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61.
Objective: To examine the relationship between maternal hemoglobin concentration (Hb) at 2729 weeks’ gestation and severity of pre-eclampsia (PE).

Methods: This was a retrospective study of maternal Hb at 2729 week in 497 pregnancies that developed PE and 497 healthy controls with normal pregnancy outcomes. Multiple regression analysis was used to examine the association between HB and maternal characteristics and severity of PE classified according to gestation at delivery, birth weight and prevalence of abnormal peripartum maternal creatinine, aspartate transaminase and platelet count.

Results: There was no significant difference in median Hb between the PE and control groups. Multiple regression analysis in the PE group showed that significant prediction for Hb was provided by Afro-Caribbean race, gestation at delivery, maternal platelet count <2.5th percentile and birth weight, but not serum creatinine or aspartate transaminase above the 97.5th percentile. Increased Hb was observed in both small and large for gestational age neonates.

Conclusion: In PE, Hb at 27–29 weeks is influenced by birth weight, maternal characteristics and platelet count.  相似文献   

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Intact phase II steroid metabolites have poor product ion mass spectra under collision-induced dissociation (CID) conditions. Therefore, we present herein the liquid chromatography–electrospray ionization–tandem mass spectrometry (LC–ESI–MS/(MS)) behavior of intact phase II metabolites of oxosteroids after derivatization. Based on the fact that Girard's reagent T (GRT), as derivatization reagent, was both convenient and efficient in terms of the enhancement in the ionization efficiency and the production of diagnostic product ions related to the steroid moiety, the latter was preferably selected between methoxamine and hydroxylamine upon the model compounds of androsterone glucuronide and androsterone sulfate. Sixteen different glucuronides and 29 sulfate conjugated metabolites of anabolic androgenic steroids (AASs), available either as pure reference materials or synthesized/extracted from administration studies, were derivatized with GRT, and their product ion spectra are presented. Product ion spectra include in all cases high number of product ions that in some cases are characteristic for certain structures of the steroid backbone. More specifically, preliminary results have shown major differences in fragmentation pattern for 17α/17β-isomers of the sulfate conjugates, but limited differentiation for 17α/17β-isomers of glucuronide conjugates and for 3α/3β- and 5α/5β-stereoisomers of both sulfate and glucuronide conjugates. Further to the suggestion of the current work, application on mesterolone administration studies confirmed—according to the World Anti-Doping Agency (WADA) TD2015IDCR—the presence of seven intact phase II metabolites, one glucuronide and six sulfates with use of LC–ESI–MS/(MS).  相似文献   
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Impact factor bias and proposed adjustments for its determination   总被引:3,自引:0,他引:3  
BACKGROUND: The impact factor (IF), a qualitative parameter used to evaluate scientific journals, has several flaws. The aim of the study was to evaluate two of its important constraints, journal self-citation and scientific field, and to investigate the potential for improvement. METHODS: We studied the five or six highest impact journals from each of seven medical fields: anesthesiology, dermatology, genetics and heredity, immunology, general and internal medicine, ophthalmology and surgery. To correct for journal self-citation, we divided the number of 1998 citations of papers published in 1996 and 1997, minus the self-citations, by the number of papers published in the same period. For inter-field normalization we divided the IF by the mean of the IFs of the upper quartile for the same category of medical field (IF/fcat). RESULTS: For the 36 journals, there was a negative correlation between IF and self-cited and self-citing rates (rs = -0.765, P < 0.001 and rs = -0.479, P < 0.003, respectively). Self-cited rate is the ratio of a journal's self-citations to the number of times it is cited by all journals including itself. Self-citing rate relates a journal's self-citations to the total references it makes. The IF/fcat for the 36 journals are positively correlated with their conventional IF (rs = 0.91, P < 0.001). CONCLUSION: Correcting the IF of the 36 journals for self-citation did not significantly change journal rankings. The adjusted IF/fcat to normalize for the scientific field was positively correlated with the conventional IF.  相似文献   
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Chromatin licensing and DNA replication factor 1 (CDT1), a protein of the pre-replicative complex, is essential for loading the minichromosome maintenance complex (MCM) helicases onto the origins of DNA replication. While several studies have shown that dysregulation of CDT1 expression causes re-replication and DNA damage in cell lines, and CDT1 is highly expressed in several human cancers, whether CDT1 deregulation is sufficient to enhance tumorigenesis in vivo is currently unclear. To delineate its role in vivo, we overexpressed Cdt1 in the mouse colon and induced carcinogenesis using azoxymethane/dextran sodium sulfate (AOM/DSS). Here, we show that mice overexpressing Cdt1 develop a significantly higher number of tumors with increased tumor size, and more severe dysplastic changes (high-grade dysplasia), compared with control mice under the same treatment. These tumors exhibited an increased growth rate, while cells overexpressing Cdt1 loaded greater amounts of Mcm2 onto chromatin, demonstrating origin overlicensing. Adenomas overexpressing Cdt1 showed activation of the DNA damage response (DDR), apoptosis, formation of micronuclei, and chromosome segregation errors, indicating that aberrant expression of Cdt1 results in increased genomic and chromosomal instability in vivo, favoring cancer development. In line with these results, high-level expression of CDT1 in human colorectal cancer tissue specimens and colorectal cancer cell lines correlated significantly with increased origin licensing, activation of the DDR, and microsatellite instability (MSI). © 2022 The Pathological Society of Great Britain and Ireland.  相似文献   
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Introduction The aim of our study was to evaluate the safety and efficacy of intra-arterial (IA) thrombolysis using recombinant tissue plasminogen activator (rt-PA) in patients with acute stroke due to occlusion in the anterior or posterior circulation. Methods We retrospectively analyzed the clinical and radiological data of 88 consecutive patients with acute ischemic stroke who underwent emergency cerebral angiography for the purpose of subsequent IA thrombolysis. The neurological deficit on admission and discharge was graded using the National Institutes of Health Stroke Scale (NIHSS) score. Baseline computer tomography (CT) scans were examined for any signs indicative of cerebral ischemia. The angiographic findings were classified according to the Thrombolysis in Myocardial Infarction (TIMI) score for myocardial infarction. Follow-up CT scans were examined for hemorrhagic complication. Results Of the 88 patients who underwent IA thrombolysis, 63 presented with complete or partial arterial occlusion in the suspected perfusion area. In these 63 patients, the median NIHSS score dropped from 15 points on admission to 10 points at discharge. The recanalization rate was 52.6% for partial and complete reperfusion. In-hospital mortality was 20.6% (9.1% for carotid, 44.4% for basilar territory occlusion). Intracerebral bleeding (ICB) occurred in 38.6% of the patients with occlusion in the anterior circulation, resulting in these patients presenting a worse clinical outcome than those without ICB. Only minor extracranial bleedings occurred in 20.6% of patients. Patients with ICB had a significantly higher frequency of ischemic signs on the baseline CT scan. Conclusion Occlusion of a cerebral artery is present in about 75% of the patients eligible for thrombolytic therapy. Intra-arterial thrombolysis using rt-PA in patients with acute ischemic stroke can achieve re-vascularization, although ICB remains the major risk factor affecting its efficacy.  相似文献   
68.
We investigated the effect of pressure application on the acupuncture point "extra 1" and on a control point on the bispectral index (BIS) values and on stress in 25 volunteers. In each volunteer, pressure was applied on the extra 1 point for 10 min and on a control point for 5 min on different days and in a randomized manner. The BIS value was recorded before applying pressure on the extra 1 point, during pressure application every 30 s for 10 min, and after pressure release. Regarding the control point, BIS values were recorded for 5 instead of 10 min during pressure application because acupressure on that point was associated with an unpleasant feeling. Each volunteer was asked to score stress before and after pressure application from 0 to 10. The BIS values were significantly reduced 2.5, 5, 7.5, and 10 min during pressure application on the extra 1 point (P < 0.001 for each comparison, respectively) and returned to the baseline values after pressure release. Pressure application on the control point decreased BIS values (P < 0.01 and P < 0.05 at 2.5 and 5 min, respectively). However, these values were maintained close to 90% and were significantly higher than those obtained during pressure on the extra 1 point (P < 0.001 and P < 0.001 for the 2.5- and 5-min comparisons). The verbal sedation score values obtained after pressure application on the extra 1 point were also lower when compared with the values obtained after pressure application on the control point (P < 0.001). IMPLICATIONS: This crossover study investigated the effect of pressure application on the acupuncture "extra 1" point in healthy volunteers. Acupressure applied for 10 min on the extra 1 point significantly reduced the BIS values and the verbal stress score when compared with acupressure applied on a control point.  相似文献   
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ABSTRACT

Children are engaging with technology to establish and maintain intimate relationships and explore their sexual identity. Sexting is one of the ways in which this exploration occurs, often on a consensual basis. In a first stage, this article reflects on the concepts of trust, control and privacy as prerequisites to engage in sexting. In a second stage, the authors explore the extent to which legislative instruments enable the legitimate exploration and expression of one’s sexual identity, and aim to minimise adverse consequences thereof. To that end, the fundamental right to privacy, data protection frameworks and criminal legislation on the non-consensual dissemination of sexual images were identified as potentially harnessing the concepts of trust, control and privacy. Questions were examined regarding the potential undermining thereof through the application of child sexual abuse material legislation to instances of (consensual) sexting between children.  相似文献   
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