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71.
BACKGROUND: Although knowledge of cancer invasion of the portal bifurcation is vitally important in planning an operation for perihilar cholangiocarcinoma, the diagnostic capability of multidetector-row computed tomography (MDCT) for this purpose has not been assessed. We evaluated how well MDCT could identify cancer invasion of the portal bifurcation by perihilar cholangiocarcinoma. METHODS: Between April 2003 and June 2005, perihilar cholangiocarcinoma was resected in 87 patients, 83 of whom underwent MDCT within 1 month before the surgery. Three-dimensional volume-rendered (3DVR) and multiplanar reformation (MPR) images were examined for evidence of portal vein invasion. Agreement with intraoperative and pathologic findings was assessed. Portal bifurcation findings by 3DVR and MPR were classified into no portal vein stenosis, unilateral stenosis, or more extensive stenosis, and also into tumor contact with the bifurcation in no, one of two, or two projections. RESULTS: For macroscopic portal vein invasion, sensitivity, specificity, positive predictive value, negative predictive value, and overall accuracy were 81.5, 91.1, 81.5, 91.1, and 88.0% in 3D portography and 96.3, 92.6, 86.7, 98.1, and 94.0% in MPR, respectively. Findings by both 3DVR and MPR were significantly correlated with depth of cancer invasion (p < 0.001). CONCLUSION: MDCT is useful in assessing cancer invasion of the portal vein bifurcation by perihilar cholangiocarcinoma.  相似文献   
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We investigated the possibility of articular cartil-age distraction for use in reconstructing joint structure and for increasing the donor site of osteochondral grafts. Intraarticular osteotomy was performed at the femoral condyle in 12 Japanese white rabbits. The bone segment was fixed with a specially designed external fixator. After a 3-week waiting period, distraction was performed intermittently for 3 weeks (0.7 mm × 3 times per week) in the distraction group (n = 7) and, in the remaining animals (gap group; n = 5), a gap of 6.3 mm in length was made at surgery. All rabbits received etidronate injections (20 mg/kg ×2 times per week) for 5 weeks, to slow mineralization. The femoral condyle was harvested 9 weeks postoperatively and decalcified sagittal sections were stained and evaluated, using a histological grading scale. In the distraction group, distraction of 4.2 ± 1.4 mm was achieved, and the distracted cartilage area was filled with regenerated cartilage, without any gap between the regenerated and the adjacent articular cartilage. This regenerated cartilage showed metachromasia with toluidine blue. In the gap group, newly formed cartilage tissue was folded from the edge of the osteotomy site and fibrous tissue was interposed in the gap. The histological grading score was significantly lower in the distraction group (P < 0.02). Our preliminary results demonstrated the possibility of cartilage distraction; however, long-term observation will be necessary to confirm the characteristics of the distracted cartilage. We may call the process "distraction arthrogenesis", because the entire articular entity, which consists of cartilage, subchondral bone, and bone, could be distracted at once. Received: April 5, 2001 / Accepted: July 15, 2001  相似文献   
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Epithelioid angiomyolipoma has malignant potential; however, no effective therapy has been established for advanced cases. A 50‐year‐old woman with a history of right nephrectomy for epithelioid angiomyolipoma was referred to our institution. Computed tomography and magnetic resonance imaging showed multiple tumors in her lung, liver and pelvic cavity. The liver and pelvic tumor specimens obtained by needle biopsy confirmed the diagnosis of epithelioid angiomyolipoma recurrence. The patient was treated with everolimus (10 mg/day). Three months later, pulmonary lesions disappeared; liver and pelvic tumors significantly shrank in size, but the pelvic tumor gradually enlarged again. We carried out surgical resection of the residual liver and pelvic cavity tumors. Although the mammalian target of rapamycin inhibitor seems to be effective for treating epithelioid angiomyolipoma, its long‐term effects remain unknown. Thus, aggressive administration of a multidisciplinary treatment including molecular target therapy and surgical resection is required to improve the prognosis of epithelioid angiomyolipoma.  相似文献   
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Tsutomu  Ohtsuka  MD    Akira  Hasegawa  MD    Akihiko  Nakano  MD    Akio  Yamakage  MD    Mary  Yamaguchi  MD  Yoshiki  Miyachi  MD 《International journal of dermatology》1997,36(2):116-122
Background Patients with systemic sclerosis (SSC) show a capillary abnormality of nailfolds with controversial correlation with organ involvement. Our purpose was to study the correlation between this nailfold capillary abnormality and pulmonary hypertension in patients with SSC. Methods We studied the nailfold capillaries, using capillary microscopy, and the pulmonary arterial pressure, using right-heart catheterlzation, in 44 patients with SSC. Canonical discriminant analysis was used to define the capillary abnormality in patients with SSC, which was then compared with that of 40 normal controls. The correlations between the patterns of nailfold capillaries and the cardiopulmonary findings. Including the pulmonary arterial pressure, were examined using Fisher's test. Results Thirty-two of 44 patients with SSC could be differentiated from normal controls by our definition of the SSC pattern. The SSC pattern correlated significantly with elevated pulmonary vascular resistance, as well as with pulmonary fibrosis, eiectrocardiographic abnormalities, decreased vital capacity, and decreased diffusing capacity for carbon monoxide. All SSC patients with pulmonary hypertension showed this SSC pattern. In patients with elevated pulmonary arterial pressure, capillary microscopy and diffusion capacity for carbon monoxide (DCCM) showed the highest rate of abnormalities. A limited-type SSC significantly correlated with DCCM and with anticentromere antibody, and the diffuse-type SSC with pulmonary fibrosis and anti-sci-70 antibody. Conclusion Our data suggest that in patients with SSC, nailfold capillary abnormalities correlate with pulmonary arterial hypertension as well as with clinical and laboratory findings indicating pulmonary hypertension.  相似文献   
76.
Eosinophilic pustular folliculitis (EPF), also known as Ofuji's disease, is an inflammatory dermatosis that was first described in Japan in 1970. More than 300 cases have been reported so far, and 113 Japanese cases have been reported in Japan since 1980. To comprehend the characteristics of Japanese EPF cases, we classified these cases into three types: classic, immunosuppression‐associated (IS‐EPF), and infancy‐associated (I‐EPF). Trends in age of onset and in distribution and characterization of eruptions differed between the types. We found 91 cases of classic EPF (mean age, 39.7 years), consisting of 66 males (73%) and 25 females (27%), in most of which eruptions primarily affected the face; 18 cases of IS‐EPF (44.2 years), consisting of 15 males (83%) and three females (17%), in which eruptions affected the face less predominantly; and four cases of I‐EPF (7.0 years), consisting of two males (50%) and two females (50%), primarily affecting the scalp. The number of IS‐EPF cases has increased since the late 1990s, reflecting the increasing number of HIV‐positive patients in Japan. Systemic non‐steroidal anti‐inflammatory drugs were effective in more than 70% of cases. Dimethyl diphenyl sulfone, antibiotics including minocycline, psoralen plus ultraviolet A therapy and ultraviolet B treatments worked in some cases. Topical steroids and tacrolimus were also effective in some cases of EPF, while topical indomethacin was less effective.  相似文献   
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Early-onset sarcoidosis (EOS) and inheritable Blau syndrome (BS) share characteristic clinical features of juvenile-onset systemic granulomatosis syndrome that mainly affects skin, joints, and eyes. However, no direct evidence has been shown for the possible common origin of these 2 diseases. Recent discovery of CARD15 mutations in BS families encouraged us to investigate similar CARD15 mutations in EOS patients. Among 10 EOS cases retrospectively collected in Japan, heterozygous missense mutations were found in 9 cases; 4 showed a 1000C>T (R334W in amino acid change) that has been reported in BS, 4 showed novel 1487A>T (H496L), 1538T>C (M513T), 1813A>C (T605P), and 2010C>A (N670K), and 1 case showed double 1146C>G (D382E)/1834G>A (A612T) mutations on different alleles. All 6 of these variants of CARD15 showed increased basal nuclear factor (NF)-kappaB activity. These findings indicate that the majority of EOS and BS cases share the common genetic etiology of CARD15 mutations that cause constitutive NF-kappaB activation.  相似文献   
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