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81.
Hirai M  Iwata H  Ishibashi H  Ota T  Nakamura H 《Vascular》2008,16(2):95-100
The importance of measuring interface pressure and stiffness to characterize the elastic properties of materials has been stressed with regard to elastic stockings and elastic bandages. The objective of this study was to compare the pressure profiles of nine different elastic stockings and to quantify the effects of posture changes and exercise on compression. Using a pressure transducer (Air Pack Type Analyzer), the interface pressure associated with nine different elastic stockings was measured at level B1 during supine resting, standing, and exercise. The elastic stockings examined could be divided into two categories according to extensibility: short stretch (< 105% extensibility) and long stretch (> 105% extensibility). Short-stretch stockings include thick round-knitted stockings, firm round-knitted stockings, and flat-knitted stockings. Short-stretch stockings showed a higher peak working pressure and a larger pressure amplitude during exercise than long-stretch stockings. Short-stretch stockings can be expected to have more pronounced benefits for augmenting muscle pumping in the same way as short-stretch bandages. In selecting suitable elastic stockings for patients, the stiffness should be taken into account in addition to interface pressure.  相似文献   
82.
OBJECTIVE: To assess the feasibility and safety of radiofrequency ablation (RFA) with hand-assisted laparoscopic surgery (HALS) for hepatocellular carcinoma (HCC) in the caudate lobe with severe liver dysfunction. SUMMARY BACKGROUND DATA: HCC in the caudate lobe remains one of the most difficult locations where various treatments tend to pose problems regarding the optimal surgical approach. The technique of HALS has thus been proposed as a useful method for performing a safe RFA therapy. For this study, we assessed the feasibility and safety of RFA with HALS for the treatment of HCC in the caudate lobe with liver dysfunction. PATIENTS AND METHODS: Between July 1999 and February 2005, 5 patients who suffered from HCC in the caudate lobe were indicated for RFA. The percutaneous puncture was difficult and all patients have severe liver dysfunction with viral chronic hepatitis. Therefore, RFA was assisted by an inserted hand through a minimal skin incision under laparoscopic inspection. An intraoperative endoscopic ultrasound examination was performed before RFA to determine the tumor region. The hand-assisted minimal dissection around the caudate lobe was required to detect tumor and avoid injuries of other tissues. RFA for HCC was performed using a cooled-tip (Radionics Inc, Burligton, MA) connected to a RF generator under the programmed cyclic impedance. RESULTS: The surgical procedures consisted of 5 RFA to tumors in the caudate lobe with HALS, which was performed safely, and a postoperative computed tomography scan revealed a sufficient ablation in all patients. There was no operative mortality but 1 patient had minor bile leakage, which was treated conservatively, and all patients recovered and thus were eventually discharged. One patient had local recurrence after 3 months, 3 patients had tumor recurrences in another segment after 6 months. At a mean follow-up 32.2 months, all patients were still alive. CONCLUSIONS: RFA with HALS is considered to be a safe and feasible technique for HCC in the caudate lobe with liver dysfunction.  相似文献   
83.
An epidermoid cyst is a common occurrence in the skin. Such a cyst occurring in the retrorectal space, however, is extremely rare. We herein present a case of retrorectal epidermal cyst in a 67-year-old Japanese woman. She reported no symptoms and a perirectal mass behind the lower rectum was accidentally detected by computed tomography (CT). Contrast CT and magnetic resonance imaging revealed a cystic mass (76 x 70 x 63 mm) with a slightly enhanced thin wall which was attached to the lower rectum. The patient underwent surgery via a posterior approach. The mass was exposed after an excision of subcutaneous fat and was firmly adhered to the anal sphincter muscle. The cystic mass was completely removed without a proctectomy. Histologically, the cyst was diagnosed to be an epidermoid cyst. The postoperative course was uneventful, and the patient was discharged on postoperative day 9. A diagnosis of retrorectal cystic tumor is difficult, and a complete resection is necessary for the treatment of such tumors.  相似文献   
84.
This study investigated the mechanism of direct and indirect actions of fibroblast growth factor 2 (FGF-2) on osteoclast differentiation using two mouse cell culture systems. In the coculture system of osteoblasts and bone marrow cells, FGF-2 stimulated osteoclast formation. This effect was decreased markedly by osteoprotegerin (OPG) or NS-398, a selective cyclo-oxygenase 2 (COX-2) inhibitor. FGF-2 (> or = 10(-9) M) stimulated receptor activator of nuclear factor kappaB ligand/osteoclast differentiation factor (RANKL/ODF) messenger RNA (mRNA) expression from 2 h to 7 days in cultured osteoblasts. NS-398 did not affect the early induction but decreased the later one, indicating that the later effect is mediated by COX-2 induction in osteoblasts. To study the direct action of FGF-2 on osteoclast precursors, we used mouse macrophage-like cell line C7 cells that can differentiate into osteoclasts in the presence of soluble RANKL/ODF (sRANKL/ODF) and macrophage colony-stimulating factor (M-CSF). Although osteoblasts expressed all FGF receptors (FGFR-1 to -4), only FGFR-1 was detected in C7 cells at various differentiation stages. FGF-2 alone or in combination with sRANKL/ODF did not induce osteoclastogenesis from C7 cells; however, FGF-2 from lower concentrations (> or = 10(-11) M) significantly decreased osteoclast formation induced by M-CSF in the presence of sRANKL/ODF. FGF-2 did not alter mRNA levels of M-CSF receptor (Fms) or RANK in C7 cells. Immunoprecipitation/ immunoblotting analyses revealed that tyrosine phosphorylation of several cellular proteins including Fms in C7 cells induced by M-CSF was inhibited by FGF-2 in the presence of sRANKL/ODF. We conclude that FGF-2 regulates osteoclast differentiation through two different mechanisms: (1) an indirect stimulatory action via osteoblasts to induce RANKL/ODF partly through COX-2 induction and prostaglandin production and (2) a direct inhibitory action on osteoclast precursors by counteracting M-CSF signaling.  相似文献   
85.
STUDY OBJECTIVE: To evaluate the safety and efficacy of small-bore, silastic drains for patients undergoing general thoracic surgery. PATIENTS AND METHODS: Twenty-five patients who received soft, small-bore, silastic drains were compared with 17 patients who received semi-rigid double lumen (DL) tubes retrospectively. RESULTS: The pain score was significantly lower in patients who received the silastic tubes in video-assisted thoracoscopic surgery (VATS) cases on postoperative days 5 and 6 , after continuous epidural analgesia had finished (P=0.018). No specific morbidity was seen in the patients who received silastic tubes. CONCLUSION: We considered that soft, small-bore silastic drains were just as effective as traditional DL tubes, but caused less pain especially in VATS cases.  相似文献   
86.
To identify mitochondrial haplogroups that confer resistance against or susceptibility to metabolic syndrome, we performed a large-scale association study on 1,337 unrelated Japanese individuals, including 871 subjects with metabolic syndrome and 466 control subjects. Metabolic syndrome was diagnosed according to modified National Cholesterol Education Program Adult Treatment Panel III guidelines, using the cutoff point for obesity as a BMI of >/=25 kg/m(2) instead of waist circumference. The genotypes for 25 polymorphisms in the coding region of the mitochondrial genome were determined, and the haplotypes were classified into 10 major haplogroups, i.e., F, B, A, N9a, M7a, M7b, G1, G2, D5, and D4. Multivariate logistic regression analysis revealed that the haplogroup N9a was significantly associated with resistance against metabolic syndrome in women with an odds ratio (OR) of 0.21 (95% CI 0.07-0.58, P = 0.0042). Women with haplogroups G1 and D5 tended to be resistant against metabolic syndrome with an OR of 0.22 (0.06-0.68, P = 0.0129) for G1 and with an OR of 0.32 (0.10-0.96, P = 0.0469) for D5, respectively. These results indicate that mitochondrial haplogroup N9a may be a protective factor against metabolic syndrome in Japanese women.  相似文献   
87.
A recent report indicated that a high prevalence of basal-like breast tumors (estrogen receptor [ER]-negative, progesterone receptor [PR]-negative, human epidermal growth factor receptor [HER] 2-negative, and cytokeratin 5/6-positive and/or HER1-positive) could contribute to a poor prognosis in African American women with breast cancer. It has been reported that Japanese women with breast cancer have a significantly better survival rate than other races in the USA. These findings suggest that breast cancers in Japanese women have favorable biological characteristics. To clarify this hypothesis, we conducted a cohort study to investigate the prevalence of intrinsic subtypes and prognosis for each subtype in 793 Japanese patients. This study revealed a very low prevalence (only 8%) of basal-like breast tumors with aggressive biological characteristics in Japanese patients. Survival analysis showed a significantly poorer prognosis in patients with basal-like tumors than in those with luminal A tumors (ER- and/or PR-positive, and HER2-negative) with favorable biological characteristics. These findings support the hypothesis that breast cancers in Japanese women have more favorable biological characteristics and a better prognosis than those in other races. In conclusion, the prevalence of basal-like breast tumors could influence the prognosis of breast cancer patients of different races. The prevalence of intrinsic subtypes should be taken into account when analyzing survival data in a multi-racial/international clinical study.  相似文献   
88.
Stereotactic ventralis intermedius (Vim) thalamotomy is effective for essential tremor (ET) of the limb, but the effect on the activity of the sensorimotor cortex is still unclear. The functional changes in this cortical area of patients with ET after Vim thalamotomy were investigated using functional magnetic resonance (fMR) imaging. Six patients underwent Vim thalamotomy for medically intractable ET, predominantly in the right hand. 1.5-tesla fMR imaging was performed using the blood oxygenation level-dependent sequence, before and after Vim thalamotomy, during passive movements with right wrist flexion and extension. Before and after images were analyzed using SPM99 software. Activation in the sensorimotor cortex and supplementary motor area evoked by wrist passive movement was observed both before and after surgery. Group analysis of changes in the blood oxygenation level-dependent response revealed a significantly smaller activated area postoperatively. Activation at the fundus of the central sulcus was characteristically decreased. All patients showed marked improvement in tremor after Vim thalamotomy. No patient experienced neurological deficits. fMR imaging showed that activation at the fundus of the central sulcus evoked by passive wrist movement was suppressed after Vim thalamotomy in ET patients, probably due to disruption of the thalamocortical pathway. The fundus of the central sulcus (Brodmann area 3a) is likely to be one of the key relays in the tremor circuit.  相似文献   
89.
OBJECTIVE: Stone analysis is an important examination for treatment and prevention of recurrence in urolithiasis. A twenty-six years clinical study of patient with urinary stone formers performed stone analysis was conducted. MATERIALS AND METHODS: 1,108 stone formers (male 726, female 382) who performed stone analysis from 1977 to 2002 was conducted. Location of the stone, sex, age, treatment and stone analysis was examined in this study. Phase 1 is from 1977 to 1983 mainly performed open surgery, phase 2 is from 1984 to 1992 mainly performed endoscopic surgery, and phase 3 is from 1993 to 2002 mainly performed extracorporeal shock wave lithotripsy (SWL). RESULTS: Analytic numbers per year increased, especially phase 3. In the treatment of upper urinary tract (UUT) stone, open surgery, endoscopic surgery and SWL was carried out 78.4%, 72.8% and 71.4% of all cases in each phase. Many transurethral lithotripsy were performed for lower urinary tract (LUT) stone. The numbers of UUT and LUT stone were 1,007 and 101 cases. The frequency of LUT stone was higher than that found in a nationwide urolithiasis survey carried out in Japan in 1995. The male-female ratio of UUT stone was 2.35:1, 1.74:1 in phase 2 and 3. The frequency of female increased in phase 2 more than that in phase 3. The incidence of calcium oxalate stone was increased, calcium phosphate stone and infectious stone was significantly decreased in UUT and calcium containing stone in LUT was decreased. The average age for incidence of UUT stone rose in man step by step. The frequency in male was significantly higher than that in female under 50's, not significantly higher over 50's in calcium oxalate with calcium phosphate stone former (p = 0.009). CONCLUSION: In the present study, the clinical features were as follows : important urinary stone analysis, high frequency of LUT stone, high frequency in females, tendency to aging, high frequency of calcium containing stone in LUT, resolution of the difference in male and female over 50's in calcium oxalate with calcium phosphate stone former.  相似文献   
90.

Background

Crush syndrome (CS) has been reported in disasters, terrorist incidents, and accidents, and the clinical and pathologic picture has gradually been clarified. Few lethal and reproducible animal models of CS with use of a quantitative load are available. A new model is needed to investigate pathologic and therapeutic aspects of this injury.

Materials and methods

Using a device built from commercially available components, both hindlimbs of anesthetized rats were respectively compressed for 6 h using 3.6-kg blocks. The effects of trunk warming alone without compressed hindlimbs (Group A), non-warming at room temperature (Group B), whole-body warming including compressed hindlimbs (Group C), or warming of compressed hindlimbs alone (Group D) during compression were examined. Survival rates were compared and hematological and histologic analyses were performed at specific time points after compression release.

Results

Limb or whole-body warming significantly worsened the survival of rats. We found a much lower survival rate of 0%–10% in animals, in which the hindlimbs were warmed during compression (Groups C and D) at 12 h after compression release, compared with 90%–100% in animals without warming of the hindlimbs (Groups A and B). Groups C and D showed significantly enhanced hyperkalemia at ≥4 h after compression release and all blood samples from dead cases showed hyperkalemia (>10 mEq/L).

Conclusions

We developed a new lethal and reproducible rat CS model with a quantitative load. This study found that warming of compressed limbs worsened the survival rate and significantly enhanced hyperkalemia, apparently leading to cardiac arrest.  相似文献   
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