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51.
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Common 82-nucleotide sequence unique to brain RNA.   总被引:25,自引:5,他引:25       下载免费PDF全文
Several randomly selected cDNA clones made from rat brain polyA+RNA have unusual properties. Although the cDNA inserts are 500-1,250 base pairs long, they hybridize to a 160-nucleotide RNA species that is present in brain but not in liver or kidney. Nucleotide sequence studies of two of the clones and hybridization studies show that a common 82-nucleotide sequence is responsible for the hybridization. The same sequence is located in the second intron of a rat growth hormone gene. These studies suggest that signals called "ID sequences" may be carried in the introns of genes and prescribe their tissue-specific expression.  相似文献   
53.

Objective

This was a systematic review and meta-analysis to compare outcomes between patients undergoing simultaneous or delayed hepatectomy for synchronous colorectal liver metastases.

Background

The optimal strategy for treating liver disease among patients with resectable synchronous colorectal liver metastases (CRLM) is unclear. Simultaneous resection of primary tumour and liver metastases may improve patient experience by reducing the number of interventions. However, there are concerns of increased morbidity compared to delayed resections.

Methods

A systematic literature search was performed using EMBASE, Medline, Cochrane library and Google scholar databases. Meta-analyses were performed using both random-effects and fixed-effect models. Publication and patient selection bias were assessed with funnel plots and sensitivity analysis.

Results

Thirty studies including 5300 patients were identified. There were no statistically significant differences in parameters relating to safety and efficacy between the simultaneous and delayed hepatectomy cohorts. Patients undergoing delayed surgery were more likely to have bilobar disease or undergo major hepatectomy. The average length of hospital stay was six days shorter with simultaneous approach [MD = ?6.27 (95% CI: ?8.20, ?4.34), p < 0.001]. Long term survival was similar for the two approaches [HR = 0.97 (95%CI: 0.88, 1.08), p = 0.601].

Conclusion

In selected patients, simultaneous resection of liver metastases with colorectal resection is associated with shorter hospital stay compared to delayed resections, without adversely affecting perioperative morbidity or long-term survival.  相似文献   
54.
The fine control of T‐cell differentiation and its impact on HIV disease states is poorly understood. In this study, we demonstrate that B‐lymphocyte‐induced maturation protein‐1 (Blimp‐1/Prdm1) is highly expressed in CD4+ T cells from chronically HIV‐infected (CHI) patients compared to cells from long‐term nonprogressors or healthy controls. Stimulation through the T‐cell receptor in the presence ofIL‐2 induces Blimp‐1 protein expression. We show here that Blimp‐1 levels are translationally regulated by microRNA‐9 (miR‐9). Overexpression of miR‐9 induces Blimp‐1 repression, restoring IL‐2 secretion in CD4+ T cells via reduction in the binding of Blimp‐1 to the il‐2 promoter. In CHI patients where IL‐2 expression is reduced and there is generalized T‐cell dysfunction, we show differential expression of both miR‐9 and Blimp‐1 in CD4+ cells compared with levels in long‐term nonprogressors. These data identify a novel miR‐9/Blimp‐1/IL‐2 axis that is dysregulated in progressive HIV infection.  相似文献   
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Objectives: Isolated intrahepatic recurrence is noted in up to 40% of patients following curative liver resection for colorectal liver metastases (CLM). The aims of this study were to analyse the outcomes of repeat hepatectomy for recurrent CLM and to identify factors predicting survival.Methods: Data for all liver resections for CLM carried out at one centre between 1998 and 2011 were analysed.Results: A total of 1027 liver resections were performed for CLM. Of these, 58 were repeat liver resections performed in 53 patients. Median time intervals were 10.5 months between the primary resection and first hepatectomy, and 15.4 months between the first and repeat hepatectomies. The median tumour size was 3.0 cm and the median number of tumours was one. Six patients had a positive margin (R1) resection following first hepatectomy. There were no perioperative deaths. Significant complications included transient liver dysfunction in one and bile leak in two patients. Rates of 1-, 3-and 5-year overall survival following repeat liver resection were 85%, 61% and 52%, respectively, at a median follow-up of 23 months. R1 resection at first hepatectomy (P = 0.002), a shorter time interval between the first and second hepatectomies (P = 0.02) and the presence of extrahepatic disease (P = 0.02) were associated with significantly worse overall survival.Conclusions: Repeat resection of CLM is safe and can achieve longterm survival in carefully selected patients. A preoperative knowledge of poor prognostic factors helps to facilitate better patient selection.  相似文献   
59.

Objectives

Total pancreatectomy (TP) is associated with significant morbidity and mortality. The severity of postoperative diabetes and existence of ‘brittle diabetes’ are unclear. This study sought to identify quality of life (QoL) and diabetes-specific outcomes after TP.

Methods

Patients who underwent TP were matched for age, sex and duration of diabetes with patients with type 1 diabetes. General QoL was assessed using the European Organization for Research and Treatment of Cancer (EORTC) core quality of life questionnaire QLQ-C30 and the PAN26 tool. Diabetes-specific outcomes were assessed using the Problem Areas in Diabetes (PAID) tool and an assessment of diabetes-specific complications and outcomes.

Results

A total of 123 patients underwent TP; 88 died (none of diabetic complications) and two were lost to follow-up. Of the remaining 33 patients, 28 returned questionnaires. Fourteen general and pancreas-specific QoL measurements were all significantly worse amongst the TP cohort (QLQ-C30 + PAN26). However, when diabetes-specific outcomes were compared using the PAID tool, only one of 20 was significantly worse. HbA1c values were comparable (P = 0.299), as were diabetes-related complications such as hypoglycaemic attacks and organ dysfunction.

Conclusions

Total pancreatectomy is associated with impaired QoL on general measures compared with that in type 1 diabetes patients. Importantly, however, there was almost no significant difference in diabetes-specific outcomes as assessed by a diabetes-specific questionnaire, or in diabetes control. This study does not support the existence of ‘brittle diabetes’ after TP.  相似文献   
60.

Background

Telehealth shows promise for supporting patients in managing their long-term health conditions, such as chronic obstructive pulmonary disease (COPD). However, it is currently unclear how patients, and particularly older people, may benefit from these technological interventions.

Aim

To explore patients’ expectations and experiences of using a mobile telehealth-based (mHealth) application and to determine how such a system may impact on their perceived wellbeing and ability to manage their COPD.

Design and setting

Embedded qualitative study using interviews with patients with COPD from various community NHS services: respiratory community nursing service, general practice, and pulmonary rehabilitation.

Method

An embedded qualitative study was conducted to which patients were recruited using purposive sampling to achieve maximum variation. Interviews were carried out prior to receiving the mHealth system and again after a 6-month period. Data were analysed using a grounded theory approach.

Results

The sample comprised 19 patients (aged 50–85 years) with varied levels of computer skills. Patients identified no difficulties in using the mHealth application. The main themes encapsulating patients’ experience of using the mHealth application related to an increased awareness of the variability of their symptoms (onset of exacerbation and recovery time) and reassurance through monitoring (continuity of care).

Conclusion

Patients were able to use the mHealth application, interpret clinical data, and use these within their self-management approach regardless of previous knowledge. Telehealth interventions can complement current clinical care pathways to support self-management behaviour.  相似文献   
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