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1.
Phonation threshold pressure (PTP) is the minimum subglottal pressure required to initiate vocal fold oscillation. Although potentially useful clinically, PTP is difficult to estimate noninvasively because of limitations to vocal motor control near the threshold of soft phonation. Previous investigators observed, for example, that trained subjects were unable to produce flat, consistent oral pressure peaks during/pae/syllable strings when they attempted to phonate as softly as possible (Verdolini-Marston, Titze, & Druker, 1990). The present study aimed to determine if nasal airflow or vowel context affected phonation threshold pressure as estimated from oral pressure (Smitheran & Hixon, 1981) in 5 untrained female speakers with normal velopharyngeal and voice function. Nasal airflow during /p/occlusion was observed for 3 of 5 participants when they attempted to phonate near threshold pressure. When the nose was occluded, nasal airflow was reduced or eliminated during /p/;however, individuals then evidenced compensatory changes in glottal adduction and/or respiratory effort that may be expected to alter PTP estimates. Results demonstrate the importance of monitoring nasal flow (or the flow zero point in undivided masks) when obtaining PTP measurements noninvasively. Results also highlight the need to pursue improved methods for noninvasive estimation of PTP. 相似文献
2.
MA Steller KJ Gurski M Murakami RW Daniel KV Shah E Celis A Sette EL Trimble RC Park FM Marincola 《Canadian Metallurgical Quarterly》1998,4(9):2103-2109
Human papillomavirus (HPV) infection has been causally associated with cervical cancer. We tested the effectiveness of an HLA-A*0201-restricted, HPV-16 E7 lipopeptide vaccine in eliciting cellular immune responses in vivo in women with refractory cervical cancer. In a nonrandomized Phase I clinical trial, 12 women expressing the HLA-A2 allele with refractory cervical or vaginal cancer were vaccinated with four E786-93 lipopeptide inoculations at 3-week intervals. HLA-A2 subtyping was also performed, and HPV typing was assessed on tumor specimens. Induction of epitope-specific CD8+ T-lymphocyte (CTL) responses was analyzed using peripheral blood leukapheresis specimens obtained before and after vaccination. CTL specificity was measured by IFN-gamma release assay using HLA-A*0201 matched target cells. Clinical responses were assessed by physical examination and radiographic images. All HLA-A*0201 patients were able to mount a cellular immune response to a control peptide. E786-93-specific CTLs were elicited in 4 of 10 evaluable HLA-A*0201 subjects before vaccination, 5 of 7 evaluable HLA-A*0201 patients after two vaccinations, and 2 of 3 evaluable HLA-A*0201 cultures after all four inoculations. Two of three evaluable patients' CTLs converted from unreactive to reactive after administration of all four inoculations. There were no clinical responses or treatment toxicities. The ability to generate specific cellular immune responses is retained in patients with advanced cervical cancer. Vaccination with a lipidated HPV peptide epitope appears capable of safely augmenting CTL reactivity. Although enhancements of cellular immune responses are needed to achieve therapeutic utility in advanced cervical cancer, this approach might prove useful in treating preinvasive disease. 相似文献
3.
The present investigation provide evidences from a non-human primate model that naturally occurring menopause predicts a prominent signature of age-related cognitive decline. Young and aged rhesus monkeys were tested on a delayed response (DR) task known to the sensitive to aging, and reproductive status was evaluated according to menstrual cyclicity and urinary hormone profiles. Peri-/postmenopausal monkeys exhibited significant DR impairments relative to either age-matched premenopausal females, or young control subjects. In addition, markers of endocrine decline in the aged animals were selectively correlated with behavioral performance measures that distinguished premenopausal and peri-/postmenopausal monkeys. These results document that menopause is coupled to cognitive decline in the monkey, and they establish a valuable primate model for defining the effects of endocrine aging on brain and behavioral function. 相似文献
4.
Y Sun A Hildesheim LA Brinton PC Nasca CL Trimble RJ Kurman RP Viscidi KV Shah 《Canadian Metallurgical Quarterly》1996,63(2):200-203
We describe a case of positional dyspnea due to compression of the tracheobronchial tree by an extensive thoracic aneurysm. In a 77-year-old woman with long-standing systemic hypertension, intermittent anterior chest pain gradually developed over several years. She had no history of asthma or thoracic trauma. She was admitted to our hospital because of sudden, severe shortness of breath. The breathlessness was markedly worse when she lay on her back or on her right side. On physical examination, she was in acute respiratory distress with cyanosis, severe hypertension (180/110 mmHg), tachycardia, and inspiratory stridor. A chest X-ray film showed loss of volume and nearly complete radiopacity of the left hemithorax. Arterial blood gas analysis revealed an arterial oxygen partial pressure of 54.8 mmHg, a carbon dioxide partial pressure of 39.8 mmHg, and an oxygen saturation of 84.5 percent on room air. Computed tomographic examination of the thorax showed dilation of the aortic arch and descending aorta, and marked compression of the trachea and the left main bronchus. Examination with a fiberoptic bronchoscope revealed extrinsic compression of the trachea just proximal to the carina. The patient's symptoms stabilized. However, she did not undergo surgery because of her age and because of the size of the aneurysm. She died due to rupture of the aneurysm. 相似文献
5.
KV Shah TD Kessis F Shah JW Gupta D Shibata RW Jones 《Canadian Metallurgical Quarterly》1996,15(2):127-130
Unstable expansion of the CTG repeats in the 3' untranslated region encoding a member of the protein kinase family in the q13.3 band on chromosome 19 is a mutation specific for myotonic dystrophy. To examine the correlation between clinical expression and CTG trinucleotide repeat length, we carried out Southern blot analysis in a family with myotonic dystrophy. In this pedigree, the expanded CTG repeats were transmitted maternally. The mother had three female children. The mother had about 200 CTG repeats, and the number of repeats for each child was about 800, 1500 and 1600 in birth order. The mother and the patient with 800 repeats were unaware of muscle weakness or myotonia. Symptoms were present from age 3 years in the patient with 1500 repeats and from birth in the one with 1600 repeats. Although the mother menstruated regularly, the patients with 800 and 1500 repeats both menstruated irregularly, and the one with 1600 repeats has never menstruated. The age of onset and severity of the disease were correlated with the size of the expanded repeats. Endocrinological studies revealed that the basal levels of the gonadotropins, PRL and E2 were within normal range, and a pituitary response to LHRH was observed. These data suggest that the amenorrhea and menstrual irregularities were caused by a suprahypophyseal dysfunction. When expanded CTG repeats are transmitted maternally, abnormal products resulting from the metabolic disturbance in the affected mother may harm the fetus in utero. A heterozygous fetus, who has more CTG repeats, may be unable to metabolize the pathologic products sufficiently and therefore may become more severely affected. This may explain the exclusive maternal transmission of congenital myotonic dystrophy. 相似文献
6.
G Stoll S Müller B Schmidt P van der Meide S Jung KV Toyka HP Hartung 《Canadian Metallurgical Quarterly》1993,142(6):1866-1875
This study reports the cellular localization of interferon-gamma (IFN-gamma) and MHC class II antigen (Ia) in the spinal cord of rats with experimental autoimmune encephalomyelitis induced by adoptive transfer of myelin basic protein-specific T cells. Numerous IFN-gamma-positive cells, stained with two different monoclonal antibodies against IFN-gamma, were present from days 3 to 7 after cell transfer. Their number was greatly reduced on day 10. A subpopulation of T cells was IFN-gamma positive. Moreover, a large number of ED1-positive macrophages contained IFN-gamma immunoreactivity. The transient presence of immune cells containing IFN-gamma immunoreactivity in experimental autoimmune encephalomyelitis suggests a pathogenic role of this cytokine in immune-mediated demyelination of the central nervous system. 相似文献
7.
The use of the transjugular intrahepatic portosystemic shunt to treat portal hypertension has resulted in increased recognition of its associated complications. We report a patient with refractory duodenal variceal bleeding treated with transjugular intrahepatic portosystemic shunt, as well as coil embolization, who subsequently developed bilateral cerebral and cerebellar infarcts consistent with arterial emboli. This complication has not been previously described. The patient was found to have a patent foramen ovale and a right to left intracardiac shunt leading to paradoxical embolization of clots traveling from portal to systemic venous circulation, then to the left atrium. With the relative frequency of patent foramen ovale in the population, our observation has potential importance for patients with right to left cardiac shunts who are being considered for portosystemic shunt procedures, or who are undergoing embolization of bleeding varices. 相似文献
8.
The objective of this study is to analyze volatile organic compound (VOC) concentrations in Taiwan's drinking water supply. Focusing on Taiwan's three major metropolitan areas--Taipei, Taichung and Kaohsiung (in the north, middle and south, respectively)--171 samples were taken from tap water and 68 from boiled water. Tests showed VOC concentrations were highest in Kaohsiung. This is due to different water sources and methods of treatment. Except for bromoform, trihalomethane (THM) concentrations were highest. Detection rates of toluene and 1,2-dichloroethane were slightly higher than other VOC compounds. VOC concentrations decreased significantly after water was boiled. THMs had a removal rate from 61% to 82%. The authors conclude that the three metropolitan areas contain significantly different levels of VOCs and that boiling can significantly reduce the presence of VOCs. Other sources of pollution that contaminate drinking water such as industrial plants and gas stations must be further investigated. 相似文献
9.
In male Syrian hamsters, short days induce regression of the reproductive system, but eventually spontaneous recrudescence occurs ensuing from refractoriness to the inhibitory photoperiod. Although the photoperiod of 12 L:12 D (12 h light:12 h dark) may act like a short day by inducing the testicular cycle outlined above, it may fail to evoke the increase of circulating concentrations of prolactin that accompanies testicular recrudescence. This photoperiod may fail to induce photorefractoriness, as indicated by the prolonged low concentrations of prolactin in the blood. Herein, hamsters were exposed to either 8 L:16 D or 12 L:12 D from weaning and by 28 weeks exposure to either photoperiod, the hamsters had large testes following recrudescence from a photoperiod induced-regression). Transfer to 8 L:16 D from 12 L:12 D at 28 weeks resulted in a second testicular regression and recrudescence. In a second experiment, the testes of hamsters moved to 8 L:16 D from 12 L:12 D after 29 weeks exposure to the latter photoperiod similarly regressed and then regrew. Serum concentrations of prolactin decreased in these males after transfer to the shorter daylength but also decreased in hamsters kept under 12 L:12 D both groups were usually below those of hamsters moved to 14 L:10 D. These results show that exposure for 28 or 29 weeks to 12 L:12 D was insufficient to induce photorefractoriness, despite the recrudescence of the testes following involution. 相似文献
10.
GS Alarcón J Roseman AA Bartolucci AW Friedman JM Moulds N Goel KV Straaton JD Reveille 《Canadian Metallurgical Quarterly》1998,41(7):1173-1180
OBJECTIVE: To determine the factors associated with disease activity in patients with recent-onset (< or =5 years) systemic lupus erythematosus (SLE) who were of Hispanic, African-American, or Caucasian ethnicity. METHODS: Incident and prevalent cases of SLE, as defined by the American College of Rheumatology criteria for SLE, among the 3 ethnic groups were identified in Alabama (The University of Alabama at Birmingham) and Texas (The University of Texas-Houston Health Science Center and The University of Texas Medical Branch at Galveston). Variables from the sociodemographic, clinical, immunologic, immunogenetic, behavioral, and psychological domains were obtained using validated instruments. Disease activity was ascertained with the Systemic Lupus Activity Measure (SLAM). Stepwise domain regressions with SLAM score as the dependent variable were performed. Final ethnic-specific and overall regression models were obtained by entering variables that were retained in the domain regressions. RESULTS: SLAM scores at study entry were higher in the African Americans (mean +/- SD 12.6 +/- 6.9) and Hispanics (11.0 +/- 6.2) than in the Caucasians (8.5 +/- 3.7) (P < or = 0.001). The final overall regression model (R2 = 28%) for higher SLAM score included the following variables: African-American ethnicity, lack of private health insurance, abrupt disease onset, presence of anti-Ro antibodies, absence of HLA-DRB1*0301, higher levels of helplessness, and abnormal illness-related behaviors. CONCLUSION: Socioeconomic, immunologic, immunogenetic, behavioral, and psychological variables were all predictive of disease activity early in the course of SLE, irrespective of ethnic group. However, there remain ethnic group differences in disease activity that were not explained by these factors. 相似文献