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1.
M Peleg  Z Heyman  L Ardekian  S Taicher 《Canadian Metallurgical Quarterly》1998,56(10):1129-31; discussion 1132
PURPOSE: This study examined the value of ultrasonography as a diagnostic tool in the treatment of superficial acute odontogenic fascial space infections. PATIENTS AND METHODS: The study group consisted of 50 patients in whom both radiographic and sonographic examinations, as well as a needle aspiration, were performed. RESULTS: Purulent fluid was aspirated in 22 of the 50 patients. Six patients diagnosed as suffering from cellulitis had a repeated ultrasonography scan. In four, abscess formation was diagnosed on the third day. CONCLUSIONS: Ultrasonography is an effective diagnostic tool to confirm abscess formation in the superficial fascial spaces and is highly predictable in detecting the stage of infection.  相似文献   

2.
Endurance training leads to an increase in the content of individual mitochondrial hemeproteins in skeletal muscle. To deduce the control mechanisms involved, cytochrome oxidase (COX) activity was compared with 1) the content of COX subunits III and IV and 2) 5-aminolevulinate synthase (ALAS) activity and mRNA content. In the plantaris muscle of female rats run daily for up to 28 days, ALAS activity was elevated 100% (P < 0.01) after 3 days and remained 150 and 125% higher (P < 0.001) after 7 and 28 days of running, respectively, than control. COX activity was also increased, but not until day 7 (40%; P < 0.05), and reached a maximal value 80% higher than control (P < 0.001) in the 28-day group. Compared with control, the content of COX subunit III and IV and ALAS mRNAs was not significantly changed by the training. The increased activities of COX and ALAS appear to be regulated by translational or posttranslational steps in the protein expression pathway. The induction of ALAS before COX suggests that the increased activity of COX may require increased synthesis of heme.  相似文献   

3.
The zebrafish Danio rerio is an important model system for genetic and developmental studies of the vertebrate central nervous system. Considerable knowledge concerning the embryonic development of the central nervous system of the zebrafish has accumulated in recent years. However, there is an apparent lack of information on the organization of the adult zebrafish brain. We have therefore recently studied in detail the neuroanatomy of the adult zebrafish. Here we compare the brains of the zebrafish and of the closely related and neurobiologically well-investigated goldfish, Carassius auratus. Two sensory systems, the visual and the gustatory systems, were identified as differing on the gross morphological and histological levels in the two species. The goldfish shows the simple (evolutionarily reduced) pattern of pretectal organization, and its gustatory system is massively enlarged. The pretectum of the zebrafish conforms to this simplified visual pretectal pattern, although the retention of some ancestral pretectal characters indicates a lesser degree of reduction of the visual system compared to the goldfish. The gustatory system shows many similarities with the evolutionarily derived and functionally specialized gustatory system of the goldfish. However, some peripheral and central gustatory characters are missing in the zebrafish, indicating a less specialized gustatory system.  相似文献   

4.
In order to assess the risk posed by chlorate in aquatic ecosystems, data on the effects of chlorate on aquatic organisms (microorganisms, algae, invertebrates, and fish) and mesocosm studies have been collated and critically reviewed. The geometric mean E(L)C50 values for both freshwater and marine species were (as ClO3-): microorganisms, 38,583 mg.liter-1; microalgae, 563 mg.liter-1; invertebrates, 2442 mg.liter-1; fish, 3815 mg.liter-1. Marine macro red algae were insensitive to chlorate, whereas marine macro brown algae (e.g., Fucus sp.) appeared to be exceptionally sensitive to chlorate, adverse long-term effects having been reported at concentrations as low as 0.015 mg ClO3-.liter-1. Evidence for the mechanism by which chlorate is thought to be particularly toxic to these species is also reviewed. It is concluded that, based on the species reported, chlorate is nontoxic (acute toxicity > 100 mg.liter-1) to most of the freshwater and marine species examined. However, chlorate is highly toxic (acute toxicity < 0.1 mg.liter-1) to certain macro brown algal species. For macro brown algae, the NOEC after 6 months was reported to be approximately 0.005 mg ClO3-.liter-1. It is also concluded that an improved understanding of the actual mode of action of chlorate in sensitive species is desirable. Together with further information on the environmental fate of chlorate, this will improve the risk assessment for chlorate in the aquatic environment.  相似文献   

5.
Pathologically asymmetrical P300 fields with right lateralized peaks were described in core schizophrenia as an expression of left-temporal functional deficits, while higher than normal amplitudes were found in cycloid psychosis. This latter finding appeared to be specific for cycloid psychosis and was explained by a generalized cerebral hyperarousal. Based on some psychopathological analogies with cycloid psychosis, and on the comparable pharmacological treatment of the acute episodes, a group of 19 manic patients was investigated immediately after remission and clinical stabilization of an episode. Patients with psychotic features were excluded to avoid overlaps with cycloid psychosis. Patients showed normal P300 amplitudes and no pathological asymmetries of the field, but more posterior positive areas compared to age- and sex-matched controls. This indicates that the neurophysiological changes underlying mania are different from both core schizophrenia and cycloid psychosis. Based on previous three-dimensional source location studies, this finding indicates that disinhibition due to reduced frontal lobe activity, and not hyperarousal, is the basic functional mechanism of manic disorders.  相似文献   

6.
As an increasing number of large prospective studies show a high accuracy of the sentinel node for the staging of the axilla in women with invasive breast cancer, there is no need to test the value of this new technique in a randomised trial. Much more emphasis should be given to a reliable implementation of the technique in general practice, requiring a closely co-operating multidisciplinary team meticulously performing the different steps of the technique. The guidelines designed by the Dutch Working Group on the Sentinel Node in Breast Cancer include a learning phase of--arbitrarily--50 procedures in patients also undergoing a complete axillary dissection. What remains is the need for a treatment trial aimed at reducing the morbidity of the treatment of axillary metastases while retaining equal regional tumour control and patient survival. As the indication for adjuvant systemic treatment has shifted from the N-stage to T-stage parameters (size, grade, mitotic activity), the axillary nodal status has become less important as a staging tool. Thus, comparison of surgery or radiotherapy of sentinel node positive patients in a randomised trial appears to be a logical next step.  相似文献   

7.
The QT interval has been studied in ECG in mouse and rat embryos during two stages of development. The QT interval during the early stage of development is prolonged and an ST segment clearly exists. Both disappear during fetal development and do not exist in adult animals in which the T wave immediately follows the QRS. Mammalian embryos have therefore been proposed as a model for the study of QT prolongation. It is suggested that the origin of the QT prolongation in the young embryos is caused by the prolonged duration of the action potentials of the primordial cardiac tissue. During embryonic development this tissue becomes organized as a conductive system surrounded by "neomyocardial" tissue with a shorter duration of action potential, which causes the shorter QT interval at this stage. Our working hypothesis is that the pathogenesis of the prolonged QT syndrome in children could be interpreted as an incomplete or delayed differentiation between the primordial or primordial-like myocardium retaining prolonged action potential duration, and "neomyocardium" with short duration.  相似文献   

8.
We describe a method for preparing nuclear spreads from cells of live, unfixed zebrafish embryos at the late-gastrula (approximately 8000 cell) stage of development. The method consists of a sequence of four steps: (1) a slow, gentle lysis, in low to moderate salt concentration, of cells and then nuclei, to release DNA-containing fibres; (2) spreading of the released fibres by a transverse fluid flow; (3) electrostatic, and possibly also covalent, attachment of the spread fibers to poly(L-lysine)-coated glass microscope slides; and (4) continued incubation to produce periodic cleavage of the DNA within the fibres, apparently through activation of endogenous nucleases. The nuclear spreads are imaged with epifluorescence, at a spatial resolution approaching the Rayleigh limit (approximately 230 nm for blue light). The epifluorescent signal is provided from Hoechst 33,258 bound specifically to the DNA, from a dye-coupled antibody conjugate bound specifically to histone H1 in the fibres, or from a DNA nick end-labelling assay. The spontaneous cleavage of DNA-containing fibres in step (4) of the above procedure can be blocked by the chelating agents EGTA and EDTA, by the caspase-2,3,7 inhibitor N-acetyl-Asp-Glu-Val-Asp-aldehyde, and by the caspase-1,4,5 inhibitors N-acetyl-Tyr-Val-Ala-Asp-aldehyde and N-acetyl-Tyr-Val-Ala-Asp-chloromethyl ketone. These data suggest that the spontaneous cleavage of fibres is catalysed by nucleases that become activated through a caspase-mediated mechanism. The involvement of caspase-dependent nucleases would suggest that an apoptosis pathway is activated in the spreads during their prolonged incubation. If bona fide apoptosis is induced in living zebrafish embryos by treatment with camptothecin (a topoisomerase I poison), and then nuclear spreads are prepared, we observe a similar fragmentation of the spread fibres. However, in this case the fragmentation is more rapid and complete. We hypothesize that, during the early phase of apoptosis, one or more endogenous nucleases are activated by a caspase-mediated mechanism. The nuclease(s) then specifically recognize and cleave a susceptible, periodically repeating feature of interphase chromatin.  相似文献   

9.
Reports results of an experiment with 12 visually-naive 5-12 wk. old kittens. Ss acquired guided reaching when provided with visual feedback from paw movements in an otherwise dark surround after, but not before, they had developed visually-guided locomotion. This sequence effect suggests that visual feedback from the forelimb is informative only within a body-centered spatial framework. A number of previous studies of adaptation to prismatic displacement of vision in humans are discussed. It is suggested that common constraints underlie certain results of the prism studies and the present evidence of a required sequence in acquisition of visually-guided behavior in the kitten. (16 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

10.
Some researchers of studies of the incidence of early visual experience on spatial abilities have demonstrated profound spatial deficits in early blind participants, whereas others have not found evidence of deleterious effects of early visual deprivation. The aims of this article are to (a) consider the theoretical background of these studies, (b) take stock of the divergent data, and (c) propose new means of investigation. The authors examine the reasons why vision plays a critical role in spatial cognition. They review the literature data. They also review the factors that could account for the discrepant data and the effects of the lack of early visual experience on brain functioning. They propose that the study of strategies is a valuable option to obtain insight into early blind persons' spatial impairment. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

11.
This theoretical article explores the impact of ethnic appearance on the nurse-client encounter from the perspective of Chicanas, women of Mexican descent. The issues raised for Chicanas, however, are applicable for members of many other ethnic groups, individuals whose identity is often constructed from the stereotypes and myths their appearance evokes. Ethnic minority women often experience a feeling of double jeopardy, enduring the consequences of living in a society that devalues both women and members of specific racial or ethnic groups. Research from nursing, counseling psychology, and sociology provide the bases for an examination of the mental health consequences of this double jeopardy. Narrative interaction, the sharing of personal stories, is offered as a therapeutic form of communication. Through narrative interactions, nurses may begin to understand the context of women's lives and learn what is meaningful for them, from their perspective. It is from the women themselves that nurses will begin to learn new meanings for their appearance and gain some understanding of their world.  相似文献   

12.
EpoDB is a database of genes expressed in vertebrate red blood cells. It is also a prototype for the creation of cell and tissue-specific databases from multiple external sources. The information in EpoDB obtained from GenBank, SWISS-PROT, Transfac, TRRD and GERD is curated to provide high quality data for sequence analysis aimed at understanding gene regulation during erythropoiesis. New protocols have been developed for data integration and updating entries. Using a BLAST-based algorithm, we have grouped GenBank entries representing the same gene together. This sequence similarity protocol was also used to identify new entries to be included in EpoDB. We have recently implemented our database in Sybase (relational tables) in addition to SICStus Prolog to provide us with greater flexibility in asking complex queries that utilize information from multiple sources. New additions to the public web site (http://www.cbil.upenn.edu/epodb) for accessing EpoDB are the ability to retrieve groups of entries representing different variants of the same gene and to retrieve gene expression data. The BLAST query has been enhanced by incorporating BLASTView, an interactive and graphical display of BLAST results. We have also enhanced the queries for retrieving sequence from specified genes by the addition of MEME, a motif discovery tool, to the integrated analysis tools which include CLUSTALW and TESS.  相似文献   

13.
Gathered measures of personal space from 74 children (ages 3, 5, and 7) when they approached boys or girls of their own age. A significant difference was found between the 3-yr-olds (who kept less distance from their age peers) and the 5- or 7-yr-olds. No other differences attributable to age were found. For all Ss, the sex of the interacting child was relevant in that less distance was kept from girls than from boys. Results are discussed in the light of learning and developmental processes. (22 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

14.
15.
BACKGROUND: In amphibians, the Nieuwkoop center--a primary inducing region--has a central role in the induction of dorsal mesodermal cells to form the Spemann organizer. In teleosts, such as the zebrafish, Danio rerio, the functional equivalent of the amphibian Spemann organizer is the dorsal shield. Historically, a small region of the teleost yolk syncytial layer (YSL), an extraembryonic tissue that underlies the entire blastoderm, has been implicated in dorsal shield specification. Difficulties in transplanting discrete regions of the YSL and the previous lack of localized expression patterns unique to the YSL have, however, hindered efforts to prove definitively that the YSL possesses Nieuwkoop-center-like activities. RESULTS: Here, we describe the isolation and analysis of a new homeobox gene, called nieuwkoid, which is first expressed immediately following the mid-blastula transition on the dorsal side of the zebrafish pregastrula embryo. We found that, by the onset of gastrulation, nieuwkoid expression becomes localized to a restricted region of the YSL, directly underlying the future dorsal shield. Mis-expression of nieuwkoid in early zebrafish embryos was found to be sufficient for the induction of ectopic organizer regions and secondary axes. Mis-expression of nieuwkoid by cell transplantation or by direct injection into the YSL led to the non-autonomous induction of ectopic organizer gene expression. CONCLUSIONS: The dynamic and restricted expression of the nieuwkoid gene, combined with its potent dorsalizing activity, suggests that nieuwkoid is an important component in the regionalization of the gastrula organizer, possibly characterizing and mediating an organizer-inducing/Nieuwkoop-center-like activity.  相似文献   

16.
OBJECTIVE: Abnormal uterine bleeding is a common and troublesome problem in human immunodeficiency virus (HIV)-infected women. We sought to evaluate endometrial pathology among HIV-infected women requiring hysterectomy to explore if endometritis may be common among these patients. METHODS: We performed a retrospective analysis of uterine pathology specimens obtained from HIV-infected and control patients requiring hysterectomy in two urban hospitals between 1988 and 1997 matched for age, surgical indication, and history of gonadotropin-releasing hormone (GnRH) use. Cases were evaluated for the presence of plasma cells and assigned a grade between 0 and 3. RESULTS: Indications included cervical dysplasia (4), carcinoma in situ (2), abnormal uterine bleeding (3), and adnexal mass (3). Some degree of abnormal uterine bleeding occurred in all cases. Plasma cell endometritis was twice as common in HIV-infected women compared to HIV-negative specimens (11/11 versus 11/22) (P < 0.05). Plasma cell endometritis was also of a higher grade in specimens from HIV-infected women than in controls (P = 0.001). CONCLUSION: Chronic endometritis was common and of a higher grade among HIV-infected women requiring hysterectomy in our series. Diagnosis and treatment of endometritis should be considered in HIV-infected women with uterine bleeding and/or tenderness. We speculate that antiretroviral and/or antimicrobial treatment for endometritis may effectively treat endometritis and eliminate the need for surgery in some HIV-infected women. We suggest that consideration and treatment of endometritis in HIV-1 infected women being evaluated for possible hysterectomy has the potential to reduce costs and morbidity for patients and providers who may be exposed during surgical procedures.  相似文献   

17.
This article explains the importance of comparing statistics from year to year, especially when analyzing a practice for purchase, sale, partnership, or management. This is an invaluable tool that becomes a yardstick for measurement and should never be omitted or dispensed with.  相似文献   

18.
Hari and Jousmaki (1996) found that motor activity is initiated more efficiently in response to stimuli located on the responding limb as opposed to near the limb. Our research investigated the basis for this difference in spatial coding. We conducted 8 experiments using virtual reality to manipulate the visual feedback resulting from limb movement (spatial location, limb appearance, and nature of response consequences). Our findings replicated the Hari and Jousmaki (1996) effect to reveal that visual appearance and correspondence between the visual and felt position of the limbs was inconsequential. However, it was crucial that visual feedback was a predictable consequence of movement. When this predictability was present, the distinction between the space on the limb (predictable surface) and off the limb (rest of the environment) emerged. We suggest that there may be a functional distinction in coding of space that is and is not predictably controlled by the individual. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

19.
The inferior border of the thyroid cartilage and the superior rim of the cricoid arch are connected by the cricothyroid membrane and partly covered by the cricothyroid muscles ventrally. This region has been termed the cricothyroid space (CS) and is important with regard to surgical procedures, the spread of laryngeal cancer and traumatic lesions of the larynx. The precise topographic relations of the CS were investigated in plastinated serial sections of 21 normal adult human specimens. The CS consists of a caudal and a cranial portion, which are different with regard to their cartilaginous framework and their relationship to intralaryngeal structures. The caudal portion is bordered by the cricoid cartilage and reveals a complete separation of extra- and intralaryngeal regions by the cricothyroid membrane. It provides an easy access to the subglottic airways. The cranial portion of the CS is mainly bordered by the thyroid cartilage. It is characterized by a gap lateral to the median cricothyroid ligament. This allows a connection of extra- and intralaryngeal adipose tissue. There, extralaryngeal extension of laryngeal cancer preferentially occurs. Traumatic subglottic ruptures of the larynx involve both the caudal and cranial portions of the CS, which often results in extensive scar tissue formation.  相似文献   

20.
In 34 inpatients, 22 with diagnosis of rheumatoid arthritis according to revised ACR criteria and 12 with diagnosis of other diseases without affection of the hands served like control group we measured grip strength in 4 time period during the day (7, 11, 15, 19 hours) with the Martin's vigorimeter. Mean grip strength value was statistically lower in patients with rheumatoid arthritis in all four time periods (P < 0.005). There is general trend of the rising grip strength since morning to evening without statistically relevance. Grip strength firmly linear negatively correlated with the grade of morning stiffness.  相似文献   

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