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131.
D T Bonthron  P Sultan  T Collins 《Genomics》1991,10(1):287-292
The murine proto-oncogene c-sis (Sis, PDGFB), encoding the B chain of platelet-derived growth factor, has been cloned. Its structure, with seven exons spanning approximately 20 kb, closely resembles that of the human and feline homologs. The predicted amino acid sequence of murine PDGF-B has residues 89% identical to those of human PDGF-B. A noncoding region at the start of exon 7, which is deleted by alternative splicing during the generation of the viral v-sis oncogene, is highly conserved in human, mouse, and cat and may represent an important regulatory element.  相似文献   
132.
Summary In a family with a single case of hemophilia A genetic counselling was requested by the pregnant aunt of the propositus. The haplotypes generated by two extra-genic RFLPs, at DXS52 (St14/Taq1) and DXS15 (DX13/BglII), and one intragenic RFLP in F8C (647/BclI) indicated that: (i) she was not a carrier; (ii) the case of hemophilia resulted from a de novo mutation in a grandfather's gamete.  相似文献   
133.
The resurgence of interest in the therapeutic potential of psychedelics for treating psychiatric disorders has rekindled efforts to elucidate their mechanism of action. In this Perspective, we focus on the ability of psychedelics to promote neural plasticity, postulated to be central to their therapeutic activity. We begin with a brief overview of the history and behavioral effects of the classical psychedelics. We then summarize our current understanding of the cellular and subcellular mechanisms underlying these drugs’ behavioral effects, their effects on neural plasticity, and the roles of stress and inflammation in the acute and long-term effects of psychedelics. The signaling pathways activated by psychedelics couple to numerous potential mechanisms for producing long-term structural changes in the brain, a complexity that has barely begun to be disentangled. This complexity is mirrored by that of the neural mechanisms underlying psychiatric disorders and the transformations of consciousness, mood, and behavior that psychedelics promote in health and disease. Thus, beyond changes in the brain, psychedelics catalyze changes in our understanding of the neural basis of psychiatric disorders, as well as consciousness and human behavior.  相似文献   
134.
Antifibrinolytic tranexamic acid (TRX) suppresses plasminogen activation to plasmin in a competitive way. TRX is approved for the management of heavy menstrual periods, hereditary angioedema, hemophilia, postpartum hemorrhage, surgery, tooth extraction, and severe blood loss after acute trauma. Here, the practical use of an isoindole derivative was established for a novel, easy-to-use, and affordable TRX assay. In the presence of a molecule containing a sulfhydryl group (2-mercaptoethanol) 0.02% v/v, the primary amine moiety in TRX allows its combination with o-phthalaldehyde to produce a luminous product. Excitation (338.8 nm) and emission (433.9 nm) wavelengths were used to monitor the isoindole fluorophore yield, and each operational variable was carefully examined and adjusted. The calibration graph was constructed with fluorescence intensity versus TRX concentration, excellent linearity was observed at concentrations between 40 and 950 ng/ml, and limit of detection and limit of quantitation were 41.3 and 13.6 ng/ml, respectively. The International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use guidelines were used to validate the method. The developed method for TRX assay in various dosage forms and urine was successfully implemented and was shown to be an effective, simple, and quick replacement for the TRX assay in clinical trials and quality control.  相似文献   
135.
136.
BackgroundNestin is a neural stem cell protein that plays an important role in cancer stem cells (CSC) development and proliferation. It has been identified as a marker for newly formed endothelial cells and was shown to be preferentially expressed in basal and myoepithelial cells of the mammary gland. HOTAIR is long intergenic non-coding (linRNA) associated with tumorigenesis through promotion of epithelial-mesenchymal transition (EMT) and stemness as well. HOTAIR gene contains a functioning single nucleotide polymorphic site rs12826786 C>T that has been associated with several cancer types.MethodsWe evaluated serum Nestin and the HOTAIR rs12826786 C>T polymorphism in healthy Egyptian women and those with breast cancer as a possible screening tool to identify patients with breast cancer. Also, we tested the possible association of the two markers with each other and the aggressiveness of the disease.ResultsPatients with breast cancer had a median (Min-Max) of serum Nestin 31.3 (6.7-167.3 pg/mL), while control subjects had a median (Min-Max) of serum Nestin 42.3 (25.7-315.95) pg/mL. The best cut-off value for serum Nestin to differentiate normal subjects and patients with breast cancer was 39.9 pg/mL. This cut-off value had a diagnostic sensitivity of 84.8% and specificity of 65.1%. There was a significant difference in the distribution of different alleles in patients with breast cancer than normal subjects (P=0.039 Exact Fisher test). The breast cancer patients group had 23.9% CC, 52.1% CT, and 23.9% TT genotypes, respectively, while the control group had 46.9% CC, 42.8% CT, and 10.2% TT, respectively.ConclusionsA significantly low serum Nestin below 39.9 pg/mL and a higher percentage of the T/T homozygous variant allele of HOTAIR rs12826786 C>T were found in Egyptian patients with breast cancer. We suggest that the reported cut-off value of serum Nestin and the presence of C/T polymorphism can be used to assess the risk of females for developing breast cancer and might be of potential benefit in screening the disease. Larger studies in different ethnic groups are needed to confirm our findings.  相似文献   
137.
Salivary alpha-amylase has been implemented as renewed non-invasive biomarker of interest to measure the levels of stress in humans. In the current clinical study, two-factor repeated-measures cross-sectional design was implemented to determine the salivary alpha-amylase levels and its rhythm characteristics in newly diagnosed female breast cancer in- and out-patients. Alpha-amylase levels were determined using the Salimetrics® salivary alpha-amylase assay kit. Rhythm characteristics of alpha-amylase were computed using the Cosinor Rhythmometry technique. Results showed that the levels of alpha-amylase significantly increased from/to the increasing number of chemotherapy cycle in patients of both group; however the levels were higher in in-patients. Further, results revealed significant differences in rhythm characteristics of alpha-amylase characterized by higher MESOR, lower amplitude, and advanced acrophase in in-patients as compared to out-patients. Current findings indicate that patients of both the groups were associated with progression under stress levels across the number of chemotherapy cycle; however, the levels of stress were higher in in-patients as compared to out-patients. Higher level of stress in cancer in-patients could be attributed to the possible effect of hospitalization and/or relative social isolation.  相似文献   
138.

Morning and evening-type individuals differ on a number of psychological and biological variables. In this study, we aimed to investigate the relationship between sleep quality, dream anxiety, and chronotypes. A sample of 264 university students, aged between 17 and 26 years, completed the Morningness-Eveningness Questionnaire, the Pittsburgh Sleep Quality Index, and the Van Dream Anxiety Scale for assessing nightmare frequency and the dream anxiety caused by frightening dreams. Main findings indicated that evening-type individuals were significantly more likely to suffer from poor sleep quality, daytime dysfunction, nightmares, and nightmare-related disturbances as compared to either intermediate- or morning-type individuals. Previous studies have pointed out the possible connections of irregular sleep-wake habits and circadian dysregulation with a tendency to reveal eveningness chronotypical characteristics. Current findings suggest that evening-type individuals are more prone to experience psychologically deteriorating nightmares and sleep-related anxiety. Poor sleep quality is also a significant antecedent of dream anxiety after controlling for age and gender.

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139.
Three phenylalanine-negative Proteus vulgaris strains were isolated from three different sources. The significance of these Proteus strains has not been fully recognized.  相似文献   
140.

Background

Recent linkage between primary and secondary care data has provided valuable information for studying heath outcomes that may initially present in different health care settings. The aim of this study was therefore, twofold: to use linked primary and secondary care data to determine an optimum definition for estimating the incidence of first VTE in and around pregnancy; and secondly to conduct a systematic literature review of studies on perinatal VTE incidence with the purpose of comparing our estimates.

Methods

We used primary care data from the Clinical Practice Research Datalink (CPRD), which incorporates linkages to secondary care contained within Hospital Episode Statistics (HES) between 1997 and 2010 to estimate the incidence rate of VTE in the antepartum and postpartum period. We systematically searched the literature on the incidence of VTE during antepartum and postpartum periods and performed a meta-analysis to provide comparison.

Findings

Using combined CPRD and HES data and a restrictive VTE definition, the absolute rate during the antepartum period and first six weeks postpartum (early postpartum) were 99 (95%CI 85–116) and 468 (95%CI 391–561) per 100,000 person-years respectively. These were comparable to the pooled estimates from our meta-analysis (using studies after 2005) during the antepartum period (118/100,000 person-years) and early postpartum (424/100,000 person-years). When we used only secondary care data to identify VTE events, incidence was lower during the early postpartum period (308/100,000 person-years), whereas relying only on primary care data lead to lower incidence during the time around delivery, but higher rates during the postpartum period (558/100,000 person-years).

Conclusion

Using combined CPRD and HES data gives estimates of the risk of VTE in and around pregnancy that are comparable to the existing literature. It also provides more accurate estimation of the date of VTE diagnosis which will allow risk stratification during specific pregnancy and postpartum periods.  相似文献   
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