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31.
32.
Inflammatory myofibroblastic tumor (IMT) is a rare neoplasm with unknown malignant potential that has been described in most organ systems. We present the case of a 3-year-old boy who was referred with lower urinary tract symptoms and macroscopic hematuria. An IMT was suspected after clinical, radiological, and surgical work-up, and the diagnosis was confirmed after a partial cystectomy was performed. A bladder-preserving approach is the treatment of choice, but close clinical follow-up is recommended because of the unknown biological behavior of these tumors.  相似文献   
33.
A 60-year old female pseudohermaphrodite with congenital adrenal hyperplasia presented with acute retention of urine and a lower abdominal mass. At laparotomy a large uterus with multiple leiomyomas was removed. Transurethral resection of the obstructing bladder neck revealed benign prostatic hyperplasia. This patient demonstrates that benign prostatic hyperplasia may develop in the presence of androgens from an extratesticular source.  相似文献   
34.
In order to evaluate the initial T stage and tumour grade as predictors of metastatic disease and prognosis in adenocarcinoma of the prostate, 963 patients were reviewed. Of the patients, 41% presented with metastatic disease. Stage T4 tumours were associated with a consistently poor prognosis, and 70% of such patients had demonstrable distant metastases. No patient with TOf local disease had metastases or died of prostate cancer during follow-up. The incidence of metastases was also low in stages T1 and T2. High tumour grade correlated strongly with more advanced disease. Using this information a more cost-effective approach to the staging of prostate carcinoma is proposed.  相似文献   
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The existent labelling materials for studies of antigen--antibody interaction at ultrastructural level, namely ferritin and peroxidase, because of their large molecular size do not fulfill all requirements of excellent markers for electron microscopy (EM). Uranyl acetate has a molecule 354 times smaller than IgG and its uranium atom is electron-dense. These physical characteristics of uranyl acetate make it a labelling material par excellence as described in this article. Quantitative and qualitative studies of Rh antigen-antibody interactions are for the first time presented at the ultrastructural level, and the application of the uranyl-labelled antibody (ULA) method for weak antisera (dilutions 100 to 1000 time higher than the Coombs range of sensitivity) is demonstrated. The ULA method opens a new era for studies of antigens, antibodies and their interactions because it will demonstrate visibly details of the antigen-antibody interaction and is especially suitable for studies of weak antisera.  相似文献   
37.
Testicular peritubular cells produce paracrine mediators which modulate Sertoli cell function. The production of these mediators (P Mod-S) is controlled by androgens suggesting that mesenchymal-epithelial interactions play an important role in androgen action in the testis. We investigated whether mesenchymal cells from the prostate, another androgen target tissue, produce analogous mediators. To this end rat Sertoli cell cultures were exposed to dialyzed spent media derived from testicular peritubular cells, prostatic stromal cells or footsole fibroblasts. It is demonstrated that the effects of spent media from peritubular cells and stromal cells are nearly identical: they stimulate the production of androgen binding protein and transferrin and they inhibit FSH-inducible aromatase activity. The active principle (or principles) involved is non-dialyzable, heat sensitive and trypsin sensitive. Its production is markedly stimulated by androgens. Fibroblast spent media are inactive. It is concluded that mesenchymal tissue derived from different androgen target tissues may produce identical or similar mediators of androgen action acting on epithelial cells.  相似文献   
38.
In order to know as much as possible about human reactions under conditions of extreme ambient air temperatures, and about the ability of men to survive under these conditions and to assist in their own survival, a series of studies was made in which groups of 10 men were exposed to temperature conditions ranging from 96°F. to 104°F. wet bulb (W.B.). Rigid criteria were employed to decide when men should be withdrawn from the test conditions. These were: (a) reaching a rectal temperature of 104°F., (b) suffering from repeated attacks of heat collapse which prevented the subject from standing erect, and (c) suffering a change in temperament and being no longer susceptible to instructions.

At W.B. temperatures of 104°F. and 102°F. the rectal temperatures of the men continued to rise in a straight line until they reached 104°F. There was no tendency for the rectal temperatures to reach a steady state. At 100°F. W.B. there was a definite tendency in the rectal temperatures towards a steady level, but a steady state was not reached until the rectal temperatures had reached 104°F. The same general trend was seen at 98°F., but the time taken to reach a steady state was increased considerably. At 96°F. the rectal temperatures reached a steady level of between 102°F. and 103°F. after about 12 hours of exposure. Superimposed on this steady level was a clearcut circadian rhythm in rectal temperature.

At 104°F. the mean heart rate continued to rise until the men were withdrawn when it had reached 148 beats per minute. In all the other air conditions, the heart rates reached a relatively steady level and the maximum level attained was proportionate to the severity of the air conditions.

The sweat rate increased steadily between 96°F. and 100°F. W.B. from 130 ml./hour to 300 ml./hour. Above 100°F. it increased sharply to reach 800 ml./hour at 102°F. and 875 ml./hour at 104°F. W.B. In contrast to the sweat rate, the hourly rate of water intake did not alter between 96°F. and 100°F. W.B., being approximately constant at 150 ml./hour, but at 102°F. and 104°F. W.B. it rose sharply to 310 ml./hour and 330 ml./hour respectively. The hourly urine output was 95 ml./hour at 96°F. W.B. but fell to 50 ml./hour at 98°F. W.B. and declined further to 35 ml./hour at 104°F. W.B.

At 96°F. and 98°F. W.B. the water intake was approximately equal to the rate of sweat loss, but at 100°F. the sweat rate increased without any rise in water intake, so that the difference was about 150 ml./hour. At 102°F. and 104°F. W.B. the rate of sweating increased sharply. Although the rate of drinking also rose, the difference between intake and output had also increased to about 550 ml./hour at 104°F. W.B.

The curve of the average rate of dehydration is very similar to that representing the rate of sweating. There was little difference in the rate of dehydration between 96°F. and 98°F. W.B., the rate being 80 ml./hour, but at 100°F. it rose to 210 ml./hour. Above 100°F. W.B. the rate of dehydration rose sharply as the rate of water intake lagged further behind the rate of sweating; it was 510 ml./hour at 104°F. W.B.

The main psychological effects were on the men's temperaments. A number of men became aggressive, a few became hysterical, and a few maintained a stoical silence. At 96°F. W.B., when the men remained in the climatic rooms for 48 hours, there were periods of aggressive behaviour which alternated with apathy. Electroencephalograms were done on some subjects. No abnormalities of any kind were evoked or caused by exposure to heat.

The tolerance times before which men, who were initially cool, would not have reached their limit of tolerance to heat were estimated.

  相似文献   
39.
40.
We describe and evaluate a simple method for labelling autologous human platelets with Indium-111-oxine in patients with severe thrombocytopenia. Twenty patients with immune thrombocytopenia and platelet counts ranging from 5 to 119 X 10(9)/1 were investigated. Platelets were isolated from blood by differential centrifugation, residual platelets were repeatedly washed from the red cell layer and buffy coat and labelled with In 111 in saline. A mean of 55% +/- 21 of platelets were harvested from the blood, labelled with 49% +/- 24 efficiency and 15.8 X 10(8) labelled platelets reinjected to the patients. Contamination of the platelets with red cells and plasma was low. The labelled platelets were viable as assessed by in vitro aggregation, recovery in the circulation and mean survival time. This method permits quantitative platelet imaging with autologous labelled platelets in patients with severe thrombocytopenia.  相似文献   
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