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121.
Pulmonary sequestration is a congenital malformation characterised by cystic, non-functioning embryonic lung tissue with vascularisation of an abnormal systemic artery. They are classified as intralobar (75%) and extralobar (25%) and are more common in the left lung and lower lobes (60-90%). We report two cases of intralobar pulmonary sequestration located in the lower lobe of the left lung which were subjected to video-assisted thoracoscopic surgery (VATS). Both patients had recurrent infections for which, after performing imaging tests, they were diagnosed with intralobar pulmonary sequestration in the left lower lobe, with an afferent arterial branch to the malformation from the aorta. A lower lobectomy was performed by video-assisted surgery, dividing the aberrant aortic artery with an endostapler. A single thoracic chest tube was placed and removed on postoperative day 2 and the patients were discharged on the same day. In both cases, the pathology examination revealed intralobar pulmonary sequestration. Pulmonary sequestrations are uncommon malformations that can be operated on using minimally invasive techniques, thereby permitting early discharge and a low rate of complications.  相似文献   
122.
123.
The presence of mucin pools lacking neoplastic epithelium ("acellular" mucin) in resection specimens of rectal carcinoma after neoadjuvant chemoradiotherapy (CRT) is a well-recognized phenomenon. The current recommendation by the College of American Pathologists is to regard acellular mucin as a type of treatment response and not as residual tumor. However, data-based evidence for or against such an approach is incomplete. In this study, we systematically analyzed the pattern and significance of mucin pools in 108 consecutive, prospectively collected resection specimens from patients who had uT3-4 and/or uN1 rectal cancer and were treated with preoperative long-course CRT. The 108 patients, 39 female and 69 male, had a median age of 58.5 years. With every tumor entirely examined in whole-mount sections, mucin pools were identified in 33 cases (33 of 108, 31%); in 16 (15%) they were all acellular. The mucin pools were focal (10% to 50% of the entire lesion) in 25 cases and extensive (>50%) in 8 cases. Mucin pools were also noted in the lymph nodes in 6 cases (6%); 3 of these were entirely acellular. Five cases had mucin pools in both the primary site and the lymph nodes. When acellular mucin was considered as "no residual tumor," the complete pathologic response rate for the entire cohort was 22% (24 of 108). The pathologic stage of the residual tumor (ypT) was 0 or 1 for 27 cases (25%) and 2 to 4 for 81 cases. The pathologic stage of nodal disease (ypN) was 0 for 83 (77%) and 1 or 2 for 25 cases. When acellular mucin was considered as "residual tumor," the complete pathologic response rate dropped to 17%; ypT was upstaged in 10 tumors and ypN was upstaged in 2 tumors. With a median follow-up of 31 months, the 3-year recurrence-free survival (RFS) was 73% for the entire group. Advanced pathologic response and low pathologic stage of the residual tumor (determined based on the depth of only viable tumor cells) correlated significantly with better RFS. However, the correlation between pathologic response and RFS became insignificant when acellular mucin pools were considered as residual tumor. Neither the presence of mucin pools nor their extent or cellularity had an impact on RFS. Furthermore, none of the 12 patients whose ypT or ypN was upstaged by acellular mucin had recurrent disease (3-y RFS of 100%). Thus, our results suggest that mucin pools in rectal carcinoma after neoadjuvant CRT do not have a significant impact on patient outcome, supporting the College of American Pathologists recommendation that only viable tumor cells, not acellular mucin, are to be interpreted as residual disease in the tumor pathologic staging.  相似文献   
124.

Background

Resection of intact primary tumor is controversial in metastatic breast cancer patients. The aim of this study is to review the impact of surgical resection of primary tumor on overall survival and to assess the role of timing of surgery on survival rates.

Methods

208 patients with metastatic breast cancer diagnosed between 1982 and 2005 in the Hospital Clinico of Valencia (Spain) were analysed. Exclusion criteria were age >80, PS 3–4, Charlson score 3 or follow-up < 90 days. 123 of these underwent surgery and 85 did not. In order to assess the role of timing, the "surgery" cohort was divided into two sub-groups: "before" (n = 78) or "after" (n = 45) diagnosis of disseminated disease.

Results

In the surgery group, patients underwent mastectomy with axillary dissection (82.9%), without axillary dissection (8.9%) and conservative surgery (8.1%). After a median follow-up of 29.68 months, median OS in the "surgery" and the "non-surgery" groups were, 40.4 and 24.3 months. Removal of the primary tumor therefore had a significant positive impact on survival rates (p < 0.001). Benefits of surgery were observed mainly in patients with visceral disease (p = 0.005); no statistical differences were found in those with bone disease (p = 0.79). Univariate analysis for overall survival (OS) identified surgery, performance status, clinical T stage, hormone receptors and number and type of metastases as variables that impacted on survival. In the multivariate test, only resection of primary tumor and estrogen receptors maintained statistical significance, surgery having a protective effect with an HR 0.52 (95% CI 0.35–0.77). No differences in survival were found between the two sub-groups according to the timing of surgery: "before" vs "after"(p = 0.996).

Conclusions

Resection of primary tumor should be considered not only as a palliative or preventive strategy but also as an approach that possibly contributes to the control of the disease in selected patients.  相似文献   
125.
Percutaneous endoscopic colostomy (PEC), using the classic pull-through technique in the ascending or the descending colon, has been proven useful to treat chronic intestinal pseudo-obstruction. We report the case of a high-surgical risk 70-year-old male with refractory chronic intestinal pseudo-obstruction, in whom the ascending colon could not be reached due to tortuous left dolichocolon. Endoscopic-assisted colopexy and push colostomy in the proximal transverse colon was decided accordingly. Colopexy was performed under direct endoscopic vision in the proximal transverse colon using 3 preloaded T-fasteners surrounding the intended stoma site. The stoma tract was created with an introducer needle, allowing the advance of the 24 Fr 4-sleeve dilator over a guidewire. Afterwards, the dilator was removed and the peel-away sheath was left in place. Over the guidewire, a 20-Fr gastrostomy tube was advanced into the colon lumen through the covering, which was finally removed. The patient recovered uneventfully, despite postprocedure pneumoperitoneum, which was related to the technique. He died a month later due to unrelated comorbidities, without further abdominal complaints after discharge. This is the first report of PEC both using a push technique, and the first report in a different location than the ascending or the descending colon. We believe this novel push technique may be feasible for PEC, avoiding the need of reinsertion in patients with difficult colonoscopy.  相似文献   
126.
The aim of the present study was to determine the effect of low-level laser therapy (LLLT) on the expression of TNF-α and TGF-β in the tibialis anterior muscle of rats following cryoinjury. Muscle regeneration involves cell proliferation, migration and differentiation and is regulated by growth factors and cytokines. A growing body of evidence suggests that LLLT promotes skeletal muscle regeneration by reducing the duration of acute inflammation and accelerating tissue repair. Adult male Wistar rats (n = 35) were randomly divided into three groups: control group (no lesion, untreated, n = 5), cryoinjury without LLLT group (n = 15), and cryoinjury with LLLT group (n = 15). The injured region was irradiated three times a week using an AlGaInP laser (660 nm; beam spot 0.04 cm2, output power 20 mW, power density 500 mW/cm2, energy density 5 J/cm2, exposure time 10 s). Muscle remodeling was evaluated at 1, 7 and 14 days (long-term) following injury. The muscles were removed and total RNA was isolated using TRIzol reagent and cDNA synthesis. Real-time polymerase chain reactions were performed using TNF-α and TGF-β primers; GAPDH was used to normalize the data. LLLT caused a decrease in TNF-α mRNA expression at 1 and 7 days following injury and in TGF-β mRNA expression at 7 days following cryoinjury in comparison to the control group. LLLT modulated cytokine expression during short-term muscle remodeling, inducing a decrease in TNF-α and TGF-β.  相似文献   
127.

Background  

An unbuffered postprandial proximal gastric acid pocket (PPGAP) has been noticed in normal individuals and patients with gastroesophageal reflux disease (GERD). The role of gastric anatomy in the physiology of the PPGAP remains unclear. It is also unclear whether change in the PPGAP may contribute to GERD control. This study aims to analyze the presence of PPGAP in patients submitted to Nissen fundoplication.  相似文献   
128.

Background  

Recent data indicate that enhanced wear resistance can be obtained with new cross-linked ultra-high-molecular weight polyethylene (CL-UHMWPE) liners, in comparison with previous-generation liners. The current prospective, cohort study was undertaken to analyse whether the use of a new CL-UHMWPE (Rexpol) results in a lower wear rate than ultra-high-molecular weight polyethylene (UHMWPE) in a group of similar patients undergoing total hip arthroplasty (THA). This study provides the first clinical data with this particular CL-UHMWPE.  相似文献   
129.

Background and objectives

Blood pressure monitoring offers a limited understanding of the hemodynamic consequences of spinal anesthesia for cesarean delivery. The purpose of this study was to assess, with the aid of a non-invasive cardiac output monitor based on bioreactance, the hemodynamic changes during elective cesarean delivery under spinal anesthesia in which intermittent boluses of phenylephrine were used to prevent and treat hypotension.

Methods

This observational study was conducted with the Research Ethics Board approval, and all participants provided written informed consent. Healthy patients undergoing elective cesarean delivery under spinal anesthesia were enrolled. Intermittent boluses of phenylephrine were administered in an attempt to maintain systolic blood pressure at baseline levels, and patients were assessed with a non-invasive cardiac output monitor based on bioreactance. Hemodynamic data was collected continuously at baseline, and during the postspinal and postdelivery periods. Data was analyzed using a mixed model ANOVA, and a p < 0.05 was considered significant.

Results

Systolic blood pressure was maintained within 79.2 ± 14.2 and 105.8 ± 10.0 percent of baseline during the postspinal period, and 78.4 ± 11.3 and 100.9 ± 10.7 percent of baseline in the postdelivery period (mean ± SD) There were significant fluctuations in systolic blood pressure, heart rate, and cardiac output during the postspinal period, and significant fluctuations in systolic blood pressure and cardiac output in the postdelivery period.

Conclusions

A new non-invasive monitor based on bioreactance reveals significant hemodynamic fluctuations during cesarean delivery under spinal anesthesia, despite attempts to maintain blood pressure at baseline levels with intermittent boluses of phenylephrine.  相似文献   
130.
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