was detected in the PL of most of the control mice but not in TNF‐α knockouts. Dexamethasone induced a significant, dose‐dependent reduction of PL total cells (P < 0.001), eosinophils (P < 0.001), mononuclear cells (P = 0.007) and lymphocytes (P = 0.04) at 48 h, and significantly reduced the number of PL total cells (P = 0.045) and eosinophils (P = 0.005) at 24 h. Furthermore, dexamethasone prevented eosinophil infiltration of lung and pleural tissue. Conclusion: Pneumothorax‐associated pleural eosinophilia in mice is TNF‐α‐dependent and is significantly attenuated by corticosteroid treatment. In addition, both TNF‐α deficiency and dexamethasone treatment were associated with a significant reduction of other types of inflammatory cells in PL.  相似文献   
50.

Background  

Tissue inhibitors of metalloproteinases (TIMPs) play a key role in tissue degradation and remodeling. Since chronic inflammation is associated with tissue remodeling in inflammatory bowel disease (IBD), we evaluated serum TIMP-1 and TIMP-4 levels in IBD patients, in comparison with healthy controls (HC).  相似文献   
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