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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   
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The histologic distinction between peritoneal epithelioid mesotheliomas and serous carcinomas diffusely involving the peritoneum may be difficult, but it can be facilitated by the use of immunohistochemistry and electron microscopy. D2-40 and podoplanin are two recently recognized lymphatic endothelial markers that can be expressed in normal mesothelial cells and mesotheliomas. The purpose of this study is to compare the value of these new mesothelial markers with those that are commonly used for discriminating between mesotheliomas and serous carcinomas, and also to determine the current role of electron microscopy in distinguishing between these malignancies. A total of 40 peritoneal epithelioid mesotheliomas and 45 serous carcinomas of the ovary (15 primary, 30 metastatic to the peritoneum) were investigated for the expression of the following markers: D2-40, podoplanin, calretinin, keratin 5/6, thrombomodulin, MOC-31, Ber-EP4, B72.3 (TAG-72), BG-8 (Lewis(Y)), CA19-9, and leu-M1 (CD15). All 40 (100%) of the mesotheliomas reacted for calretinin, 93% for D2-40, 93% for podoplanin, 93% for keratin 5/6, 73% for thrombomodulin, 13% for Ber-EP4, 5% for MOC-31, 3% for BG-8, and none for B72.3, CA19-9, or leu-M1. All 45 (100%) serous carcinomas were positive for Ber-EP4, 98% for MOC-31, 73% for B72.3, 73% for BG-8, 67% for CA19-9, 58% for leu-M1, 31% for keratin 5/6, 31% for calretinin, 13% for D2-40, 13% for podoplanin, and 4% for thrombomodulin. After analyzing the results, it is concluded that Ber-EP4 and MOC-31 are the best negative mesothelioma markers for differentiating between epithelioid mesotheliomas and serous carcinomas. The best discriminators among the positive markers for mesotheliomas are D2-40, podoplanin, and calretinin. From a practical point of view, Ber-EP4 and MOC-31, in combination with calretinin, and/or D2-40 or podoplanin allow the differential diagnosis to be established between mesothelioma and serous carcinoma in nearly all instances. As a clear distinction could be made between these two malignancies in all of the cases in which electron microscopy was performed, this technique can be very useful in establishing the correct diagnosis when the immunohistochemical results are equivocal or further support of a diagnosis of either mesothelioma or serous carcinoma is needed.  相似文献   
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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   
4.
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   
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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   
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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   
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