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991.
992.
AS Agabalian AP Makarian AM Agavelian AS Akopian 《Canadian Metallurgical Quarterly》1998,319(10):16-18
Activities of some enzymes and content of medium-weight molecules in patients with colorectal cancer were studied in order to assess the diagnostic value of these parameters for detection of tumors in the large intestine and development of endogenous intoxication after surgery and for prediction of remote results of treatment. Increased activities of creatine phosphokinase and hexokinase is typical of tumor growth, whereas increased activities of alkaline phosphatase and gamma-glutamyl transpeptidase are observed only in metastases to the liver. The role of medium-weight molecules in the diagnosis of endogenous intoxication during the early postoperative period is shown. The content of these molecules in the sera increases 3 days before clinical manifestation of endotoxicosis, when the traditional parameters are virtually normal. 相似文献
993.
The immune response of chickens to 11 isolates of LaSota strain Newcastle disease virus (NDV) and to 7 isolates of B1 strain NDV was studied in specific-pathogen-free chickens. Most of the vaccine strains were from commercial vaccine producers. Comparison of immunogenicity were made of these vaccines; five other lentogenic NDV strains, not used commercially, were also evaluated. From the criteria of hemagglutination inhibition (HI) and virus serum (VN) neutralizing titers, differences were observed with certain isolates within the LaSota and B1 vaccine groups. Whereas the majority of vaccine strains fell within a predictable range, some proved considerably less in their ability to engender expected titers. Two-to threefold differences in titers were observed with some of the strains compared. Two cloned LaSota NDV strains did not compare favorably, or with expected higher titers, with uncloned or conventional LaSota strain virus isolates. Similarly, certain B1 and LaSota strains passaged in chickens did not demonstrate a greater immunogenic potential over conventional, commercial vaccines of similar strain designation but not passaged in chickens. Whereas none of the NDV strains demonstrated evidence of neurotropism or lethality, postvaccination respiratory reactions were difficult, if not impossible, to evaluate in laboratory isolation units. The complexity of selecting ND vaccines for field use is discussed briefly. 相似文献
994.
MA Ostrowski DC Krakauer Y Li SJ Justement G Learn LA Ehler SK Stanley M Nowak AS Fauci 《Canadian Metallurgical Quarterly》1998,72(10):7772-7784
Virus replication in a human immunodeficiency virus (HIV)-infected individual, as determined by the steady-state level of plasma viremia, reflects a complex balance of viral and host factors. We have previously demonstrated that immunization of HIV-infected individuals with the common recall antigen, tetanus toxoid, disrupts this steady state, resulting in transient bursts of plasma viremia after immunization. The present study defines the viral genetic basis for the transient bursts in viremia after immune activation. Tetanus immunization was associated with dramatic and generally reversible shifts in the composition of plasma viral quasispecies. The viral bursts in most cases reflected a nonspecific increase in viral replication secondary to an expanded pool of susceptible CD4(+) T cells. An exception to this was in a patient who harbored viruses of differing tropisms (syncytium inducing and non-syncytium inducing [NSI]). In this situation, immunization appeared to select for the replication of NSI viruses. In one of three patients, the data suggested that immune activation resulted in the appearance in plasma of virus induced from latently infected cells. These findings illustrate certain mechanisms whereby antigenic stimulation may influence the dynamics of HIV replication, including the relative expression of different viral variants. 相似文献
995.
AS Lillard 《Canadian Metallurgical Quarterly》1998,69(4):981-93; discussion 994-5
How children understand the mental state of pretense has recently become an active area of inquiry, with some research suggesting that young children do not understand that pretending is based on mentally representing some alternate state of affairs. Because intention is thought to be understood earlier than mental representation generally, these experiments tested whether children understand pretense intentions at an earlier age than they understand pretense mental representations. Children were told about a character's intentions and conflicting actions, and were asked about the character's pretense. Across 5 experiments, children did not demonstrate appreciation that intention is crucial to pretense. Various methodological factors that might have compromised the results were examined, but to no effect. 相似文献
996.
BACKGROUND: Involuntary detrusor contractions often cause irritative symptoms such as urgency and incontinence. A dog model for acutely induced variable bladder outlet resistance was developed to investigate the possible role of prostatic afferent nerve fibers in the development and maintenance of detrusor instability. METHODS: Fifty-eight mongrel dogs (weight range 19.5-36.5 kg) were divided into five groups: group I (n = 11) had surgically induced bladder outlet obstruction. Group II (n = 14) had urinary obstruction and bilateral sectioning of the lowest branches of the pelvic plexus supplying the prostate. Group III (n = 10) had prostate denervation only. Groups IV (n = 10) and V (n = 13) were sham-operated and controls, respectively. In the obstructed groups (I and II), an artificial urinary sphincter (length 4.5-6.0 cm) was placed around the bladder neck and connected to a reservoir placed subcutaneously to allow postoperative adjustments of urinary resistance. All dogs were evaluated at baseline and postoperatively at 1, 3, and 6 months with uroflowmetry, postvoid residual urine volume, cystometry as well as serum creatinine, and urinalysis. RESULTS: Occurrences of detrusor instability were not associated with prostatic denervation input. The mean peak flow rates decreased significantly in the obstructed groups at all follow-ups, but did not change significantly in the nonobstructed groups. Postoperatively, the mean maximum bladder capacity was significantly decreased for groups I and II only. However, a significant correlation between maximum bladder capacity and maximum detrusor pressure could not be detected at any time point in any of the groups. Mean postvoid residual urine volume varied considerably in all groups over time. Creation of a urinary model of infravesical obstruction was associated with considerable problems. CONCLUSIONS: In our dog model of bladder outlet obstruction, prostatic sensory nerve fibers appear not to be involved in detrusor instability. Surgical induction of a constant model of bladder outlet obstruction was difficult even in a large animal. The observations from the present study raise questions about the validity of obstructive urinary animal models. 相似文献
997.
Thrombolytic therapy (TT) was performed in 39 of 81 patients with unstable angina pectoris (UAP) resistant to conventional treatment. TT was found to improve prognosis of UAP, to quicken UAP stabilization. Predictors of UAP unfavorable course were discovered. TT is indicated in patients suffering from resistant UAP with markers of poor prognosis. 相似文献
998.
Y Guan RC Manuel AS Arvai SS Parikh CD Mol JH Miller S Lloyd JA Tainer 《Canadian Metallurgical Quarterly》1998,5(12):1058-1064
The DNA glycosylase MutY, which is a member of the Helix-hairpin-Helix (HhH) DNA glycosylase superfamily, excises adenine from mispairs with 8-oxoguanine and guanine. High-resolution crystal structures of the MutY catalytic core (cMutY), the complex with bound adenine, and designed mutants reveal the basis for adenine specificity and glycosyl bond cleavage chemistry. The two cMutY helical domains form a positively-charged groove with the adenine-specific pocket at their interface. The Watson-Crick hydrogen bond partners of the bound adenine are substituted by protein atoms, confirming a nucleotide flipping mechanism, and supporting a specific DNA binding orientation by MutY and structurally related DNA glycosylases. 相似文献
999.
BI Cohen MK Pagnillo I Newman BL Musikant AS Deutsch 《Canadian Metallurgical Quarterly》1998,79(5):520-525
BACKGROUND: Although the use of extracorporeal life support (ECLS) following repair of congenital heart defects in children is increasing, the criteria for ECLS usage in these patients is not well defined. The overall survival of such patients is disappointingly low and may depend on both the indication for support and the time at which ECLS is commenced. METHODS: Between January 1993 and December 1996, 727 children underwent surgery for congenital heart defects at our institution with an overall hospital mortality of 5.8% (42 children). Nine of these children were treated with ECLS postoperatively. There were seven males and two females with a mean age of 7.2 months (range 2 weeks-3 years). Seven children could not be weaned from cardiopulmonary bypass (CPB) in the operating theatre. A further two were treated with ECLS later on during the postoperative period (commenced at 14 and 48 h). Full veno-arterial extra corporeal membrane oxygenation (ECMO) support was used in all children except one in whom a left ventricular assist device (LVAD) was used. RESULTS: The median duration of support was 121 h (range 15-648 h). Four children (44%) were weaned from support and two of these are long-term survivors. Of the seven children in whom ECLS was instituted because of failure to wean from CPB, there was one long term survivor (LVAD support). Of the two patients in whom ECLS was instituted during the post-operative period there is one long-term survivor. CONCLUSIONS: Weaning form ECLS and decannulation in 44% of our patients is comparable to other series of post-cardiotomy patients requiring ECLS. However, full veno-arterial ECMO instituted because of a failure to wean from CPB during corrective surgery is associated with an extremely poor outcome (zero long-term survivors in six patients). 相似文献
1000.
The mitogen-activated protein kinase (MAPK) signal transduction pathway plays an essential role in cell cycle progression and can be activated by many growth factor/mitogen pathways including estrogen. MAPK has also been implicated in ligand-independent activation of estrogen receptor-alpha (ER-alpha). The development of estrogen-independent growth in breast cancer is likely a first step in progression to hormone independence and antiestrogen resistance. We examined MAPK expression and activity in T5-PRF and T5 human breast cancer cells. T5-PRF is an estrogen-nonresponsive cell line developed from T5 cells by chronically depleting the cells of estrogen in long-term culture. MAPK activity measured in vitro was significantly higher (P < 0.05) in T5-PRF compared with T5 cells. Western blot analyses showed increased levels of active dually phosphorylated MAPK in T5-PRF cell extracts compared with T5. The increased activity and expression of MAPK may contribute to the estrogen nonresponsive growth phenotype and ligand-independent activity of ER in T5-PRF cells. 相似文献