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At least 19 recordsLinked to original sources
PubMedDate not supplied

[Transmission of the anterior chamber pressure to the center of the vitreous body and to the posterior pole of the eye of the miniature swine. Measurement of isovolumetric and direct pressure].

Experimental variations of the anterior chamber pressure (P.I.C.) are transmitted at about 300 ms to the middle of the vitreous. The response time to a sudden experimental increase in P.I.C. to the centre of the vitreous is variable and depends essentially on the control intra-ocular pressure: the more it is raised the shorter the response time. The pressure in the centre of the vitreous (P.I.V.) has a pulsatile character probably due to transmission of arterial pulsation. The higher the intra-ocular pressure the greater the amplitude of these pulsations. Recording of P.I.V. close to the surface of the retina show abrupt falls despite the fact that the P.I.C. and systemic arterial pressure remain stable. These results are discussed in relationship to autoregulation of the retinal circulation and the physiopathology of glaucoma.

Animals↗
PubMed1992

The effects of closed-head injury on postural sway.

The purpose of this study was to determine the effects of closed-head injury upon postural sway. Forty-eight subjects (26 males and 22 females) between the ages of 18 and 45 were equally divided into four groups corresponding to their level of head injury. Group 1 had not incurred a head injury, group 2 members incurred head injuries but did not lose consciousness, group 3 lost consciousness for less than 6 h, and group 4 lost consciousness for greater than 6 h. All subjects were at least 1 yr postinjury. Each subject performed three trials of six variations of the Romberg test. The center of pressure transmitted through the bottom of the feet was monitored during each 30-s trial. Total, anterior-posterior (AP), and medial-lateral (ML) sway was calculated from center of pressure data. The severely head-injured group generally evidenced greater AP sway than the other three experimental groups for all but one test condition. It was concluded that closed-head injury, particularly when associated with relatively long periods of unconsciousness, results in postural instability.

Adult↗
PubMed1979

Management of pressure sores in a specialty center. A reappraisal.

We report a study on the surgical management of 145 pressure sores in 115 patients treated in a spinal cord injury center. There is a definite trend toward better education of these patients, who do not develop their first pressure sores until years following the injury. When the patient comes in for an ulcer, he is usually healthy and the ulcer is small and clean. In such instances the ulcer can be excised and closed, preferably with a myocutaneous flap, and the patient can usually begin sitting by the 21st post-operative day. In the ideal setting he may be discharged to his home on a custom-fitted (for pressure) cushion within 4 to 5 weeks, without increasing the risk of recurrence. Prophylaxis for the future is, probably, the most essential part of the treatment.

Debridement↗
PubMed1975

Normal postural stability and steadiness: quantitative assessment.

A force platform was utilized to provide a new and sensitive means to measure postural steadiness and stability. Normal standards are presented for the center of pressure of the vertical supportive force during standing and sustained weight-shifting of normal men in three age groups. Two distinguishing characteristics were seen for normal upright posture: (1) a large area of stability over which weight can be safely shifted and maintained, and (2) steadiness such that the center of pressure fluctuates incessantly, traversing large total excursions, while remaining remarkably close to the mean point. The youngest age group showed the greatest steadiness and stability and the oldest group showed the least.

Adult↗
PubMed2026

[Effect of electroacupuncture combined with suspension exercise therapy on lower limb motor function in elderly patients with post-stroke spastic hemiplegia].

OBJECTIVE: To observe the efficacy of electroacupuncture (EA) combined with suspension exercise therapy in elderly patients with post-stroke spastic hemiplegia and its effect on lower limb motor function. METHODS: A total of 120 elderly patients with post-stroke spastic hemiplegia were enrolled. Using a 2&#xd7;2 factorial design, all the patients were assigned to a group A (conventional treatment), a group B (conventional treatment combined with suspension exercise therapy), a group C (conventional treatment combined with EA at Jiaji [EX-B2] and limb acupoints), and a group D(conventional treatment combined with suspension exercise therapy and EA at Jiaji [EX-B2] and limb acupoints), with 30 patients in each group. The main acupoints were bilateral Jiaji (EX-B2) points at the C2-C7, T2-T12, L1-L5, and S1 segments. The adjunct acupoints included Jianyu (LI15), Binao (LI14), Huantiao (GB30), Chengfu (BL36), etc. on the affected side.Continuous wave was applied at a frequency of 100 Hz with a current intensity of 1.5-3.0 mA, and needles were retained for 30 min, once daily for 4 weeks. Before treatment and after 2 and 4 weeks of treatment, the modified Ashworth scale (MAS),Fugl-Meyer assessment (FMA), Berg balance scale (BBS), and Barthel index scores were evaluated in the four groups. Root mean square (RMS) values of surface electromyography (sEMG) of the erector spinae and rectus abdominis muscles on the affected side, as well as balance function indexes, including the mean pressure symmetry index (SI), contact area SI, ellipse area, and displacement distances of the center of pressure in the anteroposterior (AP) and mediolateral (ML) directions, were measured. Clinical efficacy was also compared among the four groups. RESULTS: After 2 and 4 weeks of treatment, MAS scores in all groups were lower than those before treatment (P<0.05), whereas FMA, BBS, and Barthel index scores were higher than those before treatment (P<0.05). After 4 weeks of treatment, MAS scores were lower than those after 2 weeks of treatment (P<0.05), whereas FMA, BBS, and Barthel index scores were higher than those after 2 weeks of treatment (P<0.05) in the four groups. At both 2 and 4 weeks after treatment, group D had lower MAS scores (P<0.05) and higher FMA,BBS, and Barthel index scores (P<0.05) than the other three groups. After 2 and 4 weeks of treatment, RMS values of sEMG of the erector spinae and rectus abdominis muscles on the affected side at all tested angles were higher than those before treatment in all groups (P<0.05), and the values after 4 weeks of treatment were higher than those after 2 weeks of treatment(P<0.05). At both 2 and 4 weeks after treatment, all these indexes in the group D were higher than those in the other three groups (P<0.05). After 2 and 4 weeks of treatment, the mean pressure SI, contact area SI and ellipse area of each group were lower than those before treatment (P<0.05). After 4 weeks of treatment, the mean pressure SI, contact area SI and ellipse area of each group were lower than those after 2 weeks of treatment (P<0.05). After 2 and 4 weeks of treatment, the AP displacement distances of groups A, C and D were lower than those before treatment (P<0.05), and after 4 weeks of treatment, the AP displacement distances of groups A, C and D were lower than those after 2 weeks of treatment (P<0.05);after 2 weeks of treatment, there was no statistically significant difference in AP displacement distance in the group B compared with before treatment (P>0.05), and after 4 weeks of treatment, the AP displacement distance of group B was lower than that before treatment (P<0.05). After 2 weeks of treatment, there was no statistically significant difference in ML displacement distance in group A compared with before treatment (P>0.05); after 4 weeks of treatment, the ML displacement distance of group A was lower than that before treatment (P<0.05). After 2 and 4 weeks of treatment, there was no statistically significant difference in ML displacement distance in the group B compared with that before treatment (P>0.05).After 2 and 4 weeks of treatment, the ML displacement distances of groups C and D were lower than those before treatment(P<0.05), and after 4 weeks of treatment, the ML displacement distances of groups C and D were lower than those after 2 weeks of treatment (P<0.05). At both 2 and 4 weeks after treatment, mean pressure SI, contact area SI, ellipse area, and AP and ML displacement distances in the group D were lower than those in the other three groups (P<0.05). Factorial analysis of variance showed that EA had the strongest main effect on FMA score (F=6.243, P<0.05), suspension exercise therapy had the strongest main effect on BBS score (F=6.292, P<0.05), and the interaction effect was most significant for MAS score (F=5.941, P<0.05), indicating that the combined therapy produced a greater synergistic effect on reducing muscle tone than on the other outcome measures. The total effective rate in the group D was 93.3% (28/30), which was higher than those in the group A (53.3% [16/30]), group B (56.7% [17/30]), and group C (66.7% [20/30], P<0.05). CONCLUSION: EA combined with suspension exercise therapy could effectively promote the recovery of lower limb function in elderly patients with post-stroke spastic hemiplegia, improve motor and balance functions, and enhance activities of daily living.

Humans↗
PubMed1992

Toxicology consultation fees to health care facilities: a successful revenue generating program for poison centers.

Poison information center funding is a continuous problem and is growing more critical as cost containment effects the health care industry. Although a limited number of poison centers are partially funded by governmental agencies, general poison center operational support is derived from a variety of sources, and there is significant pressure upon centers to identify alternative funding sources. Affiliated members of our member hospital treatment network have provided one revenue source, but not all hospitals within our service region have subscribed. Furthermore, hospitals outside of our service region have utilized the service without any financial responsibility despite recommendations to use their local center. Therefore, to provide an incentive for local hospitals to subscribe to the service and to dissuade hospitals from outside of the region from using the service, we implemented a toxicology consultative fee for service on all calls emanating from non-member hospitals. In just 19 mo, recruitment of 16 new member hospitals has generated $65,150 additional revenue. Non-member hospitals electing not to affiliate but to remunerate for toxicology consultations (226 cases) have generated $20,400 (98% collection rate). A startling 95% reduction in calls from hospital outside of region has resulted since this fiduciary initiative began. New revenue totaling $85,550 has been generated by establishment of a toxicology consultation fee, and our staff is now able to dedicate priceless time and resources to the poison information needs of the residents of our region.

Fees and Charges↗
PubMed1976

Treatment of lumbar disks with chymopapain.

Symptoms arising from a herniated disk appear when the nucleus pulposus or soft inner portion of the disk bulges against a nerve root. When conservative treatment fails to help the patient, the enzyme chymopapain is currently being used in the treatment of such conditions. Injected directly into the disk, the chymopapain dissolves the nucleus by enzymatic action which selectively breaks certain bonds within the nucleus. The pressure within the center is decreased, hence the pressure against the nerve root is relieved, alleviating the symptoms. Because back care is particularly important following such treatment, physical therapy is valuable in promoting continued relief. The major emphasis of the therapy back care program is on abdominal strengthening exercises and postural training.

Chymopapain↗
PubMed1992

[A new method of gait analysis in Duchenne muscular dystrophy].

We assessed gait in Duchenne muscular dystrophy (DMD) mainly by determining alteration of foot pressure using a new gait analyzing procedure. DMD patients showed a characteristic foot pressure pattern according to their degree of dysfunction. In stage I disease, the observed pattern was the same as that of normal controls. In stage II, the period during which the center of foot pressure was seen in the front part of the foot was prolonged. This change became more marked in stage III. In stage IV, the center of foot pressure began at the head of the ossis metatarsalis primi and moved back and toward the lateral side. Thereafter, the center of foot pressure again moved forward along the outside of the foot. These changes were considered to be the result of talipes equinus and waddling gait, which are commonly demonstrated in patients with DMD.

Adolescent↗
PubMed1992

The effects of visual factors and head orientation on postural steadiness in women 55 to 70 years of age.

This study was designed to establish reference data for the effects of head position and visual conditions on the standing posture of healthy women ages 55 to 70. Center of pressure (CoP) data were analyzed using ANOVA models. Total CoP displacement was 45% greater (significant, p less than .05) when the subjects stood with their heads back and their eyes closed, as compared to standing looking straight ahead. Visual surrounds consisting of vertical visual cues resulted in less postural sway (PS) than surrounds made of horizontal visual cues (significant, p less than .05 for anteroposterior CoP range). Experimentally reduced visual acuity resulted in greater PS, while changes in ambient lighting and spatial frequency of visual cues affected PS minimally. These results suggest that a reduction in the height of shelving, and the provision of high-contrast visual cues and vertical geometric patterns are potential intervention strategies to optimize vestibular sensory input and visual orientational cues for the maintenance of stability during stance.

Aged↗
PubMed2026

High-altitude hypoxia alters the visual control of standing balance in lowlanders and Tibetan highlanders.

High-altitude hypoxia affects both visual function and postural control, yet the influence of optic-flow perturbations on standing balance under hypoxic stress remains unclear. Tibetan highlanders (TH) exhibit adaptations to chronic hypoxia, but whether their visually driven postural responses differ from those of lowlanders (LL) has not been investigated. We examined how high-altitude exposure and acclimatization influence static and dynamic visual contributions to balance by delivering sinusoidal optic-flow perturbations in virtual reality at low altitude (1,400 m) and after incremental ascent to high altitude (4,300 m) in acclimatizing LL (n = 15) and TH (n = 14). Anteroposterior center of pressure (AP CoP) velocity and mean power frequency (MPF) were measured during three visual-field conditions (full-, central-, and peripheral-vision) and two optic-flow velocities (peak 1 m/s and 8 m/s at 0.25 Hz). At high altitude, both groups showed attenuated responses to optic flow compared with 1,400 m, reflected by reduced AP CoP velocity and lower MPF across visual-field conditions, consistent with reduced responsiveness to dynamic visual-motion cues under high altitude hypoxia. In contrast, during eyes-open quiet stance [no virtual reality (VR)], TH but not LL exhibited increased AP CoP velocity and MPF at 4,300 m, and no altitude effect was observed with eyes-closed in either group. This finding indicates that TH adopt a visually dependent postural strategy at altitude, whereas LL show minimal changes in static visual balance control but reduced responsiveness to fast dynamic motion. Together, these findings demonstrate that high-altitude hypoxia disrupts dynamic visual processing for balance control in both groups, while revealing group differences in the use of static visual cues during quiet stance.NEW & NOTEWORTHY This is the first study to investigate how high-altitude hypoxia alters visually driven postural control using virtual reality (VR) optic-flow perturbations. We show that hypoxia attenuates sway responses to optic-flow in both lowlanders and Tibetan highlanders, and that visual weighting differs between these groups. These findings reveal altitude- and population-related changes in sensory weighting during standing balance, advancing sensorimotor understanding of postural control in hypoxia.

Humans↗
PubMed1978

Dynamic features of standing and their correlation with neurological disorders.

Standing posture is a result of complex activity of the human control system. Irregularities of postural control may be expected to result in deviations from normal standing. In the present study a ballistic monitoring technique was employed to establish criteria for assessment of postural disorders. Two "Kistler" force plate dynamometers were used to measure changes in the weight bearing components of each foot and displacement of the center of pressure of each foot. The patterns were analysed separately, and it was found that each of the monitored parameters demonstrated three modes of oscillation--termed Tremor, Ataxia and Sway. Statistical analysis conducted on three groups of subjects (normals, post-C.V.A. hemiplegics and brain injured) revealed significant intergroup differences in movement patterns. Good agreement was found between the interpretation of the ballistic features and the clinical diagnosis.

Ataxia↗
PubMed1977

The adrenergic nervous system and hypertension state of the art.

This discussion concerns an overview of our considerations of the adrenergic nervous system with respect to those areas of the nervous system that provide direct sensory input to the brain in control of arterial pressure; those brain centers that also participate in regulating arterial pressure; certain neurohumoral considerations; peripheral neuronal-humoral interactions; and adrenal medullary and catecholamine biosynthesis and metabolism. Also considered is the role of behavior as it may impinge upon the regulation and maintenance of an elevated arterial pressure and, finally, a variety of interactions with other pressor mechanisms that may alter adrenergic function, including hemodynamics and certain endogenously released hormones. It is from further understanding of such adrenergic mechanisms that undoubtedly greater mastery of our present gaps in knowledge will result which will substantiate how adrenergic mechanisms participate in the pathogenesis and pathophysiology of hypertension.

Adrenal Medulla↗