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101.
We have encountered situations of patients with critical limb ischemia accompanied by pain at rest and necrosis, who hang their legs down from the bed during sleep. This lower limb position is known to be a natural position, which reduces pain in the lower extremity induced by ischemia. However, the effect of this position on blood flow of the lower extremity is poorly understood. We studied whether measurements of skin perfusion pressure (SPP) changes by leg position and the difference between healthy adults and patients with critical limb ischemia. The subjects of this study were 10 healthy adults and 11 patients with critical limb ischemia. Patients with critical limb ischemia, including both dorsum of foot and plantar of foot, having SPP of lower limbs of less than 40 mmHg (supine position) were the object of this study. SPP was measured on four positions (supine position, lower limbs elevation position, sitting position, and reclining bed elevation of 20° position). In sitting position, both the number of healthy adults and critical patients show significant increases in SPP compared with the other three positions. These results suggest that sitting position is effective to keep good blood stream of lower limbs not only in healthy adults but also in patients with critical limb ischemia. However, an appropriate leg position should not have lower limbs hang downwards for long periods time because edema is caused by the fall in venous return in lower limbs, and the wound healing is prolonged.Our clinical research could be more useful in the future, particularly in developing countries, for surgeons managing wounds in leg and foot and preserving ischemic limbs.KEY WORDS: Critical limb ischemia, peripheral arterial disease, position, skin perfusion pressure  相似文献   
102.
103.

Purpose

To explore the possibility of targeted biopsy (TBx) using transrectal ultrasound (US) with perflubutane microbubbles, we studied the findings of different cancerous tissue imaging modalities and evaluated needle biopsy in prostate cancer (PCa) using contrast-enhanced US (CEUS) in a multicenter clinical trial.

Methods

Seventy-one patients undergoing prostate biopsy received intravenous injection of perflubutane microbubbles (Sonazoid®). We evaluated and compared images obtained by CEUS. The safety observation period was 2 days after contrast administration.

Results

Among the 30 patients with cancer, one or more sites with findings suggestive of cancer in CEUS were detected in 23 patients (32.4%) by TBx. Although 22 patients had positive cores of cancer by systematic biopsy (SBx), 8 patients had positive cores of cancer in TBx alone (11.3%). There was a significant difference in cancer detection rate by TBx between two cohorts with PSA < 10 ng/mL (22.9%) and PSA ≥ 10 ng/mL (52.2%) (P < 0.02). Close observation of various CEUS findings with Sonazoid® enabled targeting of cancerous areas, and consequently, a significant difference (P < 0.05) in the detection rate of cancer was recognized in the transition zone (TZ): SBx; 21/120 (17.5%) and TBx; 17/55 (30.9%). The incidence of adverse events was 6.7% and that of adverse reactions was 4%.

Conclusions

CEUS with Sonazoid® improved the detection rate of PCa by visualizing cancerous lesions. More detailed examination of CEUS images provided efficient characterization especially in the TZ area. TBx according to this procedure is expected to enable a lower number of biopsies and more accurate diagnosis of PCa.  相似文献   
104.
105.
Renal cell carcinoma is the most common malignant tumor originating from the kidney. Compared with other solid tumors, it does not respond to traditional management modalities, such as chemotherapy and radiotherapy. However, it is well known that renal cell carcinoma represents one of the most immune‐responsive cancers and several immunotherapeutic strategies have been investigated in the management of renal cell carcinoma with variable degrees of success. The development of immunotherapy with α‐interferon or high‐dose interleukin‐2 is the best established treatment, and is associated with durable disease control. Although the lack of defined antigens in renal cell carcinoma has hindered more specific vaccine development, research regarding vaccination therapy has been of special interest for the treatment of renal cell carcinoma for more than 30 years. At present, there are three types of cell‐based vaccines in renal cell carcinoma treatment: autologous tumor‐cell vaccines, genetically modified tumor vaccines and dendritic cell‐based vaccines. A further type is peptide‐based vaccination with tumor‐associated antigens as possible targets, such as carbonic anhydrase IX, survivin and telomerase that are overexpressed in renal cell carcinoma. In the present article, we review data from completed clinical trials of vaccine therapy, and discuss future trials to assess the current knowledge and future role of vaccine therapy for renal cell carcinoma in the era of recently developed targeted therapy.  相似文献   
106.

Background

The recent development of open magnetic resonance imaging (MRI) has provided an opportunity for the next stage of image-guided surgical and interventional procedures. The purpose of this study was to evaluate the feasibility of laparoscopic surgery under the pneumoperitoneum with the system of an open MRI operating theater.

Methods

Five patients underwent laparoscopic surgery with a real-time augmented reality navigation system that we previously developed in a horizontal-type 0.4-T open MRI operating theater.

Results

All procedures were performed in an open MRI operating theater. During the operations, the laparoscopic monitor clearly showed the augmented reality models of the intraperitoneal structures, such as the common bile ducts and the urinary bladder, as well as the proper positions of the prosthesis. The navigation frame rate was 8 frames per min. The mean fiducial registration error was 6.88 ± 6.18 mm in navigated cases. We were able to use magnetic resonance–incompatible surgical instruments out of the 5-Gs restriction area, as well as conventional laparoscopic surgery, and we developed a real-time augmented reality navigation system using open MRI.

Conclusions

Laparoscopic surgery with our real-time augmented reality navigation system in the open MRI operating theater is a feasible option.  相似文献   
107.

Purpose

Nephron sparing surgery is an effective surgical option in patients with renal cell carcinoma. Laparoscopic partial nephrectomy involves clamping and unclamping techniques of the renal vasculature. This study compared the postoperative renal function of partial nephrectomy using an estimation of the glomerular filtration rate (eGFR) for a Japanese population in 3 procedures; open partial nephrectomy in cold ischemia (OPN), laparoscopic partial nephrectomy in warm ischemia (LPN), and microwave coagulation using laparoscopic partial nephrectomy without ischemia (MLPN).

Materials and Methods

A total of 57 patients underwent partial nephrectomy in Yokohama City University Hospital from July 2002 to July 2008. 18 of these patients underwent OPN, 17 patients received MLPN, and 22 patients had LPN. The renal function evaluation included eGFR, as recommended by The Japanese Society of Nephrology.

Results

There was no significant difference between the 3 groups in the reduction of eGFR. eGFR loss in the OPN group was significantly higher in patients that experienced over 20 minutes of ischemia time. eGFR loss in LPN group was significantly higher in patients that experienced over 30 minutes of ischemia time.

Conclusion

This study showed that all 3 procedures for small renal tumor resection were safe and effective for preserving postoperative renal function.Key Words: eGFR, Partial nephrectomy, Renal function, Laparoscopic partial nephrectomy  相似文献   
108.

Background

The significance of perineural invasion in extrahepatic cholangiocarcinoma has not been fully elucidated. This study aims to determine the prognostic impact of and optimal treatment strategy for perineural invasion in patients with extrahepatic cholangiocarcinoma.

Methods

Medical records of 133 patients with extrahepatic cholangiocarcinoma who underwent curative resection were reviewed retrospectively. Ninety-eight patients had perineural invasion and 35 patients did not. Univariate and multivariate survival analyses were performed to clarify the prognostic impact of and optimal treatment strategy for perineural invasion.

Results

Only tumor differentiation (P?=?0.024) was independently associated with perineural invasion in the multivariate logistic regression model. Multivariate survival analysis revealed that perineural invasion (P?=?0.002), resection margin status (P?=?0.016), and International Union Against Cancer (UICC) pT factor (P?=?0.015) were independent prognostic factors of overall survival. Overall 5-year survival rates for patients with and without perineural invasion were 28 and 74 %, respectively. Among 98 patients with perineural invasion, the use of adjuvant chemotherapy (P?=?0.003), lymph node status (P?=?0.015), resection margin status (P?=?0.008), and UICC pT factor (P?=?0.016) were independently associated with overall survival by multivariate analysis. Overall 5-year survival rates for patients with perineural invasion who did and did not receive adjuvant chemotherapy were 33 and 21 %, respectively (P?=?0.023).

Conclusions

Perineural invasion is a potent prognostic factor in extrahepatic cholangiocarcinoma. Adjuvant chemotherapy may improve the overall survival of patients with perineural invasion.  相似文献   
109.
This article presents a prototype of an intraoral device that facilitates preparation of parallel guide planes with accuracy and minimal occlusal divergence. The design of this device facilitates transfer of the desired path of insertion from the diagnostic cast to the mouth quickly and efficiently.  相似文献   
110.
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