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11.
A 43-year-old male with a history of autosomal dominant polycystic kidney disease (ADPKD) was admitted to our center with severe abdominal pain and was diagnosed with acute pancreatitis. CT showed multiple cysts in the liver and both kidneys along with ADPKD and a cystic mass, 4 cm in diameter, in the pancreatic head. The main pancreatic duct was dilated to 1 cm in diameter. The patient was diagnosed with acute pancreatitis due to intraductal papillary mucinous tumor (IPMT), and pancreatoduodenectomy was performed. Histologic examination revealed a multiloculated cystic tumor filled with mucin in the head of the pancreas. Microscopically, the tumor was diagnosed as adenocarcinoma and was found to have invaded the main pancreatic duct. Although, in addition to our case, only seven cases with association between ADPKD and malignant neoplasms have been reported, five of these cases had neoplasms arising from the pancreas. Therefore, we suggest that some genetic interactions may exist between ADPKD and pancreatic carcinogenesis.  相似文献   
12.
Effects of cueing on visuospatial processing in unilateral spatial neglect   总被引:2,自引:0,他引:2  
Patients with typical left unilateral spatial neglect bisected lines after cueing to the left end-point, the fixation point being monitored with an eye camera. They persisted with the point of initial fixation made after cueing and placed the mark there without searching leftwards again. The rightward shift of fixation to the initial point of fixation thus determined the location of the subjective midpoint. We consider that rightward attentional bias increased the amplitude of this shift that was planned on the basis of the perception of the whole line while cueing. This hypothesis may explain smaller but obvious rightward bisection errors found in the cueing condition.  相似文献   
13.
 The aims of this study were (1) to evaluate subjective symptoms in the hand-arm system of all traffic police motorcyclists of a city located in the central part of Japan and (2) to assess their hand-arm vibration exposure associated with traffic police motorcycle riding. The study population consisted of 119 motorcycling traffic policemen and 49 male controls. By means of a questionnaire, information on the occupational history and the presence of subjective symptoms in the hand-arm system of all subjects was obtained. Vibration was measured on the handlebars of the representative motorcycles and on the hands of the riders. The 4- and 8-h energy-equivalent frequency-weighted acceleration as well as the lifetime vibration dose were calculated for all police motorcyclists. The prevalence of finger blanching in the traffic police motorcyclists was 4.2%, but none of the controls had this symptom. The rates of finger numbness (19.3%), finger stiffness (16.0%), shoulder pain (13.4%), and shoulder stiffness (45.4%) were significantly higher among police motorcyclists as compared with controls. The root-mean-square (rms) frequency-weighted acceleration on the handlebars of police motorcycles was in the range of 2.2–4.9 m/s2 rms. The computed 4- and 8-h energy-equivalent frequency-weighted acceleration values were 2.8– 4.5 and 2.0 –3.2 m/s2 rms, respectively. A pattern of increasing percentage prevalence with increasing cumulative vibration dose was noticed. The subjects with a lifetime vibration dose of more than 20.1 m2 h 3 s-4 (ln scale) showed significantly higher prevalence rates for symptoms in the fingers and shoulders as compared with the control group. As occupational vibration exposure of traffic police motorcyclists might be considered a risk factor for the development of symptoms in the hand-arm system of the riders, its evaluation and control is needed for prevention methodology evolution. Received: 15 April 1996/Accepted: 8 November 1996  相似文献   
14.

Background  

Maharishi Amrit Kalash (MAK) 5, one of the Ayurvedic food supplements, belongs to a group of substances known as Rasayana. MAK5 and other Rasayanas are believed to enhance the body's resistance to infections and disease, and enhance longevity. In this study, we determined the effects of administration of MAK5, one of the Ayurvedic food supplements on immune functions in young and old mice.  相似文献   
15.
We investigated the fine structure and mineral components of 29 stonelike masses obtained from the mesenteries of four adult cadavers, using optical microscopy, backscattered electron imaging, scanning electron microscopy, energy-dispersive X-ray microanalysis, and X-ray diffraction. Although the overall appearance of the stonelike masses measuring about 5–20mm in diameter and 0.06–3.1g in dry weight was roughly grouped into smooth bulb- and uneven bulk-shaped types, all the calcified masses basically consisted of core and mantle regions. The smooth bulb-shaped masses had a broad mantle with many concentric rings, whereas the uneven bulk-shaped masses contained a large core. In their core regions, spherulitic and short bundle-shaped deposits composed of needle-shaped apatite crystals were mainly found among loose collagen fibers. Their mantle regions, on the other hand, showed the concentric structures of dense collagen fibers in the intra- and/or extrafibrous calcification with fine sandy grain-shaped deposits. The mineral elements were mainly Ca and P, and the major crystals were hydroxyapatite. Hexahedral whitlockite containing Mg was a minor component. The fiber-rich mantle regions showed lower calcification and lesser crystallization than the fiber-poor core region. When necrotic or some tumor adipose tissues and necrotic lymphoid tissues that might have been caused by some digestive diseases are recognized as foreign matter, their tissues occasionally will be calcified and grow into stonelike masses. These stonelike masses tend to occur more often in women than in men.  相似文献   
16.
PROBLEM: Tumor necrosis factor-alpha (TNF-alpha) is present in human placental and uterine cells at the early and late stages of gestation and promotes the regulation of trophoblast growth and invasion. We evaluated whether TNF-alpha levels in the placenta and blood of pre-eclamptic women differed from those with normal pregnancies. METHOD OF STUDY: The subjects were 39 pregnant women carrying single fetuses (21 normal-pregnant and 18 pre-eclamptic patients). Their average gestational age at entry was 38-39 weeks. Peripheral blood was collected before the onset of labor and separated serum was stored at -20 degrees C. A tissue segment of the placenta was cut and frozen in liquid nitrogen immediately after delivery at -80 degrees C. The frozen placental tissue was added to phosphate-buffered saline. The tissue was fully homogenized and centrifuged. Separated supernatant was stored at -80 degrees C. TNF-alpha levels in separated serum and TNF-alpha and total protein (TP) levels in separated supernatant were measured. The presence of TNF-alpha in the placenta was evaluated by immunohistochemistry in five pre-eclamptic and five normal-pregnant patients. RESULTS: Serum TNF-alpha levels were higher in pre-eclampsia than in normal pregnancies. However, TNF-alpha/TP levels in the placenta did not differ significantly between the two groups. As for TNF-alpha immunostaining of trophoblastic cells in the placenta, it was weak in three and moderate in two of the normal pregnancies, while it was absent in two, weak in one, and moderate in two in the pre-eclampsia group. CONCLUSIONS: We demonstrated no significant increase in TNF-alpha/TP levels in the placenta in pre-eclampsia despite a significant increase in serum TNF-alpha levels. There was no strong immunostaining for TNF-alpha detected by immunohistochemistry in the pre-eclampsia group. These findings suggest that TNF-alpha in the placenta is not a key cytokine to interfere with normal trophoblast invasion into the myometrium in pre-eclampsia, and that sources other than the placenta may contribute to the elevated levels of TNF-alpha found in the circulation of pre-eclamptic patients.  相似文献   
17.
Carbohydrate expression of cancer cells is closely related to the metastatic nature of colorectal cancer. In the present study we investigated the relevance of carbohydrate expression profiles of colorectal cancer cells in the primary lesion to metastatic distribution patterns as well as prognosis in 134 cases. Carbohydrate expression was estimated by histochemistry with 17 kinds of lectins and 3 kinds of Lewis-related monoclonal antibodies (MAbs), and correlations between the staining and clinicopathological parameters were examined. The results showed that lymphatic invasion, lymph node metastasis, and peritoneal metastasis correlated with staining with lectins that bind galactose/N-acetylgalactosamine residues (Gal/GalNAc) such as Maclura pomifera (MPA), Arachis hypogaea (PNA), Helix pomatia (HPA), and Vicia villosa (VVA). In contrast, hepatic metastasis correlated with staining with Anguilla anguilla lectin (AAA), anti-LewisX (LEX-2), anti-sialyl Lewisa (NS19-9), and anti-sialyl-dimeric LewisX (FH-6) MAbs, all of which bind preferentially to fucosylated carbohydrate chains. The five-year survival rate of patients was related to the staining of cancers with MPA, HPA, FH-6 or NS19-9, and MPA- and FH-6 staining were independent prognostic factors. We conclude that carbohydrate expression profiles of cancer cells are relevant to the route of tumor cell dissemination, metastatic pattern as well as prognosis of colorectal cancer.  相似文献   
18.
High expression of thymidylate synthase (TS) is allegedly associated with the chemoresistance to 5-fluorouracil (5-FU) in colorectal cancers. However, low TS expression does not necessarily imply chemosensitivity. Inactivation of p16(INK4a) correlates with poor prognosis in various cancers. We immunohistochemically evaluated the relationship between the expression of TS, p16(INK4a), CDK4 and cyclin D1 and the effect of 5-FU-based chemotherapy in colorectal cancers. After antigen retrieval, immunoperoxidase staining was performed on the paraffin-embedded, biopsy and surgical specimens of 37 advanced colorectal cancers preoperatively treated with peroral administration of 5-FU derivatives. As a control group, 31 colorectal cancers without preoperative treatment were analyzed. High TS expression was found in 23 (74%) of 31 tumors resected from histological non-responders and in 19 (61%) of 31 controls but in none of six responders. High p16(INK4a) expression was seen in 83% of the responders, 52% of the non-responders and 32% of the controls. The TS-low/p16(INK4a)-high phenotype was noted in 83% of the responders, but only in 3% of the non-responders (P = 0.0001). Induction of p16(INK4a) expression after chemotherapy was predominantly seen in the responders. Neither CDK4 nor cyclin D1 expression was related to the chemotherapeutic effects. In conclusion, the combination of low expression of TS and induction of p16(INK4a) after chemotherapy can be important indicators of the sensitivity to 5-FU-based chemotherapy in colorectal cancers.  相似文献   
19.
The aim of this study was to investigate cell kinetics and ultrastructural changes during carcinogenesis using a hamster 9,10-dimethyl-1,2-benzanthracene (DMBA)-induced tongue cancer model. Five squamous cell carcinomas, five dysplastic epithelia, seven hyperplastic epithelia, and four normal epithelia were obtained from 21 hamster tongues by applying 1.0% acetone solution of DMBA on the left lingual mucosa after scratching with a root canal broach. Ultrastructural examination revealed that the number of microvilli increased, whereas that of desmosomes decreased during carcinogenesis. Cell proliferation was analyzed by means of 5-bromodeoxyuridine (BrdU) immunohistochemistry and in situ hybridization (ISH) for histone H3 mRNA. The BrdU and histone H3 mRNA labeling indices (LIs) were lowest for normal epithelium, higher for hyperplastic and dysplastic epithelia, and highest for squamous cell carcinoma. Cytoplasmic histone H3 mRNA and nuclear BrdU were localized in virtually identical areas of serial sections. The correlation coefficient for the relationship between these two LIs was 0.97 (P 0.001). These results suggest that the assessment of cell proliferation using H3 mRNA ISH will be a useful technique for investigating biological behavior during carcinogenesis.  相似文献   
20.
The interaction between poly(A) · poly(U) duplex and dyes (proflavine (PF) and 9-aminoacridine (9-AA)) was studied by means of the heat of mixing. From the results, thermodynamic quantities of poly(A) · poly(U) duplex-dye systems for the intercalation process were estimated. The free energy change for the poly(A) · poly(U) duplex-(PF) system is smaller than that for the poly(A) · poly(U) duplex-(9-AA) system, indicating that PF intercalated into poly(A) · poly(U) duplex is more stable than the intercalated 9-AA. This conclusion is based on the absolute value of the heat of interaction between PF and poly(A) · poly(U) duplex being larger than that between 9-AA and the poly(A) · poly(U) duplex.  相似文献   
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