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41.
Mary Steidl Matsui Isabella Illarda Nianci Wang Vincent A. DeLeo 《Experimental dermatology》1993,2(6):247-256
Abstract Several lines of evidence implicate protein kinase C (PKC) in the development of basal cell and squamous cell carcinomas, tumors which originate from epidermal keratinocytes. To examine PKC in a model relevant to human skin, we exposed normal human epidermal keratinocytes (NHEK) in serum-free media to a variety of PKC agonists and antagonists. NHEK PKC activity increased up to 10-fold within the 1st hour of exposure to tetradecanoyl phorbol acetate (TPA), and gradually returned to control values within 72 h. TPA-induced PKC activity was enhanced by pretreatment of cultures with protein and RNA synthesis inhibitors. TPA-induced growth arrest and differentiation was antagonized by staurosporine. Down-regulation by bryostatin pretreatment blocked TPA-stimulated differentiation. Our overall conclusion is that activation of PKC in cultured human keratinocytes is required for differentiation. These results are crucial to the analysis of compounds suspected of promoting or inhibiting epidermal tumors. 相似文献
42.
Lacerations of the inferior vena cava resulting from blunt external trauma are relatively rare, but extremely serious. The high lethality is due to the difficulty in diagnosis and technical problems with repair, particularly if the injury is located above the renal veins. During a 12-month period seven patients with inferior vena cava laceration were seen, of whom two presented with laceration of the inferior vena cava above the diaphragm. Both had a deceleration injury while wearing seatbelts. The clinical presentation was similar. The etiology is discussed. Caval continuity should be repaired because acute sudden occlusion at the suprahepatic level is incompatible with survival. Median sternotomy is advised, moreover it provides good exposure for eventual cannulation. 相似文献
43.
Prolactin and growth hormone receptors 总被引:2,自引:0,他引:2
44.
45.
John D. Hughes MD Changyi Chen MD Samer G. Mattar MB ChB Ayten Someren MD Beverly Noe BS Carolyn R. Suwyn BS Alan B. Lumsden MD 《Annals of vascular surgery》1996,10(2):123-130
Hypothermia and preservative perfusates have been used to decrease ischemic renal injury. This study was performed to identify the preservative function of perfusates independent of the effects of hypothermia. Rats underwent 45 minutes of renal ischemia. Rectal and renal parenchyma temperatures were monitored and maintained within 1° C of normal. Perfusates were University of Wisconsin solution (UW), Euro-Collins solution, normal saline solution, and Ringer's lactate solution. A nonperfused ischemic control and a nonischemic control group were also evaluated. Parameters evaluated included serum creatinine and blood urea nitrogen levels, renal ischemic injury grade, renal weight, and gross appearance of the injured kidney. Rats treated with UW solution were found to have a significantly lower creatinine, blood urea nitrogen, and injury grade than the other three perfused groups. The external gross appearance of the UW-treated kidneys was normal, whereas that of the other groups demonstrated moderate to severe injury. Although the mean right/left renal weight difference of the UW-treated group was lower than that of the other three groups, this was not statistically significant. Under normothermic conditions in rats, UW solution affords significant renal protection from ischemia. Euro-Collins, normal saline, and Ringer's lactate solutions display no significant protective effect.Presented at the Twentieth Annual Meeting of the Peripheral Vascular Surgery Society, New Orleans, La., June 10, 1995. 相似文献
46.
47.
M J Ahern MD FRACP M Wetherall BEd A Leslie MB BS R H James BSc P J Roberts-Thomson PhD FRACP G C Rennie BA BSc MA 《International journal of clinical practice》1992,46(4):229-233
The elderly (age >65 years) are more vulnerable to side-effects induced by non-steroidal anti-inflammatory drugs (NSAIDs). We therefore performed a double-blind comparative study of ketoprofen SR and sulindac in patients with active rheumatoid arthritis, 65 years of age or older. Sulindac was chosen because of its possible renal sparing effects, and ketoprofen SR because of its short half life and sustained release delivery system. Eighty patients were entered. More patients withdrew from the study due to side-effects in the sulindac group; both treatment groups had a high incidence of side-effects during this study and during previous exposure to other NSAIDs, demonstrating that the elderly are susceptible to side-effects from NSAIDs. 相似文献
48.
Daniel W. Walsh Vincent B. Ho Michael F. Haggerty 《Journal of magnetic resonance imaging : JMRI》1997,7(2):312-315
Mycotic aneurysms of the abdominal aorta are potentially fatal but uncommon. We report the MRI and MRA features of an abdominal aortic mycotic aneurysm in a patient who presented with nonspecific low back pain. By delineating the saccular nature of the aneurysm and identifying the coexistence of vertebral enhancement, MRI was crucial for the final diagnosis. A potential pitfall of contrast-enhanced MRA is also demonstrated. 相似文献
49.
N. D. Edwards MB BS FRCAnaes M. Hartley MB P. Clyburn MB BS FRCAnaes M. Harmer MB BS FRCAnaes 《Anaesthesia》1992,47(5):435-437
A double-blind randomised study was performed to assess the value of the addition of pethidine 50 mg to the initial dose of bupivacaine given for epidural analgesia in labour. Forty-nine patients received either 1 ml of saline (n = 24), or 50 mg of pethidine (n = 25), added to 9 ml of 0.25% bupivacaine as an initial injection for intrapartum epidural analgesia. There was a significant increase in the mean duration of analgesia in the pethidine group. However, pethidine did not increase the speed of onset of analgesia, or improve the quality of analgesia. 相似文献
50.