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排序方式: 共有422条查询结果,搜索用时 15 毫秒
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Rutger L. van Bezooijen Marco C. DeRuiter Nathalie Vilain Rui M. Monteiro Annemieke Visser Lianne van der Wee‐Pals Conny J. van Munsteren Pancras C.W. Hogendoorn Michel Aguet Christine L. Mummery Socrates E. Papapoulos Peter Ten Dijke Clemens W.G.M. Löwik 《Developmental dynamics》2007,236(2):606-612
Spatial-temporal regulation of bone morphogenetic protein (BMP) and Wnt activity is essential for normal cardiovascular development, and altered activity of these growth factors causes maldevelopment of the cardiac outflow tract and great arteries. In the present study, we show that SOST, a Dan family member reported to antagonize BMP and Wnt activity, is expressed within the medial vessel wall of the great arteries containing smooth muscle cells. The ascending aorta, aortic arch, brachiocephalic artery, common carotids, and pulmonary trunk were all associated with SOST expressing smooth muscle cells, while the heart itself, including the valves, and more distal arteries, that is, pulmonary arteries, subclavian arteries, and descending aorta, were negative. SOST was expressed from embryonic day 15.5 up to the neonatal period. SOST expression, however, did not correspond with inhibition of Smad-dependent BMP activity or beta-catenin-dependent Wnt activity in the great arteries. Activity of both signaling pathways was already down-regulated before induction of SOST expression. 相似文献
3.
Conny J. van der Laken Otto C. Boerman Wim J. G. Oyen Marjo T. P. van de Vent Roland A. M. J. Claessens Jos W. M. van der Meere Frans H. M. Corstens 《European journal of nuclear medicine and molecular imaging》1996,23(11):1531-1535
Recently, we demonstrated that radiolabelled interleukin-l (IL-1) specifically accumulates in focal infection in mice through interaction with its receptor. Unfortunately, systemic side-effects of IL-1 limit its clinical application. We investigated whether this problem could be circumvented by using the interleukin-1 receptor antagonist (IL-Ira), an equally sized protein that binds to the same receptors as IL-1 without induction of biological effects. Biodistribution of125I-IL-1 and125I-IL-Ira was determined in Swiss mice withStaphylococcus aureus-induced abscesses in the left calf muscle at 4, 12, 24 and 48 h after injection of either 0.4 MBq125I-IL1 or 0.4 MBq125I-IL-Ira. In vitro, the proteins displayed similar binding characteristics. High-performance liquid chromatographic analysis revealed a tendency for IL-Ira to associate with serum proteins. Both proteins rapidly cleared from most organs. However, the abscess uptake of125I-IL-Ira was significantly lower than that of125I-IL-1 at all time points (48 h p.i.: 0.06±0.01%ID/g vs 0.60±0.04%ID/g;P<0.02). The abscess-to-contralateral muscle ratios did not exceed 15.5±2.9 for125I-IL-lra, while the ratios for125I-IL-1 reached 46.9±5.7 at 48 h p.i. Despite similar in vitro receptor binding, the abscess uptake of IL-Ira was much lower than that of IL-1. The interaction of IL-Ira with serum proteins in vivo may reduce its availability for receptor binding in the infection. Although on theoretical grounds IL-Ira is very interesting, these characteristics will prevent its development as a clinically useful radiopharmaceutical to image infection. 相似文献
4.
Heidi Fiegl Conny Gattringer Andreas Widschwendter Alois Schneitter Angela Ramoni Daniela Sarlay Inge Gaugg Georg Goebel Hannes M Müller Elisabeth Mueller-Holzner Christian Marth Martin Widschwendter 《Cancer epidemiology, biomarkers & prevention》2004,13(5):882-888
This proof of principle study aimed to define a new and simple strategy for detection of endometrial cancer using epigenetic markers. We investigated DNA isolated from vaginal secretion collected from tampon for aberrant methylation of five genes (CDH13, HSPA2, MLH1, RASSF1A, and SOCS2) using MethyLight in 15 patients with endometrial cancer and 109 patients without endometrial cancer. All endometrial cancer patients revealed three or more methylated genes, whereas 91% (99 of 109) of the patients without endometrial cancer had no or fewer than three genes methylated in their vaginal secretion. The methods developed in this study provide the basis for a prospective clinical trial to screen asymptomatic women who are at high risk for endometrial cancer. 相似文献
5.
Rusman Tamara John Marie-Luise B. van der Weijden Mignon A. C. Boden Bouke J. H. van der Bijl Carmella M. A. Bruijnen Stefan T. G. van der Laken Conny J. Nurmohamed Mike T. van der Horst-Bruinsma Irene E. 《Clinical rheumatology》2020,39(5):1521-1529
Clinical Rheumatology - The primary aim is to evaluate signs of inflammation on MRI of sacroiliac joints (SIJ)/spine in inflammatory back pain (IBP) patients suspected of nr-axSpA with high disease... 相似文献
6.
Endoscopic biopsies in Ussing chambers evaluated for studies of macromolecular permeability in the human colon 总被引:6,自引:0,他引:6
Wallon C Braaf Y Wolving M Olaison G Söderholm JD 《Scandinavian journal of gastroenterology》2005,40(5):586-595
OBJECTIVE: Studies of mucosal permeability to protein antigens in humans are limited to in vitro techniques. The use of surgical specimens for such studies has major shortcomings. Endoscopic biopsies in Ussing chambers have been introduced as a means of studying secretion and transepithelial permeability, but have not been evaluated for studies of protein antigen uptake in human intestine. MATERIAL AND METHODS: Standard forceps biopsies from the sigmoid colon of 24 healthy volunteers were mounted in Ussing chambers with an exposed tissue area of 1.76 mm2. 51Cr-EDTA (paracellular probe) and horseradish peroxidase (HRP; 45 kDa protein antigen) were used as permeability markers. Mucosal permeability, electrophysiology, histology and energy contents of the biopsies were studied over time. To evaluate the ability of the technique to detect permeability changes, the mucosa was modulated with capric acid, a medium-chain fatty acid, known to affect tight junctions. RESULTS: In the Ussing chamber the mucosal biopsies were viable for 160 min with stable levels of ATP and lactate, and only minor changes in morphology. Steady-state permeability with low variability was seen for both markers during the 30-90 min period. Exposure to capric acid induced a rapid decrease in short-circuit current (Isc) and a slower reversible decrease in transepithelial resistance (TER), as well as an increased permeability to 51Cr-EDTA and HRP. CONCLUSIONS: Endoscopic biopsies of human colon are viable in Ussing chambers and are reliable tools for studies of mucosal permeability to protein antigens. The technique offers a broad potential for studies of mucosal function in the pathophysiology of human gastrointestinal diseases. 相似文献
7.
Sabriya L. Linton Hannah L.?F. Cooper Mary E. Kelley Conny C. Karnes Zev Ross Mary E. Wolfe Don Des Jarlais Salaam Semaan Barbara Tempalski Elizabeth DiNenno Teresa Finlayson Catlainn Sionean Cyprian Wejnert Gabriela Paz-Bailey for the National HIV Behavioral Surveillance Study Group 《American journal of public health》2015,105(12):2457-2465
Objectives. We explored how variance in HIV infection is distributed across multiple geographical scales among people who inject drugs (PWID) in the United States, overall and within racial/ethnic groups.Methods. People who inject drugs (n = 9077) were recruited via respondent-driven sampling from 19 metropolitan statistical areas (MSAs) for the Centers for Disease Control and Prevention’s 2009 National HIV Behavioral Surveillance system. We used multilevel modeling to determine the percentage of variance in HIV infection explained by zip codes, counties, and MSAs where PWID lived, overall and for specific racial/ethnic groups.Results. Collectively, zip codes, counties, and MSAs explained 29% of variance in HIV infection. Within specific racial/ethnic groups, all 3 scales explained variance in HIV infection among non-Hispanic/Latino White PWID (4.3%, 0.2%, and 7.5%, respectively), MSAs explained variance among Hispanic/Latino PWID (10.1%), and counties explained variance among non-Hispanic/Latino Black PWID (6.9%).Conclusions. Exposure to potential determinants of HIV infection at zip codes, counties, and MSAs may vary for different racial/ethnic groups of PWID, and may reveal opportunities to identify and ameliorate intraracial inequities in exposure to determinants of HIV infection at these geographical scales.Since the mid-1990s, there has been an increase in studies evaluating whether features of the social, economic, physical, and political environment (i.e., place characteristics) affect health. This focus on place characteristics is evident in the development of theories conceptualizing place characteristics as health determinants,1–3 in the use of geospatial and systematic social observation methods to measure place characteristics,4–10 in the application of multilevel modeling to assess the potential impacts of place characteristics,11–18 and in the recognition that interventions should not solely encourage individual behavior change but also modify environmental features.3,16,19Literature emerging from this field of research demonstrates that place characteristics operationalized at different geographical scales influence psychosocial processes and individual behaviors that increase vulnerability to several health outcomes. With rare exception,20–24 however, studies of place and health typically assess the potential influence of place characteristics at a single geographical scale and do not simultaneously evaluate characteristics of other geographical scales. For example, several studies, including our own,25,26 sample participants from a single metropolitan statistical area (MSA) to assess the relationships of census tract characteristics to health, without sampling participants from multiple MSAs to simultaneously assess the relationships of tract-, county-, and MSA-level characteristics to health.25–32 The decision to focus on characteristics of a single geographical scale may arise because of data availability, cost constraints, or feasibility.Studies of place and health that focus on a single geographical scale, however, may misspecify relationships and hinder the exploration of causal pathways in 2 ways. First, studies that focus on features measured at a single geographical scale may overlook potential health determinants that are operationalized at other geographical scales. For instance, research assessing the relationships of features of neighborhoods (e.g., economic deprivation, racial/ethnic composition, policing practices, and “crackdowns”) cannot determine the influence of policies, laws, and governmental expenditures that are operationalized at county, MSA, and state levels, and shape neighborhood environments. Second, studies of features of a single geographical scale cannot determine whether relationships between characteristics operating at one geographical scale are confounded, mediated, or modified by characteristics of other geographic scales.3,16,33 The possibility that at least 1 of these mechanisms can occur has been demonstrated in research conducted by Warner and Gomez, which suggests that, among Black women diagnosed with breast cancer, residing in census blocks with high concentrations of Black residents is more protective against mortality in more racially segregated metropolitan areas than less racially segregated metropolitan areas.34In addition, research assessing the association of place-based factors with health outcomes rarely highlights the extent to which variance in health outcomes is explained by place and place-based factors. Determining whether health outcomes vary geographically can generate hypotheses about inequities in exposure to potential place-based determinants of health, and thereby inform how interventions and social policies are developed and spatially concentrated.35The present study illustrates the generative possibilities of extending research beyond a single geographical scale by achieving 2 primary aims. The study’s first aim is to determine the share of total variance in HIV infection that is apportioned to zip codes, counties, and MSAs among people who inject drugs (PWID). In the United States, PWID account for 22% of people living with HIV,36 and a growing body of literature demonstrates that features of neighborhoods such as census-tract racial composition and block-level social or physical disorder are associated with HIV-related outcomes among PWID,37,38 as are features of MSAs, including drug-related law enforcement, income inequality, residential segregation, and health service access.39–41 Revealing the geographical scale to which variance in HIV infection is apportioned among PWID can stimulate hypotheses about inequities in exposure to place-based determinants of HIV and inform the development and tailoring of place-based interventions. For example, finding high MSA-level variance in HIV infection may support analyses of whether MSA-level variations in health care service access predict variance in HIV serostatus and, if they do, support interventions to increase health care access in low-access MSAs. In contrast, if little to no variance in HIV infection among PWID is apportioned to MSAs, PWID may encounter a relatively uniform exposure to health care service access.Previous studies have found that variance in some health outcomes vary across racial/ethnic groups.42,43 The second aim of this study therefore tests the hypothesis that variance in HIV infection will differ within each of 3 racial/ethnic groups of PWID: non-Hispanic/Latino Whites, non-Hispanic/Latino Blacks, and Hispanics/Latinos. 相似文献
8.
Elio Schouppe Camille Mommer Kiavash Movahedi Damya Laoui Yannick Morias Conny Gysemans Ariane Luyckx Patrick De Baetselier Jo A. Van Ginderachter 《European journal of immunology》2013,43(11):2930-2942
Tumor growth coincides with an accumulation of myeloid‐derived suppressor cells (MDSCs), which exert immune suppression and which consist of two main subpopulations, known as monocytic (MO) CD11b+CD115+Ly6G?Ly6Chigh MDSCs and granulocytic CD11b+CD115?Ly6G+Ly6Cint polymorphonuclear (PMN)‐MDSCs. However, whether these distinct MDSC subsets hamper all aspects of early CD8+ T‐cell activation — including cytokine production, surface marker expression, survival, and cytotoxicity — is currently unclear. Here, employing an in vitro coculture system, we demonstrate that splenic MDSC subsets suppress antigen‐driven CD8+ T‐cell proliferation, but differ in their dependency on IFN‐γ, STAT‐1, IRF‐1, and NO to do so. Moreover, MO‐MDSC and PMN‐MDSCs diminish IL‐2 levels, but only MO‐MDSCs affect IL‐2Rα (CD25) expression and STAT‐5 signaling. Unexpectedly, however, both MDSC populations stimulate IFN‐γ production by CD8+ T cells on a per cell basis, illustrating that some T‐cell activation characteristics are actually stimulated by MDSCs. Conversely, MO‐MDSCs counteract the activation‐induced change in CD44, CD62L, CD162, and granzyme B expression, while promoting CD69 and Fas upregulation. Together, these effects result in an altered CD8+ T‐cell adhesiveness to the extracellular matrix and selectins, sensitivity to FasL‐mediated apoptosis, and cytotoxicity. Hence, MDSCs intricately influence different CD8+ T‐cell activation events in vitro, whereby some parameters are suppressed while others are stimulated. 相似文献
9.
Willem Staels Yannick Verdonck Yves Heremans Gunter Leuckx Sofie De Groef Carlo Heirman Eelco de Koning Conny Gysemans Kris Thielemans Luc Baeyens Harry Heimberg Nico De Leu 《Diabetologia》2018,61(8):1804-1810