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41.
We used the qualitative Hanssen technique in albino rats to seek morphologic demonstration of tubular obstruction in two types of acute renal failure: one induced by folic acid and another by methemoglobin. Immediately after the intravenous injection of folic acid, 250 mg/kg body weight, the animals became almost anuric. Two to three hours after the injection, sodium ferrocyanide remained within the proximal convoluted tubules. After the intravenous injection of methemoglobin, 0.5 to 1.0 g/kg body weight, the animals became oliguric but not anuric. Sodium ferrocyanide injected with methemoglobin was seen mainly in distal tubules and collecting ducts 2 to 3 hours after the injection. The degree of tubular dilatation was more marked in the former model than in the latter, in agreement with the degree of oliguria. These morphologic findings were taken to indicate that the above two types of acute renal failure were caused by tubular obstruction rather than by intrarenal vasoconstriction and subsequent cessation of glomerular filtration. (Am J Pathol 87:323-330, 1977). 相似文献
42.
Yang M Moriya T Oguma M De La Cruz C Endoh M Ishida T Hirakawa H Orita Y Ohuchi N Sasano H 《Pathology international》2003,53(7):422-428
Microinvasive ductal carcinoma of the breast, namely ductal carcinoma in situ with microinvasion (T1mic) as defined by the American Joint Committee on Cancer (AJCC) Staging Manual, is a rare disease, although it is increasing because of widespread use of mammography. The aim of the present study was to describe the clinicopathological and immunohistochemical features of this entity. Twenty-eight patients who were diagnosed as T1mic from January 1997 to August 2002 were studied by using 3-5 mm-thick serial sections with hematoxylin-eosin staining. Immunohistochemical staining for the estrogen receptor (ER), progesterone receptor (PR), p53, Ki-67, and HER-2 were performed. All 28 patients were female, with a mean age of 48.8 years. Twenty-six patients (93%) revealed mammographic abnormalities on routine examination. All foci of the invasions were measured using an ocular micrometer. Invasive foci consisted of isolated cells or cell clusters, or appeared as a tongue-like projection of tumor through the basement membrane of the duct of ductal carcinoma in situ (DCIS). The mean number of invasive foci was 3, and the mean size was 0.6 mm. We found that high nuclear grade and predominant comedo subtype of DCIS components were 57.1% and 46.4%, respectively. Twenty-four cases (86%) demonstrated necrosis of DCIS components. Microinvasion was often associated with periductal stromal reaction (71.5%) and/or a lymphocytic infiltration (78.6%). All patients, excluding two, received axillary resection (the mean number of lymph nodes examined per case was 12), and none had lymph node metastasis. The positive expression of ER and PR strongly related to low grade nuclei and non-comedo subtype; however, the positive expression of HER-2 and P53 related to high grade nuclei and comedo subtype (P<0.01). Ki-67 expression was significantly higher in the high grade nuclei group than in the low grade group (P<0.01). Our study suggested that high nuclear grade and comedo DCIS were more aggressive and more common with microinvasion, and that microinvasion is more likely to be multifocal. 相似文献
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K. Joh S. Aizawa K. Ohkawa T. Morioka T. Oite F. Shimizu S. Batsford A. Vogt 《Virchows Archiv : an international journal of pathology》1994,424(6):587-591
We developed an experimental protocol for planting exogenous antigens with different molecular weights and charges on the constituents of the renal tubulointerstitium. The cationized antigens were injected selectively into the left renal arteries of Wistar rats. Antigen localization was documented by immunohistochemistry on frozen sections. Cationized bovine serum albumin (BSA; 68 kDa, isoelectric point =9.5) localized almost exclusively along the glomerular capillary wall. After application of highly cationic polyethyleneimine, cationized BSA given subsequently was found in a linear distribution along the glomerular capillary wall and along the peritubular capillaries. The fate of highly cationized ovalbumin conjugated with trinitrophenol (TNP-OA), subjected to gel filtration to obtain monomers (42 kDa, isoelectric point >10) differed; it was deposited in a linear pattern on the tubular basement membrane (TBM) and Bowman's capsule, and remained up to 36 h after injection. Noncationized, monomeric TNP-OA (42 kDa, isolectnic point =4.6) showed fine granular deposition in the tubular epithelium exclusively. These findings indicate that the barrier of the glomerular BM acts selectively on antigens with different molecular weights. They either settle on the peritubular capillaries, after passing the glomerular, or reach the urinary space, after which they are reabsorbed by the tubular epithelial cells to reach the TBM. 相似文献
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Indomethacin suppository and aspirin inhalation reduced the amounts of sputum in the patients with bronchiectasis and chronic bronchitis. A 67-year-old woman with bronchiectasis received indomethacin suppository to relieve the lumbar pain. After the start of indomethacin, a reduction in the amount of sputum was observed and the volume of sputum returned to pretreatment levels after the cessation of indomethacin. Levels of cyclooxygenase products in the sputum during indomethacin was also much lower than their levels after discontinuance of indomethacin. A 64-year-old man with chronic bronchitis was also administered inhaled aspirin to control the sputum volume. Both indomethacin suppository and aspirin inhalation reduced the amounts of sputum. In addition to these cases, a 31-year-old woman with bronchial asthma was tried to control the sputum production with indomethacin, but it had no effect on the sputum volume. It is suggested that these drugs may be useful in the treatment of excessive sputum in bronchiectasis and chronic bronchitis. 相似文献
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Shigeo Aizawa Masafumi Suzuki Yasushi Kikuchi Takashi Nikaido Kenji Matsumoto 《Pathology international》1987,37(7):947-954
Seven metastasizing small renal cell carcinomas smaller than 30 mm in the greatest diameter were clinicopathologically studied for a better understanding of their characteristic features as compared to those of small tumors without metastases. Grayish-white infiltrating tumors in gross appearance and alveolar or solid microscopic structure consisting of granular or spindle cells and of atypical nuclei were suggestive of having metastases. Two tumors which had positive reactions to the lower nephron markers such as SB A, PNA, and/or DBA were considered to be of lower nephron origin and displayed poor prognosis. ACTA PATHOL. JPN. 37: 947–954, 1987. 相似文献
50.
Morse MA Garst J Osada T Khan S Hobeika A Clay TM Valente N Shreeniwas R Sutton MA Delcayre A Hsu DH Le Pecq JB Lyerly HK 《Journal of translational medicine》2005,3(1):9-8
BACKGROUND: There is a continued need to develop more effective cancer immunotherapy strategies. Exosomes, cell-derived lipid vesicles that express high levels of a narrow spectrum of cell proteins represent a novel platform for delivering high levels of antigen in conjunction with costimulatory molecules. We performed this study to test the safety, feasibility and efficacy of autologous dendritic cell (DC)-derived exosomes (DEX) loaded with the MAGE tumor antigens in patients with non-small cell lung cancer (NSCLC). METHODS: This Phase I study enrolled HLA A2+ patients with pre-treated Stage IIIb (N = 4) and IV (N = 9) NSCLC with tumor expression of MAGE-A3 or A4. Patients underwent leukapheresis to generate DC from which DEX were produced and loaded with MAGE-A3, -A4, -A10, and MAGE-3DPO4 peptides. Patients received 4 doses of DEX at weekly intervals. RESULTS: Thirteen patients were enrolled and 9 completed therapy. Three formulations of DEX were evaluated; all were well tolerated with only grade 1-2 adverse events related to the use of DEX (injection site reactions (N = 8), flu like illness (N = 1), and peripheral arm pain (N = 1)). The time from the first dose of DEX until disease progression was 30 to 429+ days. Three patients had disease progression before the first DEX dose. Survival of patients after the first DEX dose was 52-665+ days. DTH reactivity against MAGE peptides was detected in 3/9 patients. Immune responses were detected in patients as follows: MAGE-specific T cell responses in 1/3, increased NK lytic activity in 2/4. CONCLUSION: Production of the DEX vaccine was feasible and DEX therapy was well tolerated in patients with advanced NSCLC. Some patients experienced long term stability of disease and activation of immune effectors. 相似文献