Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “longevity”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,351 records · Page 75Linked to original sources
PubMed1999

Longevity of pathogenic bacteria especially Salmonella in cistern water.

Cistern-collected rain water which is used as process water for toilet flushing, cleaning purposes, garden irrigation and linen washing, was experimentally contaminated with pathogenic bacteria, Salmonella enteritidis, Yersinia enterocolitica and Campylobacter jejuni. The longevity of those pathogens was investigated considering different temperatures and contents of organic materials. Neither Salmonella enteritidis, Yersinia enterocolitica nor Campylobacter jejuni are able to grow at temperatures of 5 degrees C, 15 degrees C, 20 degrees C or 37 degrees C. The most sensitive pathogen was Campylobacter jejuni which showed rapidly decreasing of colony counts at 15 degrees C as compared with Yersinia enterocolitica or Salmonella enteritidis. For Salmonella enteritidis the decrease of bacterial concentrations was higher at 37 degrees C than at 5 degrees C. Increasing the concentrations of organic compounds by addition of bacteriological pepton or addition of extreme++ amounts of pidgeon feces lowers the rate of bacterial death but an increase in colony counts could not be observed at the different temperatures investigated. The elimination of salmonella is supported if the cisterns are layered with a biofilm and sediment. So it could be confirmed, that raised amounts of organic material, pidgeon feces together with optimal temperatures which can be observed accidentally in rain water cisterns can not enhance growth of enteropathogenic bacteria.

Animals↗
PubMed1999

Restoration longevity and analysis of reasons for the placement and replacement of restorations provided by vocational dental practitioners and their trainers in the United Kingdom.

OBJECTIVE: This study examined the reasons given by vocational dental practitioners and their trainers for placement and replacement of restorations. METHOD AND MATERIALS: Each participant was asked to record the reason for placement or replacement of restorations. The age and class of the restoration being replaced were also recorded, as was the material being used and the material being replaced (if known). RESULTS: Details of the reason for placement or replacement was received on 9,031 restorations. Of the restorations placed, 53.9% were amalgam, 29.8% were resin composite, and 16.3% were glass-ionomer cement. The reasons for placement or replacement of the restorations were principally primary caries (41.3%), secondary caries (21.9%), tooth fracture (6.4%), marginal fracture or degradation (6.1%), and noncarious defects (5.8%). Of the amalgam restorations, most were placed to restore Class II and Class I preparations (65.8% and 29.9%, respectively). Of the composite restorations, most were placed in Class III and Class V cavities (35.5% and 26.3%, respectively). Glass-ionomer cement was used predominantly to restore Class V cavities (63.5%). CONCLUSION: Secondary caries was the most prevalent reason for replacement of restorations, regardless of material. Statistical analysis indicated that amalgam provided significantly greater longevity than composite or glass-ionomer materials.

Clinical Clerkship↗
PubMed2001

Effects of nutritional factors and soil addition on growth, longevity and fecundity of the tadpole shrimp Triops newberryi (Notostraca: Triopsidae), a potential biological control agent of immature mosquitoes.

The notostracan tadpole shrimp (TPS) Triops newberryi Packard has potential to be used as a biocontrol agent of immature mosquitoes. Eggs, nymphal or adult shrimps are considered to be the stages for field introduction. To yield good growth of the shrimp and high production of shrimp eggs under artificial conditions, nutritional requirements of TPS for growth, survival and fecundity need to be elucidated. In the laboratory, we evaluated various nutritional and edaphic regimens, such as soil alone, mosquito larvae or rabbit pellets alone and various combinations of these three components for culturing. These factors influenced the growth, longevity and egg production profoundly. It was shown that the simulated natural conditions, i.e. full combination of all three factors, yielded the largest TPS with longest survival and highest egg production, followed by the combinations of any two components. Any single component, soil, mosquito larvae, or rabbit pellets, did not result in good growth, survival and egg production. By formulating optimal rearing substrates, this species of TPS will yield large numbers of all stages for experimentation and field introductions. Under optimal conditions, they mature in 7-8 days and survive for about one month. Each TPS is capable of producing up to 1,000 eggs during its lifetime. These studies developed nutritional regimens for TPS mass culturing procedures, where the eggs, nymphal and adult TPS can be mass cultured for field introduction and stocking in mosquito developmental sites.

Animal Feed↗
PubMedDate not supplied

Clinical longevity of removable partial dentures retained by telescopic crowns: outcome of the double crown with clearance fit.

PURPOSE: It was the aim of this study to investigate the long-term success of a telescopic crown system that can be used for both rigid and resilient support and to evaluate by means of a literature review whether the use of resilient support may be advantageous compared to other double crown systems when the restoration is placed on only a few remaining teeth. MATERIALS AND METHODS: Patient records were used to evaluate 125 dentures (with 460 abutment teeth) based on the Marburg double crown system. The loss of abutment teeth, endodontic treatment, and fracture of the metallic framework were investigated with regard to the different types of denture support. RESULTS: The probability that a patient would have kept all abutment teeth was 84% after 5 years and 66% after 10 years. No significant differences were found for the two groups "resilient support" (< or = three abutment teeth) and "rigid support" (> or = four abutment teeth). For abutment teeth with a double crown with clearance fit, the risk of loss was 4% after 5 years and 15% after 10 years for rigid support, and 10% and 24%, respectively, for resilient support. The risk of endodontic treatment was 7% after 5 years and 9% after 10 years for rigid support, and 3% and 7%, respectively, for resilient support. None of the denture frameworks showed a fracture during the observation period. CONCLUSION: Removable partial dentures retained by double crowns with clearance fit and constructed without major or minor connectors provide good clinical longevity. The survival rates of abutment teeth were comparable to those reported in the literature for other double crown systems. There was no significant increase of the risk of abutment loss when the restoration was placed on three or fewer remaining teeth and the concept of resilient support was applied.

Adolescent↗
PubMedDate not supplied

Failure, repair, refurbishing and longevity of restorations.

The clinical diagnosis of secondary caries is the main reason for replacement of all types of directly-placed restorations. This is an ill-defined clinical diagnosis both in teaching programs and in general practice. The criteria for the diagnosis must be improved and come in line with those for primary caries. Secondary caries are usually localized and delineated lesions and should be differentiated from stained and ditched margins. Small defects of secondary caries, stained and degraded margins may be removed by refurbishing/refinishing procedures. Larger defects may be explored by removing part of the restoration to access the defective margin. By removing part of the restoration to the full depth, a firm diagnosis can be made regarding the extent of the lesion, as the defects are often well delineated. Provided the main part of the restoration is satisfactory, the "exploratory" cavity preparation can then be filled with an appropriate material. These approaches will save tooth structure and be cost-effective. However, longevity data are lacking with such studies in progress.

Dental Caries↗
PubMed2002

Longevity and clinical performance of IPS-Empress ceramic restorations--a literature review.

A literature review of longevity and clinical performance of IPS-Empress restorations is presented. A MEDLINE search was conducted in fall 2000. Selection criteria were set so as to identify suitable clinical trials that were published in full and that had lasted more than 2 years. A total of 6 clinical trials on the performance of IPS-Empress inlays and onlays and a total of 3 clinical trials on the performance of IPS-Empress crowns were identified. Survival rates for IPS-Empress inlays and onlays ranged from 96% at 4.5 years to 91% at 7 years; most failures were due to bulk fracture. IPS-Empress crowns had a survival rate ranging from 92% to 99% at 3 to 3.5 years; crown failure was also mainly due to fracture. Dentists should inform their patients about these survival rates when offering such treatment. The use of IPS-Empress crowns in the posterior of the mouth is not recommended until the results of more long-term clinical trials are available.

Aluminum Silicates↗
PubMed2003

[Prognostic evaluation of the flying longevity of pilots with idiopathic mitral valve prolapse].

In the period of 1995-2001, 576 17- to 49-yr. old pilots of fighters and fighter-bombers with the idiopathic mitral valve prolapse (IMVP) were investigated at the Seventh Central military aviation clinical hospital. In this group, a very feebly marked mitral valve prolapse was found in 98.7% of cases. In 96.7% class-1 IMVP was accompanied by a mitral reguragitation, most often the first-degree one. Based on results of comprehensive examination, medically qualified to fly were 560 out of 576 pilots from the main group (97.0%) and 144 out of 150 pilots from the group of control (97.2%). In the next 5 years the flying career was continued by 76.3% and 78.7% of the pilots, respectively. A clinical-diagnostic and expert algorithm for medical certification of pilots of highly maneuverable aircraft with IMVP was developed which will reduce time of in-hospital medical certification and facilitate more accurately determination of the criteria for immediate and long-range estimation of the flying longevity.

Adolescent↗
PubMed1998

Alternative Total TMJ Arthroplasty: Metal-on-Metal for Longevity in Implant Survivorship and Patient Satisfaction.

Use of biomaterials as an implant device for TMJ joint reconstruction in oral maxillofacial surgery has been an ever-increasing dilemma for the oral maxillofacial surgeon. The decision to choose the best procedure and device/material in providing longevity wirh satisfaction to the patient has become a demanding factor. Maxillofacial surgeons are faced with a "young age" patient population and are in a continual struggle to find the proper device to maintain long-term survivorship without recurrent multiple operations. This multiple operation(s) factor can cause a further complication in itself, and also reduce the survivorship of implant devices. There has been a steady decrease in recent years in the number of TMJ surgical procedures performed by accredited OMS residency training programs; this may be due to the many short-term survivorship failures with certain alloplastic devices (Proplast/Teflon and Silastic) as well as the short-term survivorship of autologous tissue implants (Fascia and Grafts) and the added factor of enhanced complications with multiple surgeries. So the question asked by many oral maxillofacial surgeons is: what other procedure or biomaterial/device, if any, is available to avert the ever-present TMJ disease process and disorder?

Journal Article↗
PubMedDate not supplied

Longevity and quality of FPDs: a retrospective study of restorations 30, 20, and 10 years after insertion.

PURPOSE: The aim of this retrospective study was to investigate the longevity and clinical performance of fixed partial dentures (FPD) 30, 20, and 10 years after insertion. MATERIALS AND METHODS: A total of 289 FPDs were inserted in 1966/67, 1976/77, and 1986/87. For patients with FPDs presumably still in function, an evaluation according to the CDA criteria was made. RESULTS: For 64 of the FPDs (22%), no information was available. Seventy-nine patients with 94 FPDs (33%) were clinically examined, and 44 of the FPDs (15%) were reported to be still in function by the patients' current clinicians. The remaining 87 FPDs (30%) were considered lost to follow-up. These FPDs had either been removed for various reasons--in most cases dental caries, lost retention, or fractured abutment teeth--or the patient could not be contacted. Eighty-four percent of the FPDs inserted in 1966/67 were still in function after 20 years, compared to 64% of those inserted in 1976/77. Apart from an increase in wear and discoloration, the oldest FPDs had excellent marginal fit and anatomic shape. CONCLUSION: The survival rate of 30-year-old FPDs was high; 53% remained in function after 30 years. Based on the CDA criteria, 78% of the restorations were rated satisfactory in all subgroups. The FPDs placed in 1966/67 obtained the highest ratings in color, anatomy, and margin integrity.

Adult↗
PubMedDate not supplied

Comparison of the efficacy and longevity of nonpenetrating glaucoma surgery with and without a new, nonabsorbable hydrophilic implant.

BACKGROUND AND OBJECTIVE: To compare the efficacy and longevity of nonpenetrating glaucoma surgery with and without the use of a nonabsorbable hydrophilic implant at the Oxford Eye Centre, Johannesburg, South Africa, and the Glaucoma Unit, Jules Gonin Ophthalmic Hospital, Lausanne, Switzerland. PATIENTS AND METHODS: In a nonrandomized, prospective study between March 1997 and December 2001, 48 eyes of 32 patients aged 18 to 86 years with primary open-angle glaucoma underwent nonpenetrating glaucoma surgery; 25 eyes with the implant and 23 eyes without it. Intraocular pressure (IOP) was recorded preoperatively and postoperatively at 1, 7, and 14 days, at 1, 3, and 6 months, and thereafter every 6 months. RESULTS: The mean preoperative IOP was 27.5 +/- 11.8 mm Hg (range, 20 to 64 mm Hg) in the implant group and 24.8 +/- 7.1 mm Hg (range, 16 to 38 mm Hg) in the control group. During the first 18 months of follow-up, both groups showed identical IOP progression and the mean IOP remained less than 14 mm Hg. After 2 years of follow-up, the IOP started to rise in the control group but remained stable in the implant group. After 30 months, the mean IOP was 12.4 +/- 2 mm Hg and the IOP decrease in percentage was 62% +/- 6% in the implant group (n = 13) versus 16.1 +/- 3 mm Hg and 34% +/- 13% in the control group (n = 15) (mean IOP, P = .0022; mean IOP decrease in percentage, P = .01). CONCLUSIONS: During the first 18 months, there was no difference in the outcomes between the two groups. After 2 years of follow-up, the mean IOP was lower and the IOP decrease in percentage was greater in the implant group compared with the control group.

Absorbable Implants↗
PubMedDate not supplied

The effect of acidic maintenance solutions on catheter longevity.

Long-term urinary catheterisation is rarely completely free of complications. Catheter blockage from mineral salt encrustation occurs in 40-50 per cent of patients. Recurrent blockage is distressing to patients and carers and costly to health services in both time and resources. Laboratory-based evidence shows acidic maintenance solutions can be effective in dissolving encrustations. This is supported by clinical experience but there are few clinical studies and no well-controlled clinical trials to date. This article examines the range of evidence for the effect of maintenance solutions on catheter longevity.

Anti-Infective Agents, Urinary↗
PubMed2005

[Topical problems of health protection in childhood and juvenile age in relation to forming cadre workers' labor longevity].

Complex investigations of worker-training process have revealed that priority within the process of choosing professon and vocational training is not given to hygienic problems concerning health of workers to be. The main stages of training do not have a common hygienic goal of improving health of workers to be and making their professional work more reliable. The authors substantiate the necessity for creating a common vocational training system based upon system analysis principles and providing for the consistent maintenance and improvement of students' health throughout the training process, including such stages as vocational guidance, vocational selection and training, to prolong professional longevity of qualified workers.

Adolescent↗
PubMed2005

Fibronectin preadsorbed on hydroxyapatite together with rough surface structure increases osteoblasts' adhesion "in vitro": the theoretical usefulness of fibronectin preadsorption on hydroxyapatite to increase permanent stability and longevity in spine implants.

OBJECTIVE: The aim of this study was to investigate the contribution of fibronectin (FN) preadsorption to enhance osteoblast adhesion and strength on hydroxyapatite (HA) used either as osteoconductive bone substitute or precoating of pedicle screws and cages in spine surgery. METHODS: HA substrata with two different surface roughness values (rough HA180 and smooth HA1200) were produced, and human osteoblasts were seeded after culturing on them. Prior to osteoblast seeding, the HA substrata were immersed in FN solution. Osteoblast attachment on each of the two HA substrata was evaluated by recording the number of cells, whereas osteoblast adhesion strength was determined by measuring the shear stress required to detach the cells from the HA substrates. RESULTS: FN preadsorption increased the number of attached osteoblasts on smooth and rough HA substratum at 40% and 62%, respectively, whereas it increased osteoblast attachment strength on the smooth and rough substratum at 165% and 73%, respectively. CONCLUSIONS: This study showed that FN preadsorption and rough HA surface texture synergistically increased "in vitro" both the number and the adhesion strength of human osteoblasts. Further studies in primates and humans should be carried out to disclose the clinical relevance (increase implant's stability and longevity) of the above-mentioned observations.

Adsorption↗
PubMed2005

Longevity of occlusally-stressed restorations in posterior primary teeth.

PURPOSE: To compile a survey of the longevity and reasons for failure of stainless steel crowns, amalgam, glass-ionomer, composite and compomer restorations in stress-bearing cavities of primary molars. METHODS: This work reviewed the dental literature of 1971 up to July 2003 for longitudinal, controlled clinical studies and retrospective cross-sectional studies. Only studies investigating the clinical performance of restorations in primary teeth with an observation period of at least 2 years were included. Annual failure rates of stainless steel crowns, amalgam, glass-ionomer, composite and compomer restorations were determined and failure reasons were discussed. RESULTS: Annual failure rates in stress-bearing cavities of primary molars were determined to be: 0-14% for stainless steel crowns, 0-35.3% for amalgam restorations, 0-25.8% for glass-ionomer restorations, 2-29.1% for atraumatic restorative treatments, 0-15% for composite restorations, and 0-11 for compomer restorations. Main reasons for failure were secondary caries, marginal deficiencies, fracture, and wear.

Compomers↗
PubMed1992

Motility longevity of sperm samples processed for intrauterine insemination.

This study demonstrates that sperm from men with male factor infertility and sperm obtained by electroejaculation have reduced motility longevity when compared with normal specimens. After 24 hours, normal samples lost only 34% of initial motility, whereas male factor patients lost 48%, and electroejaculation patients dropped 66%. Based on these data and previous clinical studies of insemination timing, it is recommended that sperm retrieval and artificial insemination for male factor infertility, especially when electroejaculation is necessary, be performed 24 to 36 hours after urinary detection of the LH surge or as close to the time of ovulation as possible.

Ejaculation↗
PubMedDate not supplied

Nurses' impact on the choice and longevity of vascular access.

A preponderance of data highlights significant improvements in outcomes when patients dialyze with arteriovenous fistulae compared with either catheters or grafts. "Fistula First" is a nationwide, evidence-based, quality improvement effort that is striving to improve vascular access outcomes by increasing the percentage of patients who dialyze with arteriovenous fistulae. Nephrology nurses will have a profound effect on achieving the goals outlined by Fistula First, including both the choice and longevity of vascular accesses.

Arteriovenous Shunt, Surgical↗
PubMed2006

Experimental usage of hydroxyapatite preadsorption with fibronectin to increase permanent stability and longevity of spinal implants.

UNLABELLED: Hydroxyapatite has been used in orthopaedic and particularly in spinal surgery by precoating implants to indirectly increase osteoblasts' adhesion and subsequently their stability and longevity. Fibronectin preadsorption synergistically with appropriately constructed hydroxyapatite's surface texture to enhance osteoblasts' adhesion has not been, to the authors' knowledge, previously investigated. In osteoporotic spines, methods to increase implant stability (pedicle screws and cages) are of major value. OBJECTIVE: This experimental study investigated the contribution of fibronectin preadsorption to enhance osteoblasts' adhesion and strength on hydroxyapatite. METHODS: Hydroxyapatite substrata with two different surface roughnesses (rough HA180 and the smooth HA1200) were produced and human osteoblasts were seeded on them after culture. Prior to osteoblasts seeding, the hydroxyapatite substrata were immersed in fibronectin solution. Osteoblast attachment on each of the two hydroxyapatite substrata was evaluated by recording the number of cells, while the osteoblast's adhesion strength was determined by measuring the shear stress required to detach the cells from the hydroxyapatite substrates. RESULTS: Fibronectin preadsorption increased the number of attached osteoblasts on smooth and rough hydroxyapatite substratum at 40% and 62% respectively, while it increased osteoblast attachment strength on the smooth and rough substratum at 165% and 73% respectively. CONCLUSIONS: Fibronectin preadsorption and smooth hydroxyapatite surface texture synergistically increased the adhesion's strength of human osteoblasts "in vitro", while preadsorption and rough hydroxyapatite surface increased the number of attached osteoblasts. Further studies in primates and human beings should be carried out to disclose the clinical relevance of the above mentioned observations in spine surgery.

Coated Materials, Biocompatible↗