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51.
Abstract Background: Yolk sac tumors (YST) exhibit several different histological subtypes and the mechanisms of cellular differentiation and prognosis of each subtype remain unknown.
Results: We report two infants with sacrococcygeal YST; one represented a typical histological subtype and the other showed a hepatoid subtype with uniform histology. The isoform of alpha-fetoprotein (AFP) in the patient with the hepatoid pattern was examined by lectin-affinity Immunoelectrophoresis and represented as a YST. but not hepatocellular, subtype. The patient with typical YST responded well to VAB-6 combination chemotherapy. However, this regimen was only partially effective to the patient with the pure hepatoid histological subtype, and an etoposide with ifosfamide and cisplatin (VIP) regimen as a salvage chemotherapy combined with complete tumor resection was useful to achieve complete remission (CR). Both of the patients have been in CR for more than four years.  相似文献   
52.
Kallikrein content and cellular localization in the prenatal, newborn and adult rat brains were determined by the enzyme-linked immunosorbent assay and immunohistochemistry. The content was the highest in the prenatal rats and highly predominant in the neuronal nuclei during the prenatal to newborn periods, whereas the immunoreactive kallikrein was mainly located around neuronal cell bodies and their processes in the adult rats. The preferential nuclear localization in the prenatal rat brains was further confirmed by the immunoblotting technique after the SDS-polyacrylamide gel electrophoresis of the lysate of the nuclei fractionated from the prenatal rat brains. The meaning(s) of this kallikrein localization in the neuronal nuclei at the prenatal and newborn stages is unknown. However, we would like to conclude that this enzyme plays an important role in the morphogenesis of brain by acting on the substance(s) in the neuronal nuclei at the developing stage.  相似文献   
53.
We determined whether milrinone, a phosphodiesterase III inhibitor, attenuates serotonin-induced (5-hydroxytryptamine [5HT]) pulmonary hypertension (PH) and bronchoconstriction. Dogs were anesthetized with pentobarbital (30 mg/kg + 2 mg. kg(-1). h(-1)). Bronchoconstriction and PH were elicited by 5HT (10 microg/kg + 1.0 mg. kg(-1). h(-1)). Pulmonary vascular resistance was used to assess PH. Bronchoconstriction was also assessed by changes in bronchial cross-sectional area obtained from our bronchoscopic method. At 30 min after 5HT infusion started, seven dogs were given milrinone: 0 (saline), 5, 50, 500, and 5000 microg/kg at 10-min intervals. The other 12 dogs were given milrinone 5000 microg/kg 30 min after 5HT infusion, and 5 min later were given propranolol 0.2 mg/kg (n = 6) or saline (n = 6) IV. The 5HT significantly increased percentage of pulmonary vascular resistance to 208% +/- 27% and decreased percentage of bronchial cross-sectional area to 52% +/- 5% of the basal. Milrinone significantly attenuated both PH and bronchoconstriction in a dose-dependent manner. However, -log 50% effective concentration (mean ED(50) in microg/kg) of milrinone for bronchoconstriction: 4.32 +/- 0.13 (47.6) was significantly smaller than that for PH: 3.84 +/- 0.29 (144.9) (P < 0.01). In addition, the spasmolytic effects of milrinone (5000 microg/kg) were not antagonized by propranolol, although this dose significantly increased plasma catecholamines. In conclusion, milrinone attenuates 5HT-induced PH and bronchoconstriction; however, this drug may be more sensitive to phosphodiesterase III in the airway smooth muscle than in pulmonary vascular smooth muscle. In addition, the relaxant effects could not be caused by beta-adrenoceptor activation because beta-blocker did not antagonize. IMPLICATIONS: We studied the effects of milrinone on serotonin-induced pulmonary hypertension and bronchoconstriction in dogs. Milrinone produces pulmonary vasodilation and bronchodilation, whose effects may not be caused by beta-adrenoceptor activation. In addition, this drug may be more sensitive to phosphodiesterase III in the airway smooth muscle than that in pulmonary vascular smooth muscle.  相似文献   
54.
The coexistence of cholelithiasis and abdominal aortic aneurysm is not uncommon. However, cholecystectomy at the time of abdominal aortic reconstruction has generally been delayed because of the potential contamination of the graft. The case described here had concomitant cholelithiasis and abdominal aortic aneurysm, both of which were required to be treated, and was successfully treated with a combination of retroperitoneal abdominal aortic reconstruction and gasless laparoscopic cholecystectomy.  相似文献   
55.
Between 1989 and 2002, 28 patients with locally advanced cervical adenocarcinoma (bulky IB-IIIB) were recruited for a pilot study aimed at evaluation of the effectiveness of neoadjuvant chemotherapy with cisplatin, aclacinomycin-A, and mitomycin-C (PAM), followed by radical surgery. This regimen was administrated intra-arterially or intravenously. In addition to patients treated with PAM, we retrospectively analyzed the prognoses of 26 patients in stage I and II, who had been treated between 1975 and 1981 with radical surgery with/without radiation therapy. Twenty-eight patients received PAM therapy as neoadjuvant chemotherapy, and 75.0% of the 16 intra-arterially infused patients showed a response, as did 66.7% of the 12 intravenously infused patients. There was a significant difference in the 5-year prognosis of stage II (PAM group, 72.9%; without-PAM group, 36.4%). The results suggest that, as the free space in the parametrium is widened by neoadjuvant chemotherapy with PAM, it is possible that the tumor could be completely resected by radical hysterectomy. Thus, neoadjuvant chemotherapy with PAM is expected to improve the survival rate of patients with advanced cervical adenocarcinoma by the preliminary study. However, the survival rates of stage II with lymph node metastasis in the without-PAM group seem low, and we must also consider that the various technologies to evaluate and treat the cervical adenocarcinomas, e.g. computed tomography, magnetic resonance imaging, and surgical equipments, had improved during 1989-2002 than was the scenario during 1975-1981, and these improvements contributed to better prognosis. A prospective-randomized study is needed to assess the value of this approach compared with standard management.  相似文献   
56.
Presynaptic dopamine metabolism was studied in a group of patients with schizophrenia and in an age- and gender-matched normal control group using 6-[(18)F]fluoro-L-DOPA ((18)F-DOPA) and positron emission tomography (PET). Nineteen patients, nine drug-free, 10 on neuroleptics, and 13 normal control subjects underwent PET scans using (18)F-DOPA. The neuroleptic-treated patients were taking typical neuroleptics (N=4) or the atypical neuroleptic, clozapine (N=6). The ratio of specific/non-specific activity was calculated for eight cortical and subcortical regions of interest. Medication-free patients had a significant reduction in (18)F-DOPA uptake in the ventral striatum (P=0.04) and significantly increased uptake in the posterior cingulate (P=0.02) compared with normal control subjects. The 18F-DOPA PET technique proved to be useful and sensitive in detecting changes in dopamine metabolism in patients with schizophrenia in vivo. The results of this study provide evidence of an aberrant dopamine system in schizophrenia.  相似文献   
57.
The localization of mRNA for SHIP2, SH2 domain containing inositol 5-phosphatase SHIP isozyme, was examined by in situ hybridization histochemistry in the brain of developing and mature rats. SHIP2 mRNA was first detected in the ventricular germinal zone at embryonic stages. As the postnatal development proceeded, the expression signal was evident in cell of the white matters, presumptive oligodendrocytes, and no significant expression was seen in neurons throughout the development.  相似文献   
58.
59.
Drainage therapy for malignant biliary obstruction (MBO) includes trans-papillary endoscopic retrograde biliary drainage (ERBD), percutaneous transhepatic biliary drainage (PTBD), and trans-gastrointestinal endoscopic ultrasound-guided biliary drainage (EUS-BD). With the development of chemotherapy, many MBO cases end up needing endoscopic reintervention (E-RI) for recurrent biliary obstruction. To achieve a successful E-RI, it is necessary to understand the various findings regarding E-RI in MBO cases reported to date. Therefore, in this review, we focus on E-RI for ERBD of distal MBO, ERBD of hilar MBO, and EUS-BD. To plan an appropriate E-RI strategy for biliary stent occlusion for MBO, the following must be considered on a case-by-case basis: the urgency of the drainage, the cause of the occlusion, the original route of drainage (PTBD/ERBD/EUS-BD), the initial stent used (plastic stent or self-expandable metallic stent), and in the case of self-expandable metallic stents, the type used (fully covered or uncovered). Regardless of the original method of stent placement, if the inflammation caused by obstructive cholangitis is severe and/or the patient is in shock, PTBD should be considered as the first choice. Finally, it is important to keep in mind that in many cases, performing E-RI will be difficult.  相似文献   
60.
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