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1.
Isolated patellofemoral arthritis is an increasingly recognized entity, and is usually associated with previous patellofemoral dysplasia or instability. Patellofemoral arthroplasty (PFA) has evolved significantly in recent years, both in terms of implant design and importantly in the understanding of appropriate patient selection. This review outlines the indications and investigations for PFA, provides a brief history of the development of contemporary implants, and presents the clinical outcomes for the prostheses most commonly used in the UK. In addition, it provides a detailed surgical technique for implantation of an onlay implant, with tips on how to optimize patellofemoral biomechanics and thus achieve a consistently good outcome. 相似文献
2.
M. R. D. Maslin S. K. Lloyd S. Rutherford S. Freeman A. King D. R. Moore K. J. Munro 《Journal of the Association for Research in Otolaryngology》2015,16(5):631-640
Individuals with sudden unilateral deafness offer a unique opportunity to study plasticity of the binaural auditory system in adult humans. Stimulation of the intact ear results in increased activity in the auditory cortex. However, there are no reports of changes at sub-cortical levels in humans. Therefore, the aim of the present study was to investigate changes in sub-cortical activity immediately before and after the onset of surgically induced unilateral deafness in adult humans. Click-evoked auditory brainstem responses (ABRs) to stimulation of the healthy ear were recorded from ten adults during the course of translabyrinthine surgery for the removal of a unilateral acoustic neuroma. This surgical technique always results in abrupt deafferentation of the affected ear. The results revealed a rapid (within minutes) reduction in latency of wave V (mean pre = 6.55 ms; mean post = 6.15 ms; p < 0.001). A latency reduction was also observed for wave III (mean pre = 4.40 ms; mean post = 4.13 ms; p < 0.001). These reductions in response latency are consistent with functional changes including disinhibition or/and more rapid intra-cellular signalling affecting binaurally sensitive neurons in the central auditory system. The results are highly relevant for improved understanding of putative physiological mechanisms underlying perceptual disorders such as tinnitus and hyperacusis. 相似文献
3.
Andreas G Schatzlein Bernd H Zinselmeyer Adurrahim Elouzi Christine Dufes Ya Tsz A Chim Clive J Roberts Martyn C Davies Avril Munro Alexander I Gray Ijeoma F Uchegbu 《Journal of controlled release》2005,101(1-3):247-258
Previously, the lower generation (DAB 8-generation 2 and DAB 16-generation 3) polypropylenimine dendrimers have been shown to be effective gene delivery systems in vitro. In the current work, we sought to: (a) test the effect of the strength of the carrier, DNA electrostatic interaction on gene transfer and (b) to study the in vivo gene transfer activity of these low molecular weight (<1687 Da) non-amphiphilic plain and quaternary ammonium gene carriers. Towards this aim, methyl quaternary ammonium derivatives of DAB 4 (generation 1), DAB 8, DAB 16 and DAB 32 (generation 4) were synthesised to give Q4, Q8, Q16 and Q32, respectively. Quaternisation of DAB 8 proved to be critical in improving DNA binding, as evidenced by data from the ethidium bromide exclusion assay and dendrimer-DNA colloidal stability data. This improved colloidal stability had a major effect on vector tolerability, as Q8-DNA formulations were well tolerated on intravenous injection while a similar DAB 8-DNA dose was lethally toxic by the same route. Quaternisation also improved the in vitro cell biocompatibility of DAB 16-DNA and DAB 32-DNA dendrimer complexes by about 4-fold but not that of the lower generation DAB 4-DNA and DAB 8-DNA formulations. In contrast to previous reports with non-viral gene delivery systems, the intravenous administration of DAB 16-DNA and Q8-DNA formulations resulted in liver targeted gene expression as opposed to the lung targeted gene expression obtained with the control polymer-Exgen 500 [linear poly(ethylenimine)] and a lung avoidance hypothesis is postulated. We conclude that the polypropylenimine dendrimers are promising gene delivery systems which may be used to target the liver and avoid the lung and also that molecular modifications conferring colloidal stability on gene delivery formulations have a profound effect on their tolerability on intravenous administration. 相似文献
4.
5.
RA O. Hempel 《Notfall & Rettungsmedizin》2007,10(5):367-371
Legal uncertainties for emergency vehicle drivers can be avoided when fundamental rules are established. In particular, differentiation of special rights and rights of way is essential. Inherent in both is the urgency necessary to save human lives. The right of way signaled by flashing blue lights and siren does not however justify traffic violations but signifies rather a request to other traffic participants. In contrast, special rights require no announcement and constitute a justifiable reason for traffic violations. Even so they do not allow that other traffic participants be endangered or harmed. Adherence to these basic principles can prevent legal misinterpretations as well as rigid adoption of inflexible standards of behavior. 相似文献
6.
RA Mag. Dr. C. Gepart 《Notfall & Rettungsmedizin》2007,10(4):289-292
Austria’s new Living Wills Act (Patientenverfügungsgesetz, or PatVG) that came into effect on 1st of June 2006, is the first law in Austria to regulate the controversial issue of living wills. The PatVG provides for a right to refuse future medical treatment by making an advance directive in the form of a living will that is either binding or “to be taken into consideration”. However, the establishment of a binding living will is governed by strict criteria as regards form and content, and both a medical doctor and a legal expert must be involved. Compliance with a living will is not allowed where there is a legal obligation to give medical treatment. There is also a legal obligation to give medical treatment in emergency situations where the time involved in looking for a living will could seriously endanger the health or the life of a patient. 相似文献
7.
Ohne Zusammenfassung 相似文献
8.
Both cyproterone acetate (CPA) and the gonadotrophin-releasing hormone
agonist (GnRHa) have been shown to be effective for the treatment of
hirsutism. We wished to compare the effectiveness of CPA in two standard
doses with GnRHa and add-back therapy and to compare the length of
remission after these treatments. A total of 60 hirsute hyperandrogenic
women was assigned to the following treatment groups: CPA 2 mg with 35
microg of ethinylestradiol for 21 days each month (Diane group), CPA 50 mg,
days 5-15, and ethinylestradiol 50 microg, days 5-25, each month (CPA
group) or Decapeptyl 3.75 mg i.m. every 28 days with the addition of
conjugated oestrogen 0.625 mg, days 1-21, and medroxyprogesterone acetate
10 mg, days 12-21 (GnRHa group). Hirsutism was graded by the
Ferriman-Gallwey-Lorenzo (FGL) index and anagen hair shaft diameters and
serum luteinizing hormone (LH) and testosterone were assessed before and
every 3 months during and after treatment. All women were treated for 1
year with 1 year follow-up. At baseline hirsutism and endocrine patterns
were similar in all groups. After one year of treatment, hirsutism
decreased in all groups but the changes were greater (P <0.05) in the
CPA and GnRHa groups than in the Diane group. Serum LH and testosterone
were lowest in the GnRHa group. After withdrawal, hirsutism increased
rapidly in the Diane and CPA groups and after 6 months, FGL scores and hair
shaft diameters were similar to pretreatment values. In the GnRHa group,
hirsutism increased more gradually and after 1 year of withdrawal, FGL
scores and hair diameters were significantly (P <0.05) less than
pretreatment values. Serum LH and testosterone increased rapidly in all
three groups reaching pretreatment values by 6 months. These data suggest
equal efficacy of the GnRHa and the high dose CPA regimen for the treatment
of hirsutism in hyperandrogenic women. GnRHa with add-back treatment
appears to result in a longer remission of hirsutism in comparison with
CPA.
相似文献
9.
10.
Maxillary sinusitis in adults: an evaluation of placebo-controlled double-blind trials 总被引:1,自引:0,他引:1
BACKGROUND: In general practice, acute sinusitis is frequently diagnosed
and treated with antibiotics. OBJECTIVE: This study aimed to determine the
evidence for the effectiveness of antibiotic treatment in acute maxillary
sinusitis in adults by assessing the methodological quality of
placebo-controlled double-blind randomized trials. METHOD: An evaluation by
four raters through a 35-item scoring-scale for internal and external
validity of all placebo-controlled double-blind randomized trials on acute
sinusitis found between January 1966 and July 1996. RESULTS: Eighty-five
trials were excluded because they were not placebo-controlled,
double-blind, randomized, or were carried out in patients with chronic
sinusitis or in children. The three remaining trials were performed in
different populations (one in general practice) between 1973 and 1978. Only
one study claimed superiority of antibiotic treatment. Different inclusion
criteria and major outcome measures were used by the authors. The
reliability of major outcome events was reported poorly or not at all and
in two studies outcome measures were clinically inappropriate. The studies
scored 30-62% of the maximum attainable score for internal validity and
10-20% for external validity. CONCLUSION: The effectiveness of antibiotic
treatment in acute maxillary sinusitis in a general practice population is
not based sufficiently on evidence.
相似文献