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Background: The accessory pancreatic duct (APD) sometimes is developmentally obliterated near the duodenum. We evaluated patency of the minor duodenal papilla by dye‐injection endoscopic retrograde pancreatography to determine whether patency was related to papillary size and location. Methods: We injected 2–3 mL of contrast material containing indigocarmine into the main pancreatic duct via an endoscopic catheter in 104 patients. It was endoscopically observed whether dye was extruded from the minor papilla. Size of the minor papilla and distance from the orifice of the major duodenal papilla to the apex of the minor papilla were measured endoscopically with measuring forceps. Results: The APD was patent in 56 of 104 cases (54%). Size of the minor papilla varied considerably from 3 to 6 mm, but showed no correlation with patency. Half of the patients with chronic pancreatitis (6/13) had the minor papilla larger than 6 mm. In cases where the terminal APD had a cudgel or tapering‐off configuration, the minor papilla was larger than in cases where the duct had a stick shape. The minor papilla was patent in 9 out of 10 cases (90%) when it was near the major papilla (≤ 1.5 cm). Frequency of a patent minor papilla was 16 out of 33 (48%) when it existed 1.5 to 2.0 cm from the major papilla, and 31 out of 61 (51%) when the distance was more than 2.0 cm. Conclusions: The minor papilla was more frequently patent when it was close to the major papilla (P < 0.05).  相似文献   
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In this study, we evaluated the potential of (99m)Tc-hexakis-2-methoxyisobutylisonitrile (MIBI) for detecting bone metastases in comparison with a conventional bone tracer. METHODS: (99m)Tc-MIBI and (99m)Tc-hydroxymethylene diphosphonate (HMDP) scans were obtained from 99 patients with proven malignant diseases and suspected bone metastases. We compared 373 lesions that showed abnormal uptake on (99m)Tc-MIBI scans or (99m)Tc-HMDP scans (or both). RESULTS: Bone metastases were confirmed in 334 of 373 lesions. Thirty-nine lesions on (99m)Tc-HMDP scans had false-positive findings, but only 2 of these lesions had false-positive findings on (99m)Tc-MIBI scans. (99m)Tc-MIBI and (99m)Tc-HMDP scans were equivalent in 168 of 334 lesions (50.3%). (99m)Tc-MIBI scans correctly detected more lesions than (99m)Tc-HMDP scans: 284 lesions (85.0%) versus 218 lesions (65.3%) (P < 0.005), respectively. (99m)Tc-MIBI scans showed a markedly higher sensitivity for detecting metastases in the femur and humerus compared with (99m)Tc-HMDP scans: 97 of 98 lesions (99.0%) versus 35 of 98 lesions (35.7%) (P < 0.005) and 21 of 22 lesions (95.5%) versus 11 of 22 lesions (50.0%) (P < 0.005), respectively. (99m)Tc-HMDP scans of 17 patients showed no abnormal images. However, (99m)Tc-MIBI scans correctly detected bone metastases, and subsequent development of multiple lesions was observed on follow-up (99m)Tc-HMDP scans of 15 patients. (99m)Tc-MIBI scans were superior to (99m)Tc-HMDP scans in the detection of metastases attributed to breast cancer, multiple myeloma, and hepatoma. On the contrary, (99m)Tc-MIBI scans were less sensitive than (99m)Tc-HMDP scans for detecting bone metastases attributed to prostate cancer in the other skeletal sites except for femur and humerus. CONCLUSION: (99m)Tc-MIBI scans have better sensitivity for detecting bone metastases and provide more specific complementary findings than conventional bone scans. (99m)Tc-MIBI accumulation attributed to bone marrow metastases may occur at an early stage, before the bone remodeling process in the surrounding bone can be detected on conventional bone scans.  相似文献   
54.
Background Embryologically, the pancreatic duct system develops by the fusion between the dorsal and ventral pancreatic bud ducts. It has been suggested that the proximal part of the main dorsal pancreatic duct partially regresses to form the accessory pancreatic duct (APD). Aim of this study was to clarify the anatomy of the pancreatic duct system of the head of the pancreas and investigate the embryology of the normal pancreatic duct system. Methods We reviewed endoscopic retrograde pancreatography of normal pancreatic heads (n = 256) and pancreas divisum (n = 36), focusing on long inferior branches arising from the APD and the main pancreatic duct (MPD). The accessory pancreatograms were divided into two patterns of course and shape, the long type (171 cases) and the short type (85 cases) according to the length of the MPD from the orifice to the junction with the APD. The long-type APD formed a straight line and joined the MPD at the neck portion of the pancreas. The short-type APD joined the MPD near its first inferior branch. Results The shape of the long-type APD was quite similar to that of the dorsal pancreatic duct of pancreas divisum. The short-type APD was less likely to have a long inferior branch arising from the APD. The length of the APD from the orifice to the first long inferior branch was similar in the long-type APD (19.4 ± 4.0 mm) and in the short-type APD (18.8 ± 4.2 mm). The first long inferior branch from the long-type APD passed though the MPD near the origin of the inferior branch from the MPD, whereas the short-type APD joined the MPD near its inferior branch. Conclusions There are two types of APD. The long-type APD was quite similar to the shape of the dorsal pancreatic duct of pancreas divisum, and seems to represent a continuation of the main duct of the dorsal pancreatic bud. The short-type APD was less likely to have a long inferior branch, and seems to be formed by the most proximal part of the main duct of the dorsal pancreatic bud and its long inferior branch.  相似文献   
55.
BACKGROUND: To investigate relationships between phenotypes and genotypes is not simple. We propose a phenotype-to-genotype screening strategy and pooled DNA system. As a pilot study of this strategy, we used arbitrarily primed polymerase chain reaction (AP-PCR) in combination with single-stranded DNA conformation polymorphism (SSCP) to screen for genetic polymorphisms associated with longevity. METHODS: Study subjects were separated into 3 age groups, individuals aged >100 years, 90-99 years and 60-69 years. Genomic DNAs were prepared from each individual, pooled to represent the 5 study groups, and then the pooled genomic DNAs were subjected to AP-PCR-SSCP analysis. RESULTS: We found 1 SNP more frequently in senior citizens with longevity. The genotype frequency of the 82133G>A polymorphism of human chromosome 3 clone RP11-61K12 (AC011199) differed significantly (P=0.0189, Fisher's exact test) between older subjects (>90 years) and younger subjects (<70 years). It is noteworthy that the strategy we describe herein was useful for identifying an SNP that showed statistically significant differences in its distribution across the subject groups. CONCLUSIONS: The pooled DNA strategy and quantitative genotype discrimination can also be applied to screening for the relationship between phenotype and genotype more effectively.  相似文献   
56.
Purpose We aimed to identify the electrical stimulation sites of pacemaker leads using a tissue tracking method of tissue Doppler imaging. Methods The study group consisted of 30 patients who had undergone permanent pacemaker implantation. During tissue Doppler imaging, the initial contraction site was seen as a red area stimulated by the pacemaker lead. This red area was analyzed precisely using time–distance curves generated by tissue tracking. Results The initial contraction site of the myocardium was located in the interventricular septum in seven patients and in the apical portion of the right ventricle in 11 patients. Furthermore, analysis of time–distance curves demonstrated that one point within the red area started to move earlier than the others. Conclusion The site of electrical stimulation within the myocardium can be determined from the time–distance curves generated by the tissue tracking method. A summary of this paper was presented at the 77th Conference of the Japan Society of Ultrasonics in Medicine (Tochigi, April 2004)  相似文献   
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59.

Background/Aims

Diffuse or segmental irregular narrowing of the main pancreatic duct (MPD), as observed by endoscopic retrograde cholangiopancreatography (ERCP), is a characteristic feature of autoimmune pancreatitis (AIP).

Methods

ERCP findings were retrospectively examined in 40 patients with AIP in whom irregular narrowing of the MPD was detected near the orifice. The MPD opening sign was defined as the MPD within 1.5 cm from the orifice being maintained. The distal common bile duct (CBD) sign was defined as the distal CBD within 1.5 cm from the orifice being maintained. Endoscopic findings of a swollen major papilla and histological findings of specimens obtained from the major papilla were examined in 26 and 21 patients, respectively.

Results

The MPD opening sign was detected in 26 of the 40 patients (65%). The distal CBD sign was detected in 25 of the 32 patients (78%), which showed stenosis of the lower bile duct. The patients who showed the MPD opening sign frequently showed the distal CBD sign (p=0.018). Lymphoplasmacytic infiltration, but not dense fibrosis, was histologically detected in biopsy specimens obtained from the major papilla.

Conclusions

On ERCP, the MPD and CBD adjacent to the major papilla are frequently maintained in patients with AIP involving the pancreatic head. These signs are useful for diagnosing AIP on ERCP.  相似文献   
60.
Ductal and acinar differentiation in pancreatic endocrine tumors   总被引:5,自引:0,他引:5  
Rare pancreatic endocrine tumors consisting of both exocrine and endocrine components have been reported sporadically. We investigated the ductal and acinar differentiation in pancreatic endocrine tumors. In immunohistochemical studies of 28 pancreatic endocrine tumors, staining with anti-carcinoembryonic antigen (CEA) or CA19-9 antibody indicated ductal differentiation, while staining with anti-amylase or anti-trypsin antibody indicated acinar differentiation. K-ras gene mutations and p53 gene alterations also were studied. Ten tumors were immunoreactive for CEA or CA19-9. Five tumors diffusely immunoreactive for CEA or CA19-9, in addition to endocrine markers, were diagnosed as duct–endocrine cell tumors of the pancreas. Two tumors diffusely immunoreactive for CEA or CA19-9 and also for pancreaticogut hormones as well as endocrine markers were diagnosed as duct–acinar–endocrine cell tumors. These tumors showed uniform histologic features and synchronous ductal, acinar, and endocrine differentiation, distinct from the coexisting different cellular populations seen in collision tumors. All tumors were malignant. These duct–endocrine cell tumors or duct–acinar–endocrine cell tumors of the pancreas may be derived from a stem cell that retains the capability of expressing either an exocrine or endocrine phenotype. Only one K-ras gene mutation and no p53 gene alterations were detected in these tumors, which suggests that they constitute an entity with a different origin than ductal carcinomas.  相似文献   
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