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1.

Background  

For patients suffering of recurrent breast cancer within the irradiated breast, generally mastectomy is recommended. The normal tissue tolerance does not permit a second full-dose course of radiotherapy to the entire breast after a second breast-conserving surgery (BCS). A novel option is to treat these patients with partial breast irradiation (PBI). This approach is based on the hypothesis that re-irradiation of a limited volume will be effective and result in an acceptable frequency of side effects. The following report presents a single center experience with intraoperative radiotherapy (IORT) during excision of recurrent breast cancer in the previously irradiated breast.  相似文献   
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The mechanism by which S-adenosylmethionine (SAM) and adenosine (Ado) increase ATP levels in intact human erythrocytes in vitro has been compared. The use of erythrocytes from healthy controls and from subjects totally deficient in adenine phosphoribosyltransferase (APRT), plus inhibitors of adenosine kinase (AK) and adenosine deaminase (ADA) separately and together, has enabled us to demonstrate that this increment in ATP levels occurred via totally different metabolic routes. The results show that: (i) whilst the Ado-induced increment in ATP was AK dependent, that produced by SAM was independent of AK; and (ii) the SAM-induced increment in ATP was totally dependent on APRT and that some of the increment produced by Ado might also be APRT dependent. The above data are consistent with the metabolism of SAM to ATP by a route recently identified by us whereby ATP is formed from deoxyadenosine: namely binding to the enzyme S-adenosylhomocysteine hydrolase with subsequent release of adenine and further conversion to ATP via APRT.  相似文献   
3.
Explicit scoring criteria based on the Taylor-Osterrieth method were developed for the Rey-Osterrieth and Taylor Complex Figure Tests. Without such criteria, clinicians and researchers are left to develop their own idiographic scoring systems, leading to low interrater reliability, especially in the middle range of scores. Criteria were applied to the copy and 30-min recall protocols of 101 subjects infected with HIV. Results indicate that the criteria presented are reliable across a wide range of scores, making them useful for tracking subtle changes over time. Independent raters were within two points of each other on 90.1 % of the copy and 88.1% of recall scores, with a maximum disagreement of five points on two copy protocols. The Taylor figure was also found to be more easily remembered than the Rey-Osterrieth, calling into question their interchangeability. Explicit criteria are particularly useful in research settings. They ensure interrater reliability over time and across examiners in longitudinal studies, enhance the detection of subtle differences within the normal range, and allow comparison of results obtained by different investigators.  相似文献   
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The development of left ventricular cardiomyocyte hypertrophy in response to increased hemodynamic load and neurohormonal stress is initially a compensatory response. However, persistent stress eventually leads to dilated heart failure, which is a common cause of heart failure in human hypertensive and valvular heart disease. We have recently reported that Rho-associated coiled-coil containing protein kinase 1 (ROCK1) homozygous knockout mice exhibited reduced cardiac fibrosis and cardiomyocyte apoptosis, while displaying a preserved compensatory hypertrophic response to pressure overload. In this study, we have tested the effects of ROCK1 deficiency on cardiac hypertrophy, dilation, and dysfunction. We have shown that ROCK1 deletion attenuated left ventricular dilation and contractile dysfunction, but not hypertrophy, in a transgenic model of Gαq overexpression-induced hypertrophy which represents a well-characterized and highly relevant genetic mouse model of pathological hypertrophy. Although the development of cardiomyocyte hypertrophy was not affected, ROCK1 deletion in Gαq mice resulted in a concentric hypertrophic phenotype associated with reduced induction of hypertrophic markers indicating that ROCK1 deletion could favorably modify hypertrophy without inhibiting it. Furthermore, ROCK1 deletion also improved contractile response to β-adrenergic stimulation in Gαq transgenic mice. Consistent with this observation, ROCK1 deletion prevented down-regulation of type V/VI adenylyl cyclase expression, which is associated with the impaired β-adrenergic signaling in Gαq mice. The present study establishes for the first time a role for ROCK1 in cardiac dilation and contractile dysfunction.  相似文献   
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Background: Lesch–Nyhan disease (LND) is a rare X-linked recessive neurogenetic disorder caused by deficiency of the purine salvage enzyme hypoxanthine phosphoribosyltransferase (HPRT, EC 2.4.2.8) which is responsible for recycling purine bases into purine nucleotides. Affected individuals have hyperuricemia leading to gout and urolithiasis, accompanied by a characteristic severe neurobehavioural phenotype with compulsive self-mutilation, extrapyramidal motor disturbances and cognitive impairment. Aim: For its theoretical therapeutic potential to replenish the brain purine nucleotide pool, oral supplementation with S-adenosylmethionine (SAMe) was trialed in 5 Malaysian children with LND, comprising 4 related Malay children from 2 families, including an LND girl, and a Chinese Malaysian boy. Results: Dramatic reductions of self-injury and aggressive behaviour, as well as a milder reduction of dystonia, were observed in all 5 patients. Other LND neurological symptoms did not improve during SAMe therapy. Discussion: Molecular mechanisms proposed for LND neuropathology include GTP depletion in the brain leading to impaired dopamine synthesis, dysfunction of G-protein-mediated signal transduction, and defective developmental programming of dopamine neurons. The improvement of our LND patients on SAMe, particularly the hallmark self-injurious behaviour, echoed clinical progress reported with another purine nucleotide depletion disorder, Arts Syndrome, but contrasted lack of benefit with the purine disorder adenylosuccinate lyase deficiency. This first report of a trial of SAMe therapy in LND children showed remarkably encouraging results that warrant larger studies.  相似文献   
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BackgroundCongenital thrombophilia is a risk factor for venous thromboembolism (VTE). Whether it is associated with increased risk of arterial disease is today a matter of debate. We aimed to look for early signs of atherosclerotic alterations in carriers of inherited thrombophilic alterations (ITA).MethodsBetween January 2006 and September 2008 ultrasonography assessment of the carotid arteries with measurement of intima-media thickness (IMT), and determination of the ankle/brachial pressure index (ABI), was performed in: a) 161 carriers of ITA (deficiency of antithrombin, protein C or S, factor V Leiden or prothrombin G20210A mutations), 84 of whom with previous VTE, and b) 180 subjects without ITA, matched for age, sex and previous VTE. All subjects were < 66 year old.ResultsCarotid plaques were found in 8 subjects [3 (1.9%) with ITA]. Increased IMT values (> 1 mm) were detected in 6 subjects with and 1 without thrombophilia (p = 0.055). The prevalence of IMT values > 90th percentile was not different in subjects with/without thrombophilia (15.2% vs 11.6%, p = 0.416). At multivariate analysis only age was significantly associated with increased odds ratios for IMT values > 90th percentile. No subjects had abnormal (< 0.9) ABI values.ConclusionsThe present study, the first to investigate the presence of atherosclerotic markers in relatively young subjects with inherited thrombophilia, did not find a particular prevalence of signs of early atherosclerotic markers in these subjects.  相似文献   
10.
Background: The Magpie Trial compared magnesium sulfate with placebo for women with preeclampsia. The objective of this study was to explore women's views and experiences of participating in the Magpie Trial in the United Kingdom. Methods: Postal questionnaires were sent to 771 women participants in the Magpie Trial to assess long‐term health of UK women and children. The questionnaire included three questions exploring women's experience of participating in the trial: (a) If time suddenly went backward, and you had to do it all over again, would you agree to participate in the Magpie Trial? (b) Please tell us if there was anything about the Magpie Trial that you think could have been done better; and (c) Please tell us if there was anything about the Magpie Trial, or your experience of joining the trial, that you think was particularly good. Results: Overall, 619 of the 771 women who were sent questionnaires returned them. In response to the three questions: (a) 58 percent (356) of women responded “definitely yes,” 27 percent (169) “probably yes,” 4 percent (23) “probably no,” 5 percent (33) “definitely no,” and 5 percent (34) “not sure.” No clear evidence was shown of a relationship with allocated treatment, although women who responded “probably or definitely no” were more likely to have had side effects from trial treatment. (b) Although 44 percent of women stated that nothing could have been done better, free text suggestions related to content of recruitment information, and its timing, and wanting to know treatment allocation and trial results. c) Women were generally extremely positive about being followed up and receiving trial results. Conclusions: Women were largely positive about participation in the trial and its follow‐up, but still reported ways they believed the study could have been improved, such as more information, given earlier, which also has implications for clinical care.  相似文献   
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