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81.
In three patients with infantile hemiplegia syndrome, MR imaging done later in life showed significant volume loss in the cerebellar hemisphere contralateral to the side of the affected cerebrum in two and ipsilateral in one. By comparison, the cerebellar volume loss seemed to correlate with the degree of volume loss in the contralateral cerebral hemispheres in two patients. These observations provide morphological evidence of the phenomenon of crossed and uncrossed/ipsilateral cerebral cerebellar diaschisis (CCD and ICD). Functional neuroimaging studies in support of the concept of CCD and ICD have been critically reviewed in the light of the morphological changes demonstrated in the cases cited herein.  相似文献   
82.
Attention has been devoted over the past two decades to the identification of temperamental risk factors for child psychopathology. These qualities, evident in toddlerhood or earlier, have the advantage of being measurable in standardized laboratory observations well before children reach the age of onset or diagnosis of psychiatric disorders. Our group's programmatic research over the past 15 years, and that of others, has provided evidence linking "behavioral inhibition to the unfamiliar" in toddlerhood or early childhood with later social anxiety disorder. In addition, recent results by our group have suggested that "behavioral disinhibition" in early childhood, measured by the same laboratory methods, may be linked with later disruptive behavior and comorbid mood disorders. In this article, we discuss our approach to the study of temperamental precursors to disorders in high-risk children, summarize the literature linking behavioral inhibition and disinhibition to later psychopathology, and suggest directions to take in applying this methodology to the search for temperamental precursors to pediatric bipolar disorder.  相似文献   
83.
MRI, done later in life, in two patients with infantile hemiplegia syndrome showed significant volume loss in the cerebellar hemisphere contralateral to the side of the affected cerebrum. The cerebellar volume loss seemed to correlate with the degree of volume loss in the contralateral cerebral hemisphere. These observations provide morphological evidence of the phenomenon of crossed cerebral-cerebellar diaschisis (CCD). Functional neuroimaging studies in support of the concept of CCD has been critically reviewed.  相似文献   
84.
Long House Valley in the Black Mesa area of northeastern Arizona (U.S.) was inhabited by the Kayenta Anasazi from about 1800 before Christ to about anno Domini 1300. These people were prehistoric ancestors of the modern Pueblo cultures of the Colorado Plateau. Paleoenvironmental research based on alluvial geomorphology, palynology, and dendroclimatology permits accurate quantitative reconstruction of annual fluctuations in potential agricultural production (kg of maize per hectare). The archaeological record of Anasazi farming groups from anno Domini 200-1300 provides information on a millennium of sociocultural stasis, variability, change, and adaptation. We report on a multiagent computational model of this society that closely reproduces the main features of its actual history, including population ebb and flow, changing spatial settlement patterns, and eventual rapid decline. The agents in the model are monoagriculturalists, who decide both where to situate their fields as well as the location of their settlements. Nutritional needs constrain fertility. Agent heterogeneity, difficult to model mathematically, is demonstrated to be crucial to the high fidelity of the model.  相似文献   
85.
Pheromonal mediation of reproductive function proceeds along a neuroanatomical pathway that connects the vomeronasal organ (VNO) at the periphery with downstream target-sites in the amygdala and hypothalamus. The MAPK pathway is a prominent cascade linking receptor activation to induction of effectors such as c-Fos. We addressed the question: Does a specific pheromone stimulus lead to activation (phosphorylation, P) of MAPK in the VN system of the male mouse? Phosphorylation of MAPK in the VN system was evaluated 15-30 min and 1.5-2 h after exposure to female odors, using immunocytochemical techniques. A rapid and transient cytoplasmic expression of PMAPK was noted in the VNO with a unique distribution of the expressing neurons in columns extending over the entire basal to apical axis. A rapid and sustained expression was noted in most amygdaloid and hypothalamic VN target-sites and also in a few amygdaloid and hypothalamic sites outside the traditional VN system. The extent of expression and the subcellular compartmentalization (nucleus, cytoplasm, processes) of PMAPK were region-dependent. Of the VN target-sites, the accessory olfactory bulb (AOB) stood out in the lack of expression of PMAPK, in the high expression of the MAPK enzyme itself and in the massive of expression of c-Fos. This expression profile implicates another pathway(s) in mediating VNO signaling to the AOB. Our results are the first to demonstrate the use of PMAPK to trace functional pathways. Based on the wide cellular and intracellular expression of phosphorylated MAPK in the VN system, we propose that the MAPK pathway plays an important role in mediating female pheromone signaling in the male mouse.  相似文献   
86.
Dental clinicians and other health care providers have long been concerned about a variety of infectious agents that may be transmitted within the dental setting. Many infectious diseases, including human immunodeficiency virus, hepatitis, tuberculosis, and syphilis are important both because of their potential transmissibility and because the first manifestations of the disease may appear in the oral cavity. Oral disease as a consequence of primary syphilis is rare. This article details a patient presenting with a labial nodule as her only clinical manifestation of undiagnosed primary syphilis.  相似文献   
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We have obtained two Allium cepa extracts (C1 and C2) which were characterized from chemical and microbiological point of view. The C1 extract is the richest concerning the content in flavonoids, triterpenic acids, amino acids, compounds recognized for their beneficial effects in wound healing. All this data shows us the possibility of using the Allium cepa extracts in the treatment of wounds, scars. As well, the antimicrobial activity of the two extracts was evaluated. The C2 extract was efficient as antimicrobial agent, but there are necessary special preserving conditions.  相似文献   
90.
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