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951.
952.
OBJECTIVE: To determine mortality and factors that might predict outcome in severe community-acquired pneumococcal pneumonia treated by a standard protocol. DESIGN: Prospective, non-concurrent study. SETTING: Respiratory intensive care unit (ICU) in a teaching hospital. PATIENTS: 63 patients who were diagnosed by positive blood culture or Gram stain and culture of sputum or tracheal aspirate were included. MEASUREMENTS AND RESULTS: Clinical features, severity scores including Acute Physiology and Chronic Health Evaluation (APACHE) II, organ failure and lung injury scores, and the clinical course in the ICU were documented; 79% of patients required mechanical ventilation. Bacteraemia was present in 34 patients (54%); there were no distinguishing clinical features between bacteraemic and non-bacteraemic cases. The overall mortality was 21%, with only 5 deaths (15% mortality) in the bacteraemic group. Shock and a very low serum albumin (< 26 g/l) were the only clinical features that differentiated survivors from non-survivors; lung injury, APACHE II and multiple organ failure scores were all predictive of outcome. The positive predictive value and specificity in predicting death in individuals for the modified British Thoracic Society rule 1 were 26 and 64%; APACHE II > 2057 and 88%; > 2 organ failure 64 and 92%; and lung injury > 233 and 73%, respectively. CONCLUSIONS: These results suggest that even in bacteraemic cases mortality should be below 25% with intensive care management and that conventional scoring systems, while predictive of group mortality, are unreliable in individuals.  相似文献   
953.
954.
Avian song learning involves memorizing and reproducing song material produced by conspecifics. In several species song repertoire size correlates with the overall volume of two song-related brain regions, the HVc (acronym used as the proper name) and the robust nucleus of the archistriatum (RA). We raised male zebra finches with two adult tutors and found that individual differences in HVc volume and neuron number correlated positively with differences in the number of tutor syllables accurately copied. These results were replicated in a second study. The relationship between RA volume and song learning was similar, but less robust. Importantly, total repertoire size (number of song syllables) did not correlate significantly with anatomical measures of either the HVc or RA. Because previous work suggests that the volume and neuron number of these regions are not regulated by song learning, it is possible that naturally occurring variation in neuron number constrains how much song material can be copied or reproduced.  相似文献   
955.
The cell-surface receptor tyrosine kinase protein c-erbB-2 is immunocytochemically detected as membrane staining on the surface of cancer cells in 20-30% of cases of breast cancer, and its presence has been associated with poor prognosis for the patient. However, there have been numerous reports of immunocytochemical staining for c-erbB-2 solely in the cytoplasm of some normal and tumour specimens with frequently used anti-sera, and the presence of such staining has been difficult to interpret. It is not known for certain that cytoplasmic c-erbB-2 staining is an artefact of the immunocytochemical procedures used. Thus, mRNA for c-erbB-2 has been quantified in tumours exhibiting only cytoplasmic staining or varying levels of membrane staining using a sensitive, competitive PCR method. Whereas abundant levels of c-erbB-2 mRNA are found in tumours exhibiting membrane staining for c-erbB-2 and these levels correlate with the percentage of tumour cells showing membranous staining for c-erbB-2, the level of c-erbB-2 mRNA in tumours displaying only cytoplasmic staining is no higher than in c-erbB-2-negative specimens.  相似文献   
956.
An emerging hypothesis considers the process of neuronal apoptosis as a consequence of unscheduled and unsynchronized induction of cell cycle mediators. Induction of several cell cycle genes precedes neuronal apoptosis and may be involved in determination of cell fate. We have now characterized changes in expression of cell cycle genes during apoptosis induced by oxidative stress in chick post-mitotic sympathetic neurons. Induction of cyclin B occurred prior to the commitment of neurons to both dopamine- and peroxide-triggered apoptosis. Both the neuronal death and the rise in cyclin B were inhibited by antioxidant treatment, suggesting a functional role for cyclin B induction during neuronal apoptosis. Induction of the cyclin dependent kinase CDK5 protein coincided with the time point when neurons were irreversibly committed to die. Expression of other cell cycle mediators such as cyclin D1 and the cyclin dependent kinases CDC2 and CDK2 was undetected and not induced by exposure to oxidative stress. Comparative analysis of the profile of cell cycle mediators induced during neuronal apoptosis of different neuronal cell populations revealed no distinct pattern of events. There are no cell cycle stage-specific mediators that are ultimately stimulated during neuronal apoptosis, suggesting that multiple pathways of re-activating the dormant cell-cycle, converge to determine entry into apoptosis. Nevertheless, the existence of some cell cycle mediators, that were not reported so far to be induced in post mitotic neurons during oxidative stress, substantiate them as part of the strong differentiating forces.  相似文献   
957.
Congenital anorectal malformations are found in many forms, and are frequently associated with other anomalies, especially of the spinal cord, spine, and urogenital system. Decisions concerning initial management of children with anorectal malformations can be made only after accurate determination of (a) the level and type of malformation, (b) the type of fistula, (c) the developmental state of the sphincter muscle complex, and (d) the presence of associated anomalies. Magnetic resonance imaging has proven to be the only modality to answer all these crucial questions, and has contributed to a better insight in the morphology and pathogenesis of such complex congenital malformations.  相似文献   
958.
959.
OBJECTIVE: The adduction moment at the knee during gait is the primary determinant of medial-to-lateral load distribution. If the adduction moment contributes to progression of osteoarthritis (OA), then patients with advanced medial tibiofemoral OA should have higher adduction moments. The present study was undertaken to investigate the hypothesis that the adduction moment normalized for weight and height is associated with medial tibiofemoral OA disease severity after controlling for age, sex, and pain level, and to examine the correlation of serum hyaluronan (HA) level with disease severity and with the adduction moment in a subset of patients. METHODS: Fifty-four patients with medial tibiofemoral OA underwent gait analysis and radiographic evaluation. Disease severity was assessed using the Kellgren-Lawrence (K-L) grade and medial joint space width. In a subset of 23 patients with available sera, HA was quantified by sandwich enzyme-linked immunosorbent assay. Pearson correlations, a random effects model, and multivariate regression models were used. RESULTS: The adduction moment correlated with the K-L grade in the left and right knees (r = 0.68 and r = 0.60, respectively), and with joint space width in the left and right knees (r = -0.45 and r = -0.47, respectively). The relationship persisted after controlling for age, sex, and severity of pain. The partial correlation between K-L grade and adduction moment was 0.71 in the left knees and 0.61 in the right knees. For every 1.0-unit increase in adduction moment, there was a 0.63-mm decrease in joint space width. In the subset of patients in whom serum HA levels were measured, HA levels correlated with medial joint space width (r = -0.55), but not with the adduction moment. CONCLUSION: There is a significant relationship between the adduction moment and OA disease severity. Serum HA levels correlate with joint space width but not with the adduction moment. Longitudinal studies will be necessary to determine the contribution of the adduction moment, and its contribution in conjunction with metabolic markers, to progression of medial tibiofemoral OA.  相似文献   
960.
Vps4p is an AAA-type ATPase required for efficient transport of biosynthetic and endocytic cargo from an endosome to the lysosome-like vacuole of Saccharomyces cerevisiae. Vps4p mutants that do not bind ATP or are defective in ATP hydrolysis were characterized both in vivo and in vitro. The nucleotide-free or ADP-bound form of Vps4p existed as a dimer, whereas in the ATP-locked state, Vps4p dimers assembled into a decameric complex. This suggests that ATP hydrolysis drives a cycle of association and dissociation of Vps4p dimers/decamers. Nucleotide binding also regulated the association of Vps4p with an endosomal compartment in vivo. This membrane association required the N-terminal coiled-coil motif of Vps4p, but deletion of the coiled-coil domain did not affect ATPase activity or oligomeric assembly of the protein. Membrane association of two previously uncharacterized class E Vps proteins, Vps24p and Vps32p/Snf7p, was also affected by mutations in VPS4. Upon inactivation of a temperature-conditional vps4 mutant, Vps24p and Vps32p/Snf7p rapidly accumulated in a large membrane-bound complex. Immunofluorescence indicated that both proteins function with Vps4p at a common endosomal compartment. Together, the data suggest that the Vps4 ATPase catalyzes the release (uncoating) of an endosomal membrane-associated class E protein complex(es) required for normal morphology and sorting activity of the endosome.  相似文献   
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