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101.

Objectives

To investigate whether rice pads can eliminate lingering fat signals of the complex surface shape of both hands that occur with chemical shift selective (CHESS) at 1.5 T and 3.0 T.

Materials and methods

T1-weighted images were obtained with CHESS using 1.5 T and 3.0 T systems. The same imaging parameters were used with and without rice pads on the coronal plane of both hands in 10 healthy volunteers. The fat-suppression effects were classified into four categories and scored for images, and visual evaluations were performed by one radiologist and one radiologic technologist.

Results

At 1.5 T, the mean evaluation score was 1.55 for images obtained without rice pads and 3.50 for images obtained with rice pads. At 3.0 T, the mean evaluation score was 1.10 for images obtained without rice pads and 3.20 for images obtained with rice pads. With both systems, images obtained with the rice pads showed significantly better fat suppression effects than images obtained without rice pads (P < 0.0001, P < 0.0001).

Conclusions

It was confirmed that lingering fat signals are eliminated and good fat-suppressed images are obtained with the use of rice pads at 1.5 T and 3.0 T. Rice pads are therefore useful with at 1.5 T and 3.0 T, which are currently becoming more widely used.  相似文献   
102.
BACKGROUND AND PURPOSETo detect areas of cerebral perfusion from bypass arteries after vascular reconstruction, we administered selective intraarterial microsphere tracer into the external carotid arteries and determined (via single-photon emission computed tomography [IA-SPECT]) whether the distribution of radiotracer matched the arteriographic distribution of contrast material as shown on external carotid angiograms.METHODSWe compared the extent of regional distribution of tracer after external carotid artery injection of 20 to 40 MBq of 99mTc-HMPAO or 99mTc-ECD with that of contrast medium on the external carotid angiograms in 582 cortical regions in 12 patients with atherosclerotic occlusive disease and in 18 patients with moyamoya disease.RESULTSMarked accumulation of tracer was found only in the expected, specific, newly developed areas of cerebral perfusion from bypass arteries. The regional distribution of tracer corresponded to that of contrast medium in 523 regions (90%) and did not correspond in 59 regions (10%). Significant overestimation of the distribution of contrast material relative to that of tracer was observed in the patients with moyamoya disease.CONCLUSIONSPECT showed slightly different distribution of tracer from that predicted by conventional angiography. IA-SPECT should enhance the analysis of newly developed areas of cerebral perfusion from the bypass arteries.  相似文献   
103.
Objective: It is controversial whether or not surgery is beneficial for patients with non-small cell lung cancer accompanied by persistent lymph node metastasis in the mediastinum following induction therapy. We have therefore conducted a retrospective study to assess this issue Methods: Eligibility criteria were defined as follows: 1) the period of treatment was between January 1991 and April 1998, 2) the clinical stages were IIIA (N2) or IIIB (N3) with large lymph nodes (> or = 2 cm), 3) induction therapy had been administered, 4) tumor was resected completely, 5) at least one mediastinal lymph node had necrosis or scar if the pathological N status was p-N0 or p-N1 and 6) the p-stage was not IV. Dichotomous variables included the radiographic response of the tumor, the T status, and the N status. Results: Thirty-nine patients were eligible. There were 29 males and 10 females aged from 27 to 74 years, and involved 20 cases of adenocarcinoma. The pathological N status was as follows: p-N0 in 18 patients, p-N1 in 3, p-N2 in 16, and p-N3 in the other 2. In overall survival, the median survival time (MST) was 34 months and the actuarial 5-year-survival rate (5-YSR) was 28%. The group of patients with either N0 or N1 (n-21) had a 71-month MST and a 54% 5-YSR, and the group of patients with either N2 or N3 (n=18) had a 13-month MST and a 5-YSR of 0% (p<0.0001). On multivariate analysis, the pathological N factor was confirmed as an independently significant. Conclusions: Our retrospective study found that the survival rate of patients with persistent mediastinal nodal metastasis was very poor. A prospective study is needed to investigate whether or not surgery is beneficial for these patients.  相似文献   
104.
This study examined the role of mitogen-activated protein (MAP) kinase in PDGF-BB-induced proliferation and gene expression of human mesangial cells (MC). PDGF-BB stimulation of MC increased mRNA for transforming growth factor-beta1 (TGF-beta1), monocyte chemoattractant protein-1 (MCP-1), and plasminogen activator inhibitor-1 (PAI-1) and increased the cell numbers. To inhibit activation of extracellular signal-regulated kinase (ERK), c-Jun amino-terminal kinase (JNK), and p38, MC were infected with recombinant adenovirus containing dominant-negative mutants of ERK, JNK, and p38 (Ad-DN-ERK, Ad-DN-JNK, Ad-DN-p38, respectively), respectively. Infection of MC with Ad-DN-ERK or Ad-DN-JNK inhibited PDGF-BB-induced increase in [(3)H]thymidine incorporation and cell numbers, whereas Ad-DN-p38 did not. Ad-DN-ERK inhibited MCP-1 and PAI-1 mRNA expression in MC, but not TGF-beta1. Ad-DN-JNK and Ad-DN-p38 inhibited TGF-beta1 and MCP-1 mRNA expression, but not PAI-1. The inhibition of activator protein-1 (AP-1) in MC, by adenovirus containing dominant-negative mutant of c-Jun (Ad-DN-c-Jun), inhibited PDGF-BB-induced cell proliferation and TGF-beta1, MCP-1, and PAI-1 expressions. Furthermore, Ad-DN-JNK or Ad-DN-p38, but not Ad-DN-ERK, attenuated PDGF-BB-induced AP-1 activation in MC, indicating the involvement of JNK and p38 in AP-1 activation. Our results indicated that ERK and JNK, but not p38, participated in PDGF-BB-induced MC proliferation. PDGF-BB-induced expression of TGF-beta1 was mediated by JNK and p38, MCP-1 expression was through ERK, JNK, and p38, whereas PAI-1 expression was due to only ERK. AP-1 activation, which was partially due to JNK and p38 activations, was involved in MC proliferation and these three gene expressions. Thus, three MAP kinases seem to contribute to progression of glomerular disease via different molecular mechanisms.  相似文献   
105.
A 67-year-old man was referred to our hospital because of positive sputum cytology. Despite detailed examination, the malignant cell source remained elusive. Twenty months later, CT revealed two nodules in the right S1 and S10 regions which were resected. A year following the operation, gastoendoscopy showed a stomach tumor. Total gastrectomy with lymph node dissection was performed. Histologically, this patient was diagnosed with double primary lung cancer with metastasis to the stomach. The tumors of the lung, stomach and tumor cells in the sputum showed the same immunoreactivities of autocrine motility factor receptor (AMFR). In our institution, of 38 occult lung cancers encountered during the past 10 years, four (10.5%) occurred in the peripheral region. The presented four cases of radiologically occult lung cancer in the peripheral resion revealed bad prognosis, as three out of four patients were dead within 24 months after surgery. All of the four cases showed venous invasion, though the size of the primary tumor was small. Careful follow-up, including monitoring for distant metastasis, is necessary in radiologically occult peripheral lung cancer.  相似文献   
106.
Background  We evaluated the prognostic value of the preoperative serum carcinoembryonic antigen (CEA) level in patients with colorectal cancer (CRC). Patients and Methods  The study group comprised 638 patients. The optimal cutoff value for the preoperative serum CEA level was determined. Predictive factors of recurrence were evaluated using multivariate analyses. The relapse-free time was investigated according to the CEA level. Results  All patients underwent potentially curative resection for CRC without distant metastasis, classified as stage I, II, or III. The optimal cutoff value for preoperative serum CEA level was 10 ng/ml. Elevated preoperative serum CEA level was observed in 92 patients. Multivariate analysis identified tumor–node–metastasis (TNM) stage and preoperative serum CEA level as independent predictive factors of recurrence. The relapse-free survival between CEA levels >10 ng/ml and <10 ng/ml significantly differed in patients with stage II and III. However, there was no significant difference in relapse-free survival between CEA levels >10 ng/ml and <10 ng/ml in patients with stage I. Conclusion  Preoperative serum CEA is a reliable predictive factor of recurrence after curative surgery in CRC patients and a useful indicator of the optimal treatment after resection, particularly for cases classified as stage II or stage III.  相似文献   
107.
A dural tear is a common but troublesome complication of endoscopic spinal surgery. The limitations of space make repair difficult, and it is often necessary to proceed to an open operation to suture the dura in order to prevent leakage of cerebrospinal fluid. We describe a new patch technique in which a small piece of polyglactin 910 is fixed to the injured dura with fibrin glue. Three pieces are generally required to obtain a watertight closure after lavage with saline. We have applied this technique in seven cases. All recovered well with no adverse effects. MRI showed no sign of leakage of cerebrospinal fluid.  相似文献   
108.
AIM:To analyze the relationship between sperm mitochondrial membrane potential and sperm motility parameters by means of a computer-assisted sperm analyzer (CASA) and in-vitro fertilization rate(%FR). METHODS: Semen samples were obtained from 26 men undergoing in vitro fertilization-embryo transfer (IVF-ET). Informed consent was obtained from all men prior to the study. Samples were prepared using wash and swim-up method in HEPES-HTF medium. The sperm motility (%MOT), progressive motility (%PMOT), average path velocity (VAP) microm/s), straight line velocity (VSL) (micro m/s), curvilinear velocity (VCL) (microm/s) and %hyperactivated sperm (%HA), and the %FR were assessed. The samples were incubated in the presence of 2.0 mciromol/L of 5,5',6,6'-tetra-chloro-1,1',3,3'-tetraethylbenzimidazolyl-carbocyanine iodide (JC-1) for 30 min at 37 degrees C in air and washed in PBS before flow cytometry (FACSCalibur: Becton Dickinson) analysis. The mitochondrial probe JC-1 was used to identify the mitochondrial membrane potential. The sperm was divided into three populations according to the fluorescence pattern as follows: the high mitochondrial membrane potential group (n=8), the moderate group (n=5), and the low group (n=13). Statistical analysis was performed using unpaired t-test. RESULTS:Significant differences were found between the high and the low groups in %MOT (91.1+/-8.5 vs 63.0+/-32.7, mean+/-SD), VAP (73.0+/-14.2 vs 52.1+/-12.5), VCL (127.0+/-28.1 vs 87.0+/-22.6), %HA (27.3+/-23.6 vs 7.2+/-9.0) and %FR [73.2 (48/56) vs 59.0 (69/117)]. No significant differences were found in other CASA parameters. CONCLUSION: When the sperm mitochondrial membrane potential increases, sperm motility parameters and fertility potential will also increase. The JC-1 dye method is useful to predict sperm fertility potential.  相似文献   
109.
PURPOSE: We retrospectively assessed the surgical outcomes of nephron-sparing surgery (NSS) for patients with renal tumors. PATIENTS AND METHODS: From 1985 to March 2001, a total of 99 NSSs were performed on 94 patients with renal tumors. The patients were divided into three groups. Group I comprised of 22 patients who underwent imperative surgeries for renal cell carcinoma (RCC). The tumors were found in 18 patients bilaterally (including 8 patients with von Hippel-Lindau disease), in 3 with solitary kidney, and in 1 with chronic renal failure. The mean +/- standard deviation of patient age and tumor diameter was 46 +/- 23 years and 36 +/- 23 mm, respectively. Twenty-three in situ NSSs were performed on 18 patients in Group I, and the remaining 4 patients were treated with 3 simultaneous operations for bilateral renal tumors with or without 2 ex vivo surgeries. Group II consisted of 49 patients who had small RCCs with the normal contralateral kidney and underwent NSSs (elective indication). The mean age and tumor diameter was 54 +/- 10 years and 28 +/- 11 mm, respectively. Group III consisted of 23 patients with non-RCC tumor (10 angiomyolipomas, 8 cystic tumors, 2 adenomas, 2 metastatic tumors, and 1 degenerative lesion), all of whom were treated with NSS. The mean age and tumor diameter was 47 +/- 14 years and 41 +/- 29 mm, respectively. RESULTS: In Group I, 3 patients died of cancer including 2 patients who had had multiple lung metastases preoperatively. The five-year tumor specific survival rate was 87.3% with a postoperative follow-up of 49 +/- 36 months. In Group II, there were few peri-operative complications or no local recurrence at follow-up of 52 +/- 38 months. A patient developed lung metastasis, which was removed surgically with no evidence of recurrence at 159 months after NSS. Postoperative renal scintigraphy on 35 patients showed well-preserved renal function of the operated kidney. Improvement in surgical techniques resulted in less-invasive surgery in 22 operations during the last 4 years. The patients of Group III were also operated uneventfully, although 1 experienced postoperative bleeding. In 12 patients with solitary kidney (11 in Group I and 1 in Group III) serum creatinine level increased transiently, decreased to 1.3 times of preoperative values within 3 months, and almost recovered at 1-year follow-up. CONCLUSION: Excellent outcomes in cancer control and preservation of renal function support the validity of nephron-sparing surgery to treat renal tumors. The candidate patients may include those with bilateral kidney tumors, tumor occuring in the solitary kidney or small renal cell carcinomas with the normal contralateral kidney. Earlier detection of small lesions and less invasive surgical techniques will facilitate a wider indication of NSS.  相似文献   
110.
Objective: The diagnosis of small-sized (2 cm or less) non-small cell lung cancer (NSCLC) has increased with the development of computed tomography (CT), whereas unexpected extensive multiple-level mediastinal involvement has been occasionally detected in this small-sized lung cancer. To establish the optimal surgical strategy, we retrospectively analyzed the clinicopathologic features, efficacy of preoperative investigations and lobe specific patterns of nodal spread in small-sized NSCLC with mediastinal involvement. Methods: Among 1550 resected lung cancer cases between 1981 and 2000, 267 (17.2%) had peripheral small-sized NSCLC. Of these, 29 patients (10.8%) with mediastinal lymph node involvement who underwent pulmonary resection and systematic nodal dissection were reviewed. Results: Among 29 patients, 27 patients (93.1%) were adenocarcinoma, and 51.7% (15/29) showed no lymph node enlargement on CT (cN0). Surgical pathology revealed multiple-level mediastinal involvement in 65.5% (19/29) of all patients and 60.0% (9/15) of cN0 patients. All of right upper lobe tumors (n=11) showed multiple-level involvement. Thallium-201 single photon emission computed tomography (201Tl-SPECT) was positive for increased focal uptake in the mediastinum in 72.7% (8/11) of patients. Conclusions: The vast majority of cases were adenocarcinoma, and two thirds of them showed multiple-level mediastinal involvement, even in cN0 patients. We thus recommend to perform systematic nodal dissection or meticulous sampling for accurate intrathoracic staging, especially for right upper lobe tumor. 201Tl-SPECT appears to be more sensitive preoperative investigation for mediastinal metastasis compared with CT scan.  相似文献   
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