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101.
CT Venography (CTV) performed at the time of CT pulmonary angiography (CTPA) images the central, pelvic, and extremity venous circulation with minimal additional time, radiation, and no added contrast. CTV has been added to CTPA routinely at our Level I trauma center since 2000, and we sought to determine if this addition had increased the diagnostic yield of CTPA in trauma patients. The attending radiologist's interpretation of all CTPA-CTV studies performed over a 5-year period ending in August 2006 were retrospectively reviewed. CTPAs and CTVs were categorized as "positive", "negative", or "indeterminate" for pulmonary embolus (PE) and deep venous thrombosis (DVT). During the study period, 3798 patients underwent both a CTPA and CTV; 309 (8%) of these were trauma patients. Forty-four (14%) had a PE diagnosed on CTPA. Seventeen (6%) had a DVT diagnosed on CTV. In eight (3%), the CTV added clinically relevant data, diagnosing a DVT in a patient without PE. As the consequences of a missed pelvic DVT are high and the added time burden, radiation, and contrast required for a CTV are low, further investigation into optimizing the sensitivity of CTV performed at the time of CTPA is warranted.  相似文献   
102.
After low anterior resection for rectal cancer, approximately 50% of patients experience defecatory malfunction such as multiple evacuations, urgency, and soiling. Since the neorectum is constructed with the remaining colonic segment, it can only substitute for the rectum to a limited extent. A straight anastomosis is most frequently used when the rectal remnant is sufficient, such as in high anterior resection. When the height of anastomosis is close to the anal sphincter, a J-pouch, a side-to-end, or a transverse coloplasty pouch are constructed to achieve better postoperative bowel function. The advantage of J-pouch reconstruction is not only the increased volume but also may be decreased motility when compared with straight reconstruction. In terms of postoperative function, the side-to-end and transverse coloplasty pouch have both been reported to exhibit similar functional results to J-pouch reconstruction. To obtain optimal functional results, pouch reconstruction should be considered, especially when the height of anastomosis is at the levator plane.  相似文献   
103.
BACKGROUND: Microwave coagulation therapy (MCT) has become a safe and effective modality with which to treat hepatic tumors; MCT can be applied percutaneously, laparoscopically, thoracoscopically, and during laparotomy. When combined with magnetic resonance (MR) imaging, MCT can be used to treat hepatic tumors located in the subdiaphragmatic area that are difficult to approach by ultrasound, because of the overlaying lower lung field. METHODS: To determine the usefulness of thoracoscopy-assisted interventional MR-MCT (T-IVMR-MCT, n = 73), we compared patients with hepatic tumors that were treated with percutaneous IVMR-MCT (P-IVMR-MCT, n = 69) and with T-IVMR-MCT. RESULTS: None of patient background, complication and recurrence rate, or length of hospital stay significantly differed between the 2 groups. CONCLUSIONS: IVMR-MCT is a useful modality for treating hepatic tumors. Especially when tumors are located at the hepatic dome, T-IVMR-MCT was minimally invasive, while it appears to improve targeting of peridiagmatic hepatic lesions and has a complication profile similar to P-IVMR-MCT.  相似文献   
104.
Cui W  Hosaka N  Miyake T  Wang X  Guo K  Cui Y  Li Q  Song C  Feng W  Li Q  Takaki T  Nishida T  Inaba M  Ikehara S 《Transplantation》2008,85(8):1151-1158
BACKGROUND: Although bone marrow transplantation (BMT) has become a valuable strategy for the treatment of various intractable diseases in recent years, success rates remain low in elderly patients because of low thymic function. We have previously shown that fetal thymus transplantation (TT) with BMT is effective for elderly recipients in mice. METHODS: We performed fully major histocompatibility complex (MHC)-mismatched fetal TT from B6 (H-2) mice plus allogeneic BMT from C3H/HeN (H-2) mice by intra-bone marrow-BMT (IBM-BMT) using congenitally athymic nude (nu/nu) BALB/c (H-2), or BALB/c adult-thymectomized recipients to obtain triple chimeras. We next carried out the IBM-BMT+TT using senescence-accelerated mouse P1 strain (SAMP1) to examine whether this method would be applicable to aging mice. RESULTS: Triple chimeric mice survived for a long period with sufficient T-cell functions comparable to the mice treated with BMT plus MHC-matched TT, whereas those without TT survived for a short period with insufficient T-cell reconstitution. Almost all the hematolymphoid cells were derived from donor bone marrow cells. Interestingly, they showed tolerance to all three types of MHC determinants with donor-derived thymic dendritic cells in TT. Triple chimeric SAMP1 also survived for long periods with T-cell functions restored in contrast to non-TT SAMP1 recipients. CONCLUSION: These findings suggest that third party combined TT with allogeneic IBM-BMT may be more advantageous for elderly recipients with low thymic function, than IBM-BMT alone (without TT).  相似文献   
105.
Bare stents are commonly used for the treatment of malignant vena cava stenoses. However, the therapeutic effect of treatment using bare stents for cases with intraluminal tumor invasion is not satisfactory. We report a case with severe obstruction of the superior vena cava caused by tumor invasion of mediastinal lymph node metastases from colon cancer, which was successfully treated by the recanalization of superior vena cava using a polytetrafluoroethylene-covered Z stent. The covered stent could not be fully expanded at first, and re-obstruction developed at the stented site due to thrombus formation soon after stenting. So, the additional balloon dilatation made the stent expend fully on another day of stenting. After the balloon dilatation blood flow improved immediately and the clinical symptoms associated with the superior vena cava obstruction resolved. Thereafter no symptomatic recurrence has been observed in 12 months of follow-up period.  相似文献   
106.
A Japanese girl aged 13 years with myeloperoxidase anti-neutrophil cytoplasmic antibodies(MPO-ANCA)-associated glomerulonephritis(GN) progressed to end-stage renal failure after 7 years' clinical observation. She had been suffering from recurrent disease flare associated with serum MPO-ANCA elevation(i.e. 153 EU/ml, 208 EU/ml and 358 EU/ml, maximum at each of the episodes, normal < 10 EU/ml). Each flare was treated successfully with prednisolone combined with cyclophosphamide and azathioprine. However, her renal function gradually deteriorated, and peritoneal dialysis(PD) was initiated 7 years after the onset of the disease. During the clinical course, no extrarenal manifestations were observed. Due to subsidence of the serum MPO-ANCA titer(10 EU/ml) after starting PD, prednisolone and azathioprine were tapered thereafter. Her daily urine volume was preserved at approximately 600 ml at that time. She suddenly developed fatigue with severe anemia, oliguria and hypertension 4 months after discontinuation of immunosuppressive therapy. The serum titer of MPO-ANCA increased to 100 EU/ml. These clinical observation suggests that disease flare may occur in selected patients with MPO-ANCA-associated GN, who develop end-stage renal failure requiring PD. Although recurrent flare associated with an increased serological activity in a proportion of patients with lupus nephritis who have received dialysis has been reported to date, to our knowledge, a similar clinical observation in the MPO-ANCA-associated GN has not been reported. Selected patients with the disease should be followed with close observation after undergoing dialysis.  相似文献   
107.
BACKGROUND: To assess tissue characterization of oral tongue cancer and prediction of subclinical cervical lymph node metastasis, we investigated whether intraoral ultrasonography could be used in conjunction with a computer-aided diagnosis (CAD) system. METHODS: The study population comprised 109 patients with presurgical, clinical T1N0 or T2N0 oral tongue squamous cell carcinoma who underwent partial glossectomy. All the patients were examined by preoperative intraoral and postoperative ex vivo ultrasonography. To evaluate the ultrasonic images quantitatively, ultrasonographic parameters from tumor contour features were computed by using the proposed CAD system. The imaging results were correlated with histopathologic findings. RESULTS: Oral tongue cancer was clearly identified in all patients by intraoral ultrasonography. Ultrasonic images of oral tongue cancer reflected the histopathologic structures. Subclinical cervical lymph node metastasis was predicted by intraoral ultrasonography. In a logistic regression analysis using the proposed CAD system, the diagnostic sensitivity, specificity, and accuracy for prediction of subclinical lymph node metastasis were 87.2%, 84.3%, and 85.3%, respectively. CONCLUSIONS: Intraoral ultrasonography in conjunction with the proposed CAD system allows tissue characterization and prediction of subclinical cervical lymph node metastasis.  相似文献   
108.
We have found that steroid bolus withdrawal prior to graft reperfusion increased the incidence of acute cellular rejection (ACR). This study aims to clarify how initial steroid bolus (ISB) injection at reperfusion influences the kinetics of CD8(+) alloreactive immune responses immediately after living donor liver transplantation (LDLT). A total of 49 hepatitis C virus (HCV)-infected recipients were classified into 3 groups according to hierarchical clustering by preoperative CD8(+)CD45 isoforms. The naive T cell proportion was considerably higher in Group I than in Groups II and III, whereas Group II recipients had the highest effector memory (EM) T cells and Group III the highest effector T cells. The frequency of ACR was significantly higher in recipients without ISB than in those with ISB. In particular, the ACR rates were the highest in Group II without ISB. Following ISB, the proportion of effector T cells was promptly upregulated within 6 hours after graft reperfusion, simultaneously with the upregulation of CD27(-)CD28(-) subsets, interferon-gamma (IFN-gamma), tumor necrosis factor-alpha and perforin expression, which significantly correlated with increasing interleukin (IL)-12 receptor beta 1 cells. These were then downregulated to below preoperative levels by tacrolimus (Tac) administered at 24 hours. These changes did not occur in the absence of ISB. In Group II without ISB, the downregulation of IL-12Rbeta1(+) cells was the greatest, consistent with the highest rates of ACR and mortality (60%). In conclusion, ISB must be done in place, especially in Group II with preexisting high EM T cells, to enable the development of early allograft acceptance.  相似文献   
109.
What's new in pancreatic cancer treatment?   总被引:2,自引:0,他引:2  
Pancreatic cancer represents a major challenge to oncologists because of its high chemoresistant nature and dismal outcomes. Conventional therapy for advanced disease relied for a long time on palliative 5-fluorouracil (5-FU)-based chemotherapy, but with unsatisfactory results. The introduction of the novel antimetabolite gemcitabine provides new optimism for patients with advanced pancreatic cancer, as multiple clinical trials have demonstrated the superiority of gemcitabine over 5-FU and other agents for these patients. The benefits of gemcitabine over conventional therapies include improved response rate and enhanced survival, as well as improvement in disease-related symptoms and quality of life in these patients. With these data, gemcitabine is widely accepted worldwide as the therapy of choice by many oncologists for advanced pancreatic cancer. The current review presents an overview of the clinical studies of gemcitabine over the past decade for the treatment of patients with advanced pancreatic cancer. Other investigational regimens or uses (e.g., fixed dose-rate infusion, intraarterial infusion, adjuvant use, chemo-radiation, etc) are also reviewed. Received: October 27, 2001 / Accepted: November 16, 2001  相似文献   
110.
Linezolid belongs to a new class of synthetic antimicrobial agent that is effective for a variety of methicillin-resistant Staphylococcus aureus (MRSA) infections including bone and joint MRSA infections, but the effectiveness of linezolid for the treatment of MRSA spine infection remains controversial. In this study, we investigated the diffusion of linezolid or vancomycin into normal rabbit spinal tissues to determine the adequacy of linezolid for the treatment of spinal infection. The penetration efficacy of linezolid into the annulus fibrosus, nucleus pulposus, and vertebral bone (10, 8, and 10%, respectively) was lower than that of vancomycin (27, 11, and 14%, respectively). The penetration efficacy of linezolid into the bone marrow and iliopsoas muscle (88 and 84%, respectively), however, was higher than that of vancomycin (67 and 9%, respectively). These results suggest that linezolid is inadequate for the treatment of spine infection limited to the intervertebral disc, but may be effective for the treatment of infection extending into the muscle and bone marrow, such as in vertebral osteomyelitis, iliopsoas abscess, and postsurgical infection.  相似文献   
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