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42.
Researchers have differentiated sons of alcoholics (SOA's) from sons of nonalcoholics (non-SOA's) on various measures of physiological activity that appear to be related to the SOA's increased vulnerability to developing alcohol problems. This article summarizes major findings in the literature and discusses the implications of risk-related physiological characteristics for the future development of alcohol problems. SOA's tend to show signs of physiological activity associated with anxiety states, such as increased heart rate in response to stressful stimuli. Studies also demonstrate that SOA's differ greatly from non-SOA's in their response to alcohol. Drinking alcohol dramatically reduces SOAs' reactivity to both stressful and nonstressful stimuli. Additionally, SOA's appear to be less sensitive to alcohol's intoxicating and impairing effects. However, studies also suggest that some SOA's may experience more of alcohol's rewarding effects for a brief period after drinking. Increased stress-dampening and reduced responsiveness to alcohol's negative effects also appear to predict the development of future alcohol problems and may reflect important vulnerabilities in SOA's. 相似文献
43.
DeLima M Amato RJ Jackson A Tu SM Banks M Finn L Ellerhorst J 《Cancer biotherapy & radiopharmaceuticals》1997,12(6):365-370
We have completed a phase I/II trial to evaluate the toxicity and efficacy of the combination of gamma interferon and 5-fluorouracil in metastatic renal cell carcinoma. Gamma interferon was administered at a weekly dose of 100 micrograms. 5-fluorouracil was given as a 5 day continuous infusion days 1-5 of each 21 day cycle. In the phase I portion of the trial, the gamma interferon dose was held constant, while the 5-fluorouracil was escalated from 500 to 800 mg/m2/day. Serum neopterin and beta 2 microglobulin were measured prior to and 48 hours after each dose of gamma interferon for the first six weeks of treatment. Dose limiting toxicity was not encountered in the phase I part of the trial; therefore the phase II study was initiated at the 800 mg/m2/day dose of 5-fluorouracil. No responses were seen among 34 patients treated on the phase II trial. Forty-six percent of patients experienced disease stabilization and the remainder progressed through treatment. In the phase I trial, increments in neopterin and beta 2 microglobulin levels differed significantly between patients treated with lower and higher doses of 5-fluorouracil. We conclude that the addition of 5-fluorouracil to gamma interferon does not appear to enhance the cytokines clinical activity. Incremental increases in macrophage activation markers with escalating 5-fluorouracil doses suggests a role for 5-fluorouracil beyond its usual proposed cytotoxic activity and warrants further investigation into potential immunologic effects of this drug. 相似文献
44.
Alcoholics have previously been found to be more sensitive to painful stimulation than controls, and more sensitive to the pain-reducing effects of alcohol. The present study was designed to examine these effects in men at high familial-genetic risk for alcoholism and controls. Subjects were assigned to one of four alcohol doses [0.135 (active placebo), 0.50, 0.75, or 1.00 ml 95% USP alcohol/kg body weight]. Ratings of the amount of discomfort and pain experienced during an aversive shock procedure were taken immediately post-shock, both while subjects were sober and after they had consumed one of the four alcohol doses. High risk men were found to rate the experience of the shock as more uncomfortable and painful overall than the low risk controls. Pharmacologically significant levels of alcohol were found to reduce or eliminate these group differences, suggesting that alcohol has a normalizing effect on pain and discomfort perceptions in high risk men. Only the higher doses of alcohol were found significantly to dampen subjects' shock rating scores. High risk males' increased sensitivity to pain and discomfort, combined with the negatively reinforcing effects of reducing these perceptions at moderate to high alcohol doses, may play a role in predisposing high risk males for the development of alcoholism. 相似文献
45.
Finn RD 《Annals of nuclear medicine》1999,13(6):379-382
Nuclear Medicine is the specialty of medical imaging, which utilizes a variety of radionuclides incorporated into specific compounds for diagnostic imaging and therapeutic applications. During recent years, research efforts in this discipline have concentrated on the decay characteristics of particular radionuclides and the design of unique radiolabeled tracers necessary to achieve time-dependent molecular images. Various oncology applications have utilized specific PET and SPECT radiopharmaceuticals, which have allowed an extension from functional process imaging in tissue to pathologic processes and nuclide directed treatments. One of the most widely recognized advantages of positron emission tomography (PET) is its use of the attractive, positron-emitting biologic radiotracers that mimic natural substrates. However, a major disadvantage is that these substances are relatively short-lived and unable to be transported great distances. At this time, economic considerations and regulatory guidelines associated with the creation of a PET facility, as well as the operational costs of maintaining both the facility and the necessary procedural documentation, continue to create interesting strategic dilemmas. This commentary will focus on the current approach and anticipated impact of pending regulations, which relate to the manufacture and formulation of a variety of PET radiopharmaceuticals used in clinical research and patient management at Memorial Hospital. 相似文献
46.
47.
Sulindac derivatives inhibit growth and induce apoptosis in human prostate cancer cell lines. 总被引:11,自引:0,他引:11
J T Lim G A Piazza E K Han T M Delohery H Li T S Finn R Buttyan H Yamamoto G J Sperl K Brendel P H Gross R Pamukcu I B Weinstein 《Biochemical pharmacology》1999,58(7):1097-1107
We examined the activity of two metabolites of sulindac (a nonsteroidal anti-inflammatory drug), sulindac sulfide and sulindac sulfone (exisulind, Prevatec), and a novel highly potent analog of exisulind (CP248) on a series of human prostate epithelial cell lines. Marked growth inhibition was seen with the BPH-1, LNCaP, and PC3 cell lines with IC50 values of about 66 microM, 137 microM, and 64 nM for sulindac sulfide, exisulind, and CP248, respectively. DNA flow cytometry and 4',6'-diamido-2-phenylindole (DAPI) staining indicated that these three compounds also induced apoptosis in all of these cell lines. Similar growth inhibition also was seen with the PrEC normal human prostate epithelial cell line, but these cells were resistant to induction of apoptosis at concentrations up to 300 microM, 1 mM, and 750 nM of sulindac sulfide, exisulind, and CP248, respectively. Derivatives of LNCaP cells that stably overexpress bcl-2 remained sensitive to growth inhibition and induction of apoptosis by these compounds. In vitro enzyme assays indicated that despite its high potency in inhibiting growth and inducing apoptosis, CP248, like exisulind, lacked cyclooxygenase (COX-1 and COX-2) inhibitory activity even at concentrations up to 10 mM. Moreover, despite variations of COX-1 and COX-2 expression, the three benign and malignant prostate cell lines showed similar sensitivity to growth inhibition and induction of apoptosis by these three compounds. Therefore, sulindac derivatives can cause growth inhibition and induce apoptosis in human prostate cancer cells by a COX-1 and -2 independent mechanism, and this occurs irrespective of androgen sensitivity or increased expression of bcl-2. These compounds may be useful in the prevention and treatment of human prostate cancer. 相似文献
48.
Two hundred and ninety-seven patients with 375 pediatric vascular lesions were followed from 1967 to 1981. By history and physical examination, 96% of childhood vascular lesions can be classified as hemangiomas or malformations. Hemangiomas are often not present at birth (40%), but make their appearance during the first month. A proliferative phase, lasting an average of 3 months, is followed by a slow, but eventually complete involution. A "perfect" cosmetic result is more likely when involution is complete before age 6. Malformations are always present at birth, their growth is commensurate with the patient's, and they never involute. Analysis of clinical characteristics fails to identify a subgroup of hemangiomas destined for early involution. 相似文献
49.
S M Larson J A Carrasquillo D C Colcher K Yokoyama J C Reynolds S A Bacharach A Raubitchek L Pace R D Finn M Rotman 《Journal of nuclear medicine》1991,32(9):1661-1667
Using a newly available model for determining estimates of radiation absorbed dose of radioisotopes administered intraperitoneally, we have calculated absorbed dose to tumor and normal tissues based on a surgically controlled study of radiolabeled antibody distribution. Ten patients with peritoneal carcinomatosis received intraperitoneal injections of the murine monoclonal antibody B72.3 radiolabeled with 131I. Biodistribution studies were performed using nuclear medicine methods until laparotomy at 4-14 days after injection. Surgical biopsies of normal tissues and tumor were obtained. The marrow was predicted to be the critical organ, with maximum tolerated dose [200 rad (2 Gy) to marrow] expected at about 200 mCi (7.4 GBq). In patients with large intraperitoneal tumor deposits, the tumor itself is an important source tissue for radiation exposure to normal tissues. Local "hot-spots" for tumor-absorbed dose were observed, with maximum tumor-absorbed dose calculated at 11,000 rad (11 Gy) per 100 mCi (3.7 GBq) administered intraperitoneal; however, tumor rad dose varied considerably. This may pose serious problems for curative therapy, especially in patients with large tumor burdens. 相似文献
50.