Plasma renin activity, angiotensin Ⅱ, Aldosterone and cortisol in 380 healthy subjects were measured by radioim-munoassay at 10, 3700 and 4300 metres above sea level. The results showed as follows: Firstly, no significant difference was noted between Tibetan and Han residents at high altitudes with reference to these four parameters. Secondly, the renin-angiotensin-aldosterone system and adrenocortical function in residents at high altitude revealed hypofunction. Thirdly, the responsiveness of aldosterone to renin declined gradually with increasing altitude, and slope declined as well. These changes might be considered as a chronic adaptive mechanism in residents at high altitude to hyposic environment.It may be suggested that appropriate use of adrenocorticosteroids may be of some clinical value in the prevention and treatment of some altitude-induced diseases.

A method for on-line real-time estimation of myocardial contractility parameters at the isovolumetric period of the left ventricular pressure wave form using Maxwell mode of cardiac muscle is described. After simplifing the mathematical mode., we presented a new technique to calculate the Vmax using 1/Vce versus p linear regression, A measuring system based on IBM-PC/XT microcomputer was developed as well. The system is employed in physiological experiments for evaluation of myocardial contractility under control condi- tions, as well as after drug administration.

Various chemical and gas-liquid chromatographic analyses indicate that the lipid A backbone of the lipopolysaccharide (LPS) isolated from Bacteriodes fragilis NCTC 9343 is chemically constituted by a ?1, 6-interlinked D-gluco-samine disaccharide. It is phosphorylated at its 1-position by a glycosidic-linkage while the ester-bound phosphate present generally in other lipid A is depleted. The lipid A is lower fatty acylated in the amount of 5.2 fatty acids per lipid A molecule (of which 0.73 forms 3-acyloxyacyl groups). The LPS containing such a lipid A component has been shown endowing with a weaker endotoxicity.

PURPOSE: Sinus elevation procedures have become a routine and reliable way to gain bone volume in the edentulous maxilla for dental implant placement. Presence of bony septations and pathology in the maxillary sinus often cause complications leading to graft or implant failure or both. The aim of this study was to retrospectively evaluate the prevalence of pathology, direction of the septa, and sinus width measured at 2 mm, 5 mm, and 10 mm from the sinus floor in maxillary sinuses using cone-beam computed tomography (CBCT). MATERIALS AND METHODS: Seventy-two sinuses from 36 random preoperative CBCT scans referred for implant therapy were retrospectively evaluated for the number, prevalence, and direction of bony septations and presence of pathology. Width of the sinus was also measured at 2 mm, 5 mm, and 10 mm from the sinus floor to account for the amount of bone available for implant placement. RESULTS: Maxillary sinus septa were found in 59.7%. Presence of a single septum was noted in 20 sinuses (27.7%), followed by two septa in 17 sinuses. The most common direction of the septum was the transverse direction. Retention pseudocyst and mucosal thickening were the most commonly seen abnormality/pathology. CONCLUSION: Based on the high prevalence of septa and sinus pathology in this sample, a preoperative CBCT scan might be helpful in minimizing complications during sinus augmentation procedures for dental implant therapy.
Cone-Beam Computed Tomography* ; Dental Implants ; Maxilla ; Maxillary Sinus* ; Pathology* ; Prevalence* ; Retrospective Studies* ; Transplants