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21.
We describe herein the case of a 51-year-old woman in whom metastatic tumor seeding of the percutaneous transhepatic biliary drainage tract occurred following a pancreatoduodenectomy for carcinoma of the distal common bile, duct. An abdominal computed tomography scan done 6 months after the initial operation detected a hepatic lesion located at the site of the previous percutaneous transhepatic biliary drainage tract. Implantation of bile duct carcinoma in the drainage tract was diagnosed, and the recurrent tumor was successfully resected by performing a subsegmentectomy of segment 3 and removal of the adjacent abdominal wall. At present, 5 years and 4 months after the second resection, the patient is in good health without any signs of recurrence. This case report demonstrates that an aggressive surgical approach should be performed for tumor seeding of a transhepatic biliary catheter tract.  相似文献   
22.
Neurons from hypothalamic paraventricular nuclei (PVN) and supraoptic nuclei (SON) from postnatal day 6-8 rats were enzymatically dissociated and separately maintained in monolayer cultures for 14 days. The osmotic pressure of the culture medium, based on Neurobasal medium (Life Technologies), was varied (255, 300 and 330 mOsm/l) by adjustment using mannitol. The survival of oxytocin (OT), vasopressin (VP) and oxytocin-vasopressin (OT/VP) coexpressing neurons were studied under these varied conditions, and the identification of the cell phenotypes in the cultures was carried out by using double-label immunofluorescence. Under control osmolar conditions (300 mOsm/l) equivalent numbers of OT and VP neurons were found in the SON (P = 0.8398) and PVN (P = 0.4721) cultures. The OT neurons' survival did not change in 255 or 330 mOsm media in the SON cultures, but the VP neurons in the SON cultures were significantly increased in 255 mOsm/l medium as compared to control (300 mOsm/l) medium (P = 0.0088). No significant changes were found in VP neuron survival in SON cultures between the 300-330 mOsm/l media (P = 0.2372). Similar data were obtained for the VP neurons in PVN-derived cultures, but the OT neurons in these cultures survived significantly better at 300 mOs/l than at 255 mOsm/l (P<0.0001), but were not significantly different at 330 mOsm/l (P = 0.1208). In general, the VP neurons were more vulnerable than OT neurons to increases of culture medium osmolarity with respect to their survival. The number of OT/VP coexpressing neurons was greater in SON-derived cell cultures as compared to PVN-derived cell cultures, and their numbers were higher in the lower osmolarity media. The effects of adding brain-derived neurotrophic factor (BDNF) to the culture medium on survival were determined. BDNF significantly increased the numbers of all three types of neurons in both PVN and SON cell cultures (P = 0.0001-0.0060). The phenotypically identified cells, cultured in the 300 mOsm/l medium, responded by depolarization or hyperpolarization when transferred to hypertonic or hypotonic perfusion salines, respectively.  相似文献   
23.
Esophageal motor disorders can be primarily focused in the esophagus or secondarily related to a systemic disease. Based on the manometric findings, primary esophageal motor disorders can also be classified into achalasia and spastic disorders, such as diffuse esophageal spasm, nutcracker esophagus, hypertensive lower esophageal sphincter, and nonspecific esophageal motility disorders.  相似文献   
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Although the osteosarcoma is considered to be among the most chemosensitive malignancies and preoperative chemotherapy is commonly applied, an appreciable proportion of cases are in fact quite insensitive. Predictive markers for chemosensitivity are therefore desirable in order to develop effective treatment strategies. Thirty-two cases of conventional osteosarcomas treated at the Cancer Institute Hospital, Tokyo, were analyzed. The sensitivity to preoperative chemotherapy was investigated with reference to loss of heterozygosity (LOH) at the 17p13 ( p 53) and 13q14 ( Rb ) loci and expression of the cell-cycle associated proteins, p53, Rb, p21/Waf-1, mdm-2 and Ki-67, as detected immunohistochemically. LOH was detected by analyzing polymerase chain reaction products at marker microsatellite loci. The efficacy of chemotherapy was evaluated both radiologically and histologically. LOH at p 53 or Rb loci was seen in 54% (13/24) and 58% (14/24) of cases, respectively. Only 15% of osteosarcomas with LOH at the p 53 locus were sensitive to preoperative chemotherapy, as compared to 64% of tumors without such loss ( P <0.05). A similar but much less distinct tendency was observed with LOH at the Rb locus. No relationship was evident between chemosensitivity and immunohistochemical staining patterns for p53, Rb, p21/Waf-1, mdm-2 or Ki-67. The results suggest that p 53 gene deletion, but not the other parameters investigated, may be useful for predicting chemoresistance of osteosarcomas.  相似文献   
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Eicosapentaenoic acid reduces pulmonary edema in endotoxemic rats   总被引:2,自引:0,他引:2  
BACKGROUND: Recently, eicosapentaenoic acid (EPA) was found to have an anti-inflammatory effect attributable to diminished synthesis of arachidonic acid metabolites that initiate acute lung injury. We evaluated the ability of dietary EPA supplementation to prevent endotoxin-induced acute lung injury in rats. MATERIALS ANS METHODS: Rats fed a standard diet were divided randomly into two groups: for 2 weeks one group additionally was fed 1000 mg/kg/day of EPA ethyl ester emulsion (EPA rats), while in the other group the diet was supplemented with vehicle alone (control rats). Fatty acid components of alveolar macrophages (AM) were measured, as well as leukotriene (LT) B(4) and LTB(5) production by AM exposed in vitro to calcium ionophore A23187. Plasma concentrations of thromboxane (Tx) B(2), a stable metabolite of TxA(2), were examined 1 h after inducing lung injury with endotoxin (2 mg/kg iv). At 6 h, wet/dry (W/D) weight ratios were calculated for the lungs to assess pulmonary edema, and neutrophils were counted in pulmonary parenchyma and peripheral blood. RESULTS: Arachidonic acid content and LTB(4) generation in AM were significantly lower in EPA rats than in controls; conversely, EPA content and LTB(5) generation in AM were significantly higher in the EPA group. Neutrophil counts in lung parenchyma and peripheral blood did not differ between groups, but W/D and plasma TxB(2) concentrations were significantly lower in EPA rats. CONCLUSIONS: EPA supplementation depressed arachidonic acid content and LTB(4) generation in AM and plasma TxB(2) in our model, leading to decreased pulmonary edema.  相似文献   
29.
We examined whether a higher plasma lactic acid (LA) concentration resulting from carbohydrate (CHO)-loading affects the cardiovascular responses to exercise through a greater activation of LA-induced metaboreflex. Before and after CHO-loading, LA concentration, mean arterial blood pressure (MAP), heart rate (HR), cardiac output (CO), rating perceived exertion (RPE), and integrated electromyogram (iEMG) of the vastus lateralis were studied during a sustained static knee extension of single legs in 16 volunteers. The CHO-loading comprised an exhaustive bout of one-legged cycling (73+/-3% of maximal oxygen uptake for 130-160 min) and consuming a low-CHO diet for 2-3 days and a high-CHO diet for the next 3 days. In the leg that performed the exercise (the experimental leg), the LA concentration after CHO-loading was significantly increased, but the magnitude of MAP, HR, and CO responses during static exercise was significantly decreased in parallel with a significant reduction of RPE and iEMG. In the control leg, there were no changes in the variables before and after CHO-loading. These results suggest that the increased LA concentration resulting from CHO-loading did not affect the cardiovascular adjustment to the sustained exercise. Other mechanisms related to the reduction of RPE and iEMG seem to be responsible for the attenuated cardiovascular responses observed in the experimental leg after CHO-loading.  相似文献   
30.
IOX4, a hypoxia-inducible factor stabilizer, is classified as a banned substance for horses in both horse racing and equestrian sports. We recently reported the pharmacokinetic profiles of IOX4 in horse plasma and urine and also identified potential monitoring targets for the doping control purpose. In this study, a long-term longitudinal analysis of IOX4 in horse hair after a nasoesophageal administration of IOX4 (500 mg/day for 3 days) to three thoroughbred mares is presented for the first time for controlling the abuse/misuse of IOX4. Six bunches of mane hair were collected at 0 (pre), 1, 2, 3, and 6 month(s) postadministration. Our results showed that the presence of IOX4 was identified in all postadministration horse hair samples, but no metabolite could be detected. The detection window for IOX4 could achieve up to 6-month postadministration (last sampling point) by monitoring IOX4 in hair. In order to evaluate the longitudinal distribution of IOX4 over 6 months, a validated quantification method of IOX4 in hair was developed for the analysis of the postadministration samples. Segmental analysis of 2-cm cut hair across the entire length of postadministration hair showed that IOX4 could be quantified up to the level of 1.84 pg/mg. In addition, it was found that the movement of the incorporated IOX4 band in the hair shaft over 6 months varied among the three horses due to individual variation and a significant diffusion of IOX4 band up to 10 cm width was also observed in the 6-month postadministration hair samples.  相似文献   
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