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71.
Pseudocyst of the pancreas is sometimes difficult to distinguish from mucinous cystic neoplasm of the pancreas. A 37-year-old asymptomatic Japanese man was diagnosed with hypertension. He had a 20-years history of habitual drinking of alcohol, but no history of pancreatitis or abdominal trauma. During examinations to ascertain the cause of hypertension, ultrasonography and computed tomography incidentally demonstrated a huge cyst in the head of the pancreas. Laboratory data were within normal limits, including serum levels of amylase, carcinoembryonic antigen, and carbohydrate antigen 19-9. Imaging studies showed a huge unilocular cyst, measuring 7 cm, in the head-to-body of the pancreas, and two small unilocular cysts, measuring 1.4 and 1.5 cm, in the tail and head of the pancreas, respectively. A mural nodule was suspected in the largest cyst. Endoscopic retrograde cholangiopancreatography demonstrated communication of the main pancreatic duct with the two small cysts in the head and tail of the pancreas but not with the huge cyst. There were no ductal changes suggesting chronic pancreatitis. Laparotomy was performed under the tentative diagnosis of potentially malignant mucinous cystic neoplasms of the pancreas. However, inflammatory adhesion was dense around the pancreas and the mural nodule suspected preoperatively was found to be sludge aggregates in a pseudocyst. The diagnosis of an intraoperative frozen section of the cyst wall was pseudocyst of the pancreas. Cystojejunostomy was performed. We report this case because the pre-operative diagnosis was mucinous cystic neoplasm of the pancreas, but the diagnosis changed with careful intraoperative examinations, to pseudocyst of the pancreas. We discuss the differential diagnosis of the two conditions. (Received Oct. 1, 1997; accepted Jan. 23, 1998)  相似文献   
72.
Breast cancer is the most common cause of cancer death in women in this country. Until recently, the traditional treatment has been radical surgery with or without radiation therapy for patients with primary breast cancer, and palliative endocrine therapy followed by chemotherapy for patients with advanced disease. These treatments have met with limited effectiveness in terms of eradicating the disease. Studies in the past decade have given cause for optimism for breast cancer patients. Adjuvant systemic therapy after local treatment appears promising for certain subsets of patients with primary breast cancer. The development of estrogen receptor assays has markedly changed our approach to the disease and improved patient care. Estrogen receptor is an important prognostic factor and is useful in planning appropriate therapy for patients with primary breast cancer as well as those with advanced disease. Further research is urgently needed to improve the dismal survival of certain women with this common malignancy.  相似文献   
73.
Several studies have shown the benefit of withdrawal therapy when medication overuse headache (MOH) is suspected. Our aim was to compare the effect of withdrawal therapy in patients followed by a neurologist (group A, n  = 42) and a primary care physician (PCP) (group B, n  = 38). Patients were randomized to A or B, and follow-up was at 3, 6 and 12 months. Calculated mean headache (MH at 6 months + MH at 12 months)/2 (primary end-point) was similar; A 1.04 (0.87, 1.21) and B 1.02 (0.82, 1.21) ( P  = 0.87). The number of patients with 50% improvement of headache days was also similar; 14/42 in group A vs. 12/34 in B ( P  = 0.86) at 3 months, 15/42 vs. 11/33 ( P  = 0.83) at 6 months and 15/42 vs. 14/38 ( P  = 0.92) at 12 months. Days without headache during the last 9 months of follow-up were 123 (96, 150) in group A and 137 (112, 161) in B ( P  = 0.62). After 3 months one-third were classified as MOH. Patients with MOH improved similarly in group A and B, and so did patients without MOH. Within 1 year 7/42 in A and 9/38 in B had recurrent medication overuse ( P  = 0.43). In summary, there were no significant differences in follow-up results between the two groups.  相似文献   
74.
Visual agnosia has been well studied by anatomical, neuropsychological and neuroimaging studies. However, functional changes in the brain have been rarely assessed by electrophysiological methods. We carried out electrophysiological examinations on a 23-year-old man with associative visual agnosia, prosopagnosia and cerebral achromatopsia to evaluate the higher brain dysfunctions of visual recognition. Electrophysiological methods consisted of achromatic, chromatic and category-specific visual evoked potentials (CS-VEPs), and event-related potentials (ERPs) with color and motion discrimination tasks. Brain magnetic resonance imaging revealed large white matter lesions in the bilateral temporo-occipital lobes involving the lingual and fusiform gyri (V4) and inferior longitudinal fasciculi due to multiple sclerosis. Examinations including CS-VEPs demonstrated dysfunctions of face and object perception while sparing semantic word perception after primary visual cortex (V1) in the ventral pathway. ERPs showed abnormal color perception in the ventral pathway with normal motion perception in the dorsal pathway. These electrophysiological findings were consistent with lesions in the ventral pathway that were detected by clinical and neuroimaging findings. Therefore, CS-VEPs and ERPs with color and motion discrimination tasks are useful methods for assessing the functional changes of visual recognition such as visual agnosia.  相似文献   
75.
76.
PURPOSE: Dropped head syndrome is characterized by a gradual forward sagging of the head due to the isolated weakness of the neck extensor muscles. The syndrome has a relatively benign clinical course. To date, there have been no reports of dropped head syndrome in epileptic patients. METHODS: Nine patients with intractable epilepsy (mean age, 33.6+/-9.91 years), each presenting with apparent dropped head, were evaluated. The duration of the drooping head symptom varied from 3 to 15 years (mean, 7.4+/-4.06 years), with a slowly progressing weakness in most of the patients. In all of the patients, extensive clinical, laboratory, electrophysiological, histopathological, and neuroimaging examinations were performed. RESULTS: The weakness in all of the subjects was strictly limited to the cervical paraspinal muscles. Laboratory studies produced normal results from all subjects. EMG and muscle biopsy were normal or revealed subtle nonspecific myopathic changes without inflammation in the cervical paraspinal muscles. Polymyographic investigation revealed that none of the patients had convincing dystonic spasms of the anterior neck muscles. No atrophy or fatty changes of the neck extensor muscles were observed on CT or MRI. In most of the patients (7/9), altered L-carnitine concentrations were observed (four patients displayed a marked decrease in plasma carnitine concentrations, and three other patients showed abnormalities in urinary excretion of carnitine). CONCLUSIONS: These findings seem to suggest that a secondary carnitine deficiency, induced by antiepileptic drugs (principally valproic acid), represents a plausible pathogenetic mechanism for the development of dropped head in some epileptic patients.  相似文献   
77.
78.
BACKGROUND: Selenium (Se), an essential trace element, is known to be a cofactor of antioxidative selenoenzymes such as glutathione peroxidase and thioredoxin reductase. METHODS: We assessed the pathophysiological significance of selenium (Se) by comparing the concentrations of serum Se and C-reactive protein (CRP) in healthy subjects (141; M=71, F=70) vs. patients with various pathological conditions. RESULTS: In normal males in their 40s, peak serum Se concentrations were observed (2.03+/-0.30 microg/g of serum protein, 128%, P<0.001) vs. males in their 20s (1.59+/-0.20), whereas a peak was observed in females in their 30s (1.87+/-0.31, 119%, P<0.025) vs. those in their 20s (1.57+/-0.22). The serum Se concentrations in the high CRP value group (n=40, 1.07+/-0.29 microg/g, 64.1%), the rheumatoid arthritis (RA) test positive group (n=24, 1.37+/-0.29, 82.0%), the lung cancer group (n=16, 1.38+/-0.30, 82.6%), and the adult T-cell leukemia (ATL) group (n=22, 1.26+/-0.35, 75.4%) were significantly lower (P<0.001) than those in the healthy subjects (1.67+/-0.29 microg/g). This finding was confirmed by inducing acute phase response (APR) in rats by injection of lipopolysaccharide (LPS), which produced a significant decrease of Se in plasma and liver (69.5% and 81.6% vs. untreated rats, P<0.05). In contrast, the Se content in muscle, kidney, lung, spleen, heart, and thymus showed increases of <10%. Se mobilized from liver after LPS-challenge appeared to be translocated to muscle, and Se concentrations recovered by 80 h after APR to the control concentrations in parallel with the subsidence of APR. CONCLUSIONS: The reduction of Se in the liver and plasma during APR may be associated with the increased CRP synthesis in the liver.  相似文献   
79.
Plasma high-density lipoprotein is commonly estimated by measuring the cholesterol remaining in plasma supernatant solutions after other lipoproteins, which contain apolipoprotein B, are precipitated with heparin and Mn2+. The method (method I) now in use by the Lipid Research Clinics, in which Mn2+ is at 46 mmol/liter final concentration, is reasonably accurate, but precipitation and sedimentation of lipoproteins other than high-density lipoproteins is often incomplete. We evaluated two modifications of method I. In method II, the Mn2+ concentration was doubled; the second modification (method III) included the increased Mn2+ concentration in a combined heparin Mn2+ reagent, decreased sample volume (2 ml), and a shorter incubation time (10 min at room temperature). The percentages of samples with turbid supernates (i.e., incomplete sedimentation) by methods I, II, and III were 9, 3, and 2%, respectively. Among non-turbid supernates, the percentages of samples containing measurable apolipoprotein B (incomplete precipitation) were 79, 19, and 16%, respectively. We conclude that method III is the most convenient and accurate of the three procedures.  相似文献   
80.
The histologic features of thymuses from three patients who underwent thymectomy for acute lymphoblastic leukemia or lymphoblastic lymphoma in complete clinical remission are described. The thymuses from all three patients were fibrotic with a variability in the appearance of the lobules. Some of the lobules consisted predominantly of epithelial cells with small numbers of mature appearing lymphocytes, while other lobules were expanded and composed predominantly of cells having morphological features of immature lymphoid cells consistent with residual or recurrent disease.  相似文献   
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