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991.
EJ Friedman CR Orth KA Brewton S Ponniah RB Alexander 《Canadian Metallurgical Quarterly》1997,158(4):1585-1588
PURPOSE: We wished to determine if cryosurgical ablation of the normal ventral prostate of Copenhagen rats confers protective immunity against a subsequent challenge with Dunning R3327 MatLyLu prostatic adenocarcinoma. In human melanoma, tumor antigens have been characterized as normal cellular proteins. We reasoned that cryosurgical ablation of the normal prostate along with immunostimulatory adjuvants might release prostatic antigens to the immune system engendering an immune response and rendering rats immune to prostatic cancer cells. MATERIALS AND METHODS: On day 0, Copenhagen rats underwent cryosurgical ablation of the normal ventral prostate, cryosurgery and intraprostatic injection of Complete Freund's Adjuvant (CFA), CFA injection alone, or laparotomy alone. On day 21, animals received a subcutaneous challenge of MatLyLu tumor cells. Tumor dimensions were recorded at regular intervals by a single blinded investigator. RESULTS: Animals receiving cryosurgical ablation of the normal ventral prostate or intraprostatic CFA developed tumors more frequently than animals receiving laparotomy alone and the effect was statistically significant if animals received both cryosurgical ablation of the prostate and intraprostatic CFA (3 experiments, 1 x 10(4) MatLyLu cells), total number with tumors/total number challenged: laparotomy alone 3/17, cryosurgical ablation 7/17, cryosurgery plus CFA 10/16 (p = 0.013 versus laparotomy, Fisher's exact test), CFA alone 9/17. CONCLUSIONS: Cryosurgical ablation of the normal rat ventral prostate and intraprostatic CFA does not protect against and can enhance the tumorigenicity of MatLyLu prostatic cancer cells at distant sites. This could be occurring through specific immunologic effects or non-specific mechanisms induced by cryosurgery and CFA. 相似文献
992.
993.
KA Wesnes MB Walker LG Walker SD Heys L White R Warren O Eremin 《Canadian Metallurgical Quarterly》1997,84(4):493-495
BACKGROUND: Considerable interest and concern have been expressed about junior doctors' hours. This study was carried out to evaluate the emotional and cognitive effects of a weekend on call in a surgical ward. METHODS: Ten surgical house officers were assessed, in counterbalanced design, on four Monday mornings, twice after a weekend off duty and twice after a weekend on call. Cognitive functioning was assessed using the Cognitive Drug Research computerized cognitive assessment system, and emotional state was evaluated by means of the Aberdeen Mood Rating Scale. RESULTS: Following a weekend on call, significant impairment in concentration, speed and power was observed, and the doctors felt less confident, less energetic and more confused. Impaired attention, working memory, long-term memory and confusion were most closely correlated with number of hours worked on Sunday, and tiredness and confusion were related to number of hours slept. CONCLUSION: A weekend on call has significant deleterious effects on cognitive performance and mood. The findings have implications for staffing levels and the design of duty rosters. 相似文献
994.
Contrast material-enhanced computed tomographic (CT) scans obtained over a 10-year period in 66 patients with metastases to the pancreas were retrospectively reviewed. The primary tumors most commonly responsible for these metastases were renal cell carcinoma (30.3%) and bronchogenic carcinoma (22.7%). Metastases showed no predilection for any particular part of the pancreas. The majority (75.8%) of metastases appeared as tumors with discrete margins, and most of these tumors were round or ovoid with smooth borders. Over three-fourths of the lesions demonstrated enhancement (usually heterogeneous). Vascular involvement was uncommon. In those patients in whom pancreatic metastases were discovered some time after the primary tumor was identified, the interval ranged from 2 to 295 months, with the longest mean interval (120.2 months) being associated with metastatic tumors from renal cell carcinoma. The appearance of these tumors at CT--predominantly hyperattenuating masses, often with nonenhancing internal components--was similar to that of primary renal cell carcinoma. In most pancreatic metastases, however, clinical information in conjunction with CT characteristics such as multiplicity of tumors or hypervascularity permit differentiation of metastases from primary neoplasm. When diagnosis of a pancreatic neoplasm is uncertain, percutaneous biopsy often permits histologic confirmation of the tumor type. 相似文献
995.
The purpose of this study is to review published data regarding gender differences in cardiac electrophysiology and in the occurrence of clinical arrhythmias. ECG differences between men and women include a faster resting heart rate in women, a longer corrected QT interval, and a lower QT dispersion than in men. The faster resting heart rate in women appears to be primarily related to differences in physical conditioning. The mechanism for the longer corrected QT interval in women is not completely known, but does not appear to be related to acute effects of estrogen or progesterone or differences in autonomic innervation. Women also appear to have a lower incidence of atrial fibrillation, a difference in the age distribution of supraventricular tachycardia, and a lower incidence of sudden death than men. Much of the lower incidence of sudden death in women may relate to a difference in the prevalence of coronary artery disease, but other factors such as inherent differences in repolarization, which may be reflected by a gender difference in the corrected QT interval, also may be operative. The paradox of a longer corrected QT interval and higher incidence of torsades de pointes, but lower population-based incidence of sudden death in women, has not been completely resolved. Further studies will be required to help better understand the basic mechanisms involved in gender differences in electrophysiology and arrhythmias and determine the extent to which these differences have implications for clinical management of cardiac arrhythmias. 相似文献
996.
997.
MP Wentland RB Perni PH Dorff RP Brundage MJ Castaldi JA Carlson TR Bailey SC Aldous PM Carabateas ER Bacon RK Kullnig DC Young MG Woods SD Kingsley KA Ryan D Rosi ML Drozd FJ Dutko 《Canadian Metallurgical Quarterly》1997,15(1):25-38
Despite the long history in medicine, the pathophysiological mechanism(s) of seasonal affective disorder (SAD) remain largely unknown. By employing a meta-analytic methodology, the authors of this study attempted to verify the validity of different pathophysiological mechanism(s) proposed for SAD. The findings showed that for phototherapy of medium light intensity, a combination of morning-evening therapy regime yielded the best therapeutic effect, and the antidepressant effect of the morning-evening light regime was superior to a single pulse of light administered at other times of day. Furthermore, the data showed that the antidepressant effect of a single pulse of light was similar for morning, midday, and evening light. These findings supported the photon-count hypothesis and refuted the proposed photoperiod, melatonin, and phase-shifting models of SAD. 相似文献
998.
Brain tissue mRNA was amplified using polymerase chain reaction (PCR) with eight overlapping sets of primers that span the cDNA coding sequence for the human placental insulin receptor. Only the A isoform (lacking exon 11) of the receptor was detected. No difference was found in the predicted amino acid sequence of brain derived insulin receptor cDNA compared with the receptor from human placenta. A silent polymorphism was detected at nucleotide position 1698 (amino acid 523), confirming that mRNA corresponding to both alleles of the human brain receptor was sequenced. Our findings indicate that the unique glycosylation properties of brain insulin receptors do not stem from differences in primary structure, but rather are due to tissue-specific differences in post-translational processing. 相似文献
999.
1000.
WC Levine RW Bennett Y Choi KJ Henning JR Rager KA Hendricks DP Hopkins RA Gunn PM Griffin 《Canadian Metallurgical Quarterly》1996,173(5):1263-1267
From February through April 1989, four outbreaks of staphylococcal food poisoning in the United States were associated with eating mushrooms canned in the People's Republic of China (PRC). In the four outbreaks, 99 persons who ate at a suspect facility developed gastrointestinal symptoms within 24 h, including 18 who were hospitalized. Illness was associated with eating mushrooms at a university cafeteria (relative risk [RR] = 53.0), a hospital cafeteria (RR = 13.8), a pizzeria (odds ratio [OR] = infinity), and a restaurant (OR = infinity) (all P < .0001). Staphylococcal enterotoxin A was found by ELISA in mushrooms at the sites of two outbreaks and in unopened cans from the three plants thought to have produced mushrooms implicated in outbreaks. These investigations led to multistate recalls and a US Food and Drug Administration order to restrict entry into the United States of all mushrooms produced in the PRC; until this action, the United States imported approximately 50 million pounds yearly. 相似文献