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Cancer cells elaborate metalloproteinases which may play a role in invasion and metastasis. The serum level of the M(r) 72,000 type IV collagenase (MMP-2) was measured in 87 lung cancer patients. Stage IV cancer levels were significantly elevated (P less than 0.0001) compared to normal sera. A significant difference (P less than 0.01) was found between enzyme levels in the presence versus the absence of distant metastasis. For 29 patients treated with combination chemotherapy, a positive relationship was noted between response failure and elevated enzyme levels. Serum metalloproteinase levels may provide information relevant to prognosis as well as treatment decisions.  相似文献   
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The effect of 4 mg oral naloxone on preoperative gastric volume and pH of gastric aspirate was studied in a double-blind, randomized study. Twenty patients received 10 ml of naloxone (4 mg) mixed with 10 ml of orange juice, and 20 patients received 10 ml of isotonic saline mixed with 10 ml of orange juice, 2 h before surgery. Gastric content was obtained immediately after intubation of the trachea. No significant difference in gastric volume and pH of gastric aspirate was found between the two groups. It is concluded that naloxone does not affect gastric emptying and gastric acid secretion to a degree great enough to protect against aspiration of gastric contents into the lungs.  相似文献   
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Murine fibrosarcoma cell lines transduced with retroviral vectors containing the murine interleukin 6 (IL-6) gene constitutively secreted IL-6. When injected s.c. into normal mice these IL-6-secreting tumors exhibited reduced tumorigenicity. This reduced tumorigenicity was not seen in nude or irradiated mice, implicating a T-cell-dependent, radiosensitive host response activated by the cytokine. Subcutaneous IL-6-secreting tumor did not retard the growth of distant deposits of wild-type tumor in the same host. However, animals rejecting IL-6-secreting tumors exhibited resistance to later challenge with wild-type tumor. When injected i.v. in an experimental metastasis model the IL-6-secreting tumors failed to or were extremely inefficient in giving rise to pulmonary nodules; this was observed in both normal and immunoincompetent mice, implicating a second, nonimmune mechanism affecting the growth of the tumor modified to secrete IL-6.  相似文献   
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Tissue microdissection is an important method for the study of disease states. However, it is difficult to perform high-throughput molecular analysis with current techniques. We describe here a prototype version of a novel technique (expression microdissection) that allows for the procurement of desired cells via molecular targeting. Expression microdissection (xMD) offers significant advantages over available methods, including an increase in dissection speed of several orders of magnitude. xMD may become a valuable tool for investigators studying cancer or other disease states in patient specimens and animal models.  相似文献   
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