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11.
Vitrification, an ultra-rapid cooling technique, offers a new perspective in attempts to develop an optimal cryopreservation procedure for human oocytes and embryos. To further evaluate this method for human oocytes, 796 mature oocytes (metaphase II) were collected from 120 volunteers. Since Italian legislation allows the fertilization of a maximum of only three oocytes per woman, there were 463 supernumerary oocytes; instead of being discarded, they were vitrified. When, in subsequent cycles, these oocytes were utilized, 328 out of 330 (99.4%) oocytes survived the warming procedure. The fertilization rate, pregnancy rate and implantation rate per embryo were 92.9, 32.5 and 13.2% respectively. Thus, as already reported in the literature, the vitrification procedure seems to be highly effective, safe (since healthy babies have been born) and easy to apply. In situations where embryo cryopreservation is not permitted (as in Italy), there is now good indication for routine application of the method, once further standardization is achieved.  相似文献   
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OBJECTIVE: We reviewed our experience in the surgical management of 80 patients with colorectal pulmonary metastases and investigated factors affecting survival. MATERIAL AND METHODS: From January 1980 to December 2000, 80 patients, 43 women and 37 men with median age 63 years (range 38-79 years) underwent 98 open surgical procedure (96 muscle-sparing thoracotomy, one clamshell and one median sternotomy) for pulmonary metastases from colorectal cancer (three pneumonectomy, 17 lobectomy, seven lobectomy plus wedge resection, six segmentectomy, three segmentectomy plus wedge resection and 62 wedge resection). Pulmonary metastases were identified at a median interval of 37.5 months (range 0-167) from primary colorectal resection. Second and third resections for recurrent metastases were done in seven and in four patients, respectively. RESULTS: Operative mortality rate was 2%. Overall, 5-year survival was 41.1%. Five-year survival was 43.6% for patients submitted to single metastasectomy and 34% for those submitted to multiple ones. Five-year survival was 55% for patients with disease-free interval (DFI) of 36 months or more, 38% for those with DFI of 0-11 months and 22.6% for those with DFI of 12-35 months (P=0.04). Five-year survival was 58.2% for patients with normal preoperative carcino-embryonic antigen (CEA) levels and 0% for those with pathologic ones (P=0.0001). Patients submitted to second-stage operation for recurrent local disease had 5-year survival rate of 50 vs. 41.1% of those submitted to single resection (P=0.326). CONCLUSIONS: Pulmonary resection for metastases from colorectal cancer may help survival in selected patients. Single metastasis, DFI>36 months, normal preoperative CEA levels are important prognostic factors. When feasible, re-operation is a safe procedure with satisfactory long-term results.  相似文献   
15.
The levels of the soluble (s) CD40:sCD40 ligand (L) dyad, which belongs to the tumor necrosis factor (TNF)-alpha:TNF-alpha-receptor superfamily, are significantly increased in the cerebrospinal fluid (CSF), but not the serum of cobalamin (Cbl)-deficient (Cbl-D) rats. They were normalized or significantly reduced after treatment with Cbl, transforming growth factor-beta1 or S-adenosyl-L-methionine, and the normal myelin ultrastructure of the spinal cord was concomitantly restored. The concomitance of the two beneficial effects of these treatments strongly suggests that the increases in CSF sCD40:sCD40L levels may participate in the pathogenesis of purely myelinolytic Cbl-D central neuropathy in the rat. In keeping with this, an anti-CD40 treatment prevented myelin lesions.  相似文献   
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Interstitial laser hyperthermia (ILH) is an in situ ablative technique used for the treatment of colorectal liver metastases. At present, few data exist concerning the optimum power settings required to maximize tissue necrosis.The aim of this study was to establish the dose-response relationship between the laser power setting and the extent of tissue necrosis produced in liver and tumor tissue, as well as the pattern of necrosis in a murine model of liver metastases. An intrasplenic induction model of liver metastases in 4- to 6-week-old male inbred CBA mice was used. Laser hyperthermia was applied to liver and tumor tissue using a bare optical quartz fiber from a Laserex SLY500 Nd:YAG surgical laser generator. Two-watt and 5-watt power settings were used at specific time intervals. The livers were then excised, fixed in formalin, and the extent and degree of necrosis were measured. Results were expressed as mean ? standard deviation and were normally distributed. Analysis of variance was performed, and the least significant difference was used for post hoc tests. A P value of less than 0.05 was considered significant. Interstitial laser hyperthermia at 5 watts of power produced larger diameters of necrosis than did 2 watts for specific exposure times in normal liver tissue. However, when the total energy applied was compared, there was no significant difference in the diameters of tissue necrosis produced by the two power settings. The diameter of tissue necrosis in the normal liver increased from 2 mm at 10 joules to 8 mm at 600 joules of energy. Within tumor tissue, ILH at 2 and 5 watts produced similar diameters of necrosis for specific exposure times. When amounts of total energy applied were compared, ILH at the lower power setting (2 watts) produced a significantly larger diameter of necrosis than the higher power setting (5 watts). The diameter of necrosis achieved in tumor tissue was significantly larger than that in normal liver tissue at both power settings, for an equivalent amount of applied energy. The difference was more pronounced when ILH was performed at the lower power setting. The maximum diameter of necrosis achieved was 6.8 ± 0.7 mm in normal liver tissue and 7.7 ± 0.8 mm in tumor tissue. Charring of the fiber tip was delayed when the lower power setting was used, occurring after 20 seconds of exposure, compared to 5 seconds at the higher power setting. Similarly, cavitation occurred initially at 50 seconds at 5 watts of power and was delayed until 90 seconds of exposure at 2 watts of power. Histopathologic findings revealed an elliptical area of homogeneous necrosis, with a central acellular coagulum surrounded by intact but nonviable tissue. ILH is capable of producing highly reproducible, uniform, and complete tissue necrosis. The diameter of necrosis is related to the total energy applied. At low-power settings at any given amount of applied energy, a significantly larger diameter of tissue necrosis was achieved in tumor tissue compared to normal liver tissue.  相似文献   
17.
Axial‐flow left ventricular assist devices (LVADs) are increasingly used as destination therapy in end‐stage chronic heart failure (CHF), as they improve survival and quality of life. Their effect on exercise tolerance in the early phase after implantation is still unclear. The aim of this study was to evaluate the effect of LVADs on the exercise capacity of a group of CHF patients within 2 months after initiation of circulatory support. Cardiopulmonary exercise test data were collected for 26 consecutive LVAD‐implanted CHF patients within 2 months of initiation of assistance; the reference group consisted of 30 CHF patients not supported by LVAD who were evaluated after an episode of acute heart failure. Both LVAD and reference groups showed poor physical performance; LVAD patients achieved lower workload (LVAD: 36.3 ± 9.0 W, reference: 56.6 ± 18.2 W, P < 0.001) but reached a similar peak oxygen uptake (peak VO2; LVAD: 12.5 ± 3.0 mL/kg/min, reference: 13.6 ± 2.9 mL/kg/min, P = ns) and similar percentages of predicted peak VO2 (LVAD: 48.8 ± 13.9%, reference: 54.2 ± 15.3%, P = ns). While the values of the O2 uptake efficiency slope were 12% poorer in LVAD patients than in reference patients (1124.2 ± 226.3 vs. 1280.2 ± 391.1; P = ns), the kinetics of VO2 recovery after exercise were slightly better in LVAD patients (LVAD: 212.5 ± 62.5, reference: 261.1 ± 80.2 sec, P < 0.05). In the first 2 months after initiation of circulatory support, axial‐flow LVAD patients are able to sustain a low‐intensity workload; though some cardiopulmonary exercise test parameters suggest persistence of a marked physical deconditioning, their cardiorespiratory performance is similar to that of less compromised CHF patients, possibly due to positive hemodynamic effects beginning to be produced by the assist device.  相似文献   
18.

Background

Five percent of all patients with breast cancer have distant metastatic disease at initial presentation. Because metastatic breast cancer is considered to be an incurable disease, it is generally treated with a palliative intent. Recent non-randomized studies have demonstrated that (complete) resection of the primary tumor is associated with a significant improvement of the survival of patients with primary metastatic breast cancer. However, other studies have suggested that the claimed survival benefit by surgery may be caused by selection bias. Therefore, a randomized controlled trial will be performed to assess whether breast surgery in patients with primary distant metastatic breast cancer will improve the prognosis.

Design

Randomization will take place after the diagnosis of primary distant metastatic breast cancer. Patients will either be randomized to up front surgery of the breast tumor followed by systemic therapy or to systemic therapy, followed by delayed local treatment of the breast tumor if clinically indicated. Patients with primary distant metastatic breast cancer, with no prior treatment of the breast cancer, who are 18 years or older and fit enough to undergo surgery and systemic therapy are eligible. Important exclusion criteria are: prior invasive breast cancer, surgical treatment or radiotherapy of this breast tumor before randomization, irresectable T4 tumor and synchronous bilateral breast cancer. The primary endpoint is 2-year survival. Quality of life and local tumor control are among the secondary endpoints. Based on the results of prior research it was calculated that 258 patients are needed in each treatment arm, assuming a power of 80%. Total accrual time is expected to take 60 months. An interim analysis will be performed to assess any clinically significant safety concerns and to determine whether there is evidence that up front surgery is clinically or statistically inferior to systemic therapy with respect to the primary endpoint.

Discussion

The SUBMIT study is a randomized controlled trial that will provide evidence on whether or not surgery of the primary tumor in breast cancer patients with metastatic disease at initial presentation results in an improved survival.

Trial registration

NCT01392586.  相似文献   
19.
OBJECTIVE: Bronchioloalveolar carcinoma (BAC) is considered a subtype of adenocarcinoma of the lung, without pleural, stromal or vascular invasion (World Health Organization (WHO) classification). Previous reports had demonstrated a better prognosis following surgery for patients affected by early stage BAC than those affected by other type of non-small cell lung cancer (NSCLC). We aim to analyse differences between stage I peripheral nodular BAC and stage I peripheral adenocarcinoma of the lung, METHODS: From January 1, 1993 to December 31, 1999, 1158 patients were submitted to surgical resection for NSCLC. Out of them, 28 patients (2.4%) resulted affected by stage I peripheral pure BAC and 80 (6.9%) by stage I peripheral adenocarcinoma. We made a comparison between these two groups. RESULTS: The percentage of females in BAC patients was similar to that registered in adenocarcinoma patients (21.4 vs. 17.5%). No differences were detected between smokers in BAC and adenocarcinoma patients (P=0.331). The upper lobes were the most common sites of the primary tumour in both tumour subtypes (71.4 vs. 67.5%). Relapse of disease was less frequent in BAC than in adenocarcinoma patients (14.2 vs. 33.7%); recurrent disease developed intrathoracic with higher frequency in BAC patients (75 vs. 33.3%). Both 5-year disease-free and long-term survival were significantly higher in patients affected by BAC (81 vs. 51% and 86 vs. 71%, respectively) (P<0.05); when analysis is performed by dividing stage IA from IB tumours, BAC patients resulted to have higher DFS (stage IA, 93 vs. 58% - P=0.044; stage IB, 61 vs. 32.5%) and higher long-term survival (stage IA, 92 vs. 79%; stage IB, 75 vs. 56%). CONCLUSION: Patients with stage I pure BAC have significantly longer disease-free and overall survival than those with similar stage adenocarcinoma. Even if classified as subtype of adenocarcinoma, BAC is characterised by clinical behaviour less aggressive than similar stage adenocarcinoma.  相似文献   
20.
BACKGROUND: The primary purpose was to assess if VAS or Likert was relatively more suitable when assessing self-ratings of voice and speech in patients treated for laryngeal cancer. An additional purpose was to investigate whether the scales differed in measuring change after treatment. MATERIAL/METHODS: Using both VAS and Likert, 71 patients answered three questions at baseline and 12 months after treatment began. For test-retest analyses, additional data were used from 21 subjects. Non-parametric statistical methods suitable for comparing scales with different numbers of response alternatives were applied. RESULTS: Test-retest reliability was strongest for the Likert scale. From baseline to follow-up, both scales detected significant improvements. However, for some Likert scores the associated VAS values varied across a wide range, and this was true for assessments at baseline, at follow-up, and for score changes. At baseline the inter-scale concordance showed a greater number of disordered pairs than at follow-up and on both occasions the older group produced a greater number of disordered pairs. CONCLUSIONS: No support for the superiority of VAS over Likert was found. However, VAS may produce instability in response patterns. When using self-ratings of voice and speech to identify a need of further rehabilitation, Likert scales seem better suited.  相似文献   
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