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41.
Journal of Thrombosis and Thrombolysis - Oral anticoagulants (OACs) are high alert medications and require high-quality management to optimize health outcomes. The objective of this scoping review...  相似文献   
42.

Objectives

A scoring method for tooth erosion is needed to enable community-based assessments. The aim of this study was to evaluate the Basic Erosive Wear Examination (BEWE) scoring method, using data previously collected from two studies.

Materials and methods

In a national survey of erosion in children and adolescents, a representative, 20 % nationwide sample of 2,251 children, aged 6, 12 and 15 years, was examined. Erosion, recorded for all surfaces of permanent teeth, was converted to a BEWE score. For a group of referred patients, erosion was scored for 351 patients and then converted to a BEWE score.

Results

From the national survey, no erosion was seen in permanent teeth of 6 years old, but was present in 12 years old (19.9 % boys, mean BEWE of 0.22; 11.0 % girls, mean BEWE of 0.079; p?<?0.001). Among 15 years old, erosion was seen in 30.7 % of subjects (38.3 % boys, mean BEWE of 1.00; 22.7 % girls, mean BEWE of 0.42; p?<?0.001). For the referred patients, the BEWE score was 9.4 for subjects with gastric reflux symptoms but 6.0 for those without symptoms (p?<?0.001).

Conclusions

The value of scoring with the BEWE methodology was clearly demonstrated, showing increasing severity of erosion between 12 and 15 years and gender differences in erosion severity. Intrinsic acid erosion clearly caused an increased BEWE score.

Clinical relevance

The BEWE scoring methodology appears valuable for assessing erosion in populations.  相似文献   
43.
We reviewed the cytologic features and results of ancillary studies in eight fine-needle aspiration biopsies (FNAB) performed by posterior approach in 8 patients with unresectable Wilms' tumor (WT). Chemotherapy was given following the FNAB diagnosis of WT, which was confirmed subsequently by histologic examination of surgically resected specimens. Indications for FNAB included: unresectable tumor, bilateral disease, initial presentation with metastatic disease, uncertainty regarding tumor site, and documentation of recurrence. Cytologic examination revealed blastemal cells (8/8 aspirates), spindle cells (3/8 aspirates), and epithelial differentiation or tubules (3/8 aspirates). There was no cytologic evidence of anaplasia in any of the cases. Immunocytochemical studies on cell blocks and/or smears showed cytokeratin positivity in 5/8 and vimentin positivity in 5/5 of the aspirates in which these studies were performed. Focal positivity for neuron-specific enolase (NSE) was seen in 3/3 aspirates. Stains for actin and leukocyte-common antigen were negative (0/3 and 0/2 aspirates, respectively). DNA ploidy analysis of the aspiration material by flow cytometry revealed near-diploid populations in three aspirates. Electron microscopic findings helpful for diagnosis included: cell junctions, microvilli, flocculent basement membrane-like material, cilia, autophagolysosomes, and lack of neuroectodermal differentiation. Diagnostic morphologic pitfalls for an incorrect diagnosis of neuroblastoma included nuclear molding (all aspirates), pseudorosette formation (one aspirate), and focal NSE positivity (3/3 aspirates). None of the tumors showed anaplasia on histologic examination. Cytologic recognition of the triphasic cellular components of WT (blastemal cells, spindle cells, and epithelial cells) can be helpful for a correct diagnosis; however, in 5/8 aspirates in this study, only the blastemal component was present. In these cases, immunocytochemical stains and electron microscopy proved useful in arriving at a correct FNAB diagnosis of WT. However, NSE positivity can be a pitfall for a diagnosis of neuroblastoma if the radiologic, clinical, and other cytologic features are not clearly delineated. Presence of cytokeratin and vimentin positivity would be helpful in the diagnosis of WT in such instances. Diagn Cytopathol 1996; 14:101–107. © 1996 Wiley-Liss, Inc.  相似文献   
44.
Tumor cells upregulate myriad proteins that are important for pH regulation, resulting in the acidification of the extracellular tumor microenvironment (TME). Abnormal pH is known to dampen immune function, resulting in a worsened anti-tumor immune response. Understanding how extrinsic alterations in pH modulate the interactions between immune cells and tumors cells will help elucidate opportunities for new therapeutic approaches. We observed that pH impacts the function of immune cells, both natural killer (NK) and T cells, which is relevant in the context of a highly acidic TME. Decreased NK and T cell activity was correlated with decreasing pH in a co-culture immune cell-mediated tumor cell-killing assay. The addition of pH-modulating drugs cariporide, lansoprazole, and acetazolamide to the co-culture assay was able to partially mitigate this dampened immune cell function. Treatment of colorectal cancer (CRC) cells with NHE1 inhibitor cariporide increased CRC cell-secreted cytokines involved in immune cell recruitment and activation and decreased cytokines involved in epithelial-mesenchymal transition (EMT). Cariporide treatment also decreased CRC cell shed TRAIL-R2, TRAIL-R3, and PD-L1 which is relevant in the context of immunotherapy. These experiments can help inform future investigations into how the pH of the tumor microenvironment may be extrinsically modulated to improve anti-tumor immune response in solid tumors such as colorectal cancer.  相似文献   
45.
Arnadottir IB, Holbrook WP, Eggertsson H, Gudmundsdottir H, Jonsson SH, Gudlaugsson JO, Saemundsson SR, Eliasson ST, Agustsdottir H. Prevalence of dental erosion in children: a national survey. Community Dent Oral Epidemiol 2010; 38: 521–526. © 2010 John Wiley & Sons A/S Abstract – Objectives:  To measure the prevalence of dental erosion in permanent teeth in Iceland as part of the National Oral Health Survey. Methods:  A representative, nationwide sample of 2251 Icelandic children, 20% of those aged 6, 12 and 15 year, was examined. Dental erosion was recorded for all erupted permanent teeth and graded using the modified scale of Lussi. Results:  Erosion was not seen in the permanent teeth of six‐year‐olds, but was present in 15.7% of 12‐year‐olds, more frequently in boys than girls (19.9% boys, 11.0% girls; P < 0.001). Among 15‐year‐olds, dental erosion was seen among 30.7% of subjects (38.3% boys, 22.7% girls; P < 0.001). Severity of erosion was mostly scored as grade I, with only 5.5% of 15‐year‐olds scored as grade II, mostly on tooth 46 (4.3%) and 36 (4.2%). For 12‐year‐olds, 0.9% had erosion scores of grade II mostly on tooth 46 (0.8%) and 36 (0.7%). No subjects had erosion of grade III. The most common clinical manifestation of erosion was the appearance of cup‐like lesions on the cusps of lower first molars. Conclusions: Dental erosion was frequently present by the age of 12; the prevalence doubled by age 15 and was seen almost twice as often among boys than girls. Teeth most frequently showing signs of erosion were the lower first molars. The rapidly growing prevalence of erosion demonstrated by this nationwide survey emphasizes the need for further research into the aetiology of erosion and possible methods of preventing and treating this emerging dental problem.  相似文献   
46.
47.
Background:  Prediction of progression from pre-malignant oral mucosal lesions to malignancy, or recurrence of an existing oral squamous cell carcinoma (OSCC), is an important clinical problem in oral medicine.
Methods:  This study presents a follow-up of a study published in 2002. Samples from 54 patients with OSCC, 45 with oral lichen planus (OLP) and 45 with hyperkeratosis (clinically leukoplakia), diagnosed between 1987 and 1996, were analysed for TP53 protein expression and TP53 mutation. Follow-up was 11–17 years for OSCC (mean 13.3), 12–22 years for OLP (mean 15.9) and 12–17 years for hyperkeratosis (mean 14.5).
Results:  Of the 54 OSCC patients, 28 experienced recurrent disease, 21 died of OSCC, 22 died of other causes. Of the 14 OSCC patients with mutated TP53 ( n  = 11), the cancer recurred in eight (57%) and in 20/39 (51%) without mutation. Expression of TP53 protein was significantly associated with reduced overall survival. Among OLP patients, nine were TP53- mutated out of 31 tested. One TP53- mutated OLP patient developed OSCC in a different site. Of the hyperkeratosis patients, three were mutated of 22 tested. One hyperkeratosis patient (non-mutated) developed OSCC in the same site.
Conclusion:  TP53 mutations can exist in benign oral mucosal lesions for many years without progression to malignancy. No association was found between TP53 protein expression or TP53 mutation and recurrence of OSCC or disease-related survival. Overall survival was reduced in patients with positive TP53 protein expression.  相似文献   
48.
49.
Eleven fine needle aspiration (FNA) biopsies were performed in five children with neuroblastoma, including one patient with peripheral neuroectodermal tumor of the thoracopulmonary region (Askin tumor). Cytologic features in conjunction with immunocytochemistry and electron microscopy on the aspirated material enabled us to make a primary diagnosis in four of the five patients and diagnose local recurrence and metastatic disease in three patients. There were no false-positive or false-negative cytologic diagnoses; therefore, diagnostic accuracy was 100%. FNA is an extremely useful technique for the primary diagnosis and management of neuroblastoma and excludes other small cell malignancies of children. The results of this study and literature review demonstrate that FNA cytology coupled with ancillary techniques of immunocytochemistry and electron microscopy is a rapid, safe, minimally invasive procedure which can aid in the diagnosis and management of patients with neuroblastoma without resorting to more aggressive diagnostic procedures in selective cases.  相似文献   
50.
The effects of two dosage schedules of nicardipine, a calcium-entry blocker, were studied in the pregnant rabbit during induced preterm uterine contractions and compared with the effects of ritodrine hydrochloride. Uterine activity was inhibited by all treatment regimens, but the most significant inhibition was achieved by the higher dose of nicardipine, which nearly abolished all uterine activity. However, while maternal tachycardia and hypotension were observed during treatment with each of these medications, the most significant drop in blood pressure occurred with high-dose nicardipine. These findings may indicate that nicardipine is a potent tocolytic agent with side effects similar in degree, but of different etiology, than those seen with ritodrine. Additional studies to clarify the effect of nicardipine tocolysis on the fetus are needed before it can be considered for use in human pregnancy.  相似文献   
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