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1.
Rhesus monkeys maintained in individual cages are rarely inactive when observed by humans unfamiliar to them. It has been observed that these animals display a greatly reduced behavioral repertoire after they are transferred to primate chairs. The present study used systemic behavioral observations to document those changes and to examine additional changes produced by arm restraint. Chair restraint was associated with a reduction in activity which was intensified when animals were further immobilized by arm restraint. This immobilization produced a reduction of tone in all limbs, a reduction of spontaneous behavior, and the appearance of eye closure. Electroencephalographic (EEG) correlates of the behavioral changes were examined also, using quantitative data generated through power spectral analysis of sensorimotor cortical EEG signals. Immobilization was accompanied by a significant increase in spectral density at 12 to 15 Hz which was most marked at mid and far lateral rholandic recording sites. No other significant changes were seen in the frequency bands studied. When the immobilized animal was alerted with novel stimuli, lower frequencies were attenuated but 12- to 15-Hz activity remained enhanced. These findings indicate that a unique immobilization response is elicited by restraint in the rhesus monkey which is associated with discrete changes in both behavior and accompanying EEG patterns. 相似文献
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Jason A. Zell Archana J. McEligot Argyrios Ziogas Randall F. Holcombe ∗ Hoda Anton-Culver ∗ 《Nutrition and cancer》2013,65(1):36-45
Potentially favorable effects of wine consumption on colorectal cancer (CRC) incidence have been reported, but effects on clinical outcomes are unknown. This case-only analysis was designed to investigate outcomes among familial (n = 141) and sporadic (n = 358) CRC patients enrolled in the University of California Irvine CRC gene-environment study during 1994–1996 based on their reported frequency of wine consumption in the year prior to diagnosis. Cases were categorized as either regular or infrequent wine consumers. Univariate survival rate analyses were estimated using the Kaplan and Meier method and log-rank test. Multivariate survival analyses were performed using Cox proportionalhazards ratios (HRs). Earlier stage at presentation (P = 0.034) was noted for familial (but not sporadic) CRC cases reporting regular wine consumption. An overall survival (OS) benefit was observed for familial (but not sporadic) CRC cases that were regular (10-yr OS = 75%) versus infrequent wine consumers (10-yr OS = 47%; P = 0.002). This survival improvement for familial CRC cases remained after adjustment for age, stage, treatment, and other clinically relevant factors (HR = 0.50, 95% confidence interval = 0.25–0.99). Our findings implicate favorable effects of wine consumption on stage at presentation and survival in CRC, selectively among familial CRC cases. 相似文献
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MA Kemp A Mitra T Mendes da Costa RF Spencer 《Annals of the Royal College of Surgeons of England》2013,95(4):266-270
Introduction
Soft tissue reactions following metal-on-metal (MoM) arthroplasty of the hip have been under considerable discussion. These reactions are seen following both hip resurfacing and MoM total hip arthroplasty (THA). The phenomenon may arise owing to shedding of metal particles in high wear states, hypersensitivity with normal metal wear rates or a combination of the two.Methods
Three patients were identified who had developed a soft tissue reaction (pseudotumour) following MoM hip resurfacing procedures. The prostheses were revised to ceramic-on-ceramic (CoC) THA with only minimal debridement of the pseudotumour. Pre and postoperative magnetic resonance imaging was performed to assess the size of the lesions.Results
Progressive and satisfactory resolution of the associated pseudotumours was identified following revision of the prostheses to CoC THA.Conclusions
In the early stages of pseudotumour formation following MoM hip resurfacing, this potentially devastating condition can be managed adequately with revision to a CoC bearing THA with minimal soft tissue excision. 相似文献4.
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We have identified a black individual with homozygous sickle cell anemia who is the silent carrier of alpha-thalassemia (genotype - alpha/alpha alpha) due to heterozygosity for the leftward deletion alpha-thal-2 haplotype. This deletion has not been described previously in a black subject and is the only leftward deletion that we have found among 255 alpha-thal-2 chromosomes from sickle cell subjects. Its effects on the clinical, hematologic, biosynthetic, and cellular pathology of sickle cell anemia resemble those reported for the common alpha-thalassemia genotypes of the black population. 相似文献
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Follicle lysis is a characteristic alteration of B cell follicles described recently in lymph node biopsies from homosexual men. It consists of disruption of germinal centers by aggregates of small mature lymphocytes variably associated with erythrocyte extravasation. We studied the immunohistology of follicle lysis identified in lymph node biopsies from 11 homosexual men. The results indicate that follicle lysis has two principal immunohistologic features: (1) intrafollicular aggregates of small lymphocytes predominantly of polytypic mantle B cell phenotype (T015+/Leu-8+/mu+/delta+/k+ or lambda+), and (2) disruption of the normal, unified follicular meshwork of R4/23+ dendritic reticulum cells by these B cell aggregates. These structural alterations may affect the functional integrity of the germinal center as it pertains to the abnormal B cell effector function and the increased prevalence of B cell lymphoma recently documented in the acquired immunodeficiency syndrome and related disorders. Because dendritic reticulum cells weakly express the Leu-3 (T4) antigen, which is known to be an essential component of the receptor for human T- lymphotropic virus type III/lymphadenopathy-associated virus (HTLV- III/LAV) retrovirus infection, it is possible that retroviral infection of dendritic reticulum cells may play a role in the pathogenesis of follicle lysis. 相似文献
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