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31.
Human colon lipid analysis by imaging mass spectrometry (IMS) demonstrates that the lipid fingerprint is highly sensitive to a cell's pathophysiological state. Along the colon crypt axis, and concomitant to the differentiation process, certain lipid species tightly linked to signaling (phosphatidylinositols and arachidonic acid (AA)-containing diacylglycerophospholipids), change following a rather simple mathematical expression. We extend here our observations to ethanolamine plasmalogens (PlsEtn), a unique type of glycerophospholipid presenting a vinyl ether linkage at sn-1 position. PlsEtn distribution was studied in healthy, adenomatous, and carcinomatous colon mucosa sections by IMS. In epithelium, 75% of PlsEtn changed in a highly regular manner along the crypt axis, in clear contrast with diacyl species (67% of which remained constant). Consistently, AA-containing PlsEtn species were more abundant at the base, where stem cells reside, and decreased while ascending the crypt. In turn, mono?/diunsaturated species experienced the opposite change. These gradients were accompanied by a gradual expression of ether lipid synthesis enzymes. In lamina propria, 90% of stromal PlsEtn remained unchanged despite the high content of AA and the gradient in AA-containing diacylglycerophospholipids. Finally, both lipid and protein gradients were severely affected in polyps and carcinoma. These results link PlsEtn species regulation to cell differentiation for the first time and confirm that diacyl and ether species are differently regulated. Furthermore, they reaffirm the observations on cell lipid fingerprint image sensitivity to predict cell pathophysiological status, reinforcing the translational impact both lipidome and IMS might have in clinical research.  相似文献   
32.
α-Amylase and glucoamylase production by Schwanniomyces castellii   总被引:1,自引:0,他引:1  
A chromogenic substrate (Cibachron blue-amylose), and soluble starch and maltose were used to characterize the amylolytic system from Schwanniomyces castellii 3754. The strain was able to produce inducible -amylase (EC 3.2.1.1) and glucoamylase (EC 3.2.1.3) when grown on different C sources. The effect of the C source was slightly different for -amylase and glucoamylase production. Melezitose, maltose and soluble starch enhanced both -amylase and glucoamylase synthesis to nearly the same extent; amylose, trehalose and cellobiose particularly induced -amylase synthesis. The optimal pH for the release of both amylases was 5.5–7.0; maximal -amylase synthesis, on the other hand, was observed in the medium buffered at pH 6.0. The optimal pH for -amylase and glucoamylase activity was in the range of 4.5–7.2 and 4.2–5.5, respectively. Temperatures allowing maximal activity were 45°C for -amylase and 45–52°C for glucoamylase; a rapid decline of both activities was observed just above these temperatures.The species Schwanniomyces castellii (together with Schw. alluvius) is now considered to be synonymous with Schw. occidentalis var. occidentalis (Kreger-Van Rij 1984).  相似文献   
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Background

Despite being the most common pelvic gynecologic malignancy in industrialized countries, no targeted therapies are available for patients with metastatic endometrial carcinoma. In order to improve treatment, underlying molecular characteristics of primary and metastatic disease must be explored.

Methodology/Principal Findings

We utilized the mass spectrometric-based mutation detection technology OncoMap to define the types and frequency of point somatic mutations in endometrial cancer. 67 primary tumors, 15 metastases corresponding to 7 of the included primary tumors and 11 endometrial cancer cell lines were screened for point mutations in 28 known oncogenes. We found that 27 (40.3%) of 67 primary tumors harbored one or more mutations with no increase in metastatic lesions. FGFR2, KRAS and PIK3CA were consistently the most frequently mutated genes in primary tumors, metastatic lesions and cell lines.

Conclusions/Significance

Our results emphasize the potential for targeting FGFR2, KRAS and PIK3CA mutations in endometrial cancer for development of novel therapeutic strategies.  相似文献   
35.
Three different types of red blood cells (RBC) were used: (i) RBC from sheep having genetically high GSH (ii) RBC from sheep with genetically low GSH and (iii) RBC from high-GSH sheep treated with CDNB to deplete GSH. Incubation of these RBC with t-butyl hydroperoxide (tBHP, 3 mM) for 10 min caused the formation of TBARS, oxidation of haemoglobin and degradation and aggregation of membrane proteins in RBC from low-GSH sheep and GSH-depleted RBC. By contrast, RBC from high-GSH sheep (normal RBC) did not show the degradation and aggregation of membrane proteins within the first 10 min. Dithiothreitol (DTT) was highly effective in preventing the tBHP-mediated oxidation of haemoglobin, the formation of TBARS and the degradation and aggregation of membrane proteins in both normal RBC and low-GSH RBC. However, DTT did not provide protection in GSH-depleted RBC or normal RBCs in the presence of 1.5 mM mercaptosuccinate (MCS), a potent inhibitor of GSH peroxidase (GSHPx). The ability of GSH to prevent the oxidation of haemoglobin and the degradation and aggregation of membrane proteins was abolished in the presence of MCS. These results indicate that the protective function of DTT involves a GSH-dependent mechanism. Both GSH and GSHPx play key roles in this enzymatic system. In the light of the complete protection of RBC against oxidation induced by tBHP in the presence of DTT or GSH, the GSH/GSHPx system appears to act directly as a tBHP scavenger. The activities of four well-known antioxidants, Butylated hydroxytoluene, ascorbate, alpha-tocopherol and desferrioxamine were also tested in this study to cast further light on the role of free radical scavenging in protection from tBHP mediated free radical insult.  相似文献   
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Summary The growth behaviour of Memnoniella echinata and Fusarium roseum was examined in slurry fermentation systems using untreated orange peel as substrate. A composite experiment was then designed to study the effect of orange peel initial concentration and the effect of the nitrogen: peel ratio on crude protein yidld (Y p ) and protein enrichment (Z p ) of the final biomass.The more concentrated the peel slurry, the greater the substrate inhibitory effect on microbial growth becomes.Finally, multiple regression technique allowed both the experimental values of Y p and Z p to be reconstructed with mean percentage errors smaller than 4% and 8%, respectively, and the optimal operating strategy for such SCP production process to be determined.  相似文献   
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A number of studies have established the effects of solar-geomagnetic activity on the human cardio-vascular system. It is plausible that the heliophysical conditions existing during and after hospital admission may affect survival in patients with acute coronary syndromes (ACS). We analyzed data from 1,413 ACS patients who were admitted to the Hospital of Kaunas University of Medicine, Lithuania, and who survived for more than 4 days. We evaluated the associations between active-stormy geomagnetic activity (GMA), solar proton events (SPE), and solar flares (SF) that occurred 0–3 days before and after admission, and 2-year survival, based on Cox’s proportional-hazards model, controlling for clinical data. After adjustment for clinical variables, active-stormy GMA on the 2nd day after admission was associated with an increased (by 1.58 times) hazard ratio (HR) of cardiovascular death (HR?=?1.58, 95 % CI 1.07–2.32). For women, geomagnetic storm (GS) 2 days after SPE occurred 1 day after admission increased the HR by 3.91 times (HR?=?3.91, 95 % CI 1.31–11.7); active-stormy GMA during the 2nd–3rd day after admission increased the HR by over 2.5 times (HR?=?2.66, 95 % CI 1.40–5.03). In patients aged over 70 years, GS occurring 1 day before or 2 days after admission, increased the HR by 2.5 times, compared to quiet days; GS in conjunction with SF on the previous day, nearly tripled the HR (HR?=?3.08, 95 % CI 1.32–7.20). These findings suggest that the heliophysical conditions before or after the admission affect the hazard ratio of lethal outcome; adjusting for clinical variables, these effects were stronger for women and older patients.  相似文献   
40.

Objective

The English questionnaire Pregnancy-Unique Quantification of Emesis and nausea (PUQE) identifies women with severe Hyperemesis Gravidarum. Our aim was to investigate whether scores from the translated Norwegian version; SUKK (SvangerskapsUtløst Kvalme Kvantifisering) was associated with severity of hyperemesis and nutritional intake.

Design

A prospective cohort validation study.

Setting

Hospital cohort of Hyperemesis Gravidarum (HG) patients from western Norway and healthy pregnant women from Bergen, Norway.

Sample

38 women hospitalized due to HG and 31 healthy pregnant controls attending routine antenatal check-up at health centers.

Methods

Data were collected May 2013-January 2014. The study participants answered the Norwegian PUQE-questionnaire (scores ranging from 3 to15) and registered prospectively 24-hours nutritional intake by a food list form.

Main outcome measures

Differences of PUQE-scores, QOL-score and nutritional intake between hyperemesis patients and controls.

Results

Hyperemesis patients had shorter gestational age compared to controls (median 9.7 weeks; 95% CI 8.6-10.6 versus 11.9; 95% CI 10.1-12.9, p=0.004), and larger weight-change from pre-pregnant weight (loss of median 3 kg; 95% CI 3-4 versus gain of 2 kg; 95% CI 0.5-2, p<0.001) otherwise groups were similar regarding pre-pregnant BMI, age, gravidity, and inclusion weight. Compared to controls, hyperemesis patients had significant higher PUQE-score (median 13; 95% CI 11-14 vs. 7; 95% CI 4-8), lower QOL (median score 3; 95% CI 2-4 vs. 6; 95% CI 4.5-8) and lower nutritional intake (energy intake median 990 kcal/24 hours; 95% CI 709-1233 vs. 1652; 95% CI 1558-1880 all p<0.001). PUQE-score was inversely correlated to nutritional intake (-0.5, p<0.001). At discharge PUQE-score had fallen to median 6 (95% CI 5-8) and QOL score risen to 7 (95% CI 6-8) in the HG group, (both p<0.001 compared to admission values).

Conclusion

PUQE-scoring has been validated as a robust indicator of severe hyperemesis gravidarum and insufficient nutritional intake in a Norwegian setting.  相似文献   
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