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991.
The impact of recombinant human tumour necrosis factor-alpha (1 microgram kg-1 to 1 mg kg-1; 6.6 x 10(6) U mg protein-1) on blood flow, oxygen consumption and growth of a moderately TNF-sensitive rat tumour (DS-carcinosarcoma) was studied. Tumour growth was stimulated at low TNF doses (1 and 10 micrograms kg-1) and significantly retarded at higher TNF dose levels (0.1 and 1 mg kg-1). Growth changes were concomitant with variations in oxygen consumption, lactate release and acidification of the metabolic micromilieu. Both single and repeated application of low TNF doses (1-10 micrograms kg-1 i.v.) increased tumour perfusion whereas single administration of high TNF dose levels (0.1-1 mg kg-1 i.v.) reduced tumour blood flow. After repeated application of high TNF doses tumours shrank to such small sizes that perfusion measurements could not be performed within the observation period of two weeks. It is concluded that TNF effects on solid tumours are at least partially mediated by changes in tumour perfusion. Thus, an altered tumour sensitivity towards other treatment modalities, e.g. irradiation, chemotherapy or hyperthermia, can be expected after TNF therapy. A beneficial TNF effect would critically depend on the dose level employed and on the sequence and timing of various combination regimes. 相似文献
992.
Excretory/secretory antigen of Toxocara canis: recognition profiles of polyclonal and larvicidal monoclonal antibodies 总被引:1,自引:1,他引:0
Summary Five monoclonal antibodies against the excretory/secretory (E/S) antigen of Toxocara canis were obtained and characterized. Immunoprecipitating activity was demonstrated in an in-vitro micropre-cipitating assay using live T. canis larvae. Their capacity to kill larvae was also shown in an in-vitro assay. Two zones of reactivity were observed in 7.5 and 12.5% SDS-PAGE (177-77 kD, 43-15 kD) of immunoprecipitates of human and mouse positive polyclonal anlisera. The murine monoclonal antibodies showed a common pattern of reactivity with the proteins in the 177-77 kD range. 相似文献
993.
Tissue-specific regulation of pyroglutamate aminopeptidase II activity by thyroid hormones 总被引:2,自引:0,他引:2
Among the enzymes capable of degrading thyrotropin-releasing hormone (TRH) in vitro, two pyroglutamate aminopeptidases (PGA) are specific for TRH: thyroliberinase, a seric enzyme and PGAII, a membrane-bound peptidase. The effect of thyroid hormone status on the activity of these enzymes was evaluated in serum and various tissues. Only in adenohypophysis, triiodothyronine treatment increased PGAII to 376% of control; hypothyroidism produced the reverse effect (decrease to 23% of control). As previously reported, similar changes were observed for thyroliberinase. TRH degradation at the adenohypophysis level may participate in the negative feedback control of thyroid hormones. 相似文献
994.
A novel hybridoma antibody (PASE/4LJ) to human prostatic acid phosphatase suitable for immunohistochemistry 总被引:2,自引:0,他引:2
A M Haines S E Larkin A P Richardson R W Stirling E Heyderman 《British journal of cancer》1989,60(6):887-892
A murine monoclonal antibody PASE/4LJ to prostatic acid phosphatase (PAP) was used to immunostain a wide variety of sections of benign and malignant tissues (654 blocks). Non-neoplastic adult and fetal prostatic glands, primary and metastatic prostatic carcinomas, and scattered cells in prostatic and penile urethra were positive. Rat, dog and rabbit prostates were negative. Nine of 400 tumours of non-prostatic origin showed some positivity: 6/36 carcinoids, 1/9 islet cell tumours, 1/55 ovarian adenocarcinomas (serous) and one carcinosarcoma of the lung (epithelial portion). Positive staining was seen in islet cells in 4/5 specimens of normal pancreas, and in 4/9 blocks of normal pancreas surrounding a pancreatic tumour. Loops of Henle, maculae densae, and distal tubules in 10/10 fetal and 2/9 adult kidneys were also positive, with proximal tubules and collecting ducts negative. All other 159 blocks of non-neoplastic adult and fetal tissues were negative. The antibody was also affinity purified from ascitic fluid, and shown not to inhibit the enzyme activity of prostatic acid phosphatase. 相似文献
995.
Noninvasive examination of the venous system in the leg: presclerotherapy evaluation 总被引:1,自引:0,他引:1
H S Fronek 《The Journal of dermatologic surgery and oncology》1989,15(2):170-173
Sclerotherapy of varicose veins and telangiectasia should be preceded by a directed medical history and physical examination. Factors including the presence of significant venous disease should prompt a more extensive evaluation. Of the physical examination techniques and noninvasive technologies available, Doppler ultrasound provides the most pertinent information, but the potential uses of each method are described. 相似文献
996.
997.
998.
999.
Summary. In this study, we have examined our records for the isolation of Candida tropicalis from clinical specimens of patients with heterogeneous clinical presentations during the past 5 years. We have found that this species ranks third among all yeasts in frequency of isolation from clinical specimens and that the trend of recovery from the specimens is rising over the years. The isolation rate of C. tropicalis was highest from urine specimens (36%) followed by respiratory specimens (22%). The frequency of isolation of C. tropicalis from vaginal specimens was relatively high (14%), however the trend was declining over the years. In general, the high recovery of Candida tropicalis from clinical specimens of patients with variable disease supports the views of this organism being a major pathogen.
Zusammenfassung. Die Studie basiert auf einer Durchsicht der Patientenarchive der letzten fünf Jahre auf die Isolationshäufigkeit von Candida tropicalis aus klinischen Untersuchungsmaterialien von Patienten mit unterschiedlichen klinischen Krankheitsbildern. Diese Hefeart war die dritthäufigste mit steigender Tendenz über die Jahre. Die Isolierungsrate von C. tropicalis war am höchsten aus Urin (36%), gefolgt von Respirationstrakt-Materialien (22%). Die Isolationshäufigkeit aus dem hinteren Scheidengewölbe war relativ hoch (14%), nahm jedoch mit den jahren ab. Allgemein unterstreicht die hohe Isolationsrate von C. tropicalis aus klinischen Untersuchungsmaterialien die ätiologische Bedeutung dieses Erregers. 相似文献
Zusammenfassung. Die Studie basiert auf einer Durchsicht der Patientenarchive der letzten fünf Jahre auf die Isolationshäufigkeit von Candida tropicalis aus klinischen Untersuchungsmaterialien von Patienten mit unterschiedlichen klinischen Krankheitsbildern. Diese Hefeart war die dritthäufigste mit steigender Tendenz über die Jahre. Die Isolierungsrate von C. tropicalis war am höchsten aus Urin (36%), gefolgt von Respirationstrakt-Materialien (22%). Die Isolationshäufigkeit aus dem hinteren Scheidengewölbe war relativ hoch (14%), nahm jedoch mit den jahren ab. Allgemein unterstreicht die hohe Isolationsrate von C. tropicalis aus klinischen Untersuchungsmaterialien die ätiologische Bedeutung dieses Erregers. 相似文献
1000.
为探讨脂质过氧化损伤及自由基在新生儿硬肿症发病机理中的作用,将观察对象分为疾病组和对照组,疾病组于入院时,对照组于出生后1周内取静脉血检测血浆脂质过氧化物及红细胞超氧化物歧化酶含量。 相似文献