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111.
We determined the relationship between the site of rotator cuff tears and atrophy of the cuff muscles. 28 shoulders (28 patients) had rotator cuff tears: 19 isolated tears of the supraspinatus tendon (isolatedtear group) and 9 combined tears of the supraspinatus and infraspinatus tendons (combined-tear group). The cross-sectional area of the subscapularis, supraspinatus, the infraspinatus and teres minor muscles in the coronal oblique MR images were measured before and after surgery. Although we found no difference in tear size, the cross-sectional areas of the muscles were smaller in the combined-tear group than in the isolated-tear group. We conclude that atrophy of the supraspinatus and infraspinatus muscles also depends on the site of the tear.  相似文献   
112.
Proto  AV 《Radiology》1992,183(3):593
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113.
AIMS: We assessed changes in gene expression of hypertrophied liver after portal vein ligation (PL) in a test group of rats compared to a control group, which had the same size liver but no PL. METHODS: The portal veins of the left and median lobes in the test group were ligated in an initial operation. Four days after the PL, the liver volume of the posterior caudate lobe (5%) increased two-fold and comprised 10% of the liver. A 90% hepatectomy was then performed, leaving only the hypertrophied posterior caudate lobe, and leaving the normal anterior and posterior caudate lobes (10%) in the control (sham) group. A comparison of the expression profiles between two groups was performed using cDNA microarrays and the hepatic ATP level was measured. RESULTS: The survival rate for the PL group was significantly higher than for the sham group at 4 days after the hepatectomy (56.3% and 26.7%, P < 0.05). Gene expression of cyclin D1, proliferating cell nuclear antigen, cyclin A and B was upregulated, and the cyclin-dependent kinase inhibitor was downregulated. Increases were observed in: (i) pyruvate dehydrogenase, the tricarboxylic acid cycle cycle regulator, (ii) acyl-CoA dehydrogenase, the oxidation regulator, and (iii) cytochrome oxidases, the oxidative phosphorylation regulator. Hepatic ATP concentration after hepatectomy was better maintained in the PL group than in the sham group (0.48 +/- 0.01 micromol/ml vs. 0.33 +/- 0.01 micromol/ml, P < 0.05). CONCLUSION: The regenerating liver increased tolerance for extended hepatectomy compared to normal liver. It is believed that this is because the induced rapid regeneration of the remaining liver after hepatectomy increases ATP metabolism.  相似文献   
114.
This case report discusses the unusual presentation and ultrasound features of a solitary fibrous tumour of the face. Solitary fibrous tumour is an uncommon form of soft tissue tumour which, although seen predominantly within the lung pleura, can occur throughout the body in sites such as the peritoneum, mediastinum and head and neck. Ultrasound is an excellent imaging modality in the assessment of soft tissue masses in the head and neck. The ultrasound features demonstrated by this example of solitary fibrous tumour are reviewed. This report also highlights that ultrasound alone is ultimately limited in reaching a definitive diagnosis. The roles of other investigations such as ultrasound-guided biopsy and cross-sectional imaging are discussed.  相似文献   
115.
BackgroundThe true prognostic factors for induced medical abortion are unknown. We sought to investigate the effects of a patient's obstetric parameters on the induction–abortion interval in second-trimester medical abortion.Study DesignWe studied 216 consecutive women. Pregnancy was terminated with cervical preparation using osmotic dilators followed by 1 mg vaginal gemeprost administered every 3 h for a maximum of five doses in the first 24 h. All variables are expressed in categorical form (parity, gestational age, maternal age and body mass index) and analyzed by the Cox proportional hazards model.ResultsParity ≥3 was associated with a shorter duration of the induction–abortion interval (adjusted hazards ratio 1.96; 95% confidence interval 1.13–3.40). A gestational age ≥16 weeks was associated with a longer duration of the induction–abortion interval (0.71; 0.52–0.98). No significant association was found in maternal age and body mass index.ConclusionsIn combination with osmotic dilators and gemeprost, gestational age and parity are independent factors that affected the induction to abortion interval of second-trimester medical abortion.  相似文献   
116.
Data on the distribution of beta thalassemia among over 6,000 Melanesians reveals a major difference in the carrier rates between populations in the malarious coastal regions of New Guinea and those living in the historically malaria-free Highlands. The island of Maewo in Vanuatu has a particularly high incidence of beta + thalassemia associated with a single restriction enzyme haplotype. Direct cloning into a plasmid vector and sequence analysis demonstrate that the mutation is a G to C transversion at position 5 of intron 1 of the beta- globin gene. Oligonucleotide probe surveys indicate that this variant accounted for all cases of beta thalassemia studied from Maewo. It is also common in coastal Papua New Guinea where haplotype and oligonucleotide probe data suggest that the molecular basis of beta thalassmia is more heterogeneous.  相似文献   
117.
Because atherosclerotic plaque burden affects the likelihood of plaque rupture, it is important to determine the presence and extent of atherosclerotic plaque. We hypothesized that endothelial dysfunction becomes more prominent with development of atherosclerotic plaque; therefore, we examined the relation between coronary endothelial dysfunction and the presence of atherosclerotic plaque. In 36 patients with normal coronary arteries, acetylcholine (ACh; 3 and 30 μg/min) and nitroglycerin were infused into the left coronary ostium, and the diameter of the left anterior descending (LAD) coronary artery was quantitatively measured in response to each drug. The plaque burden was measured in the same segment using intravascular ultrasonography. The plaque burden was 31.2 ± 2.1% and correlated inversely with changes in coronary diameter induced by 3 μg/min of ACh (r = −0.754, p <0.0001), 30 μg/min of ACh (r = −0.552, P = 0.0005), and nitroglycerin (r = −0.531, P = 0.0009). Multivariate regression analysis showed that the change in coronary diameter induced by 3 μg/min of ACh was associated with plaque burden, independent of the effects of nitroglycerin-induced dilation. Receiver-operating characteristics analysis demonstrated that a cut-off value for the change in coronary diameter induced by 3 μg/min of ACh for predicting a plaque burden of>30% was 0%, with a sensitivity of 0.82 and a specificity of 0.95. These findings suggest that coronary endothelial dysfunction is correlated with atherosclerotic plaque burden, indicating that atherosclerotic plaque may be detected based on coronary endothelial function as assessed by low-dose ACh infusion.  相似文献   
118.
BACKGROUND/AIMS: Several surgical procedures from hilar bile duct resection to hepatectomy have been adopted for hilar cholangiocarcinoma. However the details of the surgical procedure and the indications for hilar bile duct resection have not been determined. METHODOLOGY: Pathohistological outcome of resected specimens in five patients undergoing extended hilar bile duct resection was reviewed and compared with 12 patients undergoing partial hepatectomy with caudate lobectomy. RESULTS: Extended hilar bile duct resection was used for older patients, cases of choledochal site and less invasive tumor. The mean lengths of the left hepatic duct (21.7 +/- 7.8 mm) and the anterior hepatic duct (18.0 +/- 3.2 mm) in the specimens resected by extended hilar bile duct resection did not differ from those seen in right and left hepatectomy, respectively. Furthermore, extended hilar bile duct resection removed partial caudal hepatic duct. However the length of the posterior hepatic duct removed by extended hilar bile duct resection (14.3 +/- 2.0 mm) was significantly less than that excised in left hepatectomy (19.3 +/- 6.6 mm) (P < 0.05). The histologic positive margin rate of the extended hilar bile duct resection group (40%) was the same as that of the hepatectomy group (50%). Papillary or nodular form tumor tended to have positive ductal margins in both surgical techniques. On the other hand, flat tumor tended to have high positive rates in both ductal and excisional margins even in hepatectomy. Two cases with positive surgical margin died of local recurrences, however another 3 cases with negative surgical margin are alive without recurrences from 8 to 20 months after surgery. CONCLUSIONS: The indication of extended hilar bile duct resection for hilar cholangiocarcinoma is limited to cases in which the infiltration is confined to the hepatic bifurcation, such as type I and type II of Bismuth classification with regard to papillary and nodular macroscopic appearance.  相似文献   
119.
The differential diagnosis between intracystic hemorrhage and cystadenocarcinoma of the liver is often difficult even with the use of various imaging modalities. A 73-year-old woman was admitted to our hospital with the complaint of right upper quadrant pain. Ultrasonography (US) demonstrated a heterogeneous echogenic cyst measuring 11 cm × 8 cm in size in S2 of the liver, indicated intracystic hemorrhage of simple liver cyst or cystadenocarcinoma, but the differential diagnosis was considerably difficult. Levovist (Schering, Berlin, Germany) US revealed no enhancement of the intracystic structures, suggesting a clot in the case of intracystic hemorrhage. An operation was performed and the resected lesion showed a solitary benign liver cyst, measuring 5.5 cm × 4.7 cm × 8.5 cm containing a large blood clot. The patient had an uneventful recovery after the surgery. Levovist US may play an important role in discrimination between intracystic hemorrhage of simple hepatic cysts and cystadenocarcinoma of the liver.  相似文献   
120.
BACKGROUND/AIMS: Major hepatectomy can now be successfully performed after portal vein embolization, but the effects of portal vein embolization have not been clearly delineated. Our objective is to examine whether portal vein embolization really contributes to the success of major hepatectomy. METHODOLOGY: Thirty-eight patients underwent portal vein embolization and hepatectomy of two subsegments or more. They all belonged to a high-risk group according to a prognostic score. We selected 9 of 38 patients with liver metastases (PE-meta group) and 32 patients who had undergone hepatectomy without portal vein embolization (non-PE-meta group) during the study period to compare the serum levels of total bilirubin after hepatectomy. Fifteen of 38 patients had the levels of polymorphonuclear leukocyte elastase and thrombin-antithrombin complex examined after hepatectomy (PE group) and so did 20 patients without portal vein embolization (non-PE group). RESULTS: The maximum levels of total bilirubin in non-PE-meta group correlated with the percentage of hepatic parenchyma to be resected. In the patients receiving portal vein embolization, the pre-PE and post-PE levels were both below the regression. Similar shifts were seen in the graphs of polymorphonuclear leukocyte elastase and thrombin-antithrombin complex. CONCLUSIONS: The effects of preoperative portal vein embolization on safety in major hepatectomy were proved by its suppression of rise in total bilirubin, polymorphonuclear leukocyte elastase and thrombin-antithrombin complex after hepatectomy.  相似文献   
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