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Nitric oxide (NO) production and carbon monoxide (CO) production are increased in inflammatory lung diseases. Although there are some pieces of evidence for hormonal modulation by estrogen, little is known about exhaled NO and CO during the ovarian cycle. In 23 subjects, we measured exhaled NO and CO by an online analyzer. Significantly higher levels of exhaled NO were found at the midcycle compared with those in the premenstrual period or during menstruation. Higher levels of CO were after ovulation and reached a peak in the premenstrual phase. The lowest levels of CO were observed in the first days of the estrogen phase. In males, there was no significant variation in exhaled NO and CO. Exhaled NO and CO levels vary during the ovarian cycle in women, and this fact should be taken into account during serial measurements of these markers in the female population.  相似文献   
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The purpose of this study is to evaluate the relationship between the concentration of interleukin-8 (IL-8) in exhaled breath condensate (EBC) and bronchoalveolar lavage fluid (BALF) with the disease activity score and pulmonary function of systemic lupus erythematosus (SLE) patients with and without pulmonary fibrosis. Thirty-four SLE patients and 31 healthy controls were enrolled and evaluated using high-resolution computed tomography (HRCT), pulmonary function tests, systemic lupus activity measure (SLAM), assessing BALF and EBC. IL-8 levels in BALF and EBC samples were measured with an enzyme-immunosorbent assay kit. The mean (±SEM) IL-8 concentrations in BALF and EBC were higher in SLE patients compared to healthy controls (34.84 ± 95.0 vs. 7.65 ± 21.22 pg/ml, p < 0.001; 3.82 ± 0.52 pg/m vs. 1.7 ± 1.7 pg/ml, p < 0.001, respectively). SLE patients had increased percentage of neutrophils in BALF when compared with control group (1.00 ± 5.99 vs. 0.00 ± 0.56 %, p = 0.0003). Pulmonary fibrosis in HRCT was found in 50 % of SLE patients. The disease activity scored by SLAM was significantly higher and total lung capacity was significantly lower in SLE patients with pulmonary fibrosis (8.00 ± 3.17 vs. 6.00 ± 2.31, p = 0.01; 88.00 ± 28.29 vs. 112.00 ± 21.08 % predicted, p = 0.01, respectively). In SLE patients with pulmonary fibrosis, correlations were found between SLAM and IL-8 concentration in BALF, forced expiratory volume in 1 s and forced vital capacity (r = 0.65, p = 0.006; r = ?0.53, p = 0.035; r = ?0.67, p = 0.006, respectively). Our results indicate that IL-8 plays an important role in the pathogenesis of SLE. An increased concentration of IL-8 according to BALF could be considered as a useful biomarker of SLE activity and pulmonary fibrosis in SLE.  相似文献   
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The histone chaperone Rtt106 binds histone H3 acetylated at lysine 56 (H3K56ac) and facilitates nucleosome assembly during several molecular processes. Both the structural basis of this modification-specific recognition and how this recognition informs Rtt106 function are presently unclear. Guided by our crystal structure of Rtt106, we identified two regions on its double-pleckstrin homology domain architecture that mediated histone binding. When histone binding was compromised, Rtt106 localized properly to chromatin but failed to deliver H3K56ac, leading to replication and silencing defects. By mutating analogous regions in the structurally homologous chromatin-reorganizer Pob3, we revealed a conserved histone-binding function for a basic patch found on both proteins. In contrast, a loop connecting two β-strands was required for histone binding by Rtt106 but was dispensable for Pob3 function. Unlike Rtt106, Pob3 histone binding was modification-independent, implicating the loop of Rtt106 in H3K56ac-specific recognition in vivo. Our studies described the structural origins of Rtt106 function, identified a conserved histone-binding surface, and defined a critical role for Rtt106:H3K56ac-binding specificity in silencing and replication-coupled nucleosome turnover.  相似文献   
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A theoretical model using a decision tree is used to compare three alternative strategies: extract all third molars prior to complete root formation; extract only those third molars that become impacted; and extract only those impacted third molars that develop some associated pathology. The model used to determine the expected value of these alternative strategies depends on the probability of eruption, the type of impaction, and likelihood of developing preoperative pathology. The decision tree can be used to identify a preferred strategy either for an individual patient or for a policy recommendation under a variety of clinical conditions.  相似文献   
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The increase in intracellular free calcium concentration is an important step in signal transduction leading to phagocyte activation. The undecapeptide substance P can influence various functions of human polymorphonuclear leukocytes, including chemotaxis, phagocytosis, and respiratory burst. In this study we investigated the ability of low-concentration (that can occur in vivo) substance P (10−7 M) and its precursor α-protachykinin (3×10−7 M) to increase the intracellular free calcium concentration in human polymorphonuclear leukocytes. Cells isolated from ten healthy donors were incubated with substance P or α-protachykinin in 1 mM calcium medium for 5 min and the intracellular free calcium concentration was monitored using the fluorescent calcium indicator Fura-2am. Polymorphonuclear leukocytes from 40% of donors responded to both agonists. The substance P- and α-protachykinin-induced increase in intracellular free calcium concentration was 59±13 nM and 58±12 nM and the extracellular calcium influx contributed to 87±8% and 54±8% of the calcium response, respectively. α-Protachykinin released almost all the calcium from intracellular stores, while substance P mobilized only 24±5% of this calcium pool. Finally, cells that responded to a single challenge with substance P and α-protachykinin were able to increase their intracellular free calcium concentration in response to each of three consecutive stimulations with these agonists. This may be an additional mechanism by which substance P and its precursor modify the function of human polymorphonuclear leukocytes.  相似文献   
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Immortalized cell lines have many potential experimental applications including the analysis of molecular mechanisms underlying cell-specific gene expression. We have utilized a recombinant retrovirus encoding the simian virus-40 (SV-40) large T antigen to construct several immortalized cell lines of equine chorionic girdle cell lineage - the progenitor cells that differentiate into the equine chorionic gonadotropin (eCG) producing endometrial cups. Morphologically, the immortalized cell lines appear similar to normal chorionic girdle cells. Derivation of the immortalized cell lines from a chorionic girdle cell lineage was verified by immunological detection of cell-surface antigens specific to equine invasive trophoblasts. The cell lines differed, however, from mature chorionic girdle cells or endometrial cup cells in that they did not produce eCG and did express MHC class I molecules. Thus, these cell lines appear to have been arrested at a stage of development prior to final differentiation into endometrial cup cells. It was also determined that some of these cell lines as well as endometrial cups express the estrogen receptor-related receptor beta gene, but not the glial cell missing gene (GCMa) both of which are expressed in the murine and human placenta. Among these cell lines, three (eCG 50.5, 100.6 and 500.1) express eCG alpha mRNA. Since regulation of eCG alpha subunit gene is largely unknown, we investigated the signal transduction pathways regulating the eCG alpha subunit gene. Both activators of protein kinase A (PKA) and protein kinase C (PKC) induced the expression of eCG alpha subunit expression 3.2 (P<0.05)- and 1.9 (P<0.05)-fold respectively, in the eCG 500.1 cell line. However, activation of these pathways failed to induce eCG beta subunit expression. In conclusion, lines of equine trophoblast cells have been immortalized that display markers characteristic of those with the equine chorionic girdle and endometrial cup cell lineage. A subset of these cells expresses the eCG alpha subunit gene which is responsive to activators of the PKA and PKC signal transduction pathways.  相似文献   
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BACKGROUND: Sputum induction is increasingly used to study both cellular and biochemical composition of the airways. However, there is a significant rise in the percentage of neutrophils at 8 h after inhalation with hypertonic saline. OBJECTIVE: The aim of this study was to assess whether markers of inflammation in exhaled air and exhaled air condensate change after sputum induction in normal and asthmatic subjects. METHODS: We measured leukotriene B(4) (LTB(4)) and a marker of oxidative stress, 8-isoprostane, (by enzyme immunoassay) in exhaled air condensate and exhaled nitric oxide (NO; by chemiluminescence analyzer) in 15 healthy subjects (8 females, mean age 35 +/- 4 years, FEV(1) 97.4% predicted) and in 8 mild asthmatic subjects (5 males, mean age 34 +/- 2 years, FEV(1) 70.5% predicted). RESULTS: LTB(4) was significantly higher compared with baseline at 6 h but did not remain increased at 24 h after sputum induction (134.3 +/- 30.15 and 75.4 +/- 14.32 vs. 64.6 +/- 11.6 pg/ml at baseline; p < 0.02 and p > 0.05, respectively) in healthy subjects. An inverse correlation between LTB(4) and exhaled NO at 6 h after sputum induction was observed in healthy subjects (r = -0.66, p < 0.03). No increase in LTB(4) levels was observed in asthmatic patients. Baseline 8-isoprostane levels were higher in asthmatic patients than in healthy subjects (47.3 +/- 37.1 vs. 17.5 +/- 8.8 pg/ml; p < 0.01). A trend towards increased levels of 8-isoprostane could be observed at 6 and 24 h after inhalation in healthy subjects (26.2 +/- 3.7 and 26.7 +/- 3.9 pg/ml; p = 0.09 and p = 0.07, respectively). In healthy subjects, exhaled NO was significantly higher compared with baseline at 6 h and remained increased 24 h after sputum induction (7.96 +/- 3.5 vs. 5.61 +/- 1.86 ppb; p < 0.01 and p < 0.05, respectively). Exhaled NO levels were increased in asthmatic patients but did not further increase after sputum induction. CONCLUSIONS: Sputum induction with hypertonic saline causes an inflammatory response which should be considered when using the technique to monitor airway inflammation.  相似文献   
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