Variation of aortic blood velocity with age at rest and during exercise in normal subjects.

The effect of age on aortic blood velocity signal and its derived indices of left ventricular function namely peak velocity, stroke distance (the velocity-time integral) and minute distance (stroke distance x heart rate) was studied at rest and at maximal-tolerated supine exercise using a 2-mHz continuous-wave Doppler ultrasound applied via the suprasternal notch in 66 normal healthy volunteers. The peak velocity, stroke distance and the minute distance, both at rest and at maximal exercise decreased with advancing age by 1-1.1% per annum between the ages of 20 and 70 years.

Increased axonal regeneration over long nerve gaps using autologous nerve-muscle sandwich grafts.

Poor recovery is seen after repair of long defects in peripheral nerves when denatured muscle grafts or regeneration chambers providing physical support alone are used. The presence of Schwann cells and neurotrophic factors is required for axons to migrate significant distances. In this study we have used immunohistochemical techniques and axon counts to quantify the regeneration seen when 5 cm defects in rabbit sciatic nerve were repaired with a composite graft consisting of 2-3 mm lengths of fresh autologous nerve sandwiched between 1 cm frozen-thawed muscle grafts.

Near infra-red spectroscopy: a non-invasive monitor of perfusion and oxygenation within the microcirculation of limbs and flaps.

Reliable early detection of adverse circulatory changes within a flap following free tissue transfer and early re-exploration are vital to minimise flap failure. Most surgeons rely on clinical assessment to monitor these changes but techniques such as plethysmography and laser Doppler have their advocates. These methods are limited however to measuring changes close to the surface.

Serum cortisol levels are related to moods of elation and dysphoria in new mothers.

Serum cortisol levels were measured in 163 women on the third day after childbirth. Significantly elevated levels of cortisol were found to be associated with the "blues," and significantly lower levels characterized women who exhibited mild hypomania (the "highs"). Low levels of cortisol were independently associated with epidural anesthesia, while elevated levels were related to assisted delivery.

The functional and psychological outcomes of juvenile chronic arthritis in young adulthood.

The functional and psychological outcome of 43 patients with polyarticular juvenile arthritis was assessed in order to evaluate the impact of disease on their quality of life. Mean disease duration was 19.7 yr (range 10-39 yr), mean age 26.

The influence of operator transducer pressure on ultrasonographic measurements of amniotic fluid volume.

Objective: Our purpose was to study the effect of operator transducer pressure on amniotic fluid index and single deepest pool measurements and their intraobserver and interobserver variability.

Study Design: Forty subjects in the third trimester with intact membranes were studied by two observers at three predetermined operator pressures. Pressure was measured by interfacing a flexible water-filled reservoir connected to a manometer between the maternal abdomen and the ultrasonography transducer.

Embryogenesis and plant regeneration of pakchoi (Brassica rapa L. ssp. chinensis) via in vitro isolated microspore culture.

Isolated microspores of various populations of three varieties of the Chinese cabbage pakchoi (Brassica rapa ssp. chinensis) were cultivated in vitro on NLN82 medium (Lichter 1982) and embryos and plantlets obtained with nine cultivars. The best embryo yield per bud was 57.

Modification of the iso-shunt lines for low inspired oxygen concentrations.

Arterial PO2 (PaO2) has been related to inspired oxygen concentration (FIO2 range 0.21-0.60) in 20 patients, breathing spontaneously, while recovering from a range of conditions treated in an intensive therapy unit.

The use of biobrane II and specialty airflow beds (FluidAir Plus and Kinair for effective coverage of extensive posterior donor site wounds.

Posterior skin graft donor sites furnish large areas of skin for wound coverage, but the sites frequently are management problems. The wounds tend to become moist and to develop excessive drainage and fluid accumulation that may interfere with adherence of dressings, including our preferred donor site dressing, Biobrane II (red label, large pore). We studied the use of specialty airflow beds for improving the outcome of posterior donor sites.

Altered expression of cell adhesion molecules in uninvolved gut in inflammatory bowel disease.

Adhesion of circulating cells to vascular endothelium occurs in the early phase of inflammation, and is mediated by specific cell adhesion molecules. Many such adhesion molecules are increased in inflamed regions of ulcerative colitis (UC) and Crohn's disease (CD) but there is limited knowledge of their expression in the uninvolved gut, adjacent to inflammation. We investigated immunohistochemically the expression of platelet endothelial cell adhesion molecule-1 (PECAM-1), intercellular adhesion molecule-1 (ICAM-1) and lymphocyte function-associated antigen-1 (LFA-1) on resected specimens taken at a distance of 2-4 cm from the inflamed area and without histological signs of inflammation.

Quantitation of cytokine levels in skin graft donor site wound fluid.

We quantified endogenous levels of multiple cytokines in skin graft donor site wounds in patients with small to moderate-sized burn injuries. Thirteen patients aged 11 months to 61 years with mean TBSA burn of 4 +/- 1 per cent underwent placement of occlusive wound dressings on partial skin thickness donor site wounds. Fluid was aspirated from beneath the dressing on postoperative day 1 and every subsequent 24 h until no further fluid could be obtained.

Nocturnal desaturation and serum erythropoietin: a study in patients with chronic obstructive pulmonary disease and in normal subjects.

1. To clarify the relationship between nocturnal oxygen desaturation and erythropoietin production in patients with chronic obstructive pulmonary disease, we determined arterial oxygen saturation and serum immunoreactive erythropoietin levels over 24 h in eight patients with chronic obstructive pulmonary disease and in nine normal subjects. 2.

Does epidural analgesia influence the mode of delivery in primiparae managed actively? A preliminary study of 1250 women.

We studied 1250 primiparous women with a singleton pregnancy, gestational age at delivery of 37-42 weeks, with a single live fetus, vertex presentation whose first and second stages of labour were managed according to strict criteria for the active management of labour. 568 (45%) received epidural analgesia (bupivacaine 0.25%) during labour, and the other 682 (55%) received either Entonox, pethidine or no analgesia.

Venous leg ulcers: a prognostic index to predict time to healing.

Objective: To evaluate the prognostic factors in uncomplicated venous leg ulcer healing.

Design: Randomised parallel group controlled trial with subjects stratified by initial ulcer diameter and four months' maximum duration of follow up.

Setting: Assessment at Northwick Park Hospital vascular unit with community based treatment.

Clinical trials of a living dermal tissue replacement placed beneath meshed, split-thickness skin grafts on excised burn wounds.

We evaluated the ability of Dermagraft (Advanced Tissue Sciences, La Jolla, Calif.), a living tissue analog that is composed of human neonatal fibroblasts, which are grown on a polyglactin acid Vicryl mesh (Ethicon Inc., Somerville, N.

Auditory evoked response and awareness: a study in volunteers at sub-MAC concentrations of isoflurane.

We have investigated the relationship between the auditory evoked response (AER) and simple tests of conscious awareness at four end-expiratory concentrations (0.0, 0.1, 0.

Somatosensory and auditory evoked responses recorded simultaneously: differential effects of nitrous oxide and isoflurane.

Auditory (AER) and somatosensory evoked responses (SSER) were recorded simultaneously in eight patients under anaesthesia before surgery. We studied the effects of equi-MAC end-expiratory concentrations of isoflurane (0.65-0.

Effects of four common anticonvulsants on the high pressure nervous syndrome in the rat.

This study reports results from experiments designed to test common, clinically useful anti-convulsants for their effectiveness, if any, against the high pressure nervous syndrome (HPNS) in rats. Phenytoin, carbamazepine, phenobarbitone, or diazepam were administered orally to rats before compression. Endpoints used to assess the progression of the HPNS were T1, T3, and T5 (onset of, continuous, and severe tremor), myoclonus, and seizures.

Low-flow anaesthesia. Practice, cost implications and acceptability.

An 8-week survey was conducted to determine whether the introduction of low-flow anaesthesia (a fresh gas flow of 4 litres/minute or less) into routine use would be acceptable to members of a representative anaesthetic department and if the consequent reduction in use of volatile anaesthetics would result in financial savings. The hourly consumption of the volatile agents was measured during anaesthesia conducted using either conventional or low fresh gas flows. Anaesthetists' acceptance of low-flow anaesthesia was assessed using a questionnaire.

Effect of exposure to high pressure on subsequent spatial learning and memory in rats.

The effects of high helium pressure on the subsequent acquisition of spatial memory were studied in male rats. Thirty-two rats were exposed to 65 ATA helium-oxygen pressure for 4.2 days, decompressed (total time in chamber 5 days), and then tested in an eight-arm radial maze.

Effect of general anaesthesia on the pharynx.

Conventional lateral radiography was used in 18 elderly male patients to investigate the changes induced by general anaesthesia in the upper airway. The effect of tongue traction under anaesthesia was studied similarly in another 11 patients. Following induction of anaesthesia, there were highly significant approximations to the posterior pharyngeal wall of the soft palate (median change 1.

Oxylog studies of energy expenditure and schistosomiasis in the Sudan.

The effects of varying intensities of S. mansoni infection on physical work performance in agricultural tasks were studied in 269 male farmers living in the highly endemic Gezira area of the Sudan. The subjects were in the age range 18-50 years, and they were subdivided into four infection groups: non-infected (passing no S.

Levels of consciousness in volunteers breathing sub-MAC concentrations of isoflurane.

Eight volunteers inhaled isoflurane in concentrations of 0.1, 0.2 and 0.