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41.
Normal epithelial and carcinoma cells of human bladder were investigated for the cytokeratin which is one of the intermediate filaments and comprises cytoskeleton using the immunofluorescence method. Carcinoma cell lines used were JTC-30, JTC-32, HUB-41 and T-24. In normal urothelium, keratin fibers were fine and straight with unchanged diameter and distributed regularly in the cytoplasm. By contrast, keratin fibers in bladder carcinoma cells were kinked and changed in diameter and were distributed irregularly in the cytoplasm. The above findings were most obvious in T-24 which formed undifferentiated carcinoma when transplanted to nude mice, and keratin fibers were dominantly located in the perinuclear area. The changes of keratin fibers appeared to be parallel to the grade of histological anaplasia of the tumor formed by implantation of bladder carcinoma cell line cells to nude mice. These observations suggest that the morphology of cytokeratin is a useful indicator for evaluating the grade of malignancy in transitional cell carcinoma.  相似文献   
42.
Subrenal Capsule Assay (SRCA) as a chemosensitivity test was performed on 14 esophageal squamous cell carcinomas in order to select a more effective form of chemotherapy. Of the 14 assays, 12 were evaluable. Mice were treated with anticancer agents (e.g. Cisplatin, Bleomycin, Methotrexate, Vindesine) on days 1 and 3 after transplantation, and on day 6, the sensitivities were determined. Fresh esophageal cancers yielded an evaluable assay rate of 74%. The implant grew progressively for six days in the remaining group of control mice. Histologically, host cell infiltration at the border of the implant was observed from day 3 after transplantation, and cells had degenerated or had been partially replaced by scar tissue by day 6. The results of chemosensitivity tests differed according to the anticancer agent used or from case to case. Clinically, correspondence between the assay results and clinical results was obtained in 5 out of 7 cases. SRCA is a new promising chemosensitivity test which is clinically useful, and the present results indicated the feasibility of its use in developing an effective chemotherapy for esophageal cancer.  相似文献   
43.
Background. A membrane oxygenator consisting of a microporous polypropylene hollow fiber with a 0.2-μm ultrathin silicone layer (cyclosiloxane) was developed. Animal experimental and preliminary clinical studies evaluated its reliability in bypass procedures.

Methods. Five 24-hour venoarterial bypass periods were conducted on dogs using the oxygenator (group A). In 5 controls, bypass periods were conducted using the same oxygenator without silicone coating (group B). As a preliminary clinical study, 14 patients underwent cardiopulmonary bypass with the silicone-coated oxygenator.

Results. Eight to 16 hours (mean, 12.2 hours) after initiation of bypass, plasma leakage occurred in all group B animals, but none in group A. The O2 and CO2 transfer rates after 24 hours in group A were significantly higher than at termination of bypass in group B (p < 0.005 and p < 0.03, respectively). Scanning electron microscopy of silicone-coated fibers after 24 hours of bypass revealed no damage to the silicone coating of the polypropylene hollow fibers. In the clinical study, the oxygenator showed good gas transfer, acceptable pressure loss, low hemolysis, and good durability.

Conclusions. This oxygenator is more durable and offers greater gas transfer capabilities than the previous generation of oxygenators.  相似文献   

44.
Histamine (HA) is the most important mediator of nasal allergy and nasal hypersensitivity. To investigate HA metabolism, HA content and activities of its synthetic enzyme, histidine decarboxylase (HDC) and degrading enzymes, histamine-N-methyltransferase (HMT) and diamine oxidase (DAO) in nasal mucosa of human and toluene diisocyanate (TDI) sensitized guinea-pigs were measured. In human nasal mucosa and nasal polyps, HA content and HDC activity were 80-200 nmol/g tissue, 20-30 fmol/min/mg protein respectively. Among two degrading enzymes, HMT activity was 20-200 times higher than that of DAO. In the nasal mucosa of guinea-pigs, HA content was significantly increased by TDI sensitization, and was decreased immediately after TDI provocation. In 24 hours after provocation, HA content recovered to 80% of pre-provocation level. HDC activity increased by TDI sensitization significantly. Though HMT activity increased slightly by TDI sensitization and provocation, DAO activity was unchanged. The data suggest that, increase in turnover rate of HA is present in allergic nasal mucosa.  相似文献   
45.
The cerebellomedullary fissure, the only entrance or exit to the fourth ventricle, is surrounded rostrally by the cerebellar tonsils and the biventral lobules and caudally by the medulla oblongata, the tela choroidea, and the lateral recesses. This fissure is an important route in operations on the fourth ventricle. We studied the microsurgical and magnetic resonance imaging (MRI) anatomy of the fissure by using autopsied normal cerebellum. MRI revealed that the fissure is visible as a slit and is indicated by the enhanced choroid plexus and the flocculus. Oriented by the anatomical information thus obtained, we have surgically treated nine patients with a tumor either in or around the fourth ventricle. Preoperative MRI clearly demonstrated the tumors in relation to the cerebellomedullary fissure. It revealed the precise anatomical location and extension of the tumor, not only its inferior extension but also its lateral one. The MRI findings and microsurgical anatomy of the cerebellomedullary fissure were quite useful for the removal of the tumors in the fourth ventricle.  相似文献   
46.
The purpose of this study was to analyze the management of individual patients with unruptured intracranial aneurysms (UN-ANs) using a decision-analytic approach. Transition probabilities among Glasgow Outcome Scale (GOS) categories were estimated from the published literature and data from patients who had been treated at Kitasato University Hospital. Utilities were obtained from 140 health providers based principally on the GOS. Baseline analysis for a healthy 40-year-old man with an anterior UN-AN less than 10 mm in diameter showed that the quality-adjusted life expectancies for preventive operation and follow-up were 15.34 and 14.66 years, respectively. For a follow-up strategy to be preferred, the annual rupture rate had to be as low as 0.9%. These results were sustained through extensive sensitivity analysis. The results support preventive operation for UN-ANs, and identify problems that can be clarified with a well-designed stratified clinical trial.  相似文献   
47.
Twenty-one patients with germ cell tumors (17 germinomas and 4 teratomas) involving the hypothalamic-neurohypophysial (HN) region were reviewed retrospectively. Eleven patients were males and 10 females, and their ages ranged from 7 to 45 years (average 18.5 years). Diabetes insipidus was the initial and the most prominent symptom in most germinomas; in teratomas the most prominent symptom was visual disturbance. Fifteen patients with germinomas were treated by radiotherapy, and 4 with teratomas were treated by surgical resection alone. Two recent germinoma patients with extensive CSF dissemination were treated with systemic chemotherapy consisting of anticancer platinum drugs and etoposide, which resulted in a complete disappearance of the tumors. Patients with germinoma treated after the introduction of CT scanning had a greatly improved mortality rate, and their actual survival rate was 87.5% over 10 years. On the basis of this review, the authors consider that diagnosis at an early stage of the disease and chemotherapy, which can be an effective therapeuric alternative to radiation therapy, may improve not only the mortality rate but also the quality of life of patients with HN germ cell tumors.  相似文献   
48.
Clonal plants propagated from a single plant of a commercial variety of ANGELICA ACUTILOBA (Umbelliferae) through somatic embryoids induced in cell suspension cultures proved to be significantly more uniform with respect to the contents of medicinally important chemical constituents (ligustilide and choline) of the root when compared with seed-propagated plants.  相似文献   
49.
Summary The renal and hormonal effects of the 1-adrenoceptor blocker bunazosin were examined in 6 patients with essential hypertension. Oral bunazosin for 4 to 12 weeks significantly decreased mean blood pressure by 10%, increased effective renal blood flow and creatinine clearance by 34% and 37%, respectively, the plasma norepinephrine concentration was elevated by 60%, and the plasma atrial natriuretic peptide level was lowered by 22%. The plasma renin activity and aldosterone concentration were unchanged. Thus, a moderate reduction in blood pressure was produced by bunazosin treatment while maintaining renal perfusion.  相似文献   
50.
Recurrent chromosomal gain at 1q is one of the most common features of human hepatocellular carcinoma (HCC), but how the gain at 1q contributes to hepatocarcinogenesis is still unclear. To identify the target genes, precise determination of the shortest region of overlap (SRO) and of breakpoints is necessary. Similarly, the role of loss at 1p, which is also a major cytogenetic aberration in HCC, needs to be determined. Fifty HCCs were examined with the aid of 59 microsatellite markers distributed throughout both arms of chromosome 1. To detect allelic gain effectively, the cutoff value of the allelic imbalance index was set at 0.70. Alleles showing imbalance were subjected to multiplex PCR, using a retained allele as an internal control, to determine whether the imbalance was the result of chromosomal gain or loss. The SRO of the gains was defined as D1S2878-D1S2619 (1q23.-q25.3, 16.9 Mb), which involved 36 cases (72%). Gains in the number of copies of certain oncogenes within this region seemed to be critical for the pathogenesis of HCC. In contrast, the centromeric breakpoints of these gains varied, but they tended to occur mainly in the pericentromeric region (26 of 50 cases, 52%). Rearrangement of specific genes associated with the gains is unlikely. On the other hand, the SRO of deletion was defined as D1S2893-D1S450 (1p36.32-p36.22, 5.1 Mb). Four known putative tumor-suppressor genes (TP73, RIZ1, NBL1/DAN, and CDKN2C) were outside the SRO, suggesting the presence of other candidate genes with critical roles in hepatocarcinogenesis.  相似文献   
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