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1.
We have shown that normal and human papillomavirus (HPV) type 16 immortalized human foreskin keratinocytes are growth inhibited by tumor necrosis factor alpha (TNF-alpha), whereas HPV-18- and SV40-immortalized keratinocytes are resistant to this cytokine (1). In this report, we investigated the expression of mitotic regulatory proteins, such as cyclin A, cyclin B, and p34cdc2. After exposure to TNF-alpha, normal and HPV-16-immortalized cells exhibited a dramatic decrease in the expression of these proteins. In contrast, no alteration in the levels of these proteins was observed after treatment of the resistant cell lines, as well as two HPV-positive cervical carcinoma cell lines. Expression of cyclin E does not seem to be modulated by TNF-alpha in any of the cells tested. On the other hand, cyclin D1, expression is slightly increased in normal keratinocytes and in the HPV-16-immortalized cells, whereas no alteration was observed in the HPV-18-transfected cells. The phosphorylation state of pRb correlated with cell growth; sensitive cells, which accumulate in G0-G1, after exposure to TNF-alpha, exhibited an accumulation of hypophosphorylated pRb, whereas no effect on pRb phosphorylation was observed for HPV-18-immortalized cells. These results clearly correlate with TNF-alpha-induced growth arrest in G0-G1.  相似文献   
2.
Reports an error in "What is in a word? No versus Yes differentially engage the lateral orbitofrontal cortex" by Nelly Alia-Klein, Rita Z. Goldstein, Dardo Tomasi, Lei Zhang, Stephanie Fagin-Jones, Frank Telang, Gene-Jack Wang, Joanna S. Fowler and Nora D. Volkow (Emotion, 2007[Aug], Vol 7[3], 649-659). The supplemental materials link should appear as follows: http://dx.doi.org/10.1037/1528-3542.7.3.649.supp. (The following abstract of the original article appeared in record 2007-11660-018.) The words "No" and "Yes" are involved in conditioning to prohibit or encourage behavior, respectively. The authors, therefore, hypothesized that these words would be attributed to endogenous valence, activating neuronal circuits involved with valence and emotional control. Functional MRI (fMRI) at 4 Tesla was used to record regional brain activity while participants were exposed to emphatic vocalizations of the words. Results showed that No and Yes were associated with opposite brain-behavior responses; while No was negatively valenced, produced slower response times, and evoked a negative signal in the right lateral orbitofrontal cortex (OFC), Yes was positively valenced, produced faster response times, and evoked a positive signal in a contiguous region of the OFC. Attribution of negative valence to No and trait anger control were associated with increased responsivity of the OFC to No. Inasmuch as sensitivity to the prohibitive command No develops during childhood through interaction with primary caregivers as the first social objects, our findings may implicate the lateral OFC in the neurobiology of emotion regulation and subsequent social development. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Hemispheric involvement in reasoning abilities has been debated for some time, and it remains unclear whether the right hemisphere's involvement in problem solving is modality specific or dependent on the type of spatial reasoning required. In the current study, 2 types of nonverbal reasoning abilities were examined, spatial reasoning and proportional reasoning, in 109 patients with cerebrovascular disease that was confined to either the right or the left hemisphere or was diffuse in nature. Results indicated that no lateralizing effects were present based on type of spatial reasoning. Findings are consistent with the suggestion that higher order cognitive processes involved in nonverbal abstraction and problem solving are not strongly lateralized to the right hemisphere but rather are more generally distributed throughout the cortex. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
5.
OBJECTIVE: Chronic Q fever is seldom recognized; before 1989, only 234 cases had been reported in the literature. The 92 cases of chronic Q fever collected at the French National Reference Center for Rickettsioses from 1982 through 1990 represent the largest series ever reported. PATIENTS: The patients included in the study were diagnosed between July 31, 1982, and August 1, 1990, at the French National Reference Center for Rickettsioses as having chronic Q fever by the following criteria: presence of antibody against Coxiella burnetii phase I antigen at a titer greater than or equal to 800 for IgG and 50 for IgA by the indirect immunofluorescence test. Epidemiologic, clinical, laboratory, and treatment data were collected from 39 different collaborative hospitals throughout France. MAIN OUTCOME MEASURE: For each serologically selected patient, a computerized questionnaire was utilized to record 188 different items of demographic, epidemiologic, clinical, laboratory, and therapeutic data, which were analyzed. RESULTS: Chronic Q fever occurs more frequently in city dwellers than in rural inhabitants, and exposure to domestic ruminants and raw milk is an important feature. Immunocompromising conditions (20.2%) and underlying heart disease (88.4%) or vascular disease are the most important risk factors to consider in potential cases of chronic Q fever. The mortality in these patients with endocarditis was high (23.5%). The clinical spectrum of 84 patients included 57 cases of endocarditis, three cases of vascular prosthesis infection, three cases of aneurysmal infection, three cases of osteoarthritis, four cases with lung localizations, nine asymptomatic cases, three cases of hepatitis, and two cases with cutaneous forms of the disease. CONCLUSIONS: In patients with unexplained fever, negative blood cultures, and a history of underlying vascular or cardiac disease, Q fever should be considered.  相似文献   
6.
When the Etest was compared to broth microdilution for susceptibility testing of Streptococcus pneumoniae, levofloxacin, erythromycin, and penicillin results correlated for both methods; azithromycin and clarithromycin showed discrepancies of > or = 2 dilutions for 95.8% and 31.5% of the isolates, respectively. Levofloxacin was active against 141 of 142 isolates (< or = 2.0 micrograms/ml), making it a potentially useful new fluoroquinolone.  相似文献   
7.
The major goal of this investigation was to collect statistically-based anthropometry describing the kinematics of the human hand and to model this anthropometry as a function of external hand measurements, so that it may be predicted noninvasively. Joint centres were anatomically estimated as the centre of curvature of the head of the bone proximal to the given joint. Joint centres determined using Reuleaux's method for PIP and DIP were within 1.4 mm of this anatomical estimate. Models using bone length as the independent variable explain more than 97% of the variability in the anatomically estimated joint centre position along the mid-line of the bone. Models for estimating the lengths of the kinematic segments using external hand length as the independent variable account for between 49 and 99% of the variability in segment length. Models for estimating the axial location of the finger MCP and thumb CMC joints with respect to the distal wrist crease using external hand length as the independent variable account for between 82 and 96% of the variability in these locations. Models for estimating the radio-ulnar location of the finger MCP and thumb CMC joints with respect to the long axis of the third metacarpal using external hand breadth as the independent variable account for between 30 and 74% of the variability in these locations.  相似文献   
8.
Detection performance of the reduced-rank linear predictor ROCKET   总被引:6,自引:0,他引:6  
This paper assesses the frequency detection capabilities of a new signal-dependent reduced-rank linear predictor applied to autoregressive spectrum estimation. The new technique is called reduced-order correlation kernel estimation technique (ROCKET). Its detection performance is examined by comparison to a full-rank autoregressive (FR-AR) estimator and two reduced-rank principal component autoregressive (PC-AR) estimators based on both the standard signal-independent version and a modified signal-dependent method. The performance of the new autoregressive estimator is also compared as a function of rank to the popular pseudo-spectrum estimator MUSIC. The performance metrics examined are the probability of detection (P/sub D/) and the false alarm rate (FAR) of detecting the spatial frequencies of plane waves impinging on a uniform line array in additive white Gaussian noise. These metrics are studied as a function of subspace rank, sample support, and signal-to-noise ratio (SNR). Simulations show that the signal-dependent reduced-rank estimators significantly outperform both the signal-independent version of PC-AR and the FR-AR estimator for low sample support and low SNR environments. One notable characteristic of ROCKET that highlights its distinct subspace selection is its performance as a function of subspace rank. It is observed that for equal powered signals, its peak performance is nearly invariant to signal rank and that at almost any subspace rank ROCKET meets or exceeds FR-AR performance. This provides an extra degree of robustness when the signal rank is unknown.  相似文献   
9.
The authors examined whether young, recently discharged schizophrenic patients from high (n?=?34) and low (n?=?14) expressed emotion (EE) families differ in their level of subclinical symptomatology during a direct interaction task. Compared with patients from low-EE homes, patients from high-EE homes showed significantly more odd and disruptive behavior with family members. High-EE relatives were more likely than low-EE relatives to respond with criticism to the first unusual thought verbalized by the patient; when this occurred, the probability of a second unusual thought was augmented. Results suggest that high-EE family members may display negative attitudes toward patients in part because they are exposed to higher levels of unusual or disruptive behavior than low-EE relatives. The data also support a bidirectional, transactional model of the relationship between relatives' EE and patient psychopathology. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
10.
Zusammenfassung:  Mit Verwirklichung des gemeinsamen Binnenmarktes ab 01.01.1993 wurde ein freier Warenverkehr innerhalb der Europ?ischen Union mit Wegfall zwischenstaatlicher Kontrollen im tiergesundheitlichen und lebensmittelsicher-heitsrelevanten Bereich realisiert. In allen Mitgliedstaaten soll ein vergleichbares Schutzniveau bzgl. des gesundheitlichen Verbraucherschutzes erfüllt werden. In der Praxis hat sich jedoch gezeigt, dass die Anwendung des EU-Rechtes in den neuen Mitgliedstaaten teilweise noch Schwierigkeiten bereitet. Vor diesem Hintergrund sind von der Kommission verschiedene Fortbildungs- und F?rderma?nahmen mit der Zielsetzung entwickelt worden, vorhandene Defizite in diesem Bereich zu minimieren. Dazu z?hlen die seit 1998 von der Kommission initiierten sog. Twinning-Projekte (Verwaltungspartnerschaften) zwischen Beh?rden alter und neuer Mitgliedstaaten. Seit diesem Zeitpunkt wurden mehr als 1100 Twinning-Projekte durchgeführt, davon fast 300 Projekte unter deutscher Leitung (Schwerpunkt: Landwirtschaftlicher Bereich). Im vorliegenden Artikel werden Bedeutung und Inhalte von Twinning-Projekten im Veterin?r- und Lebensmittelbereich dargestellt. Ihr formales Verfahren sowie die in den Verwaltungspartnerschaften gewonnenen Erfahrungen und M?glichkeiten der Verbesserung werden erl?utert.
The Twinning-Programme of the European Union: Experiences in the implementation of Twinning- projects in veterinary and food affairs. Since 01.01.1993 a common market was built up within the EU with cancelling of border controls of foods, animal products and living animals. An equal level of consumer protection should be established in all member states. In practice however, implementation of EU food and feed legislation in the new member states often causes problems. To reduce deficiencies in this field, the EU commission developed several measures of training and strenghtening for new member states. These measures include the so called Twinning-projects between competent authorities of old and new member states, which have been initiated since 1998. More than 1100 Twinning projects have been performed so far, including about 300 projects in Germany (with emphasis on agriculture). This article shows meaning and contents of Twinning-projects in the field of veterinary and food affairs. Formal procedures, experiences and possibilities of improvement of twinning-projects are described.


Eingegangen: 16. Januar 2008  相似文献   
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