全文获取类型
收费全文 | 1252篇 |
免费 | 85篇 |
国内免费 | 15篇 |
专业分类
耳鼻咽喉 | 10篇 |
儿科学 | 19篇 |
妇产科学 | 9篇 |
基础医学 | 133篇 |
口腔科学 | 18篇 |
临床医学 | 88篇 |
内科学 | 290篇 |
皮肤病学 | 7篇 |
神经病学 | 77篇 |
特种医学 | 63篇 |
外科学 | 290篇 |
综合类 | 20篇 |
预防医学 | 57篇 |
眼科学 | 31篇 |
药学 | 64篇 |
中国医学 | 2篇 |
肿瘤学 | 174篇 |
出版年
2024年 | 3篇 |
2023年 | 28篇 |
2022年 | 47篇 |
2021年 | 85篇 |
2020年 | 32篇 |
2019年 | 62篇 |
2018年 | 70篇 |
2017年 | 60篇 |
2016年 | 48篇 |
2015年 | 47篇 |
2014年 | 41篇 |
2013年 | 52篇 |
2012年 | 103篇 |
2011年 | 83篇 |
2010年 | 40篇 |
2009年 | 34篇 |
2008年 | 45篇 |
2007年 | 60篇 |
2006年 | 60篇 |
2005年 | 73篇 |
2004年 | 45篇 |
2003年 | 38篇 |
2002年 | 34篇 |
2001年 | 10篇 |
2000年 | 10篇 |
1999年 | 6篇 |
1998年 | 18篇 |
1997年 | 8篇 |
1996年 | 11篇 |
1995年 | 7篇 |
1994年 | 9篇 |
1993年 | 9篇 |
1991年 | 5篇 |
1990年 | 3篇 |
1989年 | 4篇 |
1988年 | 11篇 |
1987年 | 3篇 |
1986年 | 6篇 |
1985年 | 4篇 |
1984年 | 4篇 |
1983年 | 5篇 |
1982年 | 5篇 |
1981年 | 5篇 |
1980年 | 5篇 |
1977年 | 4篇 |
1975年 | 3篇 |
1971年 | 1篇 |
1966年 | 1篇 |
1912年 | 1篇 |
1911年 | 1篇 |
排序方式: 共有1352条查询结果,搜索用时 15 毫秒
51.
Kimiaki Takagi Makoto Kawase Daiki Kato Kota Kawase Manabu Takai Koji Iinuma Keita Nakane Noriyasu Hagiwara Toru Yamada Masayuki Tomioka Takuya Koie 《Current oncology (Toronto, Ont.)》2022,29(4):2864
Recently, cytoreductive prostatectomy for metastatic prostate cancer (mPCa) has been associated with improved oncological outcomes. This study was aimed at evaluating whether robot-assisted radical prostatectomy (RARP) as a form of cytoreductive prostatectomy can improve oncological outcomes in patients with mPCa. We conducted a retrospective study of twelve patients with mPCa who had undergone neoadjuvant therapy followed by RARP. The endpoints were biochemical recurrence-free survival, treatment-free survival, and de novo metastasis-free survival. At the end of the follow-up period, none of the enrolled patients had died from PCa. The 1- and 2-year biochemical recurrence-free survival rates were 83.3% and 66.7%, respectively, and treatment-free survival rates were 75.0% and 56.3%, respectively. One patient developed de novo bone metastases 6.4 months postoperatively, and castration-resistant prostate cancer 8.9 months postoperatively. After RARP, the median duration of recovery of urinary continence was 5.2 months. One patient had severe incontinence (>2 pads/day) 24 months postoperatively. RARP may be a treatment option in patients with mPCa who have achieved a serum prostate-specific antigen level < 0.2 ng/mL, and present without new lesions on imaging. 相似文献
52.
JY Nagata TF Rocha‐Lima BP Gomes CC Ferraz AA Zaia FJ Souza‐Filho A De Jesus‐Soares 《Australian dental journal》2015,60(3):416-420
Immature avulsed teeth are not usually treated with pulp revascularization because of the possibility of complications. However, this therapy has shown success in the treatment of immature teeth with periapical lesions. This report describes the case of an immature replanted tooth that was successfully treated by pulp revascularization. An 8‐year‐old boy suffered avulsion on his maxillary left lateral incisor. The tooth showed incomplete root development and was replanted after 30 minutes. After diagnosis, revascularization therapy was performed by irrigating the root canal and applying a calcium hydroxide paste and 2% chlorhexidine gel for 21 days. In the second session, the intracanal dressing was removed and a blood clot was stimulated up to the cervical third of the root canal. Mineral trioxide aggregate was placed as a cervical barrier at the entrance of the root canal and the crown was restored. During the follow‐up period, periapical repair, apical closure and calcification in the apical 4 mm of the root canal was observed. An avulsed immature tooth replanted after a brief extra‐alveolar period and maintained in a viable storage medium may be treated with revascularization. 相似文献
53.
Kenta Shinoda Andrea Choe Kiyoshi Hirahara Masahiro Kiuchi Kota Kokubo Tomomi Ichikawa Jason S. Hoki Akane S. Suzuki Neelanjan Bose Judith A. Appleton Raffi V. Aroian Frank C. Schroeder Paul W. Sternberg Toshinori Nakayama 《Proceedings of the National Academy of Sciences of the United States of America》2022,119(9)
Mounting evidence suggests that nematode infection can protect against disorders of immune dysregulation. Administration of live parasites or their excretory/secretory (ES) products has shown therapeutic effects across a wide range of animal models for immune disorders, including asthma. Human clinical trials of live parasite ingestion for the treatment of immune disorders have produced promising results, yet concerns persist regarding the ingestion of pathogenic organisms and the immunogenicity of protein components. Despite extensive efforts to define the active components of ES products, no small molecules with immune regulatory activity have been identified from nematodes. Here we show that an evolutionarily conserved family of nematode pheromones called ascarosides strongly modulates the pulmonary immune response and reduces asthma severity in mice. Screening the inhibitory effects of ascarosides produced by animal-parasitic nematodes on the development of asthma in an ovalbumin (OVA) murine model, we found that administration of nanogram quantities of ascr#7 prevented the development of lung eosinophilia, goblet cell metaplasia, and airway hyperreactivity. Ascr#7 suppressed the production of IL-33 from lung epithelial cells and reduced the number of memory-type pathogenic Th2 cells and ILC2s in the lung, both key drivers of the pathology of asthma. Our findings suggest that the mammalian immune system recognizes ascarosides as an evolutionarily conserved molecular signature of parasitic nematodes. The identification of a nematode-produced small molecule underlying the well-documented immunomodulatory effects of ES products may enable the development of treatment strategies for allergic diseases.Parasitic nematodes are associated with almost all groups of vertebrates, and nearly one-third of the human population is infected with these helminths (1). Their omnipresence is in part due to their ability to modulate host immune responses to prevent immune attack and expulsion (2). The elimination of nematode infections has been proposed as a possible cause of the increased incidence of autoimmune disorders and allergic diseases in developed countries (3), based on epidemiological data showing a correlation between the decline in helminth infection and the rise in allergic and autoimmune diseases, including asthma, multiple sclerosis (MS), type 1 diabetes, and inflammatory bowel diseases (IBDs) (4).The administration of live nematodes or their excretory/secretory (ES) products has shown therapeutic effects across a wide range of animal models for these immune disorders (5–8). The US Food and Drug Administration recently approved live helminth administration as an investigational drug for the treatment of immune disorders, and relevant human clinical trials are ongoing (9). Despite mounting evidence that helminths have significant therapeutic potential, we do not yet have a comprehensive understanding of the molecules that underlie their immunomodulatory effects; and, in particular, the possible relevance of low-molecular-weight components of ES products has remained largely unexplored.A wide range of nematodes, including many parasitic species, produce ascarosides, a family of small-molecule signals based on glycosides of the dideoxysugar ascarylose (10). Ascarosides have not yet been identified in any other animal phylum, suggesting that they may be a nematode-specific class of small molecules (SI Appendix, Fig. S1A). The first ascaroside-based signaling molecules were identified in the free-living model nematode Caenorhabditis elegans (11, 12). Ascarosides regulate almost every aspect of C. elegans life history, including diapause (dauer) induction, aging, mate finding, and aggregation (11, 12). Subsequently, ascarosides have been shown to be detected by organisms other than nematodes, such as nematophagous fungi that set traps to capture and digest nematodes (13). The perception of ascarosides is sufficient to trigger trap formation in these fungi, demonstrating their longstanding evolutionary association with nematodes. Furthermore, ascarosides produced by plant-pathogenic nematodes have been shown to trigger innate immune responses in monocot and dicot plants (14). Cumulatively, these findings suggest that ascarosides represent a nematode-specific molecular signature that is recognized and interpreted by nematode predators and hosts across multiple kingdoms.In this study, we collected ES products from the gut-resident, rodent-parasitic nematode Nippostrongylus brasiliensis. Previous studies showed that the administration of N. brasiliensis ES (NES) products fully inhibits the development of airway hyperresponsiveness (AHR) in the ovalbumin (OVA) murine model of asthma (15). Specifically, NES products substantially prevented lung eosinophilia, mucus production, and resistance to airflow. Notably, it was found that heat-treated or proteinase K–treated NES mimicked the full effect of untreated NES products in reducing lung eosinophilia and OVA-specific IgG in serum. Therefore, we hypothesized that the therapeutic effect of NES products may be due to the presence of specific small molecules that may in part be bound to secreted proteins, explaining the activity of heat- or proteinase K–treated NES. To test this hypothesis, we isolated the small molecule fraction of heat-treated NES (small molecule ES [smES]) products via filtration through a 3-kDa filter and found that smES products strongly suppresses OVA-induced allergic immune responses. Parallel chemical analyses of several other mammalian parasitic nematodes confirmed the presence of specific ascarosides in smES products of all tested species. Next, we tested synthetic samples of ascarosides and found that ascr#7, a compound produced by N. brasiliensis and other parasitic species, markedly inhibited the development of allergic airway inflammation, comparable to the full effect of smES products. Mechanistically, we found that ascr#7 administration attenuated IL-33 production from lung epithelial cells and suppressed the proliferation of memory-type IL-5–producing pathogenic T helper 2 (Th2) cells and type 2 innate lymphoid cells (ILC2s) in the lung, both key drivers for the pathology of asthma. We thus demonstrate that ascarosides have an immunomodulatory role that attenuates OVA-induced allergic inflammation in a murine model. 相似文献
54.
Kota Ouchi Shin Takahashi Akira Okita Yasuhiro Sakamoto Osamu Muto Kenji Amagai Takaho Okada Hisatsugu Ohori Eiji Shinozaki Chikashi Ishioka 《Cancer science》2022,113(3):1057
DNA methylation status correlates with clinical outcomes of anti‐epidermal growth factor receptor (EGFR) treatment. There is a strong need to develop a simple assay for measuring DNA methylation status for the clinical application of drug selection based on it. In this study, we collected data from 186 patients with metastatic colorectal cancer (mCRC) who had previously received anti‐EGFR treatment. We modified MethyLite to develop a novel assay to classify patients as having highly methylated colorectal cancer (HMCC) or low‐methylated colorectal cancer (LMCC) based on the methylation status of 16 CpG sites of tumor‐derived genomic DNA in the development cohort (n = 30). Clinical outcomes were then compared between the HMCC and LMCC groups in the validation cohort (n = 156). The results showed that HMCC had a significantly worse response rate (4.2% vs 33.3%; P = .004), progression‐free survival (median: 2.5 vs 6.6 mo, P < .001, hazard ratio [HR] = 0.22), and overall survival (median: 5.6 vs 15.5 mo, P < .001, HR = 0.23) than did LMCC in patients with RAS wild‐type mCRC who were refractory or intolerable to oxaliplatin‐ and irinotecan‐based chemotherapy (n = 101). The DNA methylation status was an independent predictive factor and a more accurate biomarker than was the primary site of anti‐EGFR treatment. In conclusion, our novel DNA methylation measurement assay based on MethyLight was simple and useful, suggesting its implementation as a complementary diagnostic tool in a clinical setting. 相似文献
55.
The social implementation of knowledge and technologies that are effective in epidemiological and observational studies is essential for solving social issues. In particular, there have been few attempts to implement clinical practices and information communication technologies that utilize data in the field. We describe the four stages of social implementation: 1) redefining social issues as solvable problems, 2) finding technological solutions to solvable problems, 3) social implementation contributing to the solutions, and 4) horizontal deployment of effective methods for solving social issues. Introducing a use case of artificial intelligence (AI) social implementation in child-abuse response conducted by our team, we discuss pitfalls and tips as a frame of reference to demonstrate data utilization as social infrastructure for solving social issues and to consider practical solutions in a logical manner.Key words: child abuse, child maltreatment, AI, implementation, machine learning 相似文献
56.
Mutations in the LEMD3 gene were recently incriminated in Buschke–Ollendorff syndrome (BOS) and osteopoikilosis, with or without melorheostosis. The relationship of this gene with isolated sporadic melorheostosis is less clear. We investigated LEMD3 in a two-generation BOS family showing an extremely variable expression of the disease, in a sporadic patient with skin features of BOS, and in an additional subject with isolated melorheostosis. We identified two different mutations, both resulting in a premature stop codon, in the two cases of BOS. The mutation (c.2564G>A) reported in the familial case is novel, while that observed in the sporadic case (c.1963C>T) has been previously reported in an American woman with osteopoikilosis and melorheostosis who had a family history of isolated osteopoikilosis. The search for mutations in DNA extracted from the peripheral blood, as well as skin and bone biopsies of the patient with melorheostosis failed to identify any pathogenic change. Our results further expand the LEMD3 mutation repertoire, corroborate the extreme interfamilial and intrafamilial clinical variability of LEMD3 mutations, and underline the lack of a clear phenotype–genotype correlation in BOS. The present study supports the general conclusion that LEMD3 mutations do not contribute to isolated sporadic melorheostosis. The genetic or epigenetic influences that are responsible for the development of melorheostosis require further investigation. 相似文献
57.
Jagannath Kota Krishna K Machavaram Danielle N McLennan Glenn A Edwards Christopher J H Porter Susan A Charman 《Drug metabolism and disposition》2007,35(12):2211-2217
The relative contribution of the lymph and blood in the absorption of darbepoetin alfa (DA) from different s.c. injection sites was determined using a central lymph-cannulated sheep model. DA was administered to parallel groups either as a bolus i.v. injection (0.5 mug/kg) into the jugular vein or as a bolus s.c. injection (2 mug/kg) into the interdigital space, the abdomen, or the shoulder. In the lymph-cannulated groups, the thoracic lymph duct was cannulated for continuous collection of central lymph, and blood samples were periodically collected via the jugular vein in all the groups. The concentration of DA in serum and lymph was determined by enzyme-linked immunosorbent assay. The total fraction of the dose reaching the systemic circulation and the fractions absorbed via the lymph and the blood were determined. A pharmacokinetic model was constructed to simultaneously fit the data from all the treatment groups. Absorption was essentially complete for all three injection sites in non-lymph-cannulated s.c. groups, but the rates of absorption differed significantly. Based on the modeling results for the lymph-cannulated groups, the lymphatics represented the predominant absorption route for both the interdigital (90 +/- 1%) and the abdomen (67 +/- 9%) injection sites. Fluorescein isothiocyanate dextran visualization studies revealed that the lymph draining the shoulder injection site entered the thoracic lymph duct distal to the point of cannulation, effectively precluding collection of thoracic lymph from this site. For that reason, the contribution of the lymphatics following injection in the shoulder could not be determined using these cannulation procedures. 相似文献
58.
Subsequent activation of mitogen-activated protein kinase after adhesion of transitional cell cancer cells to fibronectin 总被引:1,自引:0,他引:1
INTRODUCTION: In the process of tumor invasion and metastasis, interactions between tumor cells and extracellular matrix play a crucial role. Recently, it was shown that fibronectin binding to fibronectin receptor promotes mitogen-activated protein kinase (MAPK) activation after tyrosine phosphorylation of focal adhesion kinase (FAK). We investigated these signal transduction events in transitional cell cancer (TCC) cells. MATERIALS AND METHODS: (1) The adhesion of T24 cells, a fibronectin-receptor-positive TCC cell line, to fibronectin was investigated; (2) the MAPK activation after fibronectin stimulation in bladder cancer cell lines was examined by Western blotting using an antiactive MAPK antibody, and (3) FAK, Sos, and Grb-2 were also examined by Western blot analysis. RESULTS AND CONCLUSIONS: T24 cells adhered to fibronectin-coated dishes more quickly than to the noncoated dishes. Fibronectin stimulation induced activation of MAPK in T24, SCaBER, and HT1376 cells. However, activated MAPK was not detected in RT4 cells which do not express alpha(5)beta(1) integrin (major fibronectin receptor) after fibronectin stimulation. T24, SCaBER, and HT1376 expressed FAK and Sos. RT4 showed little FAK and Sos expression. Grb-2 was expressed in all cell lines. Adhesion of fibronectin-receptor-positive TCC cells to fibronectin activates the MAPK cascade, possibly resulting in activation of tumor cells. 相似文献
59.
BACKGROUND/AIM: Caveolin, which is a major constructive component of the caveolar membranes, plays a key role in transcytosis of molecules into cells and regulation of several signal transductions. Caveolin has three isoforms, and recent studies suggest that in some malignant tumors an alteration of caveolin-1 expression correlates with oncogenetic changes. Caveolins have been reported to be negative regulators of inducible nitric oxide synthase (iNOS) which can provoke an antitumor response via infiltrating immune cells. The aim of this study was to examine the expressions of caveolin-1 and caveolin-3 (which is a caveolin-1 homologue localized predominantly in muscle tissue) in testicular cancer. METHODS: We evaluated the expressions of caveolin-1, caveolin-3, and iNOS in 16 seminoma and 10 non-seminoma testicular cancer specimens as well as normal testicular tissue, using a streptavidin-biotin bridge technique on cryostat sections. The expression of caveolin-3 was confirmed by slot-blot analysis. Tumor-infiltrating immune cells were also studied immunohistochemically, and the correlation between the number of immune cells and caveolin-3 concentrations was calculated. RESULTS: Immunohistochemistry revealed that caveolin-3, but not caveolin-1, was frequently expressed in seminomas (12 positive out of 16 specimens) without positive staining in their normal counterparts or in nonseminomatous germ cell tumors, except for muscle components in the teratoma. iNOS was not expressed in any tissues examined. Samples with high levels of caveolin-3 tended to have higher degrees of tumor-infiltrating immune cells, although this finding was not statistically significant. CONCLUSION: This is the first report demonstrating the involvement of caveolin-3 in germ cell tumors. 相似文献
60.
Kota Z Horvath LI Droppa M Horvath G Farkas T Pali T 《Proceedings of the National Academy of Sciences of the United States of America》2002,99(19):12149-12154
The development of the thylakoid membrane was studied during illumination of dark-grown barley seedlings by using biochemical methods, and Fourier transform infrared and spin label electron paramagnetic resonance spectroscopic techniques. Correlated, gross changes in the secondary structure of membrane proteins, conformation, composition, and dynamics of lipid acyl chains, SDS/PAGE pattern, and thermally induced structural alterations show that greening is accompanied with the reorganization of membrane protein assemblies and the protein-lipid interface. Changes in overall membrane fluidity and noncovalent protein-lipid interactions are not monotonic, despite the monotonic accumulation of chlorophyll, LHCII [light-harvesting chlorophyll a/b-binding (polypeptides) associated with photosystem II] apoproteins, and 18:3 fatty acids that follow a similar time course with highest rates between 12-24 h of greening. The 18:3 fatty acid content increases 2.8-fold during greening. This appears to both compensate for lipid immobilization by membrane proteins and facilitate packing of larger protein assemblies. The increase in the amount of protein-solvating immobile lipids, which reaches a maximum at 12 h, is caused by 40% decrease in the membranous mean diameter of protein assemblies at constant protein/lipid mass ratio. Alterations in the SDS/PAGE pattern are most significant between 6-24 h. The size of membrane protein assemblies increases approximately 4.5-fold over the 12-48-h period, likely caused by the 2-fold gain in LHCII apoproteins. The thermal stability of thylakoid membrane proteins increases monotonically, as detected by an increasing temperature of partial protein unfolding during greening. Our data suggest that a structural coupling between major protein and lipid components develops during greening. This protein-lipid interaction is required for the development and protection of thylakoid membrane protein assemblies. 相似文献