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Salivary duct carcinoma (SDC) is a distinctive and aggressive neoplasm. The most frequent site of origin is the parotid gland, followed by the submandibular gland. SDC originating in the minor salivary glands, particularly in the ectopic glands within the mandible, is extremely rare. We describe a 62-year-old man with SDC in the mandible, who presented with a painless lump in the right submandibular region (later identified as lymph node metastasis) and ipsilateral mental nerve palsy. Histologic examination after ablative surgery revealed SDC originating in the mandible and cervical nodal metastases spreading to levels I-III. The patient remains alive 59 months after presentation as a result of postoperative full-dose irradiation and regular intensive chemotherapy using TXT, 5-FU, and CDDP. However, the patient has local recurrence and distant metastases to the lung and brain. In this report, we also discuss the specific diagnostic criteria and developmental theories of intraosseous salivary gland tumors.  相似文献   
54.
Aims: We have previously reported 5-year follow-up data on the TIAregistry.org, an international prospective cohort in patients with transient ischemic attack (TIA) or minor stroke. We conducted a Japanese subgroup analysis because outcomes and predictors might differ according to ethnicities and regions. In this study, we compared the baseline and 5-year follow-up data of Japanese and non-Japanese patients with TIA or minor stroke. Methods: Patients with TIA or minor ischemic stroke within 7 days after the onset were classified into two groups based on ethnicity, Japanese ( n =345) and non-Japanese ( n =3502); further, 5-year event rates were compared between the two groups. We also determined predictors of 5-year stroke for both groups. Results: Vascular death and death from any cause were identified to be less prevalent, unlike stroke and intracranial hemorrhage, which was determined to be more prevalent in Japanese than in non-Japanese patients. Five-year rate of stroke was significantly higher in Japanese patients. Cumulative stroke and major cardiovascular event rates did not decline but instead linearly increased from 1 to 5 years in both groups. Baseline risk factors for 5-year stroke were as follows: age, diabetes, history of stroke or TIA, and congestive heart failure in Japanese patients. Independent predictors of 5-year stroke were large artery atherosclerosis, congestive heart failure, diabetes, and age in Japanese patients. Conclusions: Recurrent stroke and intracranial hemorrhage were determined to be more prevalent at 5 years after TIA or minor stroke in Japanese patients than in non-Japanese patients. Strategies to mitigate the long-term risks of stroke, aside from adherence to current guidelines, should take Japanese-patient-specific residual risks into account.  相似文献   
55.
Immunoglobulin A class antibody to hepatitis C virus core antigen (IgA anti-HCc) was measured in the serum of 128 patients with type C chronic liver disease. Fifty-eight patients (45.3%) were seropositive. IgA anti-HCc was detected in only one of 20 patients with chronic persistent hepatitis; however, 52.3% (46/88) of patients with chronic active hepatitis and 55% (11/20) of patients with liver cirrhosis were seropositive. Histological examination revealed that 22 (71.0%) of 31 patients with severe disease activity were seropositive compared to 35 (44.9%) of 78 patients with moderate (P<0.05) and one (5.3%) of 19 patients with mild (P<0.01) histological changes. IgA anti-HCc was measured sequentially in 65 patients who underwent interferon therapy. There was a significant difference between responders and other patients in the mean ratio of IgA anti-HCc titers one month after therapy. Three months after therapy, IgA anti-HCc was detectable in only two of 15 responders who were IgA anti-HCc seropositive at the start of therapy. In contrast, IgA anti-HCc reappeared three months after therapy despite a temporary decrease to undetectable levels in all nonresponders. We conclude that IgA anti-HCc is a useful marker to identify the presence of active type C liver disease and that the disappearance of IgA anti-HCc three months after interferon therapy predicts a good response in treated patients.  相似文献   
56.
Oncolytic herpes simplex virus type 1 (HSV-1) vectors are promising therapeutic agents for cancer. Their efficacy depends on the extent of both intratumoral viral replication and induction of a host antitumor immune response. To enhance these properties while employing ample safeguards, two conditionally replicating HSV-1 vectors, termed G47Delta and R47Delta, have been constructed by deleting the alpha47 gene and the promoter region of US11 from gamma34.5-deficient HSV-1 vectors, G207 and R3616, respectively. Because the alpha47 gene product is responsible for inhibiting the transporter associated with antigen presentation (TAP), its absence led to increased MHC class I expression in infected human cells. Moreover, some G47Delta-infected human melanoma cells exhibited enhanced stimulation of matched antitumor T cell activity. The deletion also places the late US11 gene under control of the immediate-early alpha47 promoter, which suppresses the reduced growth properties of gamma34.5-deficient mutants. G47Delta and R47Delta showed enhanced viral growth in a variety of cell lines, leading to higher virus yields and enhanced cytopathic effect in tumor cells. G47Delta was significantly more efficacious in vivo than its parent G207 at inhibiting tumor growth in both immune-competent and immune-deficient animal models. Yet, when inoculated into the brains of HSV-1-sensitive A/J mice at 2 x 10(6) plaque forming units, G47Delta was as safe as G207. These results suggest that G47Delta may have enhanced antitumor activity in humans.  相似文献   
57.
The aim of this study was to compare the effects of a calcium antagonist, nicardipine SR, with an angiotensin-converting enzyme (ACE) inhibitor, alacepril, on the regression of left ventricular hypertrophy (LVH) and function. Twenty patients with LVH, aged 42–73 years, were treated with nicardipine SR or alacepril. Ten patients were treated with nicardipine SR (40–80 mg) for 21 months, and the other 10 patients were treated with alacepril (25–100 mg) for 18 months. All patients underwent echocardiography to assess left ventricular structure and function before and after the treatment. After nicardipine SR or alacepril treatment, blood pressure was decreased significantly from 176.0 ± 13.9/97.0 ± 5.3 mmHg to 140.0 ± 14.0/77.4 ± 7.2 mmHg and from 168.2 ± 22.3/99.0 ± 5.5 mmHg to 138.4 ± 12.5/85.2 ± 9.7 mmHg, respectively (both p < 0.01), whereas heart rate did not change (73.8 ± 14.6 beats/min vs. 69.9 ± 13.5 beats/min and 71.6 ± 9.7 vs. 65.8 ± 8.1 beats/min, respectively). The left ventricular mass index decreased significantly from 133.2 ± 11.7 g/m2 to 114.4 ± 15.7 g/m2 with nicardipine SR and from 137.1 ± 14.8 g/m2 to 99.3 ± 23.0 g/m2 with alacepril (both p < 0.01). The fractional shortening, peak shortening rate, and peak lengthening rate all improved significantly after each treatment. The end-systolic wall stress/left ventricular end-systolic volume index, as an index of left ventricular contractility, was decreased significantly after treatment with nicardipine SR but was not changed after treatment with alacepril. In conclusion, both nicardipine SR and alacepril similarly reduced LVH and improved left ventricular systolic and diastolic function. However, alacepril did not alter left ventricular contractility, whereas nicardi-pine SR decreased left ventricular contractility.  相似文献   
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Homotypic and heterotypic serum isotype-specific antibody responses to rotavirus enterotoxin nonstructural protein (NSP)-4, independent neutralization antigens viral protein (VP)-4 and VP7, and group A rotavirus common antigen VP6 were analyzed by an immunocytochemistry assay in infants who received 1 of several live oral rotavirus vaccines. Significant serum immunoglobulin (Ig) A and IgG antibody responses to homotypic and/or heterotypic NSP4s of genotype [A], [B], or [C] were detected after vaccination. The magnitude of antibody responses to homotypic and heterotypic NSP4s was not significantly different, irrespective of the NSP4 genotype of the administered vaccine strain. In addition, there were no significant differences between IgA antibody responses to homotypic and heterotypic VP7s. In contrast, IgA antibody responses to VP4 were predominantly homotypic. IgA antibody responses to VP7 were lower in magnitude than those to VP4 but were comparable to those to NSP4. Antibody titers to homotypic and/or heterotypic NSP4s were positively correlated with those to VP6 before and after vaccination.  相似文献   
60.
Intrahepatic Portosystemic Venous Shunt: Diagnosis by Color Doppler Imaging   总被引:1,自引:0,他引:1  
Intrahepatic portosystemic venous shunt is a rare clinical entity; only 33 such cases have been reported. It may be congenital, or secondary to portal hypertension. Five patients with this disorder are presented, each of whom was diagnosed by color Doppler imaging, including waveform spectral analysis. One patient with clinical evidence of cirrhosis and portal hypertension had episodes of hepatic encephalopathy and elevated blood levels of ammonia. This patient had a large tubular shunt between the posterior branch of the portal vein and the inferior vena cava. Shunts of this type are considered to be collateral pathways which develop in the hepatic parenchyma as a result of portal hypertension. The other four patients had no evidence of liver disease, and all four evidenced an ancurysmal portohepatic venous shunt within the liver parenchyma. Shunts of this type are considered congenital. The diagnosis of intrahepatic portosystemic venous shunts was established by color Doppler imaging, which demonstrated a direct communication of color flow signals between the portal vein and hepatic vein, in addition to the characterization of the Doppler spectrum at each sampling point from a continuous waveform signal (portal vein) to a turbulent signal (aneurysmal cavity), and finally, to a biphasic waveform signal (hepatic vein). As demonstrated by the five patients, color Doppler imaging is useful in the diagnosis of an intrahepatic portosystemic hepatic venous shunt, and the measurement of shunt ratio may be useful in the follow-up and determining the therapeutic option.  相似文献   
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