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971.
Professionals have suggested that aggressiveness, substance abuse, and criminality contribute to poor outcomes after brain injury. There is considerable research regarding post-injury aggressive behaviour, but limited information concerning criminal behaviour and alcohol use patterns. With a sample of 327 patients varying in severity of traumatic brain injury, the present investigation examined alcohol use patterns, arrest histories, behavioural characteristics, and psychiatric treatment histories. Relative to the uninjured population, analysis revealed relatively high incidence of heavy drinking, both pre- and post-injury, among patients with a history of arrest. Increases in abstinence rates were found regardless of arrest history. In addition, a history of arrest was associated with a greater likelihood of psychiatric treatment. Findings also indicated relatively high levels of aggressive behaviours. Discussion focuses on implications for evaluation, rehabilitation, and future research. 相似文献
972.
M Beaudet-Miller R Zhang J Durkin W Gibson AD Kwong Z Hong 《Canadian Metallurgical Quarterly》1996,70(11):8081-8088
We previously identified a minimal 12-amino-acid domain in the C terminus of the herpes simplex virus type 1 (HSV-1) scaffolding protein which is required for interaction with the HSV-1 major capsid protein. An alpha-helical structure which maximizes the hydropathicity of the minimal domain is required for the interaction. To address whether cytomegalovirus (CMV) utilizes the same strategy for capsid assembly, several glutathione S-transferase fusion proteins to the C terminus of the CMV assembly protein precursor were produced and purified from bacterial cells. The study showed that the glutathione S-transferase fusion containing 16 amino acids near the C-terminal end was sufficient to interact with the major capsid protein. Interestingly, no cross-interaction between HSV-1 and CMV could be detected. Mutation analysis revealed that a three-amino-acid region at the N-terminal side of the central Phe residue of the CMV interaction domain played a role in determining the viral specificity of the interaction. When this region was converted so as to correspond to that of HSV-1, the CMV assembly protein domain lost its ability to interact with the CMV major capsid protein but gained full interaction with the HSV-1 major capsid protein. To address whether the minimal interaction domain of the CMV assembly protein forms an alpha-helical structure similar to that in HSV-1, peptide competition experiments were carried out. The results showed that a cyclic peptide derived from the interaction domain with a constrained (alpha-helical structure competed for interaction with the major capsid protein much more efficiently than the unconstrained linear peptide. In contrast, a cyclic peptide containing an Ala substitution for the critical Phe residue did not compete for the interaction at all. The results of this study suggest that (i) CMV may have developed a strategy similar to that of HSV-1 for capsid assembly; (ii) the minimal interaction motif in the CMV assembly protein requires an alpha-helix for efficient interaction with the major capsid protein; and (iii) the Phe residue in the CMV minimal interaction domain is critical for interaction with the major capsid protein. 相似文献
973.
CN Baxevanis GJ Reclos AD Gritzapis GV Dedousis I Missitzis M Papamichail 《Canadian Metallurgical Quarterly》1993,72(2):491-501
BACKGROUND: Human natural killer (NK) cells mediate spontaneous cytotoxicity against tumor cells and represent the main precursors of lymphokine-activated killer (LAK) cell activity. A comparison of some aspects of NK and LAK cell activity was undertaken in 85 preoperative patients with breast cancer and 75 healthy donors. METHODS: NK cell activity (tested in 18-hour cultures of effector peripheral blood mononuclear cells [PBMC] with K562 or MOLT-4 tumor target cells) was significantly diminished in these patients as it was the fully mature LAK cell activity (i.e., interleukin-2 (IL-2)-induced cytotoxicity in PBMC) against NK resistant target cells. Using immunoenzymatic methods we showed that the reduced NK cell activity was due to abnormally high levels of prostaglandin E2 (PGE2) produced by monocytes in culture. RESULTS: PGE2 was found to suppress the production of IL-2 in these cultures. Removal of monocytes from PBMC restored to almost normal levels the deficient NK and LAK cell activity in patients with breast cancer and was also associated with a normalization in the levels of PGE2 and IL-2. Indomethacin and gamma-interferon (IFN-gamma) increased the NK and LAK cell activity in these patients up to the levels of healthy donors. When highly purified CD56+ cells (obtained by an immunomagnetic isolation technique) were used as effector cells, no differences in LAK cell activity could be noticed between healthy donors and patients with cancer. FACS and northern blot analyses demonstrated a PGE2-mediated down-regulation of IL-2 receptor (IL-2R) expression on CD56+ cells that correlated with reduced LAK cell activity. This inhibitory effect of PGE2 was noticeable in long-term LAK cultures and was abrogated in the presence of IFN-gamma or indomethacin. CONCLUSION: This study may have important implications in the potentiation of NK and LAK cell activity for immunotherapeutic protocols in patients with breast cancer. 相似文献
974.
We reviewed the literature addressing the use and complications associated with low-viscosity distention fluids in urologic and hysteroscopic procedures. The possible causes of fluid complications included elevated intrauterine pressure, myometrial invasion, prolonged operating time, and operative trauma to the cervix or uterine body. Physiologic electrolyte solutions create only fluid overload, and treatment requires cardiovascular support and diuresis. Nonelectrolytic solutions result in acute dilutional hyponatremia, which has been referred to as the transurethral resection of the prostate syndrome. Treatment requires diuresis and a rapid, controlled return of the serum sodium level to 120-130 mmol. These complications can be minimized with proper use of equipment and careful monitoring of fluid volumes. To recognize and treat them, the surgeon must be knowledgeable about the fluid being used and the difficulties it may cause. 相似文献
975.
AD Spiegel 《Canadian Metallurgical Quarterly》1993,93(3):190-193
Abomasal fistulae resulting from right paramedian abomasopexy in eight adult dairy cattle were treated by primary closure of the abdominal wall after surgical resection of the fistulae. The median elapsed time from the abomasopexy to recognition of fistula formation was 16 days (range, 10 to 90 days). All cows had normal electrolyte values, and five cows had mildly increased base excess values (range = 4.0 to 7.8 mEq/L). Surgery was performed with the cows in dorsal recumbency using general anesthesia. The fistulated tissue was resected and the abomasum and body wall were closed primarily. One or two layers of appositional sutures using #2 or #3 polyglactin 910 were used to close the body wall. Mean surgical time was 2.2 hours (range, 1.8 to 2.9 hours). Two cows were lost to follow-up. Five of the remaining six cows returned to production (range, 5 to 30 months). Primary closure of the abdominal wall should be considered in the surgical repair of abomasal fistulae in cows that do not have diffuse peritonitis. 相似文献
976.
977.
A modified method of applying ZnSO4 to the olfactory mucosa is described. Treated rats experienced severe nasal congestion that cleared within 24 h; more persistent morbidity did not occur. Nonpregnant females observed with male intruders 24 h following ZnSO4 showed no alterations in behavior other than a reduction in anogenital sniffing, indicating that they were not hypoactive or irritable. In other experiments, lactating females were observed in a hole-board apparatus; 2 days posttreatment anosmia was confirmed in 80% of bilaterally ZnSO4-treated females by the absence of preference for pup odors. After bilateral but not unilateral ZnSO4 treatment, initially activity scores and nose pokes were equivalent in all groups, but later they both were lower than in controls, probably due to a more rapid habituation to the novel apparatus. We conclude that intranasal ZnSO4 by small-volume spray is a useful experimental tool. 相似文献
978.
979.
980.