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61.

Aim

Several methods permit the measurement of geometric parameters of the cornea, but until now biomechanical conditions of the cornea have been ignored (e.g. in refractive corneal surgery). Besides the geometric condition, biomechanical properties of the cornea have been shown to influence applanation measurement of intra-ocular pressure (IOP) and epidemiological studies have identified corneal thickness as an independent risk factor for the development and progression of glaucoma. The aim of this investigation was to characterize the biomechanical properties of the cornea using the ocular response analyzer (ORA).

Methods

The ocular response analyzer (ORA) is a new method available for non-contact measurement of the biomechanical properties of the cornea. We evaluated the reproducibility of measurements, the difference between static and dynamic factors and the impact of independent factors (e.g. IOP, age, CCT, swelling of the cornea) on 2,500 measurements of corneal hysteresis (CH) and corneal resistance factor (CRF).

Results

In a large sample size we observed changes in CH and CRF after refractive surgery procedures (LASIK, UV-A cross-linking, keratoplasty) and in other corneal disorders (keratoconus, corneal dystrophies).

Conclusions

CRF and CH changes may reflect structural changes of the cornea. Thus, the ORA provides valuable information for a better understanding and characterization of the biomechanical condition of the cornea, especially with regard to diseases such as keratoconus and glaucoma.  相似文献   
62.
This was a prospective cohort study of 145 seniors attending a senior’s clinic and social day program using a self-administered questionnaire. Its objective was to evaluate the awareness, knowledge, risk factors and current treatment of osteoporosis in our two patient groups. A secondary objective was to determine differences between the two cohorts, and between men and women. Participants included 39 men and 106 women, with an average age of 76 years. Of these, 89% were aware of osteoporosis and 61% gave the correct definition. Awareness and accurate definition were less in men compared with women (p<0.01, and p<0.05) and clinic compared to day program groups (p<0.01). Only 54% of men knew osteoporosis could affect them. Television, newspapers and friends were identified as the main source of information. Physicians ranked as fifth as a source of information. In all, 84% knew diet was important. Prevalence of risk factors other than age were <  20%, except for senescence (38%) and alcohol use (40%). Utilization of specific therapies for osteoporosis was only 18% overall with a rate of 3% in men (p<0.01). In women, 50% and were taking calcium supplements compared with 15% men (p<0.001) and for multivitamins the figures were 57% and 33% respectively (p<0.05). These results show a high level of awareness and correct definition of osteoporosis in this cohort of patients. Specific therapy for prevention or treatment of osteoporosis was inappropriately low in the face of high risk. This study highlights the care gap in osteoporosis in seniors and the need for increased physician involvement in patient education and treatment. Proactive treatment requests from patients need to be encouraged, especially with the future demographic shift. Received: 3 August 2000 / Accepted: 20 December 2000  相似文献   
63.
Ohne Zusammenfassung  相似文献   
64.
Abstrakt 1. Hinsichtlich der Frage der Anerkennung einer Heilmethode kommt es nicht darauf an, ob eine Methode von der überwiegenden Mehrheit der sogenannten Schulmediziner anerkannt wird, aber auch nicht, ob die betreffende Methode „therapieimmanent“, also von denjenigen, die diese Methode entwickelt haben oder sie anwenden, als wirksam eingesch?tzt wird. Entscheidend ist vielmehr auf die Anerkennung derjenigen Personen abzustellen, die sich von dritter Seite als Wissenschaftler in einem wissenschaftlichen Verfahren mit der Frage der Wirksamkeit der betreffenden Methode auseinandergesetzt haben. 2. Der Wirkmechanismus der Bioresonanztherapie ist nach strengen naturwissenschaftlichen Untersuchungen nicht zu erkl?ren. Diese Methode ist jedoch von der Hufelandgesellschaft, die sich aus 25 ?rztegesellschaften zusammensetzt, die allesamt auch Naturheilverfahren betreiben, anerkannt. (Leits?tze des Bearbeiters)  相似文献   
65.
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67.
Kitchen  E; Rossi  AG; Condliffe  AM; Haslett  C; Chilvers  ER 《Blood》1996,88(11):4330-4337
Exposure of neutrophils to agents such as lipopolysaccharide, tumor necrosis factor-alpha (TNF-alpha), and the granulocyte-macrophage colony-stimulating factor causes a major upregulation of subsequent agonist-induced NADPH oxidase activation. This priming effect is a prerequisite for neutrophil-mediated tissue damage and has been widely considered to be an irreversible process. We have investigated the potential for neutrophils to recover from a priming stimulus by studying the effects of platelet-activating factor (PAF). PAF did not stimulate respiratory burst activity directly, but caused a rapid (maximal at 10 minutes) and concentration-dependent (EC50 50.2 nmol/L) increase in N-formyl-methionyl-leucyl-phenylalanine (fMLP)-stimulated superoxide anion release. At time-points > 10 minutes, this priming effect spontaneously declined, with return to basal levels of fMLP- stimulated superoxide anion generation by 120 minutes. An identical priming time-course was observed with N-methyl carbamyl PAF, a nonmetabolizable analogue of PAF, indicating that the transient nature of PAF-induced priming was not secondary to PAF metabolism. Two structurally diverse PAF receptor antagonists (UK-74,505 and WEB 2086), added 10 minutes after PAF addition, increased the rate of decay of the priming effect. In contrast, TNF-alpha-induced priming, which was of a similar magnitude to that observed for PAF, was slower to evolve (maximal at 30 minutes) and remained constant for at least 120 minutes. The reversible nature of PAF-induced priming was confirmed by demonstrating that PAF-, but not TNF-alpha-, induced cell polarization (shape change) and CD11b-dependent neutrophil binding of albumin-coated latex beads was also transient, with return to basal, unstimulated levels by 120 minutes. Furthermore, cells that had spontaneously deprimed following PAF exposure retained their capacity to be fully reprimed by a subsequent addition of either PAF or TNF-alpha. These data imply that neutrophil priming is not an irreversible event: the demonstration of a cycle of complete priming, depriming, and repriming offers the potential for functional recycling of neutrophils at sites of inflammation.  相似文献   
68.
To investigate bone turnover in patients with seronegative spondylarthropathy, a bone formation marker, type 1 procollagen carboxy- terminal propeptide (P1CP), and resorption markers, the pyridinium cross-links of collagen [urinary free (f) PYR and DPYR], were measured. The median f-PYR, f-DPYR and P1CP (+/-interquartile range) were 15.8 (6.00) nmol/mmol creatinine, 3.8 (2.2) nmol/mmol creatinine and 101.5 (38) micrograms/1, respectively. There was a positive correlation between resorption markers and acute-phase reactants such as C-reactive protein (r = 0.42 for PYR, r = 0.42 for DPYR, P < 0.05), and a negative correlation observed between P1CP and the erythrocyte sedimentation rate (r = -0.64, P < 0.05). In the subgroup of patients with an elevated CRP concentration, the concentration of PYR and DPYR was significantly increased (f-PYR 25.7 vs 15.8 and f-DPYR 6.6 vs 3.8, P < 0.01 for f-PYR, P < 0.05 for f-DPYR). This study suggests than an elevation in acute-phase response in patients with seronegative spondylarthropathy is associated with increased concentration of bone resorption markers with a tendency for reduction in bone formation markers. This may represent uncoupling of bone formation and resorption, leading to bone loss in such patients.   相似文献   
69.

Objective

To outline the efficacy and risks of bisphosphonate therapy for the management of osteoporosis and describe which patients might be eligible for bisphosphonate “drug holiday.”

Quality of evidence

MEDLINE (PubMed, through December 31, 2012) was used to identify relevant publications for inclusion. Most of the evidence cited is level II evidence (non-randomized, cohort, and other comparisons trials).

Main message

The antifracture efficacy of approved first-line bisphosphonates has been proven in randomized controlled clinical trials. However, with more extensive and prolonged clinical use of bisphosphonates, associations have been reported between their administration and the occurrence of rare, but serious, adverse events. Osteonecrosis of the jaw and atypical subtrochanteric and diaphyseal femur fractures might be related to the use of bisphosphonates in osteoporosis, but they are exceedingly rare and they often occur with other comorbidities or concomitant medication use. Drug holidays should only be considered in low-risk patients and in select patients at moderate risk of fracture after 3 to 5 years of therapy.

Conclusion

When bisphosphonates are prescribed to patients at high risk of fracture, their antifracture benefits considerably outweigh their potential for harm. For patients taking bisphosphonates for 3 to 5 years, reassess the need for ongoing therapy.Postmenopausal osteoporosis is characterized by accelerated loss of bone mass and deterioration of bone architecture, leading to increased fracture risk.1 Osteoporotic fractures decrease personal independence,2 increase morbidity,35 and shorten life6,7; thus, their prevention is paramount.Aminobisphosphonates (alendronate, risedronate, and zoledronic acid) are first-line therapies for the prevention of fracture in high-risk individuals.8 Aminobisphosphonates might also increase survival in ways at least partially independent of their contribution to decrease in fracture incidence.911 While the antifracture efficacy and relative safety of the aminobisphosphonates have been well established in clinical trials,1216 there have been concerns that prolonged use of these drugs might increase the risk of rare, but serious, adverse events.1721  相似文献   
70.
Baker  DE; Silver  TM; Coran  AG; McMillin  KI 《Radiology》1986,161(2):341-344
At the authors' medical center, most patients with postappendectomy fluid collections are treated conservatively. Thirty-two (15%) of 216 children underwent postoperative sonography following appendectomies. In ten patients (31%), a total of 16 fluid collections were found on the initial postoperative sonogram. In the seven patients (70%) whose fluid collections were confined to the pelvis, the condition was treated conservatively and it resolved in 2-9 weeks. In three patients, fluid collections required surgical drainage and proved to be abscesses. In two of the three patients, abscesses were multiple and widely distributed in the abdomen, and the patients were clinically ill. The authors conclude that clinically symptomatic fluid collections develop postoperatively in approximately 5% of children who have undergone appendectomy for acute appendicitis and that the size and course of the fluid collection can be objectively monitored using sonography. Such fluid collections confined to the pelvis ultimately resolve with conservative, nonoperative therapy, although resolution may take up to 2 months.  相似文献   
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