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941.
Our major theme is that the layered structure of the endothelial barrier requires continuous activation of signalling pathways regulated by sphingosine‐1‐phosphate (S1P) and intracellular cAMP. These pathways modulate the adherens junction, continuity of tight junction strands, and the balance of synthesis and degradation of glycocalyx components. We evaluate recent evidence that baseline permeability is maintained by constant activity of mechanisms involving the small GTPases Rap1 and Rac1. In the basal state, the barrier is compromised when activities of the small GTPases are reduced by low S1P supply or delivery. With inflammatory stimulus, increased permeability can be understood in part as the action of signalling to reduce Rap1 and Rac1 activation. With the hypothesis that microvessel permeability and selectivity under both normal and inflammatory conditions are regulated by mechanisms that are continuously active, it follows that when S1P or intracellular cAMP are elevated at the time of inflammatory stimulus, they can buffer changes induced by inflammatory agents and maintain normal barrier stability. When endothelium is exposed to inflammatory conditions and subsequently exposed to elevated S1P or intracellular cAMP, the same processes restore the functional barrier by first re‐establishing the adherens junction, then modulating tight junctions and glycocalyx. In more extreme inflammatory conditions, loss of the inhibitory actions of Rac1‐dependent mechanisms may promote expression of more inflammatory endothelial phenotypes by contributing to the up‐regulation of RhoA‐dependent contractile mechanisms and the sustained loss of surface glycocalyx allowing access of inflammatory cells to the endothelium. 相似文献
942.
Mohamed Khalifa Jennifer Stein Lance Grau Valery Nelson Jeanne Meck Swaroop Aradhya John Duby 《American journal of medical genetics. Part A》2013,161(4):835-840
KBG syndrome (OMIM 148050) is a very rare genetic disorder characterized by macrodontia, distinctive craniofacial abnormalities, short stature, intellectual disability, skeletal, and neurologic involvement. Approximately 60 patients have been reported since it was first described in 1975. Recently mutations in ANKRD11 have been documented in patients with KBG syndrome, and it has been proposed that haploinsufficiency of ANKRD11 is the cause of this syndrome. In addition, copy number variation in the 16q24.3 region that includes ANKRD11 results in a variable phenotype that overlaps with KBG syndrome and also includes autism spectrum disorders and other dysmorphic facial features. In this report we present a 2½‐year‐old African American male with features highly suggestive of KBG syndrome. Genomic microarray identified an intragenic 154 kb deletion at 16q24.3 within ANKRD11. This child's mother was mosaic for the same deletion (present in approximately 38% of cells) and exhibited a milder phenotype including macrodontia, short stature and brachydactyly. This family provides additional evidence that ANKRD11 causes KBG syndrome, and the mild phenotype in the mosaic form suggests that KBG phenotypes might be dose dependent, differentiating it from the more variable 16q24.3 microdeletion syndrome. This family has additional features that might expand the phenotype of KBG syndrome. © 2013 Wiley Periodicals, Inc. 相似文献
943.
944.
Antonija Jurela Dario Repic Slavica Pejda Hrvoje Juric Renata Vidakovic Igor Matic Andrija Bosnjak 《The Angle orthodontist》2013,83(1):140
Objective:To determine the difference in the levels of Streptococcus mutans and S sobrinus in stimulated saliva in orthodontic patients with different bracket types (stainless steel and esthetic brackets) using polymerase chain reaction and cultivation method.Materials and Methods:Thirty-two patients, aged 13 to 30 years, were selected following these criteria: 1) orthodontic treatment indication, 2) systemic health, and 3) no tobacco and antibiotic consummation for three months prior to the commencement of the study. Patients were divided into two groups according to the bracket type; 16 patients formed the conventional bracket group (stainless steel brackets), and 16 patients formed the esthetic bracket group (plastic brackets). The levels of S mutans and S sobrinus in stimulated whole saliva samples were collected prior to fixed orthodontic appliance placement (T1) and 12 weeks after placement (T2), as were the Decayed, Missing, and Filled Surface Index (DMFS) and Oral Hygiene Index-Simplified (OHI-S). Mann-Whitney, Wilcoxon, and chi-square tests were used for statistical analysis.Results:Statistical analysis (chi-square test) showed no difference in S mutans and S sobrinus counts among patients with different brackets at either T1 or T2. There was no difference in total bacteria counts after fixed orthodontic appliance placement.Conclusion:The number of colony-forming units of S mutans and S sobrinus in stimulated saliva samples does not seem to be significantly different between patients with stainless steel brackets and patients with plastic brackets. 相似文献
945.
Neil Edgerton M.D. Cynthia Cohen M.D. Momin T. Siddiqui M.D. F.I.A.C. 《Diagnostic cytopathology》2013,41(1):35-40
The CINtec PLUS® system is an immunohistochemical cocktail composed of antibodies against p16INK4a (surrogate of HPV infection) and Ki‐67 (proliferation marker) meant to improve the sensitivity and specificity for detecting high‐grade dysplasia (HGD). In the presence of dysplasia, a red chromogen marks Ki‐67 expression in the nucleus and a brown chromogen marks cytoplasmic p16INK4a expression. Only cells showing dual staining are interpreted as positive. This retrospective study examined the performance of CINtec PLUS testing when performed on ASC‐US diagnosed samples. Comparison was made to high‐risk HPV DNA test results and colposcopic biopsy results. Technical considerations in the interpretation of this immunohistochemical stain are additionally discussed. CINtec PLUS showed modest sensitivity (64%) and specificity (53%) in identifying the presence of HGD at surgical biopsy. Positive and negative predictive values for HGD were 28% and 83%, respectively. HR‐HPV DNA test yielded sensitivity of 100% and specificity of 21%. During interpretation, squamous metaplasia and endocervical cells were seen to show individual staining for p16INK4a or Ki‐67. Individual staining, when present within three dimensional cellular groups common to SurePath® preparations, can be time‐intensive to interpret necessitating thoughtful examination at high power. The Pap test with HR‐HPV DNA testing is a highly sensitive test. A specific test is needed to prevent false positives and over treatment. The CINtec® system provides a modest increase in specificity beyond HR‐HPV DNA testing. Future study of its appropriateness and cost‐ffectiveness in a treatment algorithm are warranted. Diagn. Cytopathol. 2013. © 2011 Wiley Periodicals, Inc. 相似文献
946.
Qingzhu Wei Bo Fu Jianghuan Liu Jiabao Xu Tong Zhao 《International journal of clinical and experimental pathology》2013,6(8):1549-1557
Currently, there are discrepancies in the interpretation between cervical liquid-based cytology (LBC) and histologic diagnoses. The aim of our study was to evaluate the utility of p16INK4a (p16) and IMP3 staining of LBC specimens to increase the concordance rate. A total of 98 cell blocks with biopsy results, including 37 low-grade squamous intraepithelial lesions (LSIL), 36 high-grade squamous intraepithelial lesions (HSIL), and 25 squamous cell carcinomas (SCC), were selected for the immunocytochemical analysis of p16 and IMP3. The LBC diagnoses corresponded with histological diagnoses for 59.5% (22/37), 63.9% (23/36), and 88.0% (22/25) of LSIL, HSIL, and SCC lesions, respectively. We found a high frequency of p16 positivity in HSIL (72.2%) and SCC (100%), but not LSIL (29.7%). IMP3 was frequently expressed in SCC (84.0%), but rarely in LSIL (8.1%) and HSIL (25.0%). Cervical intraepithelial neoplasia 1 (CIN1) was negative for both p16 and IMP3, CIN2/3 tended to be positive for p16 and negative for IMP3, and SCC was positive for both p16 and IMP3. The combination of p16 and IMP3 immunostaining had a higher sensitivity and specificity for detecting CIN1 and CIN2/3 than cytology. For detecting SCC, p16/IMP3 had a higher sensitivity than cytology, but a lower specificity. IMP3 is a useful diagnostic immunomarker that can be used to identify SCC and the combination of p16/IMP3 expression was found to improve the discrepant results between cytologic and histologic diagnoses. 相似文献
947.
948.
Athanasios I. Zavras Gregory E. Rosenberg Jared D. Danielson Vassiliki M. Cartsos 《Journal of the American Dental Association (1939)》2013,144(9):1014-1021
BackgroundAccording to the U.S. Centers for Disease Control and Prevention, 48 percent of Americans (roughly 144 million people) used at least one prescribed medication in the preceding month; 11 percent used five or more. The authors describe the U.S. Food and Drug Administration's (FDA's) MedWatch program, the safety surveillance system for drugs and devices in the United States, and the dentist's role with regard to voluntary reporting of adverse effects (AEs). They also identify the most frequent AEs in the oral cavity as reported in the FDA Adverse Event Reporting System (FAERS).MethodsThe authors reviewed the literature regarding MedWatch, and they mined data in the FAERS public database for the 100 most commonly prescribed medications and their associated AEs.ResultsPharyngitis was the most common AE. Cough, dysgeusia and dysphagia also were common.ConclusionThe MedWatch program and its related databases contain useful information about AEs of pharmaceuticals and devices manifested in the oral cavity. Increased participation in the reporting of suspected adverse reactions will improve the national surveillance system and ultimately will protect patients' safety.Practical ImplicationsAs pharmaceutical consumption increases exponentially for a growing segment of the population, and as innovation in dental technology and devices flourishes, dentists have a distinct role in safeguarding patients' well-being. Promptly reporting AEs in the oral cavity improves quality of care and protects patients' well-being. 相似文献
949.
950.