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11.
We report a case of malakoplakia in association with colonic adenocarcinoma. Tumour-associated malakoplakia in the gastrointestinal tract is a rare finding, generally confined to the colon. It may be locally aggressive, with invasion of pericolic tissues, but is always located adjacent to the tumour. This contrasts with the often more diffuse, multifocal distribution of colonic malakoplakia in association with other pathologies. 相似文献
12.
Smoking and raven IQ 总被引:1,自引:0,他引:1
Nicotine has recently been shown to enhance measures of information processing speed including the decision time (DT) component of simple and choice reaction time and the string length measure of evoked potential waveform complexity. Both (DT and string length) have been previously demonstrated to correlate with performance on standard intelligence tests (IQ). We therefore hypothesised that nicotine is acting to improve intellectual performance on the elementary information processing correlates of IQ. In the current experiment we tested this hypothesis using the Raven Advanced Progressive Matrices (APM) test. APM scores were significantly higher in the smoking session compared to the non-smoking session, suggesting that nicotine acts to enhance physiological processes underlying performance on intellectual tasks. 相似文献
13.
A total of 580 breast milk samples were collected from 56 lactating women living in a rural village community in The Gambia, West Africa, and 92 samples were obtained from 57 lactating women living in Cambridge, England. Total zinc content of each sample was measured by atomic absorption spectrometry, and pooled samples of the Gambian breast milks, representing successive periods of lactation, were fractionated into fat, whey and insoluble casein fractions, to examine zinc distribution. The two sets of milks both exhibited a dramatic decline in total zinc concentrations with increasing duration of lactation, in common with previous studies. However, the UK milks unexpectedly had lower zinc contents at all stages than the Gambian milks. Milk zinc levels were not significantly related to either maternal age or parity in the Gambian women. The proportion of zinc found in the sedimentable fraction remained nearly constant with increasing duration of lactation, but the proportion found in the fat fraction increased and the proportion in the whey fraction declined. These observations are potentially relevant for estimations of milk zinc availability and the fulfillment of zinc requirements by infants, and hence for infant feeding practices. 相似文献
14.
Dolores Acevedo-Garcia Lisa M. Bates Theresa L. Osypuk Nancy McArdle 《Social science & medicine (1982)》2010
Global self-rated health (SRH) is increasingly a key indicator in the assessment of immigrant health. However, evidence of the impact on SRH of generational status, duration of residence in the US, and socioeconomic status (SES) among immigrants and their offspring is limited and inconsistent. We overcome limitations in existing research on this topic by using a uniquely large and diverse data source, the March Annual Social and Economic Supplement of the Current Population Survey (CPS; 2003–2007) (n = 637,209). As a result, we are able to disaggregate results by race/ethnicity, account for country of origin, and consider the role of multiple dimensions of SES. We find that overall first-generation immigrants in the US have lower odds of poor/fair SRH compared to the third-generation. This association is particularly strong for blacks and Hispanics but not significant for Asians. Among first-generation Asians and Hispanics, longer duration of residence is positively associated with poor/fair SRH. Finally, socioeconomic gradients in SRH tend to be less pronounced among the first-generation (versus the third) and, within the first-generation, among recent arrivals (versus those with longer durations). Our results highlight the importance of explicitly accounting for multiple immigration-related variables and their interactions with race/ethnicity and SES. Otherwise, studies may misestimate SRH differences by race/ethnicity and socioeconomic status. The continued growth of the US immigrant population and the second-generation underscore the need to examine patterns in immigrant health systematically. 相似文献
15.
16.
E Bates 《Annals of internal medicine》1991,114(8):701-702
17.
We report a novel double wire technique for ipsilateral access of the external iliac/common femoral artery transition side-branches in a patient with active extravasation. The case is noteworthy in that asymptomatic extravasation was noted in both the inferior epigastric and deep circumflex iliac branches on femoral angiography prior to intraaortic balloon pump insertion following emergent diagnostic left heart cathetrization. We speculate the side branch injury was related to the J-wire and describe how this complication may be best treated by the ipsilateral technique reported herein. 相似文献
18.
M E Bates 《Journal of studies on alcohol》1989,50(2):143-154
The focus of this study was the effect of repeated episodes of alcohol intoxication on two processes involved in visual movement discrimination: visual sensitivity and decision-making. Four female subjects were asked to discriminate between a stationary light signal and one that changed position in the center of a dark visual field. Prior to each of 15 alcohol testing sessions, a dose of .66 ml of 95% USP ethanol per kg body weight was administered to each subject and BAL was sampled frequently within sessions. Differences in subjects' pre- and postalcohol performance were evaluated within the framework of a psychophysical model that mathematically characterizes the problem of movement discrimination and yields independent estimates of visual sensitivity and decisional aspects of subjects' performance. Evidence for specificity in the development of sensory versus decisional process tolerance to intoxication effects was found. The major result was that each subject made large and statistically reliable shifts in decisional criteria during the time course of the blood alcohol curve within alcohol testing sessions, even when visual sensitivity had adapted to alcohol intake effects. The results of this study illustrate the utility of tracing acute intake effects over repeated occasions of intoxication, and empirically testing subjects' assumed decisional strategies when modeling these effects. 相似文献
19.
The renal dopamine receptors. 总被引:1,自引:0,他引:1
P A Jose J R Raymond M D Bates A Aperia R A Felder R M Carey 《Journal of the American Society of Nephrology : JASN》1992,2(8):1265-1278
Dopamine is an endogenous catecholamine that modulates many functions including behavior, movement, nerve conduction, hormone synthesis and release, blood pressure, and ion fluxes. Dopamine receptors in the brain have been classically divided into D1 and D2 subtypes, based on pharmacological data. However, molecular biology techniques have identified many more dopamine receptor subtypes. Several of the receptors cloned from the brain correspond to the classically described D1 and D2 receptors. Several D1 receptor subtypes have been cloned (D1A, D1B, and D5) and are each coupled to the stimulation of adenylyl cyclase. The D2 receptor has two isoforms, a shorter form, composed of 415 amino acids, is termed the D2short receptor. The long form, called the D2long receptor, is composed of 444 amino acids; both are coupled to the inhibition of adenylyl cyclase. The D3 and D4 receptors are closely related to, but clearly distinct from, the D2 receptor. They have not yet been linked to adenylyl cyclase activity. Outside of the central nervous system, the peripheral dopamine receptors have been classified into the DA1 and DA2 subtypes, on the basis of synaptic localization. The pharmacological properties of DA1 receptors roughly approximate those of D1 and D5 receptors, whereas those of DA2 receptors approximate those of D2 receptors. A renal dopamine receptor with some pharmacological features of the D2 receptor but not linked to adenylyl cyclase has been described in the renal cortex and inner medulla. In the inner medulla, this D2-like receptor, termed DA2k, is linked to stimulation of prostaglandin E2 production, apparently due to stimulation of phospholipase A2. Of the cloned dopamine receptors, only the mRNA of the D3 receptor has been reported in the kidney. The DA1 receptor in the kidney is associated with renal vasodilation and an increase in electrolyte excretion. The DA1-related vasodilation and inhibition of electrolyte transport is mediated by cAMP. The role of renal DA2 receptors remains to be clarified. Although DA1 and DA2 receptors may act in concert to decrease transport in the renal proximal convoluted tubule, the overall function of DA2 receptors may be actually the opposite of those noted for DA1 receptors. Dopamine has been postulated to act as an intrarenal natriuretic hormone. Moreover, an aberrant renal dopaminergic system may play a role in the pathogenesis of some forms of hypertension. A decreased renal production of dopamine and/or a defective transduction of the dopamine signal is/are present in some animal models of experimental hypertension as well as in some forms of human essential hypertension. 相似文献
20.
The purposes of the study were: (1) to evaluate the effects of different surfaces on the relationship between subtalar and knee joint function, and (2) to examine/explore alternative approaches to the evaluation of these relationships. Five subjects ran under four different surface conditions of various hardness, while both rear and sagittal view kinematic data were collected (200 Hz). Critical parameters describing the knee angle and rearfoot motion were examined in conjunction with a curve analysis technique which incorporated slope differences and curve correlations. A repeated measure ANOVA design (surface × subject) was used along with single subject procedures. The results of the study support a strong inter-relationship between pronation and knee joint function via tibial rotation and underlined it as a possible mechanism for injury. Moreover, discrete point analysis might not be the most appropriate methodology for evaluating dynamic functions such as rearfoot motion and knee angle. Extreme methodological care must be exercised when evaluating these functions to avoid oversmoothing and/or masking correlations and differences due to differential subject responses and individual variability. The fact that increased impact force facilitated timing discrepancies between subtalar and knee joint function resulting in a transition of the pronation curve from a unimodal to bimodal configuration, is hypothesized as a possible explanation to better understand the inter-relationships among these lower extremity functions and their relationship to running injuries. 相似文献