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51.

In Turkey, all heavy-vehicle driver’s license applicants older than 45 years and with body mass index (BMI) >25 kg/m2 are required to have polysomnography (PSG). However, this law is usually overlooked in practice due to the large number of applications. We aimed to assess the usefulness of four standardized questionnaires: Berlin, STOP, STOP-BANG and OSA50, in identifying the high-risk bus drivers for obstructive sleep apnea (OSA). Ninety highway bus drivers underwent polysomnography and completed four questionnaires. They also underwent otolaryngologic evaluation and blood testing for probable co-existing conditions such as diabetes and hypothyroidism. Neck circumference, BMI, waist circumference, prevalence of OSA and metabolic syndrome, oxygen desaturation index and duration of sleep associated with less than 90% saturation were significantly higher and mean oxygen saturation was significantly lower in drivers >45 years old than drivers <45 years old. STOP-BANG questionnaire had the highest sensitivity (87%) and the highest negative predictive value (NPV) (76%) in identifying high-risk for OSA. A cut off of 45 years old is suitable in screening highway bus drivers for OSA. Among the four questionnaires, STOP-BANG questionnaire had the highest sensitivity and negative predictive value (NPV) in identifying high risk patients for OSA in highway bus drivers and can be safely used as a screening test in this group.

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52.
In this study, a survey of miRNAs using the next-generation sequencing data was performed at subgenomic level. After analyzing shotgun sequences from chromosome 4A of bread wheat (Triticum aestivum L.), a total of 68 different miRNAs were predicted in silico, of which 37 were identified in wheat for the first time. The long arm of the chromosome was found to harbor a higher variety (51) and representation (3,928) of miRNAs compared with the short arm (49; 2,226). Out of the 68 miRNAs, 32 were detected to be common to both arms, revealing the presence of separate miRNA clusters in the two chromosome arms. The differences in degree of representation of the different miRNAs were found to be highly variable, ranging 592-fold, which may have an effect on target regulation. Targets were retrieved for 62 (out of 68) of wheat-specific, newly identified miRNAs indicated that fundamental aspects of plant morphology such as height and flowering were predicted to be affected. In silico expression blast analysis indicated 24 (out of 68) were found to give hits to expressed sequences. This is the first report of species- and chromosome-specific miRNAs.  相似文献   
53.
54.
Bone marrow mesenchymal stem cells (BM‐MSCs) are promising candidates for regenerative medicine purposes. The effect of obesity on the function of BM‐MSCs is currently unknown. Here, we assessed how obesity affects the function of BM‐MSCs and the role of endoplasmic reticulum (ER) stress and the unfolded protein response (UPR) therein. BM‐MSCs were obtained from healthy donors with a normal (<25) or high (>30) body mass index (BMI). High‐BMI BM‐MSCs displayed severely impaired osteogenic and diminished adipogenic differentiation, decreased proliferation rates, increased senescence, and elevated expression of ER stress–related genes ATF4 and CHOP. Suppression of ER stress using tauroursodeoxycholic acid (TUDCA) and 4‐phenylbutyrate (4‐PBA) resulted in partial recovery of osteogenic differentiation capacity, with a significant increase in the expression of ALPL and improvement in the UPR. These data indicate that BMI is important during the selection of BM‐MSC donors for regenerative medicine purposes and that application of high‐BMI BM‐MSCs with TUDCA or 4‐PBA may improve stem cell function. However, whether this improvement can be translated into an in vivo clinical advantage remains to be assessed.  相似文献   
55.
In the present work, we provide compelling evidence for the expression of a ghrelin-like peptide hormone that has only been associated with animals, in various plant tissues. Ghrelin, the appetite stimulating hormone, has been identified from a number of different species including humans, rat, pig, mouse, gerbil, eel, goldfish, bullfrog and chicken. The study here was conducted using an immunohistochemistry assay to screen whether plants have any ghrelin immunoreactivity. In this respect, Prunus x domestica L. and Marus alba were examined. Immunohistochemistry results showed that there is a strong human ghrelin immunoreactivity substance in the parenchyma cells of these plants. This was entirely unexpected since this hormone was considered to be present solely in animals. Thus, this study is the first to report the presence of a peptide with ghrelin-like activity in plants, a finding that has only been observed in the animal kingdom. RIA analysis confirmed that these plants contain significant amounts of this substance. Furthermore, reverse-phase HPLC analyses of plant extracts showed an elution characteristic of the peptide identical to that of human ghrelin. In general, fruit from both plants had higher levels of the peptide than the vegetative parts.  相似文献   
56.
Current knowledge of resistance (R) genes and their use for genetic improvement in buffalograss (Buchloe dactyloides [Nutt.] Engelm.) lag behind most crop plants. This study was conducted to clone and characterize cDNA encoding R gene-like (RGL) sequences in buffalograss. This report is the first to clone and characterize of buffalograss RGLs. Degenerate primers designed from the conserved motifs of known R genes were used to amplify RGLs and fragments of expected size were isolated and cloned. Sequence analysis of cDNA clones and analysis of putative translation products revealed that most encoded amino acid sequences shared the similar conserved motifs found in the cloned plant disease resistance genes PRS2, MLA6, L6, RPMI, and Xa1. These results indicated diversity of the R gene candidate sequences in buffalograss. Analysis of 5′ rapid amplification of cDNA ends (RACE), applied to investigate upstream of RGLs, indicated that regulatory sequences such as TATA box were conserved among the RGLs identified. The cloned RGL in this study will further enhance our knowledge on organization, function, and evolution of R gene family in buffalo grass. With the sequences of the primers and sizes of the markers provided, these RGL markers are readily available for use in a genomics-assisted selection in buffalograss.  相似文献   
57.
Background: A common G to A polymorphism (G870A) in the splice donor region of exon 4 of cyclin D1 (CCND1) gene generates two mRNAs (cyclin D1a and D1b) through an alternative splicing at the site of this polymorphism. Cyclin D1a and b proteins differ in their COOH-terminus, a region involved in protein degradation. We examined the association between this CCDN1 genotype and the susceptibility to hepatocellular carcinoma (HCC) in a Turkish population. Methods: The genotype frequency of this polymorphism was determined by using a polymerase chain reaction–restriction fragment length polymorphism (PCR–RFLP) assay. Hospital-based case–control study was designed consisting of 160 diagnosis subjects with hepatocellular carcinoma and 160 cancer-free control subjects matched on age, gender, smoking and alcohol status. Results: The allele frequencies of case subjects (A, 0.55; G, 0.45) were significantly different from those of control subjects (A, 0.42; G, 0.58) (p = 0.002). The odds ratios (ORs) for the CCND1 870 GA and AA genotypes when compared with the GG genotypes were 1.39 (95% confidence interval [CI] 0.82–2.36, p = 0.22) and 2.52 (95% CI 1.38–4.62, p = 0.003) respectively. The presence of at least one CCND1 870A allele was associated with increased risk for HCC (OR, 1.73; 95% CI, 1.06–2.82, p = 0.03). When combining the GG and GA genotypes as a reference genotype, we found that the OR for the AA genotype was 2.06 (95% CI 1.24–3.44, p = 0.006). Conclusion: Our results suggest that the CCND1 G870A single nucleotide polymorphism is associated with an increased risk of HCC in our Turkish population.  相似文献   
58.
Cyclooxygenase-2 (COX-2) influences carcinogenesis through immune response suppression, apoptosis inhibition, regulation of angiogenesis and tumor cell invasion, and metastasis. It is now well established that COX-2 is overexpressed in many premalignant, malignant, and metastatic cancers, including hepatocellular carcinoma (HCC). DNA sequence variations in the COX-2 gene may lead to altered COX-2 production and/or activity, and so they cause inter-individual differences in the susceptibility to HCC. Functional coding region polymorphisms -1195A>G (rs689466), -765G>C (rs20417), and +8473T>C (rs5275) in the COX-2 gene have recently been shown to be associated with several human cancers but their association with HCC has yet to be investigated. We used hospital-based case-control study to assess the hypothesis that the functional COX-2 variation may affect individual susceptibility to the HCC. COX-2 polymorphisms were investigated in 129 confirmed subjects with HCC and 129 cancer-free control subjects matched on age, gender, smoking, and alcohol consumption using a polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay. The distribution of the COX-2 -1195A>G and +8473T>C genotypes were not significantly different between HCC cases and control. However, proportion of the COX-2 -765CC genotype which leads to a 30% reduction of the COX-2 promoter activity was significantly lower in patients with HCC (3.1%) when compared to control subjects (11.6%) (P < 0.05). Logistic regression analyses revealed that the COX-2 -765G>C variant genotype (-765CC) was associated with a significantly decreased risk of HCC compared with the -765GG wild-type homozygotes [P < 0.05, odds ratio (OR) = 0.25, 95% confidence interval (CI) = 0.08-0.79]. Our results suggest for the first time that the -765CC genotype of COX-2 -765G>C polymorphism, causing lower COX-2 gen expression, is a genetic protective factor for HCC. However, because this is the first report concerning the COX-2 -1195A>G, -765G>C, and +8473T>C polymorphisms and the risk of HCC, independent studies are needed to validate our findings.  相似文献   
59.
Functional & Integrative Genomics - Beyond the most crucial roles of RNA molecules as a messenger, ribosomal, and transfer RNAs, the regulatory role of many non-coding RNAs (ncRNAs) in plant...  相似文献   
60.

Aim

The programmed cell death-1 (PD-1) is a potent immunoregulatory molecule which is responsible for the negative regulation of T-cell activation and peripheral tolerance. Recently, overexpression of PD-1 has been reported to contribute to immune system evasion and poor survival of hepatocellular carcinoma (HCC). A common single nucleotide polymorphism in intron 4 of PD-1 gene called PD-1.3 has been reported to influence PD-1 expression, but its association with HCC has yet to be investigated. The aim of the present study was to investigate whether this polymorphism could be involved in the risk of HCC susceptibility.

Methods

The genotype frequency of PD-1.3 polymorphism was determined by using a polymerase chain reaction–restriction fragment length polymorphism (PCR–RFLP) method in 236 subjects with HCC and 236 cancer-free control subjects matched on age, gender, smoking and alcohol status.

Results

No statistically significant differences were found in the genotype distributions of the PD-1.3 polymorphism among HCC and cancer-free control subjects (P = 0.22).

Conclusion

Our results demonstrate for the first time that the PD-1.3 polymorphism has not been in any major role in genetic susceptibility to hepatocellular carcinogenesis, at least in the population studied here. Independent studies are needed to validate our findings in a larger series, as well as in patients of different ethnic origins.  相似文献   
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