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51.
Elina MS Paaso Maritta S Jaakkola Aino K Rantala Timo T Hugg Jouni JK Jaakkola 《Respiratory research》2014,15(1)
BackgroundFamily history of asthma and other allergic diseases have been linked to the risk of childhood asthma previously, but little is known about their effect on the age-of-onset and persistency of asthma until young adulthood.MethodsWe assessed the effect of the family history of asthma and allergic diseases on persistent vs. transient, and early- vs. late-onset persistent asthma in The Espoo Cohort Study 1991–2011, a population-based cohort study of 1623 subjects (follow-up rate 63.2%). The determinants were any family history (any parent or sibling); maternal; paternal; siblings only; parents only; and both siblings and parents. Analyses were conducted separately for asthma and allergic diseases while taking the other disease into account as a confounding factor. The outcomes were persistent, transient, early-onset persistent (<13 years) and late-onset persistent asthma. Adjusted risk ratios (RR) were calculated applying Poisson regression. Q-statistics were used to assess heterogeneity between RRs.ResultsFamily history was associated with the different subtypes but the magnitude of effect varied quantitatively. Any family history of asthma was a stronger determinant of persistent (adjusted RR = 2.82, 95% CI 1.99-4.00) than transient asthma (1.65, 1.03-2.65) (heterogeneity: P = 0.07) and on early-onset than late-onset persistent asthma. Also any family history of allergic diseases was a stronger determinant of persistent and early-onset asthma. The impact of paternal asthma continued to young adulthood (early-onset: 3.33, 1.57-7.06 vs. late-onset 2.04, 0.75-5.52) while the influence of maternal asthma decreased with age (Early-onset 3.94, 2.11-7.36 vs. Late-onset 0.88, 0.28-2.81). Paternal allergic diseases did not follow the pattern of paternal asthma, since they showed no association with late-onset asthma. Also the effect estimates for other subtypes were lower than in other hereditary groups (persistent 1.29, 0.75-2.22 vs. transient 1.20, 0.67-2.15 and early-onset 1.86, 0.95-3.64 vs. late-onset 0.64, 0.22-1.80).ConclusionsFamily history of asthma and allergic diseases are strong determinants of asthma, but the magnitude of effect varies according to the hereditary group so that some subtypes have a stronger hereditary component, and others may be more strongly related to environmental exposures. Our results provide useful information for assessing the prognosis of asthma based on a thorough family history. 相似文献
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54.
Flierl MA Rittirsch D Huber-Lang M Sarma JV Ward PA 《Molecular medicine (Cambridge, Mass.)》2008,14(3-4):195-204
It is well established that catecholamines (CAs), which regulate immune and inflammatory responses, derive from the adrenal medulla and from presynaptic neurons. Recent studies reveal that T cells also can synthesize and release catecholamines which then can regulate T cell function. We have shown recently that macrophages and neutrophils, when stimulated, can generate and release catecholamines de novo which, then, in an autocrine/paracrine manner, regulate mediator release from these phagocytes via engagement of adrenergic receptors. Moreover, regulation of catecholamine-generating enzymes as well as degrading enzymes clearly alter the inflammatory response of phagocytes, such as the release of proinflammatory mediators. Accordingly, it appears that phagocytic cells and lymphocytes may represent a major, newly recognized source of catecholamines that regulate inflammatory responses. 相似文献
55.
Schreiner L Huber-Lang M Weiss ME Hohmann H Schmolz M Schneider EM 《Journal of cell communication and signaling》2011,5(2):135-144
The function of phagocytic and antigen presenting cells is of crucial importance to sustain immune competence against infectious
agents as well as malignancies. We here describe a reproducible procedure for the quantification of phagocytosis by leukocytes
in whole blood. For this, a pH-sensitive green-fluorescent protein- (GFP) like dye (Eos-FP) is transfected into infectious
microroganisms. After UV-irradiation, the transfected bacteria emit green (≈5160 nm) and red (≈581 nm) fluorescent light at
490 nm excitation. Since the red fluorescent light is sensitive to acidic pH, the phagocytosed bacteria stop emitting red
fluorescent light as soon as the phagosomes fuse with lysosomes. The green fluorescence is maintained in the phagolysosome
until pathogen degradation is completed. Fluorescence emission can be followed by flow cytometry with filter settings documenting
fluorescence 1 (FL 1, FITC) and fluorescence 2 (FL 2, phycoerythrin, PE). Eos-FP transfected bacteria can also be traced within
phagocytes using microscopical techniques. A standardized assay has been developed which is suitable for clinical studies
by providing clinicians with syringes pre-filled with fixed and appropriately UV-irradiated Eos-FP E. coli (TruCulture™).
After adding blood or body fluids to these containers and starting the incubation at 37°C, phagocytosis by granulocytes proceeds
over time. Cultures can be terminated at a given time by lysing red blood cells followed by flow cytometry. A pilot study
demonstrated that Eos-FP E. coli phagocytosis and digestion was up-regulated in the majority of patients with either severe
sepsis or septic shock as compared to healthy donors (p < 0.0001 after o/n incubation). Following treatment with recombinant human granulocyte colony-stimulating factor (rhG-CSF)
in selected patients with sepsis, phagolysosome fusion appeared to be accelerated. 相似文献
56.
Lazos-Monterrosa FA C Orantes-García O Farrera-Sarmiento AG Verdugo-Valdez MS Sánchez-Cortés LE Ruíz-Meza 《Phyton》2015,84(1):138-143
The tempisque (Sideroxylon capiri) is a tree native to Mexico used by the rural population for housing construction, poles and hedges, as fuel (wood) and also for fodder and ornamental purposes, among others. It is considered an endangered species. In order to contribute to its preservation and sustainable management, it was considered important to determine the proportion of viable seeds, the loss of viability due to storage period and the germination process by applying pregerminative treatments. We found that freshly collected seeds showed 100% viability, which decreased to 0% after 5 months of storage. According to the cumulative germination significant differences between treatments (p≤0.01) were found. It was observed that seeds can accelerate their time of germination with the previous exposure of 24 h in water at room temperature. The soaking treatment in water for 24 h at room temperature obtained final germination of 55%, while with the control 39% was reached. Soaking in hydrogen peroxide and scarification were the treatments with lower germination percentage (33 and 23%, respectively). To get a higher percentage of germinated seeds in a short time, it is necessary to give a soaking treatment in water for 24 h before sowing. 相似文献
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58.
Raynner RD Barboza Wedson de MS Souto José da S Mourão 《Journal of ethnobiology and ethnomedicine》2007,3(1):1-14
Background
Viewed through the micro focus of an interpretive lens, medical anthropology remains mystified because interpretivist explanations seriously downplay the given context in which individual health seeking-behaviours occur. This paper draws upon both the interpretivist and political economy perspectives to reflect on the ethno medical practices within the Korean-Australian community in Sydney.Methods
We draw on research data collected between 1995 and 1997 for an earlier study of the use of biomedical and traditional medicine by Korean-Australians in Sydney. A total of 120 interviews were conducted with a range of participants, including biomedical doctors, traditional health professionals, Korean community leaders and Korean migrants representing a range of socio-economic backgrounds and migration patterns.Results and Discussion
First, the paper highlights the extent to which the social location of migrants in a host society alters or restructures their initial cultural practices they bring with them. Second, taking hanbang medicine in the Korean-Australian community as an illustrative case, the paper explores the transformation of the dominant biomedicine in Australia as a result of the influx of ethnomedicine in the era of global capitalism and global movement.Conclusion
In seeking to explain the popularity and supply of alternative health care, it is important to go beyond the culture of each kind of health care itself and to take into consideration the changes occurring at societal, national and global levels as well as consequential individual response to the changes. New social conditions influence the choice of health care methods, including herbal/alternative medicine, health foods and what are often called New Age therapies. 相似文献59.
Differentiation-associated modulation of heparan sulfate structure and function in CaCo-2 colon carcinoma cells 总被引:1,自引:2,他引:1
Salmivirta M; Safaiyan F; Prydz K; Andresen MS; Aryan M; Kolset SO 《Glycobiology》1998,8(10):1029-1036
Heparan sulfate species expressed by different cell and tissue types differ
in their structural and functional properties. Limited information is
available on differences in regulation of heparan sulfate biosynthesis
within a single tissue or cell population under different conditions. We
have approached this question by studying the effect of cell
differentiation on the biosynthesis and function of heparan sulfate in
human colon carcinoma cells (CaCo-2). These cells undergo spontaneous
differentiation in culture when grown on semipermeable supports; the
differentiated cells show phenotypic similarity to small intestine
enterocytes. Metabolically labeled heparan sulfate was isolated from the
apical and basolateral media from cultures of differentiated and
undifferentiated cells. Compositional analysis of disaccharides, derived
from the contiguous N-sulfated regions of heparan sulfate, indicated a
greater proportion of 2-O- sulfated iduronic acid units and a smaller
amount of 6-O-sulfated glucosamine units in differentiated than in
undifferentiated cells. By contrast, the overall degree of sulfation, the
chain length and the size distribution of the N-acetylated regions were
similar regardless the differentiation status of the cells. The structural
changes were found to affect the binding of heparan sulfate to the long
isoform of platelet-derived growth factor A chain but not to fibroblast
growth factor 2. These findings show that heparan sulfate structures change
during cell differentiation and that heparan sulfate-growth factor
interactions may be affected by such changes.
相似文献
60.
Kajsa Sjöholm Björn Carlsson Lena MS Carlsson 《Central European Journal of Biology》2006,1(2):221-234
The leptin system regulates body fat mass through a feedback loop between adipose tissue and the hypothalamus. To test if
leptin responsiveness may be regulated we assayed hypothalamic response to leptin during the estrous cycle; when changes in
food intake are known to occur. Immature rats were treated with pregnant mare’s serum gonadotropin (PMSG) to induce synchronized
follicular development, ovulation and corpus luteum formation. Leptin response was estimated by measuring the in vitro induction of tis11, a primary response gene activated by STAT3-dependent cytokines in hypothalamic explants after leptin stimulation. In addition,
mRNA levels of the suppressor cytokine signaling-3 (SOCS-3), a possible mediator of leptin resistance, were analyzed. Serum
leptin levels did not change between days 2 and day 3 (corresponding to proestrus and estrus, respectively) but the response
to leptin was higher on day 2 than on day 3 (p=0.05). Food intake displayed a tendency towards downregulation between day
1 and day 2 (p=0.057), and a tendency towards upregulation between day 2 and day 3 (p=0.072), although the body weight increased
on day of the study (p<0.0001). There was no significant difference in hypothalamic expression of SOCS-3 between day 2 and
day 3. In conclusion, we have shown that leptin responsiveness changes during a hormonally induced estrous cycle in rats.
Our data suggest that a change in the hypothalamic response to leptin may cause the cyclic feeding behavior seen in rats. 相似文献