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71.
Objective. To determine the correlation between water content and magnetization transfer (MT) ratio of the water component in normal bone marrow using gradient-echo (GRE) magnetic resonance (MR) imaging. Design. Three types of GRE sequence – using fat suppression, using a combination of MT and fat suppression techniques, and without MT or fat suppression – were performed in nine healthy subjects. The water content of bone marrow assessed with GRE imaging was compared with that assessed with MR spectroscopy in three cases. The correlation between water content and MT ratio was observed using GRE imaging in nine subjects. Results and conclusions. The water content as assessed by GRE imaging and by MR spectroscopy were closely correlated (P<0.005, r=0.932). An inverse correlation between water content and MT ratio was observed in normal bone marrow (P<0.03, r=–0.432), which suggests that the water component in bone marrow includes free water protons.  相似文献   
72.
BACKGROUND: Hemodialysis patients have advanced arterial wall stiffening as shown by increased aortic pulse wave velocity (PWV), an independent predictor of cardiovascular mortality. We compared aortic PWV of uremic patients before starting hemodialysis treatment with that of patients on maintenance hemodialysis. METHODS: The subjects were 71 patients with end-stage renal disease (ESRD) before starting hemodialysis (predialysis group), 144 patients on maintenance hemodialysis, and 140 healthy control subjects. These three groups were all nondiabetic and comparable in age and gender. RESULTS: The hemodialysis group had greater aortic PWV than the healthy subjects, and the predialysis patients showed a still higher value than the hemodialysis group. Multiple regression analysis in the total subjects revealed that the presence of renal failure was significantly associated with increased aortic PWV independent of age, gender, blood pressure, body mass index, smoking, high-density lipoprotein (HDL) and nonhigh-density lipoprotein (non-HDL) cholesterol levels. In contrast, hemodialysis was associated with decreased aortic PWV independent of renal failure and the other factors. Further analyses in the combined uremic patients again indicated the favorable impact of hemodialysis on aortic PWV independent of the classical risk factors, use of antihypertensive medications, including angiotensin-converting enzyme inhibitors and calcium channel blockers, hematocrit, serum calcium, phosphorus, parathyroid hormone levels, and the use of calcium carbonate. Insulin resistance using homeostasis model assessment (HOMA-IR) was associated with increased aortic PWV. CONCLUSION: Aortic stiffening was present in uremic patients before starting hemodialysis treatment and no adverse effect of hemodialysis was observed, suggesting the important roles of renal failure and/or metabolic alterations secondary to renal failure in arterial stiffness in patients with uremia.  相似文献   
73.
AIM: The aim of this study was to examine the cumulative risk of pouchitis following restorative proctocolectomy for UC and FAP in Japanese patients, and to assess the response to medical treatment and its outcome. PATIENTS AND METHODS: 521 patients with UC and 117 FAP patients underwent proctocolectomy and received a J-shaped IPAA at our department of surgery. We investigated these patients using PDAI for the diagnostic criteria of pouchitis. RESULTS: Pouchitis occurred in only 32 UC patients (6.1%). The cumulative risk of developing pouchitis for a UC patient was 7% at 5 years after and 12% at 10 years after surgery. The medical treatment of acute pouchitis was usually oral metronidazole (250 mg twice daily) for 2 weeks or oral ciprofloxacin (200 mg thrice daily) in patients who could not tolerate metronidazole. Single episodes of pouchitis occurred in 21 patients (65.6%) and chronic or frequent relapses of pouchitis in 11 patients (34.4%). Three patients (9.4%) required re-ileostomy. Two patients (6.3%) required pouch excision. There were no patients with complicated dysplasia. CONCLUSION: The cumulative risk of pouchitis in Japanese UC patients is lower than that of western countries.  相似文献   
74.
Spontaneous massive retroperitoneal hemorrhage from an adrenal tumor is rare and is usually fatal if unrecognized. We report a case of spontaneous rupture of a primary adrenocortical carcinoma that occurred in a 79-year-old man. He visited our hospital with left abdominal pain. Computed tomography (CT) showed a left retroperitoneal hemorrhage. We could not find the origin of this hemorrhage. Two months later, CT showed the left adrenal tumor, and left adrenalectomy and nephrectomy were performed successfully. The histological diagnosis was adrenocortical carcinoma. He rejected adjuvant therapy. Local recurrence of the tumor was found, and right adrenal gland, brain, and mediastinal lymph node metastases were recognized 6 months after the operation. He died 11 months after the operation.  相似文献   
75.

Purpose

This study was undertaken to elucidate the clinicopathological characteristics and surgical outcome of the periductal infiltrating (PI) type of intrahepatic cholangiocarcinoma (ICC), which is a distinct macroscopic type of ICC arising from the second-order of the intrahepatic bile ducts without apparent invasion of the surrounding liver parenchyma.

Methods

All patients with the PI type of ICC were identified from a database of patients with intrahepatic cholangiocellular carcinoma that underwent surgical resection between 1983 and 2009. The clinicopathological data of these patients were analyzed retrospectively.

Results

Sixteen of 203 patients (7.9%) had the PI type of ICC. The median survival was 7.7?years with 5-year survival rate of 62.1%. The PI type of ICC showed a significantly better survival than the mass-forming (MF) type (P?=?0.0293) or MF plus PI type of ICC (P?=?0.0001). Microscopic examinations showed intrahepatic metastasis to be absent in all the patients with PI type ICC. The incidence of intrahepatic metastases in patients with PI type was significantly lower in comparison to that of patients with MF type (P?=?0.0030) and MF plus PI type (P?=?0.0533), respectively.

Conclusion

Surgery could therefore provide a favorable outcome in patients with the PI type of ICC, probably due to its lower incidence of intrahepatic metastases.  相似文献   
76.
The prevalence of coronary artery disease in patients with aortic aneurysm is high. As an antecedent percutaneous coronary intervention with antiplatelet therapy may cause a rupture of aortic aneurysm, concomitant treatment for aortic arch aneurysm and coronary artery disease is recommended. We report a technique of a combined procedure of antegrade endovascular repair with aortic arch debranching and off-pump coronary artery bypass grafting.  相似文献   
77.
Accumulating evidence shows that estrogens participate in the pathogenesis and development of benign prostatic hyperplasia and prostate cancer by activating estrogen receptor α. In contrast, estrogen receptor β is involved in the differentiation and maturation of prostatic epithelial cells, and thus possesses antitumor effects in prostate cancer. However, the natural ligands of estrogen receptor β are not fully understood, and its mode of action according to its ligands and the binding sites located in the promoter regions of downstream genes remains to be elucidated. Here, we review recent experimental investigations of estrogen receptors and their urological relevance. Estrogen receptor‐mediated signaling in the prostate is essential together with the androgen receptor‐mediated pathway, providing a new therapeutic target for prostatic diseases.  相似文献   
78.

Purpose

A relatively high incidence of postoperative nausea and vomiting (PONV) occurs in patients undergoing laparoscopic cholecystectomy. This study was undertaken to compare the efficacy of granisetron-droperidol combination with each drug alone for the prevention of PONV after laparoscopic cholecystectomy.

Methods

In a randomized, double-blind manner, 150 female inpatients received 3 mg granisetron (Group G), 1.25 mg droperidol (Group D) or 3 mg granisetron plus 1.25 mg droperidol (Group GD) (n = 50 for each)iv immediately before the induction of anaesthesia. The same standard general anaesthetic technique, which consisted of isoflurane and nitrous oxide in oxygen, was used. Nausea, vomiting and safety assessments were performed continuously during the first 24 hr after anaesthesia.

Results

Complete response, defined as no PONV and no administration of rescue antiemetic medication, was 86% in Group G, 64% in Group D and 98% in Group GD (P = 0.03 vs Group G,P = 0.001 vs Group D). No clinically adverse events were observed in any group.

Conclusion

Granisetron-droperidol combination is more effective than each antiemetic alone in the prevention of PONV after laparoscopic cholecystectomy.  相似文献   
79.
BACKGROUND: Abdominal aortic aneurysms (AAAs) are characterized by histologic signs of chronic inflammation, destructive remodeling of extracellular matrix, and depletion of vascular smooth muscle cells. We investigated the process of extracellular matrix remodeling by performing a genetic association study with polymorphisms in the genes for matrix metalloproteinases (MMPs), tissue inhibitors of metalloproteinases (TIMPs), and structural extracellular matrix molecules in AAA. Our hypothesis was that genetic variations in one or more of these genes contribute to greater or lesser activity of these gene products, and thereby contribute to susceptibility for developing AAAs. METHODS: DNA samples from 812 unrelated white subject (AAA, n = 387; controls, n = 425) were genotyped for 14 polymorphisms in 13 different candidate genes: MMP1(nt-1607), MMP2(nt-955), MMP3(nt-1612), MMP9(nt-1562), MMP10(nt+180), MMP12(nt-82), MMP13(nt-77), TIMP1(nt+434), TIMP1(rs2070584), TIMP2(rs2009196), TIMP3(nt-1296), TGFB1(nt-509), ELN(nt+422), and COL3A1(nt+581). Odds ratios and P values adjusted for gender and country of origin using logistic regression and stratified by family history of AAA were calculated to test for association between genotype and disease status. Haplotype analysis was carried out for the two TIMP1 polymorphisms in male subjects. RESULTS: Analyses with one polymorphism per test without interactions showed an association with the two TIMP1 gene polymorphisms (nt+434, P = .0047; rs2070584, P = .015) in male subjects without a family history of AAA. The association remained significant when analyzing TIMP1 haplotypes (chi 2 P = .014 and empirical P = .009). In addition, we found a significant interaction between the polymorphism and gender for MMP10 ( P = .037) in cases without a family history of AAA, as well as between the polymorphism and country of origin for ELN ( P = .0169) and TIMP3 ( P = .0023) in cases with a family history of AAA. CONCLUSIONS: These findings suggest that genetic variations in TIMP1, TIMP3, MMP10, and ELN genes may contribute to the pathogenesis of AAAs. Further work is needed to confirm the findings in an independent set of samples and to study the functional role of these variants in AAA. It is noteworthy that contrary to a previous study, we did not find an association between the MMP9 (nt-1562) polymorphism and AAA, suggesting genetic heterogeneity of the disease. CLINICAL RELEVANCE: Abdominal aortic aneurysms (AAAs) are an important cardiovascular disease, but the genetic and environmental risk factors, which contribute to individual's risk to develop an aneurysm, are poorly understood. Histologically, AAAs are characterized by signs of chronic inflammation, destructive remodeling of the extracellular matrix, and depletion of vascular smooth muscle cells. We hypothesized that genes involved in these events could harbor changes that make individuals more susceptible to developing aneurysms. This study identified significant genetic associations between DNA sequence changes in tissue inhibitor of metalloproteinase 1 (TIMP1), TIMP3, matrix metalloproteinase 10 (MMP10) and elastin (ELN) genes, and AAA. The results will require confirmation using an independent set of samples. After replication it is possible that these sequence changes in combination with other risk factors could be used in the future to identify individuals who are at increased risk for developing an AAA.  相似文献   
80.
Cardiac metastatic liposarcoma is a rare tumor. We report a case of successful resection of a cardiac metastatic liposarcoma extending into the superior vena cava (SVC), right atrium, and right ventricle. Using cardiopulmonary bypass (CPB) by venous cannulation of the upper portion of the SVC and inferior vena cava (IVC), the intracardiac tumor was completely resected. Surgical resection with the addition of radiotherapy prolonged the patient's life.  相似文献   
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