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21.
Mutations in the CLCN1 gene, encoding a muscle-specific chloride channel, can cause either recessive or dominant myotonia congenita (MC). The recessive form, Becker's myotonia, is believed to be caused by two loss-of-function mutations, whereas the dominant form, Thomsen's myotonia, is assumed to be a consequence of a dominant-negative effect. However, a subset of CLCN1 mutations can cause both recessive and dominant MC. We have identified two recessive and two dominant MC families segregating the common R894X mutation. Real-time quantitative RT-PCR did not reveal any obvious association between the total CLCN1 mRNA level in muscle and the mode of inheritance, but the dominant family with the most severe phenotype expressed twice the expected amount of the R894X mRNA allele. Variation in allelic expression has not previously been described for CLCN1, and our finding suggests that allelic variation may be an important modifier of disease progression in myotonia congenita.  相似文献   
22.
Liver transplantation (LT) for colorectal liver metastasis (CRLM) may provide excellent survival rates in patients with unresectable disease. High tumor load is a risk factor for recurrence and low overall survival (OS) after liver resection (LR). We tested the hypothesis that LT could offer better survival than LR in patients with high tumor load. LR performed at Padua University Hospital for CRLM was compared with LT for unresectable CRLM performed both at Oslo and Padua. High tumor load was defined as tumor burden score (TBS) ≥ 9, and inclusion criteria were as in the SECA-I transplant study. 184 patients were eligible: 128 LRs and 56 LTs. 5-year OS after LR and LT was 40.5% and 54.7% (= 0.102). In the high TBS cohort, 5-year OS after LR and LT was 22.7% and 52.2% (P = 0.055). In patients with Oslo score ≤ 2 and TBS ≥ 9 (13 LR; 24 LT) the 5-year OS after LR and LT was 14.6% and 69.1% (P = 0.002). The corresponding disease-free survival (DFS) was 0% and 22.9% (P = 0.005). Selected CRLM patients with low Oslo score and high TBS could benefit from LT with survival outcomes that are far better than what is achieved by LR.  相似文献   
23.
Because both Rhodamine 123 (R123) and hyperthermia have been shown to be cytotoxic, we examined their effect, independently and in combination, on five different human malignant cell lines in vitro and on cultured melanoma cells grown intradermally in nude mice. The cell lines examined include two human melanomas, UCLA-SO-M14 and UCLA-SO-M21, the colon cancer cell line HT29, the human lung cancer cell line P3, and the human breast cancer cell line B231. R123 and hyperthermia, when used in combination, were found to be cytotoxic for these five different human malignant cell lines in vitro. The two agents together appear to enhance the cytotoxic effect of each alone, as documented by synergistic ratios ranging from 2.31 to 45 for the different cell lines. In the "nude" mouse model, animals were treated with a combination of R123 and hyperthermia (43 degrees C for 90 min). A statistically significant (P = 0.04) decrease in tumor growth rate was observed when compared with the rate of tumor growth in untreated animals. The results suggest a potential role for R123 in combination with hyperthermia in the treatment of malignant cells.  相似文献   
24.
The end-to-end anastomotic technique and the telescoped anastomotic technique were compared in a paired experimental study of 200 primarily patent anastomoses in the femoral arteries and veins of rats. It was found that the arterial telescoped anastomosis was faster and simpler to perform and had a significantly lower frequency of late thrombotic deposition (13%) than the arterial end-to-end anastomosis (41%), although the patency rates at 1 week were equal (88%). Aneurysms at the site of the anastomosis were not observed in the arterial telescoped anastomoses, while initial stages of probable aneurysms were observed in 24% of the arterial end-to-end anastomoses. The venous telescoped anastomoses were also less time-consuming and simpler to construct. Although equal patency rates at 1 week were obtained (84%-88%), the venous telescoped anastomoses displayed a significantly more pronounced incidence of thrombotic deposition at the site of the anastomosis.  相似文献   
25.
PURPOSE: This Nordic multicenter phase II study evaluated the efficacy and safety of oxaliplatin combined with the Nordic bolus schedule of fluorouracil (FU) and folinic acid (FA) as first-line treatment in metastatic colorectal cancer. PATIENTS AND METHODS: Eighty-five patients were treated with oxaliplatin 85 mg/m(2) as a 2-hour infusion on day 1, followed by a 3-minute bolus injection with FU 500 mg/m(2) and, 30 minutes later, by a bolus injection with FA 60 mg/m(2) every second week. The same doses of FU and FA were also given on day 2. RESULTS: Fifty-one of 82 assessable patients achieved a complete (n = 4) or partial (n = 47) response, leading to a response rate of 62% (95% CI, 52% to 72%). Nineteen patients showed stable disease, and 12 patients had progressive disease. Thirty-eight of the 51 responses were radiologically confirmed 8 weeks later (confirmed response rate, 46%; 95% CI, 36% to 58%). The estimated median time to progression was 7.0 months (95% CI, 6.3 to 7.7 months), and the median overall survival was 16.1 months (95% CI, 12.7 to 19.6 months) in the intent-to-treat population. Neutropenia was the main adverse event, with grade 3 to 4 toxicity in 58% of patients. Febrile neutropenia developed in seven patients. Nonhematologic toxicity consisted mainly of neuropathy (grade 3 in 11 patients and grade 2 in another 27 patients). CONCLUSION: Oxaliplatin combined with the bolus Nordic schedule of FU+FA (Nordic FLOX) is a well-tolerated, effective, and feasible bolus schedule as first-line treatment of metastatic colorectal cancer that yields comparable results compared with more complex schedules.  相似文献   
26.
Purpose: The aim of the study was to determine the type and magnitude of detectable changes in pig multifocal electroretinography (mfERG) induced by the vitreoretinal surgical procedures necessary to gain access to the subretinal space. Methods: Twenty pigs underwent posterior segment surgery. Six animals had a vitrectomy (V), six had in addition a retinal bleb detachment (V + B); five had in addition a retinal diathermia on the bleb (V + B + D) and three received a retinotomy in the diathermized retinal area (V + B + D + R). mfERG evaluation was performed at baseline and 1 and 6 weeks postoperatively. Selected eyes were enucleated for histological evaluation. Results: The retinal detachments blebs all reattached spontaneously. All four surgical sequences resulted in slight, non‐significant changes in the mfERG peaks. A trend towards an amplitude reduction of the mfERG peaks N1, P1 and N2 were observed within the first postoperative week. After 6 weeks, all amplitudes had normalized. Of the implicit times only that of peak N1 (after retinal diathermia) was prolonged significantly at 1 week (P = 0.037). However, it returned to the preoperative level after 6 weeks. Histologically, the retinal detachment bleb was characterized by transient double layering of the retinal pigment epithelium (RPE) and loss photoreceptor outer segments. Conclusion: Access to the subretinal space in pigs can be gained without permanent detectable changes in the mfERG. A short‐term retinal detachment was found to cause only reversible electrophysiological and histological changes in the outer retina, which suggests that this procedure is tolerated well in the porcine retina. The size of the known destructive lesion (retinotomy) was too small to be detected, given the spatial resolution of the mfERG method applied. In the future, the presented protocol can be used to assess the functional outcome of surgery and transplantation in the subretinal space in pigs.  相似文献   
27.
The purpose of the present study was to investigate pharmacokinetics of procaterol in asthmatics and non‐asthmatics after nebulized and oral administration in relation to doping. Ten asthmatic and ten non‐asthmatic subjects underwent two pharmacokinetic trials. At first trial, 4 µg procaterol was administered as nebulization. At second trial, 100 µg procaterol was administered orally. Serum and urine samples were collected before and after administration of procaterol. Samples were analyzed by liquid chromatography‐tandem mass spectrometry (LC‐MS/MS). Serum and urine concentrations of procaterol were markedly higher after oral administration compared to nebulized administration. After oral administration, serum procaterol concentration‐time area under the curve (AUC) was higher (P ≤ 0.05) for asthmatics than non‐asthmatics. Likewise, urine concentrations were higher (P ≤ 0.01) for asthmatics than non‐asthmatics 4 (47 ± 12 vs. 28 ± 9 ng/mL) and 8 h (39 ± 9 vs. 15 ± 5 ng/mL) after oral administration. Detection of serum procaterol was difficult after nebulized administration with 38 samples (27%) below limit of quantification (LOQ) and only trends were observed. No differences were observed between asthmatics and non‐asthmatics in the urine concentrations of procaterol after nebulized administration. In summary, our data showed that asthmatics had higher urine concentrations of procaterol than non‐asthmatics after oral administration of 100 µg, whereas no difference was observed between the groups after nebulized administration. For doping control purposes, our observations indicate that it is possible to differentiate therapeutic nebulized administration of procaterol from prohibited use of oral procaterol. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
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ObjectiveTo investigate the incidence of cardiac arrhythmias at six months following traumatic spinal cord injury (SCI) and to compare the prevalence of arrhythmias between participants with cervical and thoracic SCI.DesignA prospective observational study using continuous twenty-four-hour Holter monitoring.SettingInpatient rehabilitation unit of a university research hospital and patient home setting.ParticipantsFifty-five participants with acute traumatic SCI were prospectively included. For each participant, the SCI was characterized according to the International Standards for Neurological Classification of SCI by the neurological level and severity according to the American Spinal Injury Association Impairment Scale.Outcome measuresComparisons between demographic characteristics and arrhythmogenic occurrences as early as possible after SCI (4 ± 2 days) followed by 1, 2, 3, 4 weeks and 6 month time points of Holter monitoring.ResultsBradycardia (heart rate [HR] <50 bpm) was present in 29% and 33% of the participants with cervical (C1–C8) and thoracic (T1–T12) SCI six months after SCI, respectively. The differences in episodes of bradycardia between the two groups were not significant (P < 0.54). The mean maximum HR increased significantly from 4 weeks to 6 months post-SCI (P < 0.001), however mean minimum and maximum HR were not significantly different between the groups at the six-month time point. There were no differences in many arrhythmias between recording periods or between groups at six months.ConclusionsAt the six-month timepoint following traumatic SCI, there were no significant differences in occurrences of arrhythmias between participants with cervical and thoracic SCI compared to the findings observed in the first month following SCI.  相似文献   
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