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At least 1,153 records · Page 64Linked to original sources
PubMed1990

Experience with the functional cleft lip repair.

The first 12 functional cleft lip repairs performed on unselected consecutive patients immediately following the completion of training by the author are presented. Previous reports on this cleft lip repair have shown excellent results but have always been based on patients operated on by the originator of the procedure. This report gives credence to the ease with which a cleft lip repair that gives reproducible good results can be taught and learned even by plastic surgeons with limited experience. It reviews the technical steps of the procedure, which emphasizes wide undermining and release of the orbicularis oris muscle on the lateral side of the cleft to allow redraping and lengthening of the lip skin, step-by-step layered closure of the mucosa, muscle, and skin, and further vertical lengthening of the lip with a Z-plasty skin closure. Three elements that are difficult to achieve or restore with cleft lip revision are evaluated: (1) achievement of a good skin scar, (2) maintenance of the alar-facial groove, and (3) achievement of adequate lip height without sacrificing horizontal lip length. Ten of the 12 patients had a satisfactory scar, 9 patients had a good alar-facial groove, and all patients had a normal-appearing horizontal lip length. Nine patients required secondary surgery; however, in six patients, this included correction of the nasal deformity that was not corrected at the time of cleft lip repair.

Child, Preschool↗
PubMed1985

The addiction experience as a function of the addict's history.

Application of personal construct theory to addicts in treatment led to a series of hypotheses about their psychological reactions and how these might differ with differences in their histories. Their scores on a set of content analysis scales were compared with those of a relatively non-stressed group and a relatively stressed group matched for sex and age. The chief element in the pattern of experiential elements which was identified was uncertainty. Addicts also expressed more anxiety, depression and anger (directly and indirectly) and reported fewer social interactions than the non-stressed group; however, for most of these elements they were similar to the similarly stressed group of young people with whom they were compared. The pattern of experience of addiction was found to vary according to the employment, addiction and criminal histories of the addicts, their treatment histories as represented by their counsellors' assessments of them and the social supports available to them.

Adolescent↗
PubMed1977

[Studies on the effect of urapidil on the central nervous system and various organ functions in animal experiments (author's transl)].

Compared to the changes in spontaneous behaviour of mice and rats, 6-(3-[4-(o-methoxyphenyl)-1-piperazinyl]-propyl-amino)-1,3-dimethyluracil (urapidil, Ebrantil) in doses from 10 mg/kg p.o. has a central sedative action, for which it is typical that it can be interrupted by external stimuli after doses of up to approx. 100 mg/kg. By this action urapidil differs from other central-acting drugs, e.g. chlor-promazine, diazepam and clonidine. It can be assumed that urapidil has no central dopamine blocking qualities because it does neither influence the conditioned avoidance response nor the amphetamine-induced gnawing of the rat. Urapidil is also different from diazepam bacause it does not hinder spinal polysynaptic motor reflexes of the decerebrated cat. Up to 80 mg/kg p.o. of urapidil, there was no hypotensive effect in the rat to be seen and, therefore, it can be concluded that changes in spontaneous and reactive behaviour are not due to acute changes in cardiovascular functions. The antihistamine effect of urapidil in the isolated ileum of the guinea pig is approx. 15 times weaker than that of chlorpromazine, furthermore urapidil has no anticholinergic quality.

Animals↗
PubMed2003

Quantifying generalization from trial-by-trial behavior of adaptive systems that learn with basis functions: theory and experiments in human motor control.

During reaching movements, the brain's internal models map desired limb motion into predicted forces. When the forces in the task change, these models adapt. Adaptation is guided by generalization: errors in one movement influence prediction in other types of movement. If the mapping is accomplished with population coding, combining basis elements that encode different regions of movement space, then generalization can reveal the encoding of the basis elements. We present a theory that relates encoding to generalization using trial-by-trial changes in behavior during adaptation. We consider adaptation during reaching movements in various velocity-dependent force fields and quantify how errors generalize across direction. We find that the measurement of error is critical to the theory. A typical assumption in motor control is that error is the difference between a current trajectory and a desired trajectory (DJ) that does not change during adaptation. Under this assumption, in all force fields that we examined, including one in which force randomly changes from trial to trial, we found a bimodal generalization pattern, perhaps reflecting basis elements that encode direction bimodally. If the DJ was allowed to vary, bimodality was reduced or eliminated, but the generalization function accounted for nearly twice as much variance. We suggest, therefore, that basis elements representing the internal model of dynamics are sensitive to limb velocity with bimodal tuning; however, it is also possible that during adaptation the error metric itself adapts, which affects the implied shape of the basis elements.

Adaptation, Physiological↗
PubMed2002

[EndNote 5 reference manager--functions--improvements--personal experiences].

Bibliography database managers are used to manage information recourses: specifically, to maintain a database to references and create bibliographies and reference lists for written works. A good reference management program should make it easy to read and to record the elements that a reference comprises, e.g. authors name, year of publication, title of article etc. It should offer tools that let you find and retrieve references quickly, and it should be able to produce the bibliography in the format required for a particular publication. You can create your database reference by reference or you can download batches of references from one of the popular searching services (e.g. MEDLINE) and you can search in the Internet. When you want to cite a reference you simply paste the reference wherever you want your intext citation to appear. There are many computer programs, but very few stands out as truly useful, time saving, and work enhancing. One of them is EndNote. The reference manager EndNote 5.0 was recently released in Germany. As long-time fans of this excellent program, we upgraded from the previous version. The use of the software package EndNote 5.0 for Windows is described. The main reason for getting EndNote 5.0 is its clearly improved functions and features: especially the co-operation with Microsoft Word (cite while you write) and the spelling examination. Altogether EndNote 5.0 provides also an excellent combination of features and ease of use.

Database Management Systems↗
PubMedDate not supplied

[The function of the liver mono-oxygenase system in a non-coronarogenic lesion of the heart muscle in an experiment].

The functional state was studied of the monooxygenase system in the liver in the time-related progression of izardine-induced myocarditis (IM) and allergic myocarditis (AM) in rats. In IM, the activity of monooxygenase enzymes (ME) was found to have gotten increased against the background of a decrease in the content of microsomal cytochromes, which event is believed to be secondary to a direct effect of izardine on the liver. In AM, a decline in ME activity appeared to correlate with a decrease in the content of microsomal cytochromes. This suggests a direct impact of cardiac pathology on the liver.

Analysis of Variance↗
PubMed1998

The effect of surgeon experience on velopharyngeal functional outcome following palatoplasty: is there a learning curve?

There is little information in the cleft palate literature concerning the relationship between surgeon volume and clinical outcomes. It is unknown whether such a relationship applies specifically to velopharyngeal dysfunction and the need for secondary physical management of the velopharynx. The purpose of this paper was to explore the concept of an operative learning curve for different surgeons with respect to palatoplasty. Impact of case volume and procedure type on the occurrence of secondary palatal management (the main outcome measure) was assessed. The charts of 472 consecutive palatoplasty patients were reviewed by one speech and language pathologist to determine when the palatoplasty was performed, which surgeon (n = 9) performed the palatoplasty, whether velopharyngeal status was documented at a minimum of 6 years of age, and whether secondary palatal management was prescribed. The results were analyzed by year of palatoplasty, by surgeon, and by number of operations per surgeon to determine total and individual surgeon rates of secondary palatal management. There were 401 palatoplasties (85 percent recovery) with adequate documentation of velopharyngeal status by at least 6 years of age. Palatoplasty rates ranged between 1 and 258 palatoplasties per surgeon. Over the 12 years reviewed, secondary palatal management was performed for 92 patients (23 percent) of the study population. Examination of the proportion of palatoplasty patients receiving secondary palatal management by surgeon and by year showed only one surgeon with a pattern suggesting a learning curve. The proportion of patients receiving secondary palatal management was plotted against the total number of surgeries the surgeon performed. There was a strong relationship between experience and success. The number of procedures this surgeon performed per year increased at approximately the same time as the success rate improved. The categories of "total procedures" and "procedure per year" were highly correlated with each other. Success rates were analyzed by number of procedures performed per year, and there was a clear association between the two variables. To separate the effect of the two variables, a multiple regression model was constructed. The category of "total procedures" was statistically significant in the model, whereas procedures per year was not, suggesting that the key to the dominant surgeon's improvement was cumulative experience rather than frequency of performance of the operation. Palatoplasties performed by high-volume surgeons are more likely to result in better postoperative outcomes (i.e., lower rates of secondary palatal management) as compared with palatoplasties performed by low-volume surgeons. The influence of the surgeon's cumulative experience on improvement seems to be more important than the frequency of performance of primary palatoplasty.

Cleft Palate↗
PubMed1998

Independent coupling of the human tachykinin NK2 receptor to phospholipases C and A2 in transfected Chinese hamster ovary cells.

The human tachykinin NK2 receptor stably expressed in Chinese hamster ovary cells (CHO-hNK2R cells) was characterized by studying the effect of neurokinin A (NKA), the preferred natural ligand, and that of other agonists and antagonists in both binding experiments and functional assays. Competition experiments using [125I]NKA showed that CHO-hNK2R cells express binding sites which have high affinity for NKA (Ki=3.4+/-0.9 nM), GR 64349 (Ki=12+/-3 nM) and [betaAla8]NKA(4-10) (Ki=21+/-8 nM) and for the antagonists MEN 10627 (Ki=0.55+/-0.2 nM), and MEN 11420 (Ki=2.4+/-0.8 nM). In contrast, the tachykinin NK1 and NK3 receptor agonists [Sar9,Met(O2)11]SP and senktide, respectively, were recognized with low affinity (Ki>10 microM). NKA (EC50=68+/-18 nM) induced a rapid and concentration-dependent increase in the intracellular level of inositoltrisphosphate (IP3). The concentration-response curve to GR 64349 (EC50=155+/-14 nM) was close to that of NKA, whereas [betaAla8]NKA(4-10) (EC50=445+/-78 nM) and SP (EC50=3197+/-669 nM) were 7- and 50-fold less potent, respectively. In addition, NKA stimulated the release of arachidonic acid and the production of prostaglandin E2 (PGE2) in a concentration-dependent manner. Also in this assay, NKA was found to be more potent than the other agonists tested (the EC50 values were 3+/-0.3, 9+/-3, 7.8+/-0.9 and 217+/-37 nM for NKA, GR 64349, [betaAla8]NKA(4-10) and SP, respectively). MEN 10627 and MEN 11420 were potent and competitive antagonists in blocking NKA-induced IP3 formation and PGE2 release: MEN 10627 and MEN 11420 displayed comparable potencies in blocking the two functional responses initiated by occupancy of the NK2 receptor by NKA. Pretreatment of the cells with pertussis toxin (500 ng/ml for 18 h) did not significantly modify the basal or stimulated phosphatidylinositol turnover but reduced the basal and NKA-induced PGE2 release by about 35%. The phospholipase C inhibitor U-73122 (10 microM) prevented the NKA-induced formation of IP3 but did not affect PGE2 release. Conversely, the phospholipase A2 inhibitor quinacrine (100 microM) blocked the release of arachidonic acid and PGE2 without affecting the NKA-stimulated formation of IP3. Chelation of extracellular calcium with 3 mM EGTA inhibited the NKA-induced PGE2 release by 81% but was without effect on basal and NKA-stimulated IP3 production. The calcium channel blockers verapamil (10 microM) and omega-conotoxin GVIA (0.1 microM) did not modify the basal PGE2 production and had no significant effect on the response to tachykinins while the blocker of non-selective cation channels, SKF-96365 (10 microM), inhibited the response to NKA by about 74%. SKF-96365 did not affect the basal or the NKA-induced IP3 formation. In conclusion, our data demonstrate that the human tachykinin NK2 receptor expressed in CHO cells displays binding affinity and functional properties which are those of a native NK2 receptor. No pharmacological evidence for heterogeneity of the human NK2 receptor was obtained in this study. Our findings indicate that the human tachykinin NK2 receptor is independently coupled to both PLC and PLA2 signaling pathways. Activation of the PLA2 pathway may be linked to the opening of a voltage-independent cation channel which activates a Ca2+-dependent PLA2.

Animals↗
PubMed2000

Crossed-beam study of Co+(3F4)+propane: experiment and density functional theory

A pulsed beam of Co+(3F4) crosses a pulsed beam of C3H8 or C3D8 gas under single collision conditions at collision energies of 0.01 eV and 0.21 eV. After a variable time delay t(ext) = 1-8 micros a fast high voltage pulse extracts product ions into a field-free flight tube for mass analysis. Consistent with earlier work, we observe prompt CoC3H6+ +H2 elimination products in 3:1 excess over CoC2H4+ +CH4 products at 0.21 eV on a 2-10 micros time scale. Long-lived CoC3H8+ complexes fragment predominantly back to Co+ +C3H8 reactants and to H2 elimination products on a 6-24 micros time scale. Density functional theory (B3LYP) calculations provide energies, geometries, and harmonic vibrational frequencies at key stationary points for use in a statistical rate model of the reaction. By adjusting two key multicenter transition state (MCTS) energies downward by 4-7 kcal mol(-1), we obtain good agreement with our decay time results and with the cross section versus collision energy of Armentrout and co-workers from 0.1-1.0 eV. B3LYP theory succeeds in finding relative energies of the MCTSs leading to CH4 and H2 in the proper order to explain the different product branching ratio for Co+ (which favors H2 over CH4) compared with its nearest neighbors Fe+ and Ni+ (which favor CH4 over H2).

Journal Article↗
PubMed2006

The value of onsite adequacy assessment of thyroid fine-needle aspirations is a function of operator experience.

BACKGROUND: Cytotechnologists and pathologists often perform onsite evaluations of thyroid fine-needle aspirations (FNAs) to provide immediate feedback regarding whether adequate material has been obtained for cytologic diagnosis. The current study was designed to determine whether onsite adequacy assessment results in a significant decrease in nondiagnostic specimens between ultrasound (US)-guided FNAs of the thyroid and those performed by palpation alone. METHODS: A search was performed to identify in-house thyroid FNAs performed between January 1, 2000 and December 31, 2003 that were obtained under US guidance or by palpation only. It was then recorded whether an onsite adequacy assessment was performed. The submitting physician and final diagnosis also were recorded for each case. Contingency tables were constructed and evaluated using chi-square analysis. RESULTS: Of 1502 in-house thyroid FNAs included in the current study, 981 (65.3%) were performed under US guidance and 521 (34.7%) were performed with palpation alone. Onsite adequacy assessment of the aspirated material was performed in 323 cases (21.5%), whereas 1179 cases (78.5%) were performed without onsite evaluation. Of the 418 palpation-guided FNAs that were performed without adequacy assessment, 70 (16.7%) were reported to be nondiagnostic, whereas of the 103 palpation-guided FNAs with immediate evaluation, only 7 (6.8%) were determined to be inadequate for diagnosis. This difference was statistically significant (P < 0.025). Of 761 US-guided FNAs without immediate adequacy assessment, 54 (7.1%) were nondiagnostic, which was not statistically different from the nondiagnostic rate of 4.5% (10 of 220 cases) for US-guided FNAs with onsite evaluation. However, when these US-guided FNAs were divided further into 2 groups based on the experience of the radiologist performing the FNA, the nondiagnostic rate in the group of experienced radiologists was only 5.4% (or 32 of 592 US-guided FNAs), even though onsite evaluation was not performed. Among radiologists with less experience, adequacy assessment significantly reduced the nondiagnostic rate from 13.0% (22 of 169 FNAs without adequacy assessment) to 4.5% (10 of 220 FNAs with adequacy assessment) (P < 0.01). CONCLUSIONS: The results of the current study demonstrate that onsite adequacy assessment of thyroid FNAs significantly reduces the number of nondiagnostic aspirates. However, the benefit of onsite evaluation, at least for US-guided FNAs, depends on the experience of the radiologist. In the current study, experienced radiologists with a relatively low nondiagnostic rate did not benefit from onsite adequacy assessment. This finding confirms the importance of experience in the performance of FNA, but suggests that onsite adequacy assessment may assist the less experienced operator.

Biopsy, Fine-Needle↗
PubMed2000

Evidence for differential signaling in human conjunctival epithelial cells adherent to laminin isoforms.

Both the laminin composition of the basement membrane and the keratin intermediate filament composition of the epithelial cell differs between cornea and conjunctiva, suggesting that at least some aspects of ocular surface epithelial cell differentiation may be regulated by extracellular matrix. The purpose of this study was to analyse the role of beta1 integrin in intracellular signaling pathways in human conjunctival epithelial cells adherent to laminin. In addition, the purpose was to compare the phosphorylation kinetics of signaling intermediates in cells adherent to different laminin isoforms. Cell adhesion assays, integrin clustering experiments, and integrin function blocking experiments demonstrated that beta1 but not beta4 integrin mediated human conjunctival epithelial cell adhesion to placental laminin isoforms (laminin-10/11) and induced focal adhesion kinase (FAK) tyrosine phosphorylation. Western blot analysis of cell lysates adherent to placental laminin showed that the tyrosine phosphorylation of p130Cas and FAK was maximally above constitutive levels after 60 min. In cells adherent to EHS laminin (laminin-1), the tyrosine phosphorylation kinetics of tensin, p130Cas, FAK and unknown proteins of 138 kDa and 110 kDa were similar, and peaked above constitutive levels after 30 min. Tyrosine phosphorylation of a 70 kDa protein was induced by cell adhesion to EHS laminin after 5 min, and phosphorylation peaked at 15 min. In contrast, the tyrosine phosphorylation of the 70 kDa protein was undetected in cells adherent to placental laminin. Erk-1 phosphorylation and activation was not differentially modulated by conjunctival epithelial cell adhesion to laminins. However, phosphorylation and activation kinetics of Erk-2 in cells adherent to placental laminin was similar to that observed for FAK and p130Cas. Erk-2 phosphorylation and activation was essentially undetectable in cells adherent to EHS laminin. These observations suggest that human conjunctival epithelial cell adhesion to different laminin isoforms activates different intracellular signaling pathways, and provides support for the hypothesis that extracellular matrix molecules can modulate ocular surface epithelial cell differentiation via alternate signaling pathways.

Antibodies, Monoclonal↗