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861.
A Heidrich A Schmidtke KP Lesch E Hofmann T Becker 《Canadian Metallurgical Quarterly》1996,21(3):202-206
Disruption of synaptic activity of a number of cerebral structures (e.g., neostriatum, amygdala, and thalamus) produces marked deficits in retention of instrumentally conditioned behaviors. When animals are given a relatively high number of training trials or high intensities of footshock during learning, however, such disruption is considerably less effective. Since there is a close anatomical and functional relationship between the neostriatum and the substantia nigra, it was of interest to determine whether enhanced training with a high level of footshock would prevent the reported amnesic state induced by injections of GABA antagonists into the latter structure. Rats were trained in a one-trial inhibitory task, using 0.2 or 0.4 mA, and then injected with microgram quantities of picrotoxin or bicuculline into the substantia nigra and posterior region of the zona incerta; retention was measured 24 h later. Only those groups that had been injected into the nigra and trained with 0.2 mA showed amnesia. These results support the hypotheses that (a) the normal activity of a set of structures is essential for the development of memory consolidation and (b) after an enhanced learning experience these structures may participate in memory consolidation, but are not necessary for the occurrence of this process. 相似文献
862.
Thinking-aloud protocols provided by Joseph and Patel were reanalyzed to determine the extent to which their conclusions could be replicated by independently developed coding schemes. The data set consisted of protocols from four cardiologists (low domain knowledge = LDK) and four endocrinologists (high domain knowledge = HDK), individually working on a diagnostic problem in endocrinology. The two analyses agree that the HDK physicians related data to potential diagnoses more than did the LDK group and were more focused on the correct diagnostic components. However, the reanalysis found no meaningful difference between the groups in diagnostic accuracy, speed of diagnosis, or the breadth of the search space used to seek a solution. In the reanalysis, the HDK physicians employed more single-cue inference and less multiple-cue inference. The generalizability of results of protocol-analysis studies can be assessed by using several complementary coding schemes. 相似文献
863.
Three patients (1 man, 81 years old; 2 women, 56 and 61 years old) had renal cell cancer and transitional cell cancer in the same kidney, and another patient (female, 77 years old) had renal cell cancer and transitional cell cancer in the ipsilateral ureter. Simultaneous occurrence of renal cell cancer and transitional cell cancer is an extremely rare entity with only 15 cases having been reported. 相似文献
864.
CJ de Haas ME van der Tol KP Van Kessel J Verhoef JA Van Strijp 《Canadian Metallurgical Quarterly》1998,161(7):3607-3615
LPS-binding proteins in plasma play an important role in modifying LPS toxicity. Significant properties have already been attributed to the LPS-binding protein (LBP). It accelerates LPS toxicity as well as incorporation into high-density lipoproteins, leading to neutralization of LPS in serum. A search for other LPS-binding components in serum, using LPS-coated magnetic beads, revealed a new LPS-binding protein. N-terminal microsequencing identified this protein as serum amyloid P component (SAP). Purified SAP bound to smooth and rough types of LPS via the lipid A part. SAP inhibited the binding of FITC-labeled ReLPS (LPS from Salmonella minnesota strain R595) to human monocytes and the ReLPS-induced priming of the oxidative burst of human neutrophils only in the presence of low concentrations of LBP. In search for the LPS binding site of SAP, we found that pep27-39, a 13-mer peptide consisting of amino acids 27-39 of SAP, competitively inhibited the binding of LPS to SAP. In addition, pep27-39 significantly inhibited ReLPS-induced responses in phagocytes in the presence of serum, as well as in human whole blood. Carboxamidomethylated pep27-39 showed an even more pronounced reduction of the ReLPS-induced priming of phagocytes in human blood. Performing gel filtration of FITC-labeled ReLPS incubated with soluble CD14, we showed that SAP could not prevent binding of LPS to soluble CD14, in contrast to pep27-39. The ability of pep27-39 to antagonize specifically the effects of LPS in the complex environment of human blood suggests that pep27-39 may be a novel therapeutic agent in the treatment of gram-negative sepsis. 相似文献
865.
M van Leuven M De Groot KP Shean UO von Oppell PA Willcox 《Canadian Metallurgical Quarterly》1997,63(5):1368-72; discussion 1372-3
BACKGROUND: Over the past decade the incidence of pulmonary disease due to drug-resistant strains of Mycobacterium tuberculosis has increased worldwide. We reviewed our local experience to clarify the benefits and risks of pulmonary resection in the management of drug-resistant strains of Mycobacterium tuberculosis. METHODS: A retrospective review was performed of 62 patients undergoing pulmonary resection for drug-resistant strains of Mycobacterium tuberculosis between January 1990 and November 1995. RESULTS: Fifty-three percent were men and 47% women with an average age of 34 years (range, 16 to 72 years). There was one postoperative death, for a perioperative (30-day) mortality of 1.6%. Sixteen complications occurred in 14 patients for an overall morbidity of 23%. Eighteen of 24 patients (75%) who were persistently sputum positive at the time of operation immediately converted to a negative sputum smear and culture. For all patients who were sputum negative after operation 80% remain relapse-free by actuarial analysis. CONCLUSIONS: We believe that operation plays an important ancillary role in the treatment of drug-resistant strains of Mycobacterium tuberculosis. The operation can be performed with acceptable morbidity and mortality and must be combined with appropriate and well-monitored pre- and postoperative antituberculous drug therapy. 相似文献
866.
867.
TL Wall CM Peterson KP Peterson ML Johnson HR Thomasson M Cole CL Ehlers 《Canadian Metallurgical Quarterly》1997,127(5):376-379
BACKGROUND: About half of certain Asians have a deficiency of the low-Km aldehyde dehydrogenase (ALDH2) isoenzyme. This deficiency results from inheritance of a mutant ALDH2*2 allele. OBJECTIVE: To determine whether Asian Americans with ALDH2*2 alleles differ from Asian Americans without this mutation in terms of blood levels of alcohol and acetaldehyde after ingestion of a moderate amount of alcohol. DESIGN: Double-blind, crossover study. SETTING: Private research institute. PARTICIPANTS: 35 healthy Asian-American men. Three men who became ill after alcohol ingestion and one who had outlying data were excluded. INTERVENTION: Alcoholic beverage, containing 0.56 g of alcohol per kg of body weight, or placebo beverage, containing 3 mL of alcohol, given orally on separate occasions. MEASUREMENTS: Blood levels of alcohol and acetaldehyde measured before and several times after ingestion of the alcoholic or placebo beverage. RESULTS: Participants with ALDH2*2 alleles had significantly higher blood acetaldehyde levels after ingesting alcoholic and placebo beverages than did participants with ALDH2*1 alleles, despite similar blood alcohol concentrations. CONCLUSIONS: Blood acetaldehyde levels rather than blood alcohol concentration may mediate enhanced alcohol sensitivity among Asians with ALDH2*2 alleles. 相似文献
868.
869.
870.
LM Lian YC Chang CC Yang JC Yang KP Kao MY Chung 《Canadian Metallurgical Quarterly》1994,93(8):709-714
A 42-year-old female presented with progressive proximal muscle weakness, generalized hyperreflexia, marked bone pain, severe lumbago and knee arthralgia. Electromyographic study showed short-duration (5-10 msec), variable amplitude (200-2500 microV) polyphasic potentials. A muscle biopsy specimen revealed non-specific type II fiber atrophy. After a comprehensive laboratory work-up, adult Fanconi syndrome was diagnosed. The patient's symptoms, including bone pain and proximal muscle weakness, were relieved after a six-week supplement of tricalcium phosphate, vitamin D3 and sodium bicarbonate. The hyperreflexia also became less brisk. 相似文献