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11.
Sandra L. Harris Sharlene A. Wolchik Steven Weitz 《Journal of autism and developmental disorders》1982,11(4):373-384
The mothers and fathers of 11 preschool autistic children were taught operant procedures used in teaching speech to nonverbal children. The children's speech skills were assessed twice before and once after their parents were trained. At posttreatment, the children showed significant gains in prespeech and speech skills as measured by a 21-step hierarchy of speech behaviors. Those children who had acquired at least verbal imitative skill after training made greater progress than those who had not. Although children maintained their gains in a 1-year follow-up assessment, there was no evidence of significant improvement beyond that achieved at the end of training. The importance of support for parents in continuing to do formal teaching after the training program ends was stressed.Support for this research came in part from a grant from the National Institute of Mental Health (MH 29897-04) to the first author. Our thanks to Elayne Weitz, who co-led one of the groups, to Beverly Brysk for data processing, and to Rona Milch for statistical consultation. 相似文献
12.
Arterial and venous thrombosis are a major cause of morbidity and mortality. Anticoagulants are a cornerstone of treatment in patients with these disorders. The two most frequently used anticoagulants, heparin and warfarin, have pharmacological and/or biophysical limitations that make them difficult to use in day-to-day clinical practice. Development of new anticoagulants, which were designed to overcome these limitations, has been facilitated by an increased understanding of the coagulation cascade, the advent of molecular modeling and structure-based drug design, and the realization that the treatment of thrombosis and its complications consumes billions of dollars in annual healthcare expenditures. New anticoagulants target various steps in the coagulation pathway. Coagulation is triggered by the factor VIIa/tissue factor complex and propagated by factors Xa and IXa, together with their activated cofactors, factor Va and VIIIa, respectively. Thrombin, the final effector in coagulation, then converts soluble fibrinogen into insoluble fibrin, the major matrix protein of the clot. New anticoagulation drugs that target each of these clotting enzymes have been developed. This review will focus on those drugs in more advanced stages of clinical evaluation. These include inhibitors of initiation of coagulation (tissue factor pathway inhibitor, nematode anticoagulant peptide and active-site blocked factor VIIa), inhibitors of propagation of coagulation (active-site blocked factor IXa, antibodies against factor IX/IXa, fondaparinux sodium, direct factor Xa inhibitors, protein C derivatives and soluble thrombomodulin), and thrombin inhibitors (hirudin, bivalirudin, argatroban and ximelagatran). 相似文献
13.
A Shuper G Horev L Kornreich S Michowiz R Weitz R Zaizov I Cohen 《Archives of disease in childhood》1997,76(3):259-263
Accepted 12 September 1996
OBJECTIVE—Our experience in children with visual pathway glioma (VPG) was reviewed to delineate its clinical characteristics.
DESIGN—The charts and imaging studies of 21 children with VPG who were followed up in our centre during the last 12 years were reviewed and summarised.
RESULTS—VPG accounted for 13.1% of all brain tumours treated during this period. Sixty two per cent of the children with VPG had neurofibromatosis type 1 (NF-1). Among these, more than 60% were detected as part of routine work up. In some cases decreasing visual function preceded the appearance of the VPG on imaging studies. Tumour growth rate was markedly unpredictable. All treatment modalities employed led to tumour shrinkage and stabilisation for a variable period, but none was successful in totally eradicating the tumour. Complications were less severe after chemotherapy compared with radiotherapy. Three children died, none with NF-1, with a globular hypothalamic/chiasmatic tumour and accompanying electrolyte abnormalities.
CONCLUSIONS—NF-1 is a favourable prognostic marker for VPG. Whenever possible a period of observation is necessary before treatment is initiated, during which time tumour size and visual function should be closely followed up; an untoward change in either of these is an indication for the start of treatment, preferably chemotherapy first. The combination of a globular hypothalamic/chiasmatic glioma and electrolyte abnormalities in a child without NF-1 are related to a poor prognosis.
相似文献
OBJECTIVE—Our experience in children with visual pathway glioma (VPG) was reviewed to delineate its clinical characteristics.
DESIGN—The charts and imaging studies of 21 children with VPG who were followed up in our centre during the last 12 years were reviewed and summarised.
RESULTS—VPG accounted for 13.1% of all brain tumours treated during this period. Sixty two per cent of the children with VPG had neurofibromatosis type 1 (NF-1). Among these, more than 60% were detected as part of routine work up. In some cases decreasing visual function preceded the appearance of the VPG on imaging studies. Tumour growth rate was markedly unpredictable. All treatment modalities employed led to tumour shrinkage and stabilisation for a variable period, but none was successful in totally eradicating the tumour. Complications were less severe after chemotherapy compared with radiotherapy. Three children died, none with NF-1, with a globular hypothalamic/chiasmatic tumour and accompanying electrolyte abnormalities.
CONCLUSIONS—NF-1 is a favourable prognostic marker for VPG. Whenever possible a period of observation is necessary before treatment is initiated, during which time tumour size and visual function should be closely followed up; an untoward change in either of these is an indication for the start of treatment, preferably chemotherapy first. The combination of a globular hypothalamic/chiasmatic glioma and electrolyte abnormalities in a child without NF-1 are related to a poor prognosis.
相似文献
14.
James Paul Dworkin Robert J. Meleca Michelle M. Zormeier Mark L. Simpson Ilene Garfield Ma John R. Jacobs Robert H. Mathog 《The Laryngoscope》1998,108(12):1773-1781
Objectives: The reconstructed pharyngoesophageal segment (PES) serves as the neoglottis following total laryngectomy, as it provides the source of vibration for production of tracheoesophageal puncture (TEP) voice. To date, little information exists regarding the vibratory characteristics of the PES. The purpose of this investigation was to study the anatomy and physiology of the PES using videostroboscopy. Study Design: Prospective study investigating the anatomy and physiology of the PES in 34 laryngectomees who used TEP speech as their primary form of communication. Materials and Methods: Videostroboscopy and voice recordings were graded by three trained, blinded judges using a seven-point scale. Results: The patients demonstrated differences that allowed for separation of patients into two main groups: “poor” and “effective” TEP speakers. The voice quality differences were explained by anatomic and physiologic characteristics of the PES. Redundant, thick, and dyssynchronous PES features were observed in patients with poor TEP speech skills; the effective speakers exhibited less redundant, thinner mucosa and more synchronous vibratory patterns. Moreover, the latter subgroup consistently demonstrated a greater degree of volitional PES control and less spasmodic activity than their poorly speaking counterparts. Length of the PES opening (measured in the horizontal plane) as well as amount and consistency of secretions did not appear to influence TEP speech or voice proficiency. Conclusion: Videostroboscopy in laryngectomees is a noninvasive, inexpensive, easily performed procedure that may contribute valuable information regarding the anatomy and physiology of the PES, especially in patients who experience difficulties achieving satisfactory TEP voice and speech production. 相似文献
15.
16.
Colocalization of the tetraspanins, CO-029 and CD151, with integrins in human pancreatic adenocarcinoma: impact on cell motility. 总被引:6,自引:0,他引:6
Sabine Gesierich Claudia Paret Dagmar Hildebrand Jürgen Weitz Kaspar Zgraggen Friedrich H Schmitz-Winnenthal Vaclav Horejsi Osamu Yoshie Dorothee Herlyn Leonie K Ashman Margot Z?ller 《Clinical cancer research》2005,11(8):2840-2852
PURPOSE: Patients with pancreatic adenocarcinoma have a poor prognosis due to the extraordinary high invasive capacity of this tumor. Altered integrin and tetraspanin expression is suggested to be an important factor. We recently reported that after protein kinase C activation, colocalization of alpha6beta4 with the tetraspanin CO-029 strongly supports migration of a rat pancreatic adenocarcinoma. The finding led us to explore whether and which integrin-tetraspanin complexes influence the motility of human pancreatic tumors. EXPERIMENTAL DESIGN: Integrin and tetraspanin expression of pancreatic and colorectal adenocarcinoma was evaluated with emphasis on colocalization and the impact of integrin-tetraspanin associations on tumor cell motility. RESULTS: The majority of pancreatic and colorectal tumors expressed the alpha2, alpha3, alpha6, beta1, and beta4 integrins and the tetraspanins CD9, CD63, CD81, CD151, and CO-029. Expression of alpha6beta4 and CO-029 was restricted to tumor cells, whereas alpha1, alpha2, alpha3, alpha6, beta1, and CD9, CD81, CD151 were also expressed by the surrounding stroma. CD63, CD81, and beta1 expression was observed at comparably high levels in healthy pancreatic tissue. alpha3beta1 frequently colocalized and coimmunoprecipitated with CD9, CD81, and CD151, whereas alpha6beta4 colocalized and coimmunoprecipitated mostly with CD151 and CO-029. Notably, protein kinase C activation strengthened only the colocalization of CD151 and CO-029 with beta4 and was accompanied by internalization of the integrin-tetraspanin complex, decreased laminin 5 adhesion, and increased cell migration. CONCLUSION: alpha6beta4 is selectively up-regulated in pancreatic and colorectal cancer. The association of alpha6beta4 with CD151 and CO-029 correlates with increased tumor cell motility. 相似文献
17.
Karla D. Thrall Ronald E. Schwartz Karl K. Weitz Jolen J. Soelberg Gary L. Foureman James D. Prah 《Inhalation toxicology》2013,25(6):523-538
Nasal dosimetry models have become increasingly quantitative as insights into tissue deposition/clearance and computational fluid dynamics have become available. Validation of these models requires sufficient experimental data. However, investigations into respiratory deposition, particularly in human volunteers, have been historically limited due to methodological limitations. To overcome this, a method for evaluating the nasal wash-in, wash-out phenomena of a highly water-soluble compound in human volunteers was developed and characterized. This methodology was assessed using controlled human inhalation exposures to uniformly labeled [13 C]acetone at approximately 1 ppm concentration for 30 min under different breathing maneuvers (inhale nose/exhale nose; inhale nose/exhale mouth; inhale mouth/exhale nose). A small-diameter air-sampling probe inserted in the nasopharyngeal cavity of the volunteer was connected directly to an ion-trap mass spectrometer capable of sampling every 0.8 s. A second ion-trap mass spectrometer simultaneously sampled from the volunteer's exhaled breath stream via a breath-inlet device interface. Together, the two mass spectrometers provided real-time appraisal of the [13 C]acetone concentrations in the nasopharyngeal region and in the exhaled breath stream before, during, and after the different breathing maneuvers. The breathing cycle (depth and frequency) and heart rate were concurrently monitored throughout the exposure using a heart-rate monitor and a human plethysmograph to differentiate inhalation and exhalation. Graphical overlay of the plethysmography results with the mass spectrometer measurements show clear quantifiable differences in [13 C]acetone levels at the nasal probe as a function of breathing maneuvers. Breath-by-breath analyses of [13 C]acetone concentrations indicate that between 40 and 75% of the compound is absorbed upon inhalation and nearly all of that absorbed is released back into the breath stream during exhalation. 相似文献
18.
19.
Purpose: The aim of this study was to examine the feasibility of using nanoparticle-enhanced transmission ultrasound (NETUS) as an image-based monitoring modality for microwave hyperthermia treatment.Methods: A dedicated transmission ultrasound imaging system was used to obtain acoustic projections and ultrasound computed tomography images. Initially, speed-of-sound based images were used to non-invasively monitor temperature changes in in vitro and ex vivo specimens, induced by a microwave needle-type applicator. Next, the hyperthermia acceleration ability of two ultrasound nanoparticles based contrast agents (iron oxide and copper oxide) was examined and visualised. Finally, a two-step image guided microwave therapeutic procedure using NETUS was investigated in a realistic breast mimicking phantom. First, the pathology simulating region borders were detected. Then, a microwave-induced temperature elevation was non-invasively monitored.Results: The transmission ultrasound scanning system was able to detect temperature changes with a resolution of less than 0.5?°C, both in vitro and ex vivo. In accordance with previous studies, it was visually demonstrated that iron oxide nanoparticles expedite the heating process (p?0.05). Copper oxide nanoparticles, however, did not alter the hyperthermia profile significantly. In the breast mimicking phantom, NETUS yielded accurate detection of the target region as well as thermal monitoring of the microwave heating procedure.Conclusions: NETUS can combine enhanced target visualisation with non-invasive thermometry and accelerated heating effect. Quantitative feedback, however, requires a tissue-specific calibration-curve. A proof of concept for microwave hyperthermia treatment monitoring using NETUS was established. The suggested methodology may potentially provide a non-invasive cost-effective means for monitoring thermal treatment of the breast. 相似文献
20.
Elise C. Janicke M.D. Michael R. Nazareth M.D. Ph.D. Ilene L. Rothman M.D. 《Pediatric dermatology》2014,31(6):731-733
We report a patient with generalized smooth muscle hamartoma who presented with many of the variety of congenital anomalies that have been reported in babies with multiple symmetric circumferential rings of folded skin known as Michelin tire baby (MTB) syndrome, but our patient did not show the MTB phenotype. This constellation of findings in the absence of the MTB phenotype has not been previously reported. 相似文献