Acute acid-base disorders. 2. Specific disturbances

Evaluation of the acid-base status of the body requires measurement of bicarbonate (total carbon dioxide) concentration, pH, and partial pressure of CO2 in arterial blood. Calculation of standard bicarbonate and base excess or deficit is not necessary. The normal concentration of free hydrogen ions (H+) is approximately 40 millimoles/liter, which is equivalent to a pH of 7.4. The normal load of fixed acids is 50 to 80 millimoles in 24 hours. A steady state is maintained by excretion of an equal amount of H+ by the kidneys, which at the same time regenerate bicarbonate to replenish buffer stores. Renal excretion of H+ is in the form of titratable acid and ammonium. Synthesis of ammonia can increase severalfold under the stimulus of acidosis. This is the chief mechanism of long-term compensation. Metabolic acidosis can be due to an excessive acid load (endogenous or exogenous), impaired renal excretion of H+, or bicarbonate loss. Determination of the "anion gap" (unmeasured anions) helps to establish the mechanism of acidosis. Acidosis with a normal anion gap is due to either bicarbonate loss or ingestion of certain chloride salts. A gap larger than normal indicates the presence in the body of acids other than acidfying chloride salts. Management of metabolic acidosis requires accurate diagnosis, clear understanding of the mechansim, and individualized treatment. Metabloic alkalosis is due to loss of H+ (usually from stomach or kidneys) or ingestion of alkali. Measurement of urinary chloride helps establish the mechanism of alkalosis. In saline-responsive alkalosis, the urinary chloride level is very low. This is usually due to gastric loss of H+, and the condition responds to administration of saline solution. When the urinary chloride level is only moderately low, the alkalosis is probably not due to gastric loss of H+. This form of alkalosis (saline-resistant) does not respond well to administration of saline solution and requires use of potassium in treatment. Apprpriate compensatory responses to acidosis or alkalosis are critical to survival. Compensation for metabloic acidosis consists of hyperventilation and enhanced renal excretion of H+, chiefly as ammonium. In metabolic alkalosis, compensation is mainly renal excretion of bicarbonate. Respiratory acidosis is due to alveolar hypoventilation. In chronic situations, a compensatory rise in serum bicarbonate concentration is expected. Management consists of treatment of the cause of hypoventilation. Respiratory alkalosis is due to hyperventilation. Treatment requires identification and correction of the cause of hyperventilation.     

Videogames and young people with developmental disorders.

Young people with developmental disorders experience difficulties with many cognitive and perceptual tasks, and often suffer social impairments. Yet, like typical youth, many appear to enjoy playing videogames. This review considers the appeal of videogames to individuals with autism spectrum disorders, attention deficit hyperactivity disorder, and specific language impairment. It examines how they respond to the various challenges that play entails with particular reference to sensory, cognitive, and social dimensions. It is argued that research into how these young people engage voluntarily with this dynamic and challenging medium offers great potential to extend our empirical and theoretical understanding of the disorders. Many gaps in our current knowledge are identified and several additional themes for possible future research are proposed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Specific acute colonic disorders

This article reviews a variety of specific colonic disorders that may have been an acute clinical presentation. Less common causes of colonic obstruction include volvulus, intussusception, and hernias. Nonobstructive colonic dilatation is most often due to pseudo-obstructions and toxic megacolon. Several miscellaneous disorders discussed include colonic perforation, complications of leukemia that may affect the colon, and pseudomembranous colitis. The pathogenesis and clinical aspects of these disorders are reviewed, but the radiologic features are emphasized.     

Dissociative disorders of the self: A continuum extending into multiple personality.

This article examines the notion that multiple-personality disorder represents the end of a continuum of a defensive dissociation of the self. Three case illustrations are presented in support of this notion. In one case hidden ego states emerged and displayed some behavioral control in the course of hypnotherapy. In another, dissociated part selves were responsible for much of the presenting symptomatology, but did not qualify for a diagnosis of multiple personality. The author argues for the recognition of a continuum of dissociation of the self that extends into multiple-personality disorder. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Sex differences in pervasive developmental disorders

Neonatal size is an important factor in determining the survivorship of infants within the first month of life. Because maternal size has an influence on neonatal size, selection should operate on those characters correlated with birth weight and gestational age, including maternal prepregnancy weight, height, and age. In the present study we use a path-analysis approach to examine the operation of selection on both neonatal and maternal size. We found that neonatal survivorship depends not only on the size of the infant at birth but also on a negative allometric relationship between the size of the neonate and the size of the mother. Thus, although the size of the mother has no direct effect on neonatal mortality, the mothers of surviving infants tend to be smaller relative to the size of their neonate. This may provide a mechanism whereby selection maintains a balance between maternal size and neonate size.     

Nativism versus neuroconstructivism: Rethinking the study of developmental disorders.

This article argues that one dominant position in psychology, linguistics, neuroscience, and philosophy about how genetic disorders point to the innate specification of dissociated modules in the human brain should be replaced by a dynamic, neuroconstructivist approach in which genes, brain, cognition, and environment interact multidirectionally. The article challenges current thinking about a series of questions: (a) Do significantly better scores in one domain necessarily indicate an intact module? (b) What do scores in the normal range suggest? (c) What is wrong with mental-age matching? (d) Why is the notion of an intact module unlikely? (e) Do developmental disorders suggest associations rather than dissociations? (f) Is the environment the same for atypically developing individuals? The article concludes by examining the implications of taking a neuroconstructivist approach and by arguing that human intelligence is not a state (i.e., not a collection of static, built-in modules that can be intact or impaired) but a process (i.e., the emergent property over developmental time of dynamic, multidirectional interactions between genes, brain, cognition, behavior, and environment) with domain-specific outcomes impossible without the process of development. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Pervasive developmental disorders: neurological perspectives]

The pervasive disorders of development (TPD) or disorders within the spectrum of autism (TEA) are two terms which are often used to describe a well-defined group of behaviour disorders characterized by changes in social interaction and language communication together with repetitive behaviour patterns. This group of disorders has multiple etiologies and the clinical manifestations vary in severity. In this study the incidence of a selected group of neurological changes and neurodiagnostic tests in 421 children with TDP is analyzed. 11% of the children had genetic disorders such as chromosomial disorders, genetic syndromes and family incidence. 18% of the children had motor disorders with hypotonicity being the commonest (85%). 71% of the children were stereotyped. 59% of the children had cogniscitive functions which were appropriate, or nearly so, for their chronological age, 28% of the children had language regression. 13% had epileptic crises. The electroencephalogram and cerebral magnetic resonance were abnormal in 29% and 19% respectively of the children on whom these tests were done.     

基于Web的语言实验室管理系统任课教师子系统的设计及操作

基于Web的语言实验室管理系统是结合了外语教学实践和语言实验室管理模式研发的一套管理便捷、功能完善、安全性高的网络实验室管理系统。其中任课教师管理子系统由任课教师使用,与实验室管理员共同参与语言实验室的日常管理。本文详细介绍了任课教师管理子系统的设计结构及操作。     

Lead intoxication in children with pervasive developmental disorders

Ten clinical isolated strains of Human cytomegalovirus (HCMV) were obtained from 73 urine specimens of different people. Isolations from urine were carried out in human embryolung fibroblasts. Viral isolates were passaged four times. HCMV DNAs of laboratory strain AD169 and 10 clinical isolated strains were extracted with Hirt method, digested with each of the restriction enzymes EcoRI, Hind II. Comparison of restriction fragment length polymorphism (RFLP) of AD169 and isolated strains were made by hybridizing digested DNA with 32P labeled with HCMV Hind II cloned subgenomic fragments as the probe (pCM1035, pCM1015). pCM1035 is located in the joining region between the long(L) and short (S) unique sequences of the virus (L-S junction) pCM1015 is located in the terminal sequences of the virus. The results showed the genomic high degree of homology existed among all strains and the variable restriction site was in the L-S junction and terminal portion. The RFLP patterns of the clinical isolates which did not have relation in epidemiology were different, but the patterns of clinical isolates related in epidemiology were quite similar. Polymorphism frequently occurred in this case of EcoRI digested fragment hybridized with the probe of pCM1035. Southern hybridization of HCMV isolations is useful to researches into the molecular epidemiology and pathogenesis of HCMV infection.     

Genetic counseling in autism and pervasive developmental disorders

Although alcohol intake and hepatitis B and C virus (HBV and HCV) infections are the major determinants of liver cirrhosis (LC) in western countries, the joint effect of these factors on LC risk has not yet been adequately studied. Data from three case-control studies performed in Italy were used. Cases were 462 cirrhotic patients admitted to Hospitals for liver decompensation. Controls were 651 inpatients admitted for acute diseases unrelated to alcohol. Alcohol consumption was expressed as lifetime daily alcohol intake (LDAI). Three approaches were used to explore the interaction structure. The Breslow and Storer parametric family of relative risk functions showed that an intermediate structure of interaction from additive to multiplicative was the most adequate one. The Rothman synergism index showed that the interaction structure between LDAI and viral status differed significantly from the additive model in particular for high levels of alcohol intake. When multiple regression additive and multiplicative models were compared after adjustment for the known confounding variables. a trend of the interaction structure towards the multiplicative model was observed at increasing levels of consumption. Better methods are needed for assessing mixed interaction structures in conditions characterized by multifactorial etiologies like cirrhosis of the liver.     

Psychopathology in children and adolescents with developmental disorders

Children and adolescents with developmental disorders suffer from a wide range of psychopathology. However, there are no published studies examining this subject exclusively in this population using recent diagnostic criteria. The primary purpose of this paper is to report on the diagnosis encountered in a clinical setting using DSM-III-R. The medical records of all individuals assessed in a specialized program during a 1-year period were reviewed looking at their demographic features, diagnoses, and target behaviors. Our sample consisted of 233 subjects and contained significantly more boys than girls. The most common psychiatric diagnoses were oppositional defiant disorder and attention deficit hyperactivity disorder. Pica, organic mental disorder NOS, and Autistic Disorder were more often encountered in individuals with low intellectual functioning. Depressive disorders, posttraumatic stress disorder, and developmental speech/language disorders were diagnosed more in high functioning subjects. The most common symptom was impulsivity. This retrospective study highlights the need for more rigorous examination of current diagnostic concepts and criteria in children and adolescents with developmental disorders. Prospective studies should be conducted with standardized instruments in clinics and community samples to provide more information on psychiatric disorders in this population.     

Hemispheric function in developmental language disorders and high-level autism

Two groups of children with contrasting types of developmental language disorder (phonologic-syntactic and semantic-pragmatic) were compared with a group of children with high-level autism and with a control group of normal children on a broad battery of neuropsychological tests, known to be sensitive to left-right hemisphere damage. Significant differences found between the groups suggest contrasting forms of hemispheric dysfunction.     

The genetic aspects of developmental dyslexia.

Discusses evidence concerning genetic influences on developmental dyslexia, a disorder characterized by difficulty in learning to read despite adequate opportunity and intelligence. Research on familial incidence, concordance in twins, the influence of parental age at the child's birth, and the subtyping of dyslexics is summarized. It is concluded that there is strong evidence for the heritability of a subtype based on verbal/language deficiency, perhaps reflecting reversed cerebral asymmetry, for which a genetic marker has been found. It is uncertain whether this subtype is caused by left hemispheric impairment or immaturity. There is somewhat weaker evidence for the heritability of a subtype based on visual/spatial deficiencies and a mixed subtype. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The developmental basis of evolutionary change.

It is a hard-won insight that developmental change is essential to evolution, and the issue has received little consideration in the psychological literature. The origin of the concept can be traced to the nineteenth century biologist St. George Mivart, with the more systematic and extensive treatments of the issue in the early twentieth century by Walter Garstang, Gavin de Beer, and Richard Goldschmidt playing an instrumental role in fleshing out the idea and keeping it alive. Garstang and de Beer held that genetic change, either through selective breeding or mutation, could change the timing of ontogenetic events in various defined ways to give rise to a new species. Goldschmidt felt that a developmental macromutation was necessary to produce a genuine evolutionary novelty. In the view of Garstang, de Beer, and Goldschmidt, a genetic change or mutation is necessary to bring about the developmental changes that lead to evolution. In the present article I utilize the developmental change concept in a different manner than the aforementioned writers. In essence, I describe a different evolutionary pathway, one in which developmental changes in behavior lead to evolutionary change. On this view, genetic change is a secondary or tertiary consequence of enduring behavioral changes brought about by nongenetic alterations of species-typical development. (PsycINFO Database Record (c) 2010 APA, all rights reserved)