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171.
Steven Stites Lisa Vansaghi Susan Pingleton Glendon Cox Anthony Paolo 《Academic medicine》2005,80(12):1100-1106
The authors report the development of a new metric for distributing university funds to support faculty efforts in education in the department of internal medicine at the University of Kansas School of Medicine. In 2003, a committee defined the educational value unit (EVU), which describes and measures the specific types of educational work done by faculty members, such as core education, clinical teaching, and administration of educational programs. The specific work profile of each faculty member was delineated. A dollar value was calculated for each 0.1 EVU. The metric was prospectively applied and a faculty survey was performed to evaluate the faculty's perception of the metric. Application of the metric resulted in a decrease in university support for 34 faculty and an increase in funding for 23 faculty. Total realignment of funding was US$1.6 million, or an absolute value of US$29,072 +/- 38,320.00 in average shift of university salary support per faculty member. Survey results showed that understanding of the purpose of university funding was enhanced, and that faculty members perceived a more equitable alignment of teaching effort with funding. The EVU metric resulted in a dramatic realignment of university funding for educational efforts in the department of internal medicine. The metric was easily understood, quickly implemented, and perceived to be fair by the faculty. By aligning specific salary support with faculty's educational responsibilities, a foundation was created for applying mission-based incentive programs. 相似文献
172.
Bertini M Ferrara M De Gennaro L Curcio G Fratello F Romei V Pauri F Rossini PM 《Journal of sleep research》2004,13(1):31-36
Transcranial magnetic stimulation (TMS) is a recently established technique in the neurosciences that allows the non-invasive assessment, among other parameters, of the excitability of motor cortex. Up to now, its application to sleep research has been very scarce and because of technical problems it provided contrasting results. In fact delivering one single suprathreshold magnetic stimulus easily awakes subjects, or lightens their sleep. For this reason, in the present study we assessed motor thresholds (MTs) upon rapid eye movement (REM) and non-rapid eye movement (NREM) sleep awakenings, both in the first and in the last part of the night. Taking into account that a full re-establishment of wake regional brain activity patterns upon awakening from sleep needs up to 20-30 min, it is possible to make inferences about the neurophysiological characteristics of the different sleep stages by analyzing the variables of interest immediately after provoked awakenings. Ten female volunteers slept in the lab for four consecutive nights. During the first night the MTs were collected, following a standardized procedure: 5 min before lights off, upon stage 2 awakening (second NREM period), upon REM sleep awakening (second REM period), upon the final morning awakening (always from stage 2). Results showed that MTs increased linearly from presleep wakefulness to REM sleep awakenings, and from the latter to stage 2 awakenings. There was also a time-of-night effect on MTs upon awakening from stage 2, indicating that MTs decreased from the first to the second part of the night. The increase in corticospinal excitability across the night, which parallels the fulfillment of sleep need, is consistent with the linear decrease of auditory arousal thresholds during the night. The maximal reduction of corticospinal excitability during early NREM sleep can be related to the hyperpolarization of thalamocortical neurons, and is in line with the decreased metabolic activity of motor cortices during this sleep stage. On the contrary, the increase of MTs upon REM sleep awakenings should reflect peripheral factors. We conclude that our findings legitimate the introduction of the TMS technique as a new proper tool in sleep research. 相似文献
173.
Molecular epidemiology of sequential outbreaks of Acinetobacter baumannii in an intensive care unit shows the emergence of carbapenem resistance 总被引:15,自引:0,他引:15 下载免费PDF全文
Zarrilli R Crispino M Bagattini M Barretta E Di Popolo A Triassi M Villari P 《Journal of clinical microbiology》2004,42(3):946-953
The molecular epidemiology of multidrug-resistant Acinetobacter baumannii was investigated in the medical-surgical intensive care unit (ICU) of a university hospital in Italy during two window periods in which two sequential A. baumannii epidemics occurred. Genotype analysis by pulsed-field gel electrophoresis (PFGE) of A. baumannii isolates from 131 patients identified nine distinct PFGE patterns. Of these, PFGE clones B and I predominated and occurred sequentially during the two epidemics. A. baumannii epidemic clones showed a multidrug-resistant antibiotype, being clone B resistant to all antimicrobials tested except the carbapenems and clone I resistant to all antimicrobials except ampicillin-sulbactam and gentamicin. Type 1 integrons of 2.5 and 2.2 kb were amplified from the chromosomal DNA of epidemic PFGE clones B and I, respectively, but not from the chromosomal DNA of the nonepidemic clones. Nucleotide analysis of clone B integron identified four gene cassettes: aacC1, which confers resistance to gentamicin; two open reading frames (ORFs) coding for unknown products; and aadA1a, which confers resistance to spectinomycin and streptomycin. The integron of clone I contained three gene cassettes: aacA4, which confers resistance to amikacin, netilmicin, and tobramycin; an unknown ORF; and bla(OXA-20), which codes for a class D beta-lactamase that confers resistance to amoxicillin, ticarcillin, oxacillin, and cloxacillin. Also, the bla(IMP) allele was amplified from chromosomal DNA of A. baumannii strains of PFGE type I. Class 1 integrons carrying antimicrobial resistance genes and bla(IMP) allele in A. baumannii epidemic strains correlated with the high use rates of broad-spectrum cephalosporins, carbapenems, and aminoglycosides in the ICU during the study period. 相似文献
174.
175.
Paolo Cerretelli Pietro Enrico di Prampero 《Pflügers Archiv : European journal of physiology》1988,412(3):270-276
Frog (Rana esculenta, L.) gastrocnemii (161 pairs) or sartorii (8 pairs) were stimulated by intermittent tetani at 10°C (20 Hz, supramaximal intensity, N2 atmosphere) isometrically (IM) or isotonically (IT) for various durations (6–30 s) at different tensions (0.05–1.00 P0=maximal IM tension at resting length,l
o). The energy expenditure (E) was measured from ATP and phosphocreatine breakdown and the high energy phosphate equivalent of lactic acid production. Both in IM and IT conditions,E was found to be a linear function of the summated tetanus duration (t):E=a+b t, whereb is the energy cost of tension maintenance. For the gastrocnemius, both in IM and IT,b was independent of the tension developed and equal to 0.45 mol P · g–1 · s–1, whereas for the sartoriusb was tension-dependent, varying between 0.58 and 0.28 mol P · g–1 · s–1 for P0 and 0.18 P0, respectively. The constancy of theb value in muscles with pennate structure may be tentatively attributed, at least in part, to the greater internal energy dissipation, regardless of the tension developed. The terma of the above equation is due to all time-independent processes of muscle contraction, i.e.: (1) activation energy; (2) internal work and (3) external work (in IT only). Based on the measured value ofa and on the work performed, the mechanical equivalent of P splitting was calculated as 17.7 kJ · mol–1, a figure close to that previously obtained on frog sartorius (16.7 kJ · mol–1) and dog gastrocnemius (19.2 kJ · mol–1) When taking into account the energy due to the activation processes, the calculated net mechanical equivalent of P splitting amounted to 25.5 kJ · mol–1. 相似文献
176.
Sclerosteosis: report of a case in a black African man 总被引:3,自引:0,他引:3
Paolo Tacconi Paola Ferrigno Luigi Cocco Antonino Carinas Giorgio Tamburini Paolo Bergonzi Marcello Giagheddu 《Clinical genetics》1998,53(6):497-501
Sclerosteosis is a rare genetic disorder of bone modelling, similar to, but distinct from, van Buchem disease; it has been described almost exclusively in Afrikaners of South Africa, a white population of Dutch ancestry. Isolated cases have been reported in a girl in Japan, a boy in Spain, and in multiracial families in Brazil and USA.
Here we report a case of sclerosteosis in a black man born in Senegal. He presented with the full features of the disease: tall stature; syndactyly; nail dysplasia; massive sclerosis of the long tubular bones, the ribs, the pelvis and the skull; multiple cranial nerve involvement: optic atrophy, facial palsy and trigeminal neuralgia. Radiologic examination, visual and brainstem auditory evoked potentials, computerized tomography and magnetic resonance imaging of the skull were performed. This seems to be the first case of the disease in a black African individual, with no known relationship with Dutch ancestry. 相似文献
Here we report a case of sclerosteosis in a black man born in Senegal. He presented with the full features of the disease: tall stature; syndactyly; nail dysplasia; massive sclerosis of the long tubular bones, the ribs, the pelvis and the skull; multiple cranial nerve involvement: optic atrophy, facial palsy and trigeminal neuralgia. Radiologic examination, visual and brainstem auditory evoked potentials, computerized tomography and magnetic resonance imaging of the skull were performed. This seems to be the first case of the disease in a black African individual, with no known relationship with Dutch ancestry. 相似文献
177.
Freer G Giannecchini S Tissot A Bachmann MF Rovero P Serres PF Bendinelli M 《Virology》2004,322(2):360-369
Immunogenicity of the tryptophan-rich motif (TrpM) in the membrane-proximal ectodomain of the transmembrane (TM) glycoprotein of feline immunodeficiency virus (FIV) was investigated. Peptide 59, a peptide containing the TrpM of the TM of FIV, was covalently coupled to Qbeta phage virus-like particles (Qbeta-59) in the attempt to induce potent anti-TrpM B cell responses in cats. All Qbeta-59 immunized cats, but not cats that received a mixture of uncoupled Qbeta and peptide 59, developed antibodies that reacted with a same epitope in extensive binding and binding competition assays. The epitope recognized was composed of three amino acids, two of which are adjacent. However, Qbeta-59-immune sera failed to recognize whole FIV in all binding and neutralization assays performed. Furthermore, no reactivity against the TrpM was detected by screening sera from FIV-infected cats that had reacted with TM peptides, confirming that this epitope does not seem to be serologically functional in the FIV virion. The data suggest that TrpM may not be a suitable target for antiviral vaccine design. 相似文献
178.
Ansaldi F Bacilieri S Amicizia D Valle L Banfi F Durando P Sticchi L Gasparini R Icardi G Crovari P 《Journal of medical virology》2004,74(1):141-146
Although the haemagglutination inhibition assay is considered the "gold standard" for antigenic characterisation of influenza viruses, some limitations of this technique are well known. A new microneutralisation assay, as a tool for antigenic characterisation of influenza B viruses, has been standardised and its performance evaluated in comparison with the haemagglutination inhibition test in the light of molecular characterisation of the haemagglutinin. Twelve B viruses belonging to the two lineages and the four sub-lineages discriminated by phylogenetic analysis of HA were tested. The microneutralisation assay clearly distinguishes viruses belonging to different lineages and, in addition, discriminates strains belonging to different sub-lineages that are poorly or not discriminated using the haemagglutination inhibition test. This new microneutralisation assay could provide a useful tool for antigenic characterisation of circulating influenza viruses and contribute, together with the haemagglutination inhibition test and sequence analysis of the haemagglutinin and neuraminidase, in the choice of the strain for use in vaccine composition. 相似文献
179.
Connexins are homologous four-transmembrane-domain proteins and major components of gap junctions. We recently identified mutations in either GJB3 or GJB4 genes, encoding respectively connexin 31 (Cx31) or 30.3 (Cx30.3), as causally involved in erythrokeratodermia variabilis (EKV), a mostly autosomal dominant disorder of keratinization. Despite slight differences, phenotypes of EKV Mendes Da Costa (Cx31) and EKV Cram-Mevorah (Cx30.3) show major clinical overlap and both Cx30.3 and Cx31 are expressed in the upper epidermal layers. These similarities suggested to us that Cx30.3 and Cx31 may interact at a molecular level. Indeed, expression of wild-type Cx30.3 in HeLa cell resulted only in minor amounts of protein addressed to the plasma membrane. Mutant Cx30.3 was hardly detectable and disturbed intercellular coupling. In sharp contrast, co-expression of both wild-type proteins led to a gigantic increase of stabilized heteromeric gap junctions. Furthermore, co-expressed wild-type Cx30.3 and Cx31 coprecipitate, which demonstrates a physical interaction. Inhibitor experiments revealed that this interaction begins in the endoplasmic reticulum. These results not only provide new insights into epidermal connexin synthesis and polymerization, but also allow a novel molecular explanation for the similarity of EKV phenotypes. 相似文献
180.
Barbaresi P 《Journal of neurocytology》2005,34(6):471-487
Immunocytochemical and electron microscopic methods were used to study the GABAergic innervation in adult cat periaqueductal
gray matter (PAG). A mouse monoclonal antibody against γ -aminobutyric acid (GABA) was used to visualize the inhibitory neuronal
system of PAG. At light microscopy, GABA-immunopositive (GABAIP) neurons formed two longitudinally oriented columns in the dorsolateral and ventrolateral PAG that accounted for 36% of the
neuronal population of both PAG columns; their perikaryal cross-sectional area was smaller than that of unlabeled (UNL) neurons
found in the same PAG subdivisions. At electron microscopic level, patches of GABA immunoreactivity were readily detected
in neuronal cell bodies, proximal and distal dendrites, axons and axon terminals. Approximately 35–36% of all terminals were
GABAIP; they established symmetric synapses with dendrites (84.72% of the sample in the dorsolateral PAG and 86.09% of the sample
in the ventrolateral PAG) or with cell bodies (7–10% of the sample). Moreover, 49.15% of GABAIP axon terminals in the dorsolateral and 52.16% in the ventrolateral PAG established symmetric synapses with GABAIP dendrites. Immunopositive axon terminals and unlabeled terminals were also involved in the formation of a complex synaptic
arrangment, i.e. clusters of synaptic terminals in close contact between them that were often observed in the PAG neuropil.
Moreover, a fair number of axo-axonic synapses between GABAIP and/or UNL axon terminals were present in both PAG subdivisions. Several dendro-dendritic synapses between labeled and unlabeled
dendrites were also observed in both PAG subdivisions. These results suggest that in the cat PAG there exist at least two
classes of GABArgic neurons. The first class could exert a tonic control on PAG projecting neurons, the second could act on
those GABAergic neurons that in turn keep PAG projecting neurons under tonic inhibition. The functional implications of this
type of GABAergic synapse organization are discussed in relation to the dishinibitory processes that take place in the PAG. 相似文献