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1.
Nasal mucociliary clearance was measured in both healthy subjects and patients with chronic sinusitis using saccharin granule technique. Nasal mucociliary transit time (ST) was significantly slower in the patients with chronic sinusitis compared with that in controls (p less than 0.005). Nasal mucus collected from each nasal cavity was used for in vitro bullfrog palate clearance studies and compared to the in vivo nasal ST. Mucociliary clearance rate (MTR) on frog palate was 12.5 +/- 2.5 mm/min in the mucus from control subjects, 6.1 +/- 1.5 mm/min in the mucus from the patients. The difference was statistically significant (p less than 0.005). The MTR on frog palate in the patients whose nasal ST was within normal range was significantly slower than that in controls (p less than 0.005), but not significantly different from that in the patients whose nasal ST was over the normal range. These results suggest that the nasal mucous properties which decreased the mucociliary clearance on frog palate did not contribute to the mucociliary clearance of the patients who had a normal one. No significant correlation existed between MTR on frog palate and nasal ST in both control and chronic sinusitis. In chronic sinusitis patients, decelerated nasal ST was recovered significantly by normal saline nebulization compared with the value before the nebulization (p less than 0.01). None of the significant change of ST was observed in control before and after the nebulization.  相似文献   

2.
We employed an associative learning paradigm to test the hypothesis that exercise hyperpnea in humans arises from learned responses forged by prior experience. Twelve subjects undertook a "conditioning" and a "nonconditioning" session on separate days, with order of performance counterbalanced among subjects. In both sessions, subjects performed repeated bouts of 6 min of treadmill exercise, each separated by 5 min of rest. The only difference between sessions was that all the second-to-penultimate runs of the conditioning session were performed with added dead space in the breathing circuit. Cardiorespiratory responses during the first and last runs (the "control" and "test" runs) were compared for each session. Steady-state exercise end-tidal PCO(2) was significantly lower (P = 0.003) during test than during control runs for both sessions (dropping by 1.8 +/- 2 and 1.4 +/- 3 Torr during conditioning and nonconditioning sessions, respectively). This and all other test-control run differences tended to be greater during the first session performed regardless of session type. Our data provide no support for the hypothesis implicating associative learning processes in the ventilatory response to exercise in humans.  相似文献   

3.
The oral and nasal contributions to inhaled ventilation were simultaneously quantified during sleep in 10 healthy subjects (5 men, 5 women) aged 43 +/- 5 yr, with normal nasal resistance (mean 2.0 +/- 0.3 cmH(2)O. l(-1). s(-1)) by use of a divided oral and nasal mask. Minute ventilation awake (5.9 +/- 0.3 l/min) was higher than that during sleep (5.2 +/- 0.3 l/min; P < 0.0001), but there was no significant difference in minute ventilation between different sleep stages (P = 0.44): stage 2 5.3 +/- 0.3, slow-wave 5.2 +/- 0.2, and rapid-eye-movement sleep 5.2 +/- 0.2 l/min. The oral fraction of inhaled ventilation during wakefulness (7.6 +/- 4%) was not significantly different from that during sleep (4.3 +/- 2%; mean difference 3.3%, 95% confidence interval -2.1-8.8%, P = 0.19), and no significant difference (P = 0.14) in oral fraction was observed between different sleep stages: stage two 5.1 +/- 2.8, slow-wave 4.2 +/- 1.8, rapid-eye-movement 3.1 +/- 1.7%. Thus the inhaled oral fraction in normal subjects is small and does not change significantly with sleep stage.  相似文献   

4.
Tracheal mucous velocity measurements were made in 24 beagle dogs in five age groups, using a gamma camera to detect movement of instilled 99mTc-macroaggregated albumin. Age groups were defined as immature (9-10 mo), young adult (2.8-3.0 yr), middle aged (6.7-6.9 yr), mature (9.6-9.8 yr), and aged dogs (13.6-16.2 yr). Mean velocities were 3.6 +/- 0.4 (SE) mm/min in the immature dogs, 9.7 +/- 0.6 mm/min in the young adults, 6.9 +/- 0.5 mm/min in the middle-aged dogs, 3.5 +/- 0.8 mm/min in the mature dogs, and 2.9 +/- 0.5 mm/min in the aged dogs. Tracheal mucous velocity was significantly (P less than 0.05) greater in the young adult and middle-aged groups compared with the immature, mature, and aged dogs. This pattern of age-related changes was noted to be similar to age-related changes described for certain pulmonary function measurements.  相似文献   

5.
The human vomeronasal duct (VND) is described as a tubular or pouch-like mucosal invagination of the anterior nasal septum. This study investigated shape, size and orientation of the VND using magnetic resonance imaging (MRI). Fifteen subjects participated (eight women, seven men; mean age 39 years, age range 18-66 years); they had been pre-selected with regard to the presence of a VND opening of 1 mm. MRI was performed before and after application of diluted gadolinium-diethylene-triamino-penta-acetic actetate (Gd-DTPA) into the left or right VND. A tubular structure was found in 12 subjects with a median length of 7 mm (range 3-22 mm; one VND with a length 47 mm). In three subjects a nearly circular, pouch-like structure was observed. Seven of the tubular VNDs were slightly bent upwards, the other five VNDs ran parallel to the floor of the nasal cavity. There was no significant gender-related difference in the length of VNDs. These data indicate considerable variability of shape, size and orientation of the human VND.  相似文献   

6.
药敏药片临床应用观察报告   总被引:1,自引:0,他引:1  
本文报导省市级三所医院同时用药敏药片和药敏纸片对国际标准质株做抑菌试验,其结果:药片片重差变异系数cv=2.5,纸片cv=14.4.抽样五种抗菌素抑菌环直径差变异系数分别为:药片平均cv=3.07,而纸片平均cv=6.85;均匀度L药片为2-3mm纸片为3-5mm.表明药片片间差小,均匀度、准确度合格,药物含量均匀,精密度好于纸片.  相似文献   

7.
大熊猫(Ailuropodamelanoleuca)是中国特有的珍稀动物,它们以高纤维含量的竹子为主食,但却具有与食肉动物相似的消化系统结构,为适应高纤维的食物,它们又形成了与食竹相适应的消化生理特点。其整个消化道内膜上粘液腺丰富,在野外,这些粘液腺的分泌物包裹于大熊猫所摄食的竹茎、  相似文献   

8.
Prostaglandin D2 (PGD2) was infused intravenously into normal male volunteers. Seven subjects received infusions of 16, 32, 64 ng/kg/min and six of these a further dose of 128 ng/kg/min. Each individual's maximum dose was limited by discomfort caused by intense facial flushing and nasal congestion. At these doses there was no significant effect on systolic or diastolic blood pressure nor on spirometric measurements. There was a small but statistically significant tachycardia at 64 and 128 ng/kg/min. Collagen- and adenosine diphosphate (ADP)-induced platele aggregation was not affected at any of the infusion rates. Infused PGD2 is unlikely to be a useful antithrombotic agent.  相似文献   

9.
The goal of this study was to document the effect of aging, sex and disc level on time-dependent in vivo tensile deformability of human lumbar-lumbosacral motion segments and discs in pure centric tension, when the contracting effect of muscles can be neglected. Elongations of segments L3-L4, L4-L5 and L5-S1 were measured during the usual suspension hydrotraction therapy of patients, by using a subaqual ultrasound measuring method reported in (Kurutz et al., 2002a, 2003). Patients were suspended cervically in lukewarm water for 20 min, loaded by 20-20 N lead weights on ankles. The mean initial elastic elongations (strains) of segments or discs were about 0.8 mm (10%) for patients under 40 years; 0.5 mm (6%) between 40-60 years; and 0.2 mm (3%) over 60 years. The mean final viscoelastic elongations were 1.5 mm (18%) under 40 years; 1.2 mm (15%) between 40-60 years; and 0.6 mm (7%) over 60 years. In the beginning/end of the treatment, patients of extended segments were on average 6/8 years younger than those with unextended ones. Based on the in vivo measured elongations, initial tensile stiffness was obtained in terms of aging, sex and disc level. For the above age-classes, the approximate mean tensile stiffness of less/more degenerated lumbar FSUs or discs were about 600/800, 800/1000 and 1800/2800 N/mm, respectively. A new terminology, the so-called age-sensitivity has been introduced as a value of 0.01-0.04 mm/year elongation capacity decrease per a year of aging, after the age of 35. No significant difference was found between sexes regarding age-dependence in tension.  相似文献   

10.
The objective of this study was to analyze the validity of the velocity corresponding to the onset of blood lactate accumulation (OBLA) and critical velocity (CV) to determine the maximal lactate steady state (MLSS) in soccer players. Twelve male soccer players (21.5 +/- 1.0 years) performed an incremental treadmill test for the determination of OBLA. The velocity corresponding to OBLA (3.5 mM of blood lactate) was determined through linear interpolation. The subjects returned to the laboratory on 7 occasions for the determination of MLSS and CV. The MLSS was determined from 5 treadmill runs of up to 30-minute duration and defined as the highest velocity at which blood lactate did not increase by more than 1 mM between minutes 10 and 30 of the constant velocity runs. The CV was determined by 2 maximal running efforts of 1,500 and 3,000 m performed on a 400-m running track. The CV was calculated as the slope of the linear regression of distance run versus time. Analysis of variance revealed no significant differences between OBLA (13.6 +/- 1.4 km.h(-1)) and MLSS (13.1 +/- 1.2 km.h(-1)) and between OBLA and CV (14.4 +/- 1.1 km.h(-1)). The CV was significantly higher than the MLSS. There was a significant correlation between MLSS and OBLA (r = 0.80), MLSS and CV (r = 0.90), and OBLA and CV (r = 0.80). We can conclude that the OBLA can be utilized in soccer players to estimate the MLSS. In this group of athletes, however, CV does not represent a sustainable steady-state exercise intensity.  相似文献   

11.
Mucus transport speed induced by two-phase gas-liquid interaction was measured in the continuous two-phase annular flow tube models, and factors influencing the transport speed were assessed in conjunction with rheological properties of mucus. The flow model was made with 1.0-cm-ID glass tubes and positioned either vertically or horizontally. During a continuous passage of airflow through the model tube, mucus stimulants were supplied into the tube at a rate of 0.5-2.0 ml/min. The advancing speed of the leading edge of the mucous layer and mean mucous layer thickness were then measured. The transport speed in the vertical tube model ranged from 1.1 to 3.1 cm/min with a mucus feed rate of 0.5 ml/min at airflow rates of 0.33-1.17 l/s and increased with increasing airflow rates but decreased rapidly with increasing viscosity of mucus. The transport speed increased almost proportionally with increasing mucus feed rate. Elasticity of mucus did not affect the transport speed itself. However, more elastic mucus caused lower flow resistance and thereby could be transported with a much reduced work load. The transport speed in the horizontal tube model was 5-60% faster than that in the vertical tube model. The mean mucous layer thickness in the vertical tube model was found to be in the range of 0.5-1.5 mm in the experimental conditions used, and decreased rapidly with increasing airflow rate and decreasing viscosity of mucus. From these data the transport speed could be functionally related to airway diameter, mucous layer thickness, and mucus production rate.  相似文献   

12.
Recent studies have suggested that the inhalation of cold air through the nose is associated with the subsequent release of mediators of immediate hypersensitivity. To determine if mucosal surface heat and water loss influence the nasal functional response to cold air, we measured nasal resistance by posterior rhinomanometry before and 1, 5, and 10 min after a 4-min period of isocapnic hyperventilation (30 l/min) through the nose in nine healthy subjects (5 males, 4 females; aged 25-39 yr) while they inhaled air at 0 degrees C. During the challenge period, the subjects breathed either in and out of the nose or in through the nose and out through the mouth. No changes in nasal resistance developed when subjects breathed exclusively through the nose; however, when subjects breathed in through the nose and out through the mouth, nasal resistance was increased 200% at 1 min (P less than 0.01) after the challenge and returned to baseline values by 10 min after cessation of the challenge. These data indicate that nasal functional responses to cold dry air are dependent on the pattern of the ventilatory challenge. If the heat given up from the nasal mucosa to the incoming air is not recovered during expiration (as is the case with inspiration through the nose and expiration through the mouth), nasal obstruction will occur. Hyperpnea of cold air, per se, does not influence nasal resistance.  相似文献   

13.
The paper describes the use of an objective method for the quantitative analysis of the relationship between the posterior cross-bite and the occurrence of occlusive interferences and damages to the mandible muscle elevator. Two groups of subjects were selected for the analysis: 10 patients with unilateral cross-bite and 10 students without any symptoms of temporomandibular disorders (TMD). By means of the Robert Jenkelson K5A kinesiograph we measured maximal opening velocity of the mandible (mm/s), maximal-closing velocity (mm/s), first tooth contact velocity and displacement in the vertical plane at the maximal intercuspidation (mm). The following values were obtained: maximal-opening velocity in the first group was 349 mm/s and 380 mm/s in the control group. This difference was incidental. The maximal closing velocity in the study group was 204.9 and 345.2 in the control group (p < 0.05). The first tooth contact velocity in the study group was 75.93 and 325 in the control group (p < 0.01). Displacements in the vertical plane at the maximal intercuspidation in the investigated group was 0.24 +/- 0.01 mm, while in control group that value was 0.12 +/- 0.012 mm.  相似文献   

14.
In order to compare the physiological and the subjective responses to low relative humidity of elderly and young men, we measured saccharin clearance time (SCT), frequency of blinking, hydration state of the skin, transepidermal water loss (TEWL), sebum level recovery and skin temperatures as physiological responses. We asked subjects to evaluate thermal, dryness and comfort sensations as subjective responses using a rating scale. Eight non-smoking healthy male students (21.7+/-0.8 yr) and eight non-smoking healthy elderly men (71.1+/-4.1 yr) were selected. The pre-room conditions were maintained at an air temperature (Ta) of 25 degrees C and a relative humidity (RH) of 50%. The test-room conditions were adjusted to provide 25 degrees C Ta and RH levels of 10%, 30% and 50%. RH had no effect on the activity of the sebaceous gland or change of mean skin temperature. SCT of the elderly group under 10% RH was significantly longer than that of the young group. In particular, considering the SCT change, the nasal mucous membrane seems to be affected more in the elderly than in the young in low RH. Under 30% RH, the eyes and skin become dry, and under 10% RH the nasal mucous membrane becomes dry as well as the eyes and skin. These findings suggested that to avoid dryness of the eyes and skin, it is necessary to maintain greater than 30% RH, and to avoid dryness of the nasal mucous membrane, it is necessary to maintain greater than 10% RH. On the thermal sensation of the legs, at the lower humidity level, the elderly group felt cooler than the young group. On the dry sensation of the eyes and throat, the young group felt drier than the elderly group at the lower humidity levels. From the above results, the elderly group had difficulty in feeling dryness in the nasal mucous membrane despite being easily affected by low humidity. On the other hand, the young group felt the change of humidity sensitively despite not being severely affected by low humidity. Ocular mucosa and physiology of skin by dryness showed no difference by age. In the effect of longer exposure (180 min.) to low RH, only TEWL showed a slight decrease after 120 minutes in 30% RH, and all the measured results showed no noticeable differences compared with the result at 120 minutes.  相似文献   

15.
1. Non-invasive methods were developed for measuring mammary blood flow in lactating goats. 2. A Doppler principle ultrasound device was equipped with an external detector measuring maximal blood velocity (Vmax) and average blood velocity (Vav) was calculated as Vmax/2. Volume flow then depended on determination of the angle of insonation and the cross-sectional area of the milk vein (the caudal superficial epigastric or subcutaneous abdominal vein). 3. Blood velocities were measured on the milk vein of either side of the animal while clamping the pudendal veins manually. Blood velocities ranged from 7-34 cm/sec. 4. The milk vein diameter was measured by means of a slide gauge which, for clearly protruding veins, gave similar results to that measured by ultrasound scanning. In protruding veins the cross-section was circular. In non-protruding veins the cross-section was elliptical and the slide gauge significantly (P less than 0.01) overestimated the cross-sectional area. The milk vein diameter of either side measured in 10 lactating goats was 8.8 +/- 1.1 mm (means +/- SD). 5. Blood flow ranged from 90-675 ml/min in a dry and a high-yielding (3.4 l milk daily) goat, respectively. The reproducibility of the blood flow measurements was 12-16%. 6. It is concluded that the present method may be used for quantitative measurements of mammary blood flow in goats.  相似文献   

16.
Alveolar epithelial integrity in athletes with exercise-induced hypoxemia.   总被引:1,自引:0,他引:1  
The effect of incremental exercise to exhaustion on the change in pulmonary clearance rate (k) of aerosolized (99m)Tc-labeled diethylenetriaminepentaacetic acid ((99m)Tc-DTPA) and the relationship between k and arterial PO(2) (Pa(O(2))) during heavy work were investigated. Ten male cyclists (age = 25 +/- 2 yr, height = 180.9 +/- 4.0 cm, mass = 80.1 +/- 9.5 kg, maximal O(2) uptake = 5. 25 +/- 0.35 l/min, mean +/- SD) completed a pulmonary clearance test shortly (39 +/- 8 min) after a maximal O(2) uptake test. Resting pulmonary clearance was completed >/=24 h before or after the exercise test. Arterial blood was sampled at rest and at 1-min intervals during exercise. Minimum Pa(O(2)) values and maximum alveolar-arterial PO(2) difference ranged from 73 to 92 Torr and from 30 to 55 Torr, respectively. No significant difference between resting k and postexercise k for the total lung (0.55 +/- 0.20 vs. 0. 57 +/- 0.17 %/min, P > 0.05) was observed. Pearson product-moment correlation indicated no significant linear relationship between change in k for the total lung and minimum Pa(O(2)) (r = -0.26, P > 0.05). These results indicate that, averaged over subjects, pulmonary clearance of (99m)Tc-DTPA after incremental maximal exercise to exhaustion in highly trained male cyclists is unchanged, although the sampling time may have eliminated a transient effect. Lack of a linear relationship between k and minimum Pa(O(2)) during exercise suggests that exercise-induced hypoxemia occurs despite maintenance of alveolar epithelial integrity.  相似文献   

17.
Hypoxia is important in tumor biology and therapy. This study compared the novel luminescence fiber-optic OxyLite sensor with the Eppendorf polarographic electrode in measuring tumor oxygenation. Using the relatively well-oxygenated P22 tumor, oxygen measurements were made with both instruments in the same individual tumors. In 24 air-breathing animals, pooled electrode pO(2) readings lay in a range over twice that of sensor pO(2(5min)) values (-3.2 to 80 mm Hg and -0.1 to 34.8 mm Hg, respectively). However, there was no significant difference between the means +/- 2 SE of the median pO(2) values recorded by each instrument (11.0 +/- 3.3 and 8.1 +/- 1.9 mm Hg, for the electrode and sensor respectively, P = 0.07). In a group of 12 animals treated with carbon monoxide inhalation to induce tumor hypoxia, there was a small but significant difference between the means +/- 2 SE of the median pO(2) values reported by the electrode and sensor (1.7 +/- 0.9 and 2.9 +/- 0.7 mm Hg, respectively, P = 0.009). A variable degree of disparity was seen on comparison of pairs of median pO(2) values from individual tumors in both air-breathing and carbon monoxide-breathing animals. Despite the differences between the sets of readings made with each instrument from individual tumors, we have shown that the two instruments provide comparable assessments of tumor oxygenation in groups of tumors, over the range of median pO(2) values of 0.6 to 28.1 mm Hg.  相似文献   

18.
BackgroundThe precise way in which allergen is handled by the nose is unknown. The objective of this study was to determine recovery of Der p 1 allergen following nasal administration and to determine whether Der p 1 can be detected in nasal biopsies after natural exposure and nasal challenge to allergen.Methods(1) 20 nonatopic non-rhinitics were challenged with Der p 1 and recovery was measured by ELISA in the nasal wash, nasal mucus and induced sputum up to 30 minutes. Particulate charcoal (<40 μm) served as control. (2) In 8 subjects (5 atopics), 30 to 60 minutes after challenge histological localisation of Der p 1 in the nasal mucosal epithelium, subepithelial mucous glands and lamina propria was performed. Co-localisation of Der p 1 with macrophages and IgE-positive cells was undertaken.Results(1) Less than 25% of total allergen was retrievable after aqueous or particulate challenge, most from the nasal mucus during 1-5 min after the challenge. The median of carbon particles recovered was 9%. (2) Prechallenge Der p 1 staining was associated with the epithelium and subepithelial mucous glands. After challenge there was a trend for greater Der p 1 deposition in atopics, but both atopics and nonatopics showed increases in the number of Der p 1 stained cells and stained tissue compartments. In atopics, increased eosinophils, macrophages and IgE positive cells co-localized with Der p 1 staining.ConclusionsDer p 1 allergen is detected in nasal tissue independent of atopic status after natural exposure. After challenge the nose effectively retains allergen, which remains mucosally associated; in atopics there is greater Der p 1 deposition and inflammatory response than in nonatopics. These results support the hypothesis that nasal mucus and tissue act as a reservoir for the inhaled Der p 1 allergen leading to a persistent allergic inflammatory response in susceptible individuals.  相似文献   

19.
目的:为人工椎间盘的设计提供形态学依据。方法:对56例哈萨克族成人腰椎(L)间盘高度进行放射学测量。结果:56例哈萨克族L1-2椎间盘高度男女性之间差异无统计学意义(P〉0.05),L3-5椎间盘高度男、女性之间差异有统计学意L(P〈0.005-0.001);哈萨克族与汉族腰椎间盘高度之间差异均有统计学意义(P〈0.005)。结论:哈萨克族腰椎间盘高度均大于汉族,临床上可通过对腰椎间盘间高度的测量,为人工椎间盘假体设计提供参数.  相似文献   

20.
跑台运动促进幼龄大鼠学习能力   总被引:11,自引:1,他引:10  
Lou SJ  Liu JY  Yang RY  Chen PJ 《生理学报》2006,58(4):365-369
为了探讨跑台运动对幼龄大鼠学习能力的影响,实验采用5周龄Sprague-Dawley大鼠,随机分为安静对照组和跑台运动组,其中跑台运动组大鼠以低强度进行为期一周的跑台运动;然后使用Morris水迷宫,对两组大鼠的定位航行和空间探索能力进行分析。在定位航行实验中,运动组大鼠寻找到平台的潜伏期明显短于对照组(P〈0.05);并且随着训练次数的增加,运动组大鼠的游泳速度明显高于对照组(P〈0.01);另外,运动轨迹的弯曲度表明运动组大鼠还表现出了较强的寻找平台的动机以及对平台位置较为准确的空间定位能力。在空间探索实验中,两组大鼠的游泳速度并没有明显差异,从大鼠在各象限内穿越平台相应位置的次数来看,运动组大鼠在D象限穿越的次数高于对照组,但无统计学差异(P〉0.05)。上述结果提示,低强度的跑台运动在短时间内便可以明显提高幼龄大鼠的学习能力。  相似文献   

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