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11.
In cats anesthetized with chloralose-urethane, the central respiratory chemoreceptors were exposed to mock CSF of pH 7.02, 7.20, or 7.57. The right carotid body was simultaneously stimulated by intracarotid injections of 40, 80, or 160 μg sodium cyanide in 200 μl Ringer solution. The left carotid nerve and, in some animals, both vagosympathetic truncs were dissected. It could be demonstrated the the increase in ventilation produced by application of NaCN to the peripheral chemoreceptors is significantly larger at high than at low mock CSF pH (i.e. at low than at high central stimulus intensity). In vagotomized cats the responses of VT and gelai to NaCN similarly depend upon CSF pH; they are somewhat larger, though, than in intact animals. These results are discussed as compared with results reported by different authors. Supported by the Deutsche Forschungsgemeinschaft (Be 477)  相似文献   
12.
Reception and production aspects of musical ability were assessed in two studies of left cerebro-vascular accident (LCVA) and right cerebro-vascular accident (RCVA) patients and controls. Musical tasks included perception of rhythm and pitch variations in familiar and unfamiliar tunes; and production of a well-known song, three original melodies, and imitation of rhythm patterns. The only "laterality of music" effect to emerge in the first study was impaired ability in LVCA patients to correctly perceive rhythmic changes. In the second study LCVAs were poorer than the other two groups in the singing of novel melodies, and both lesioned groups were poorer than controls in singing a familiar tune and in tapping rhythms. Premorbid musical ability was significantly related to performance over all groups combined. The RCVA group showed an inconsistent pattern of performance. The LCVA group was consistently more impaired over all tasks but apart from the aforementioned effects this was nonsignificant. It is argued that laterality effects for music processing cannot be reliably established.  相似文献   
13.
The authors present case reports demonstrating the trilevel utility of the inferiorly based rectus abdominis musculocutaneous flap in the closure of complex wounds involving the pelvis, groin, and femur that had failed previously or were not amenable to traditional closure techniques. The use of the rectus abdominis flap was especially advantageous for achieving infection eradication and large dead space closure. Additionally they present the emerging technique of power color Doppler imaging as a valuable tool in preoperative flap planning. This technique is particularly useful in evaluating the candidacy for rectus abdominis musculocutaneous flap placement of patients with a prior history of abdominal surgeries, trauma, infection, irradiation, or other conditions that might compromise the patency of the deep inferior epigastric vessels.  相似文献   
14.
Nine azaphilones designated RP-1551-1, -2, -3, -4, -5, -6, -7, -M1, and -M2 were isolated from the culture broth of Penicillium sp. SPC-21609 as inhibitors of PDGF binding to its receptor. RP-1551s inhibit the binding of PDGF AA to the extracellular domain of PDGF alpha-receptor with IC50 values ranging from 0.1 to 2 microM without affecting PDGF BB binding to the extracellular domain of PDGF beta-receptor. PDGF binding was not restored after the PDGF alpha-receptor extracellular domain was washed in an attempt to remove the RP-1551-1 bound to the receptor. This result suggests that RP-1551-1 may irreversibly interact with the PDGF alpha-receptor. Since many azaphilone compounds possess high reactivity with an amino group, RP-1551-1 may prevent PDGF AA binding by reacting with amino groups on the alpha-receptor extracellular domain.  相似文献   
15.
Developmental neurology is one of the major areas of neuropediatrics and is among other things (legally) responsible for monitoring the motor, cognitive and psychosocial development of all infants using standardized monitoring investigations. The special focus is on infants born at risk and/or due to premature birth before 32 weeks of gestation or a birth weight less than 1500?g. Early diagnosis of deviations from normal, age-related development is a prerequisite for early interventions, which may positively influence development and the long-term biopsychosocial prognosis of the patients. This article illustrates the available methods in developmental neurology with a focus on recent developments. Particular attention is paid to the predictive value of general movements (GM). The current development of markerless automated detection of spontaneous movements using conventional depth imaging cameras is demonstrated. Differences in spontaneous movements in infants at the age of 12 weeks are illustrated and discussed exemplified by three patients (healthy versus genetic syndrome versus cerebral palsy).  相似文献   
16.
Although addiction develops in a considerable number of regular cocaine users, molecular risk factors for cocaine dependence are still unknown. It was proposed that establishing drug use and memory formation might share molecular and anatomical pathways. Alpha-Ca2+/calmodulin-dependent protein kinase-II (αCaMKII) is a key mediator of learning and memory also involved in drug-related plasticity. The autophosphorylation of αCaMKII was shown to accelerate learning. Thus, we investigated the role of αCaMKII autophosphorylation in the time course of establishing cocaine use-related behavior in mice. We found that αCaMKII autophosphorylation-deficient αCaMKIIT286A mice show delayed establishment of conditioned place preference, but no changes in acute behavioral activation, sensitization or conditioned hyperlocomotion to cocaine (20 mg kg−1, intraperitoneal). In vivo microdialysis revealed that αCaMKIIT286A mice have blunted dopamine (DA) and blocked serotonin (5-HT) responses in the nucleus accumbens (NAcc) and prefrontal cortex after acute cocaine administration (20 mg kg−1, intraperitoneal), whereas noradrenaline responses were preserved. Under cocaine, the attenuated DA and 5-HT activation in αCaMKIIT286A mice was followed by impaired c-Fos activation in the NAcc. To translate the rodent findings to human conditions, several CAMK2A gene polymorphisms were tested regarding their risk for a fast establishment of cocaine dependence in two independent samples of regular cocaine users from Brazil (n=688) and Switzerland (n=141). A meta-analysis across both samples confirmed that CAMK2A rs3776823 TT-allele carriers display a faster transition to severe cocaine use than C-allele carriers. Together, these data suggest that αCaMKII controls the speed for the establishment of cocaine''s reinforcing effects.  相似文献   
17.
Conventional immunotherapy (IT) is effective in treating allergic rhinitis, allergic asthma, and chronic rhinosinusitis. Disadvantages include poor compliance, delayed efficacy, and patient frustration. Rush IT, or rapid desensitization, offers the advantages of rapid response, improved compliance, and cost-effectiveness. Although premedication with corticosteroids and antihistamines dramatically reduces systemic reactions, safety remains a primary concern. Two separate half-day schedules with minor differences were used to rapidly desensitize 893 patients (aged 1.5-77 years) in two typical outpatient settings equipped to treat anaphylaxis. All patients exhibited positive skin-prick tests to perennial and seasonal allergens. Diagnoses included allergic rhinitis (857/96%), allergic asthma (505/57%), and chronic rhinosinusitis (384/43%). Five hundred sixty-eight patients were premedicated with prednisone and HI-antihistamine for 3 days. Three hundred twenty-five patients were premedicated for 3 days with prednisone and H1- and H2-blockade. The protocol's final dose ranged from 0.1 to 0.5 mL of a 1:1000 dilution of extracts manufactured by ALK and Greer Laboratories. Patients continued on to higher doses by resuming a conventional schedule. Eighteen patients (2.0%) experienced a mild systemic reaction. All responded to subcutaneous epinephrine and/or nebulized albuterol and were sent home after observation. One patient (0.1%) experienced true anaphylaxis and received appropriate treatment and observation. Our experience with rush IT confirms that maintenance IT can be reached quickly and safely under careful supervision. Caution must be exercised when using this procedure because anaphylaxis does occur. Systemic reactions occur less frequently using a lower targeted final dose than previously described in the literature.  相似文献   
18.
19.
Cognitive processes that require spatial information rely on synaptic plasticity in the dorsal CA1 area (dCA1) of the hippocampus. Since the function of the hippocampus is impaired in aged individuals, it remains unknown how aged animals make spatial choices. Here, we used IntelliCage to study behavioral processes that support spatial choices of aged female mice living in a group. As a proxy of training-induced synaptic plasticity, we analyzed the morphology of dendritic spines and the expression of a synaptic scaffold protein, PSD-95. We observed that spatial choice training in young adult mice induced correlated shrinkage of dendritic spines and downregulation of PSD-95 in dCA1. Moreover, long-term depletion of PSD-95 by shRNA in dCA1 limited correct choices to a reward corner, while reward preference was intact. In contrast, old mice used behavioral strategies characterized by an increased tendency for perseverative visits and social interactions. This strategy resulted in a robust preference for the reward corner during the spatial choice task. Moreover, training decreased the correlation between PSD-95 expression and the size of dendritic spines. Furthermore, PSD-95 depletion did not impair place choice or reward preference in old mice. Thus, our data indicate that while young mice require PSD-95-dependent synaptic plasticity in dCA1 to make correct spatial choices, old animals observe cage mates and stick to a preferred corner to seek the reward. This strategy is resistant to the depletion of PSD-95 in the CA1 area. Overall, our study demonstrates that aged mice combine alternative behavioral and molecular strategies to approach and consume rewards in a complex environment.SIGNIFICANCE STATEMENT It remains poorly understood how aging affects behavioral and molecular processes that support cognitive functions. It is, however, essential to understand these processes to develop therapeutic interventions that support successful cognitive aging. Our data indicate that while young mice require PSD-95-dependent synaptic plasticity in dCA1 to make correct spatial choices (i.e., choices that require spatial information), old animals observe cage mates and stick to a preferred corner to seek the reward. This strategy is resistant to the depletion of PSD-95 in the CA1 area. Overall, our study demonstrates that aged mice combine alternative behavioral and molecular strategies to approach and consume rewards in a complex environment. Second, the contribution of PSD-95-dependent synaptic functions in spatial choice changes with age.  相似文献   
20.
Journal of Neurology - To evaluate the diagnostic accuracy and safety of extended stereotactic brain biopsy (ESBB) in a single center cohort with suspected primary angiitis of the central nervous...  相似文献   
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