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排序方式: 共有635条查询结果,搜索用时 11 毫秒
21.
Thientunyakit Tanyaluck Sethanandha Chakmeedaj Muangpaisan Weerasak Chawalparit Orasa Arunrungvichian Kuntarat Siriprapa Tossaporn Vichianin Yudthaphon Kamal Swatabdi Suppasilp Chaiyawat Thongpraparn Thonnapong Chanachai Rujaporn Gelovani Juri G. 《Annals of nuclear medicine》2020,34(5):337-348
Annals of Nuclear Medicine - The current study was conducted to improve the understanding of relationships between regional cortical amyloid load, glucose metabolism, cortical morphology (volume),... 相似文献
22.
Antonello D rea Juri Radmilovic reina Carbone Alberto Forni Ercole Tagliamonte Lucia Riegler Biagio Liccardo Fabio Crescibene Cesare Sirignano Giovanna Esposito Eduardo Bossone 《World journal of radiology》2020,12(11):261-271
The integrated clinical, laboratory and ultrasound approach is essential for the diagnosis, evaluation and monitoring of the patient's therapy in coronavirus disease 2019 pneumonia. The ideal imaging approach in this context is not yet well defined. Chest X-ray is characterized by low sensitivity in identifying earlier lung changes. The "bedside" pulmonary ultrasound has an undeniable series of advantages in the patient at high infectious risk and can provide incremental data in the respiratory intensive care for the serial control of the individual patient as well as for the home delivery of the stabilized subjects. Pulmonary computed tomography shows high sensitivity but should not be routinely performed in all patients, because in the first 48 h it can be absolutely negative and in the late phase the imaging findings may not change the therapeutic approach. Echocardiography should be limited to patients with hemodynamic instability to assess ventricular function and pulmonary pressures. 相似文献
23.
The outcome of root canal treatment is based on efficient disinfection of the root canal system and prevention of reinfection. Current chemomechanical cleaning methods do not always achieve these goals, and insufficient root canal disinfection is the main reason for endodontic failure. Due to high energy content and specific characteristics of laser light, laser treatment has been proposed for cleaning and disinfecting the root canal system. This paper reviews the literature covering the effect of Er:YAG, Er,Cr:YSGG, Nd:YAG and diode laser on the root canal wall in the removal of smear layer and against intracanal bacteria. Recently, the use of laser energy to induce cavitation and acoustic streaming of intracanal irrigants has been investigated. Based on recent literature, it can be concluded that lasers have bactericidal effects. However, they still cannot replace sodium hypochlorite and should be considered as an adjunct to the current chemical root canal disinfection protocols. Certain lasers can help in removing the smear layer and debris and can modify the morphology of the root canal wall. Unfortunately, there have not been enough randomized clinical studies evaluating endodontic treatment outcome following the use of laser.Key words: Disinfection, Root Calan Preparation; Laser Therapy, Low-Level; Smear Layer 相似文献
24.
Masahiro To Yohei Kamata Juri Saruta Tomoko Shimizu Takenori Sato Yusuke Kondo Takashi Hayashi Nobushiro Hamada Keiichi Tsukinoki 《ACTA HISTOCHEMICA ET CYTOCHEMICA》2013,46(1):25-34
It is important to understand the onset of periodontal disease in terms of bacterial infection and host factors. Host-bacteria interactions can be elicited in human cultured cells and animal models, but these models provide only limited biological information about human host reactions against bacterial attacks. Development of an in vivo model using human gingival tissue is needed. We established an in vivo model using nu/nu mice and evaluated host defense following bacterial infection in human gingiva. Human gingival samples were collected from periodontitis patients and transplanted in nu/nu mouse subdermis. After 2 weeks, human characteristics were confirmed by positive immunohistochemical reactions for human-specific markers. We used this model to investigate human β-defensin-2 (hBD-2), an antimicrobial peptide that contributes to initial defense against bacterial invasion. Using real-time polymerase chain reaction, in situ hybridization, and immunohistochemistry, we investigated whether hBD-2 expression was induced in human gingiva as a response to Porphyromonas gingivalis as a periodontal pathogen. Two hours after infection with bacteria, we detected increased expression of hBD-2 mRNA, which was localized in the epithelium of human gingiva. Using our in vivo model, we concluded that increased hBD-2 may play an important role in early defense from bacterial infection in human gingival epithelium. 相似文献
25.
Schiby G Polak-Charcon S Mardoukh C Rosenblatt K Goldberg I Kneller A Rosner M Kopolovic J 《Human pathology》2007,38(3):435-442
Many studies have been performed on chromosomal aberrations of extranodal marginal zone lymphomas. However, only a few have been published so far on ocular adnexal marginal zone lymphomas. We studied 18 cases of orbital lymphoid cell infiltrates. Using fluorescence in situ hybridization (FISH), we studied some of the most common chromosomal aberrations found in extranodal marginal zone lymphomas as: trisomies 3, and rearrangements of the 18q21 MALTI gene to detect the translocations t(11;18)(q21;q21) and t(14;18)(q32;q21)MALT1. Our goals were as follows: (1) study those aberrations in our material and compare them with the literature, (2) check their prognostic significance, and (3) check whether studying those aberrations with FISH can be used as a diagnostic tool to differentiate reactive from neoplastic infiltrates, in addition to immunohistochemistry and polymerase chain reaction. We found a high frequency of trisomies 3 (68%) and 18 (56.6%), the highest published so far in orbital lymphomas. On the other hand, no rearrangement was seen in any of our cases. The histologic picture and the clinical course were the same when there was one or more aberrations. As for the diagnostic significance, the presence of a prior, concurrent, or subsequent lymphoma in almost all the positive for aberrations cases suggests that either the orbital infiltrates in these cases are lymphomas, or they have, at least, a malignant potential or a genetic instability. Therefore, the demonstration of these numerical aberrations by FISH may be an additional sensitive, reliable, and relatively simple tool to differentiate reactive from neoplastic orbital lymphoid cell infiltrates when the immunohistochemistry and polymerase chain reaction, performed in a busy and routine-based histopathology laboratory, are unsatisfactory. 相似文献
26.
Cellular localization of complement C3 and C4 transcripts in intestinal specimens from patients with Crohn's disease 下载免费PDF全文
Laufer J Oren R Goldberg I Horwitz A Kopolovic J Chowers Y Passwell JH 《Clinical and experimental immunology》2000,120(1):30-37
It has been suggested that the increase in C3 and C4 levels in jejunal perfusates of patients with Crohn's disease (CD) results from local intestinal synthesis of complement. The present study evaluated the expression of these complement genes in inflamed tissues from patients with CD. Surgically resected specimens from patients with CD and control tissue obtained from subjects with adenocarcinoma of the colon were evaluated for C3 and C4 gene expression by the use of 35S-labelled anti-sense RNA probes. All tissue samples, diseased and normal tissue, expressed C4 mRNA throughout in the intestinal epithelium. C3 mRNA was not detected in epithelial cells in histologically normal tissue, but in diseased specimens there was a focal distribution of C3 mRNA in epithelial cells of the crypts, but not in villous epithelium. Focal C3 gene expression correlated with crypt abscess formation and the presence of polymorphonuclear leucocytes in the lumen of the crypts. In addition, C3 mRNA was also found in macrophages of the submucosa. These macrophages were CD68+, fusiform with faint cytoplasm and morphologically different from the large rounded lamina propria macrophages, which do not express C3 mRNA. Multinucleated giant cells did not express either C3 or C4 genes. In addition to its presence in intestinal epithelium, C4 mRNA was also expressed in mast cells, which however did not express C3 mRNA. These observations identify cells in the intestinal wall expressing complement genes and support the hypothesis that there is local regulated production of complement in the intestine of patients with CD, and subsequent complement activation may contribute to the inflammatory process. 相似文献
27.
Sabine Vollstädt‐Klein Svenja Wichert Juri Rabinstein Mira Bühler Oliver Klein Gabriele Ende Derik Hermann Karl Mann 《Addiction (Abingdon, England)》2010,105(10):1741-1749
Aims During the development of drug addiction, initial hedonic effects decrease when substance use becomes habitual and ultimately compulsive. Animal research suggests that these changes are represented by a transition from prefrontal cortical control to subcortical striatal control and within the striatum from ventral to dorsal domains of the striatum, but only limited evidence exists in humans. In this study we address this hypothesis in the context of alcohol dependence. Design, setting and participants Non‐abstinent heavy social drinkers (n = 21, 5.0 ± 1.5 drinks/day, 13 of them were alcohol‐dependent according to DSM‐IV) and light social drinkers (n = 10, 0.4 ± 0.4 drinks/day) were examined. Measurements We used a cue‐reactivity functional magnetic resonance imaging (fMRI) design during which pictures of alcoholic beverages and neutral control stimuli were presented. Findings In the dorsal striatum heavy drinkers showed significant higher activations compared to light drinkers, whereas light social drinkers showed higher cue‐induced fMRI activations in the ventral striatum and in prefrontal areas compared to heavy social drinkers [region of interest analyses, P < 0.05 false discovery rate (FDR)‐corrected]. Correspondingly, ventral striatal activation in heavy drinkers correlated negatively with obsessive‐compulsive craving, and furthermore we found a positive association between cue‐induced activation in the dorsal striatum and obsessive‐compulsive craving in all participants. Conclusions In line with our hypothesis we found higher cue‐induced activation of the ventral striatum in social compared to heavy drinkers, and higher dorsal striatal activation in heavy drinkers. Increased prefrontal activation may indicate that social drinkers activate cortical control when viewing alcohol cues, which may prevent the development of heavy drinking or alcohol dependence. Our results suggest differentiating treatment research depending on whether alcohol use is hedonic or compulsive. 相似文献
28.
Mourelatos Z Dostie J Paushkin S Sharma A Charroux B Abel L Rappsilber J Mann M Dreyfuss G 《Genes & development》2002,16(6):720-728
Gemin3 is a DEAD-box RNA helicase that binds to the Survival of Motor Neurons (SMN) protein and is a component of the SMN complex, which also comprises SMN, Gemin2, Gemin4, Gemin5, and Gemin6. Reduction in SMN protein results in Spinal muscular atrophy (SMA), a common neurodegenerative disease. The SMN complex has critical functions in the assembly/restructuring of diverse ribonucleoprotein (RNP) complexes. Here we report that Gemin3 and Gemin4 are also in a separate complex that contains eIF2C2, a member of the Argonaute protein family. This novel complex is a large approximately 15S RNP that contains numerous microRNAs (miRNAs). We describe 40 miRNAs, a few of which are identical to recently described human miRNAs, a class of small endogenous RNAs. The genomic sequences predict that miRNAs are likely to be derived from larger precursors that have the capacity to form stem-loop structures. 相似文献
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