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21.
BACKGROUND: Mediastinal masses represent a diagnostic challenge because of their proximity to numerous critical structures, difficulty of access for tissue sampling, and myriad potential pathologic etiologies. A large, single-center experience with EUS-guided fine-needle aspiration (EUS-FNA) in the diagnosis of non-lung cancer-related mediastinal masses is presented. METHODS: An EUS database was reviewed and all cases of mediastinal mass or lymphadenopathy encountered between 1994 and 1999 were included. Final diagnoses were determined by EUS-FNA cytology and clinical follow-up. RESULTS: Forty-nine patients were identified (27 women, 22 men; mean age 58.1 years, range 30-89 years). A malignant process was diagnosed in 22 cases (45%) and a benign process in 24 (49%). The EUS-FNA specimen was nondiagnostic in 3 cases (6%). An accurate diagnosis was made in 46 of the 49 patients (94%). No complication was noted. CONCLUSIONS: EUS-FNA is a minimally invasive technique that facilitates detection and tissue sampling of mediastinal masses. It is a safe procedure that can be performed with the patient under conscious sedation in an outpatient setting.  相似文献   
22.

Background

Tranexamic acid (TXA) has been successfully used to reduce bleeding in joint replacement. Recently local TXA has been advocated to reduce blood loss in total knee or hip replacement; however, this raised concerns about potential adverse effects of TXA upon the artificial joint replacement.

Materials and methods

In this biomechanical study we compared the effects of TXA and saline upon the following biomechanical properties of artificial joint materials—(1) tensile properties (ultimate strength, stiffness and Young’s modulus), (2) the wear rate using a multi-directional pin-on-plate machine, and (3) the surface topography of pins and plates before and after wear rate testing.

Results

There were no significant differences in tensile strength, wear rates or surface topography of either ultra-high-molecular-weight polyethylene pins or cobalt chromium molybdenum metal plates between specimens soaked in TXA and specimens soaked in saline.

Conclusion

Biomechanical testing shows that there are no biomechanical adverse affects on the properties of common artificial joint materials from using topical TXA.

Level of evidence

V  相似文献   
23.
Parkin and the glial cell line–derived neurotrophic factor (GDNF) receptor RET have both been independently linked to the dopaminergic neuron degeneration that underlies Parkinson’s disease (PD). In the present study, we demonstrate that there is genetic crosstalk between parkin and the receptor tyrosine kinase RET in two different mouse models of PD. Mice lacking both parkin and RET exhibited accelerated dopaminergic cell and axonal loss compared with parkin-deficient animals, which showed none, and RET-deficient mice, in which we found moderate degeneration. Transgenic expression of parkin protected the dopaminergic systems of aged RET-deficient mice. Downregulation of either parkin or RET in neuronal cells impaired mitochondrial function and morphology. Parkin expression restored mitochondrial function in GDNF/RET-deficient cells, while GDNF stimulation rescued mitochondrial defects in parkin-deficient cells. In both cases, improved mitochondrial function was the result of activation of the prosurvival NF-κB pathway, which was mediated by RET through the phosphoinositide-3-kinase (PI3K) pathway. Taken together, these observations indicate that parkin and the RET signaling cascade converge to control mitochondrial integrity and thereby properly maintain substantia nigra pars compacta dopaminergic neurons and their innervation in the striatum. The demonstration of crosstalk between parkin and RET highlights the interplay in the protein network that is altered in PD and suggests potential therapeutic targets and strategies to treat PD.  相似文献   
24.
Successful renal transplantation across HLA barrier in sensitized individuals has been on the rise during the past decade, primarily due to improved desensitization regimes. The aim of this study was to share outcome of desensitization in renal transplant recipients with donor‐specific anti‐HLA antibodies (DSA). This was a retrospective analysis of all HLA immunized individuals who were prospective renal transplant recipients. All such patients underwent preconditioning as per the institutional desensitization protocol. Complement‐dependent cytoxicity‐based crossmatch (CDC‐XM), luminex‐based crossmatch (LM‐XM) and flowcytometry‐based crossmatch (FC‐XM) were done in all cases. If any of these tests turned out positive, single antigen bead assay (SAB) was performed. Desensitization for DSA was performed in 55 patients and all patients were followed‐up for 1 year to assess graft function and patient outcome. CDC‐XM being a less sensitive assay, could not detect incompatibility in 29 (52.73%) cases. After desensitization, even though SAB and LM‐XM results revealed an MFI within acceptable range, FC‐XM being an extremely sensitive assay, continued to give a positive result in eight (14.55%) cases. The mean ± SD number of pretransplant TPE were 3.44 ± 0.98 (2‐11). Out of 55, there were 10 patients who were lost to follow up. Patient and graft survival of 45 patients at 1 year was found to be 100%. Preconditioning for renal transplants in the form of immunosuppression with TPE is an extremely useful auxiliary for transplantation in HLA sensitized renal transplant recipients.  相似文献   
25.
Emphysema is characterized by loss of lung elasticity and irreversible air space enlargement, usually in the later decades of life. The molecular mechanisms of emphysema remain poorly defined. We identified a role for a novel cathepsin, cathepsin E, in promoting emphysema by inducing mitochondrial fission. Unlike previously reported cysteine cathepsins, which have been implicated in cigarette smoke-induced lung disease, cathepsin E is a nonlysosomal intracellular aspartic protease whose function has been described only in antigen processing. We examined lung tissue sections of persons with chronic obstructive pulmonary disease, a clinical entity that includes emphysematous change. Human chronic obstructive pulmonary disease lungs had markedly increased cathepsin E protein in the lung epithelium. We generated lung epithelial-targeted transgenic cathepsin E mice and found that they develop emphysema. Overexpression of cathepsin E resulted in increased E3 ubiquitin ligase parkin, mitochondrial fission protein dynamin-related protein 1, caspase activation/apoptosis, and ultimately loss of lung parenchyma resembling emphysema. Inhibiting dynamin-related protein 1, using a small molecule inhibitor in vitro or in vivo, inhibited cathepsin E-induced apoptosis and emphysema. To the best of our knowledge, our study is the first to identify links between cathepsin E, mitochondrial fission, and caspase activation/apoptosis in the pathogenesis of pulmonary emphysema. Our data expand the current understanding of molecular mechanisms of emphysema development and may provide new therapeutic targets.Emphysema is a major subset of chronic obstructive pulmonary disease (COPD) and is defined anatomically as the destruction of the distal lung parenchyma and enlargement of the air spaces. Pulmonary emphysema is one of the main causes of morbidity and death worldwide. The most studied factor in developing COPD has long been recognized to be cigarette smoking. However, only 10% to 20% of heavy smokers develop clinically significant COPD.1,2 Importantly, recent studies indicate that complementary pathogenic mechanisms, such as proteolytic/antiproteolytic imbalance, oxidative stress, apoptosis, or altered innate immunity, are involved in the development and progression of alveolar destruction.3–6Cathepsins have been implicated in mediating alveolar destruction via their proteolytic activity. Cathepsins are intracellular hydrolases and include serine proteases (cathepsins A and G), aspartic proteases (cathepsins D and E), and cysteine cathepsins (cathepsins B, C, F, H, K, L, O, S, V, X, and W). Cathepsin E (Cat E), a nonlysosomal intracellular aspartic protease, is homologous to aspartic protease cathepsin D, a major proteolytic activity in the lysosomal component.7 Recent studies have reported that Cat E plays an important role in antigen processing via the major histocompatibility complex class II pathway, host defense against cancer cells and invading microorganisms, gastric differentiation, and development of signet-ring cell carcinoma.8–12 However, Cat E has not been linked to lung disease.Human lung sections from persons with COPD indicated increased expression of Cat E protein in the lung epithelial cells. To investigate if increased expression of lung epithelial Cat E could lead to emphysema, we generated lung-targeted constitutive and inducible Cat E transgenic (Tg) mice. Our data indicated that inducible Cat E Tg mice developed emphysema-like lung changes as early as 1 week. We noted robust caspase 3 activation, and, when mice were administered a caspase inhibitor, emphysema was prevented. To our surprise, we did not find changes in caspases usually associated with caspase 3 activation, such as caspases 8 and 9, in Cat E Tg mice. Instead, we found significant induction of a mitochondrial fission protein, dynamin-related protein 1 (Drp1). When we inhibited Drp1 in Cat E Tg mice with Mdivi-1, a small molecule Drp1 inhibitor, we completely abolished the development of emphysema. Collectively, our data indicate that increased Cat E is a clinically relevant finding in human COPD and invoke a novel role for Cat E in mitochondrial fission-induced emphysema.  相似文献   
26.

Objective

To assess the prevalence of first hour breastfeeding initiation and exclusive breastfeeding at 6 wk and identify its barriers in healthy term babies born in a tertiary hospital setting.

Methods

A prospective observational cohort study was carried out in consecutively selected 400 mothers who delivered (normal, instrumental or cesarean) term healthy babies in a tertiary care hospital setting. All mother-infant dyads were enroled within 48 h of delivery.

Results

Breastfeeding was initiated within first hour in 255 out of 400, i.e., 64 % of babies. Cesarean delivery and male gender were strongest risk factors for delayed initiation of breastfeeding [OR (95 % CI)?=?1.99 (1.14–3.48) and 34.17 (17.10–70.40) respectively]. Among the babies followed up till 6–8 wk, 83 % were exclusively breastfed. Breast milk substitutes were given in 172/400 (43 %) babies on day one, which emerged as an independent predictor of failure to continue exclusive breastfeeding at 6 wk (OR 2.96; 95 % CI 1.09–8.06). Odds of exclusive breastfeeding were two times higher in babies breastfed within first hour (n?=?255/400, 64 %) when compared to babies initiated breastfeeds beyond first hour (n?=?145/400, 36 %) (OR 2.01;05 % CI 1.12–3.61).

Conclusions

Cesarean section and male gender emerged as significant risk factors for delayed initiation (beyond first hour) of breastfeeding in the index study cohort. In addition, use of breast milk substitute emerged as the only predictor for failure to continue exclusive breastfeeding at six weeks in a tertiary care hospital.  相似文献   
27.
The Neonatal Resuscitation Program (NRP) consists of an algorithm and curriculum to train healthcare professionals to facilitate newborn infants’ transition to extrauterine life and to provide a standardized approach to the care of infants who require more invasive support and resuscitation. This review discusses the most recent update of the NRP algorithm and recommended guidelines for the care of newly born infants. Current challenges in training and assessment as well as the importance of ergonomics in the optimization of human performance are discussed. Finally, it is recommended that in order to ensure high-performing resuscitation teams, members should be selected and retained based on objective performance criteria and frequent participation in realistic simulated clinical scenarios.  相似文献   
28.
Gallbladder(GB) wall thickening is a frequent finding caused by a spectrum of conditions. It is observed in many extracholecystic as well as intrinsic GB conditions. GB wall thickening can either be diffuse or focal. Diffuse wall thickening is a secondary occurrence in both extrinsic and intrinsic pathologies of GB, whereas, focal wall thickening is mostly associated with intrinsic GB pathologies. In the absence of specific clinical features, accurate etiological diagnosis can be challenging. The survival rate in GB carcinoma(GBC) can be improved if it is diagnosed at an early stage, especially when the tumor is confined to the wall. The pattern of wall thickening in GBC is often confused with benign diseases, especially chronic cholecystitis, xanthogranulomatous cholecystitis, and adenomyomatosis. Early recognition and differentiation of these conditions can improve the prognosis. In this minireview, the authors describe the patterns of abnormalities on various imaging modalities(conventional as well as advanced) for the diagnosis of GB wall thickening. This paper also illustrates an algorithmic approach for the etiological diagnosis of GB wall thickening and suggests a formatted reporting for GB wall abnormalities.  相似文献   
29.
30.
Aim: The aim of this study was to assess the effect of different orthodontic treatment needs on the OHQoL of adolescents. Materials and methods: 200 subjects (100 males and 100 females), 11 to 15 years of age were recruited for the study. OHQoL was assessed with the short form of the oral health impact profile (OHIP-14), and malocclusion severity was assessed with the index of orthodontic treatment need (IOTN). The Chi-square test was used to analyse the qualitative data. The level of significance was 0.05. Results: The more severe the malocclusion the worse was the impact on the OHQoL. Orthodontic treatment need had almost similar impact on the daily activities of both males and females. Pronunciation and taste was not significantly affected by the need for orthodontic treatment in either males or females. The proportions of orthodontic patients who found it uncomfortable to eat any food and had to interrupt their meals were significantly correlated with orthodontic treatment needs in both males and females. Conclusion: Orthodontic treatment need had an impact on OHQoL of adolescents with no significant difference between males and females. Clinical significance: Orthodontists should be aware of the impact caused by malocclusion and orthodontic treatment on the quality of life of the patients and should provide regular positive reinforcements to them. Keywords: Oral health-related qualtiy of life, Orthodontic treatment need, Malocclusion. How to cite this article: Manjith CM, Karnam SK, Manglam S, Praveen MN, Mathur A. Oral Health-Related Quality of Life (OHQoL) among Adolescents Seeking Orthodontic Treatment. J Contemp Dent Pract 2012;13(3):294-298. Source of support: Nil Conflict of interest: None declared.  相似文献   
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