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91.
This is a report about six cases of replacement of the proximal femur by a cementless special prosthesis in modular system done in the Unfallkrankenhaus Wien-Meidling. One of the patients suffered by a lymphoma, three others had fractures caused by bone metastasis. One was a pertrochanteric fracture complicated by osteoporosis, and finally one fracture of the femur preceded by an insufficient implantation of a semitotal hip replacement. The hipsocket was supplied four times by a cementfree Polyäthylensocket, in one case a CLW-ring was implanted. Investigation showed that after a little more than two months the stump of femur became porous and by an average of eleven months the prosthesis was covered by bone. The complications were in one case an incomplete fracture of the diaphysis and in another case a luxation for three times. There are several indications for a tumor prosthesis: 1. Primary and secondary malignant tumors. 2. Bone metastasis with or without fractures. 3. Comminuted fractures complicated by various factors, e. g. osteoporosis. 4. Loosening of prosthesis with poor bone conditions or failed implantation of a standard prosthesis. Although the successes seem to be quite promisingly, this method should be applied in a quite differentiated way, as any retreat is nearly impossible, once started.  相似文献   
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We surveyed a random sample (n = 75) of doctors and dentists at University College Hospital, Ibadan, Nigeria. They were offered anonymous testing for hepatitis B surface antigen (HBsAg), hepatitis Be antigen (HBeAG), antibodies to hepatitis B core antigen (anti-HBc) and to hepatitis C virus (anti-HCV), by enzyme immunoassay. The results suggest a high prevalence of hepatitis B virus (HBV) with a high potential of transmissibility, as well as a high prevalence of HCV infection. The majority of the doctors and dentists use universal precaution for protection against viral hepatitis on < 50% of the occasions when they carry out procedures on their patients. Infection with HBV was associated with type of specialty (surgeons, dentists) and lack of HBV vaccination (p < 0.05). After logistic regression, these factors were independently associated with HBV infection (p < 0.05). Sixty (80%) had not received prior HBV vaccination. Unvaccinated personnel were more likely to be surgeons, dentists, < 37 years of age, and have fewer years of professional activity (p < 0.05). After logistic regression, only fewer years of professional activity remained independently associated with lack of vaccination (p < 0.05). To reduce the occupational exposure of HBV, universal precautions must be rigorously adhered to when the doctors and dentists carry out procedures on their patients, and all health-care workers should be vaccinated with HBV vaccine and the HCV vaccine, when it becomes available.   相似文献   
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SUMMARY Although primary hepatocellular carcinoma (PHC) is quite common in adults in Africa, it is very rare in those under 25. The clinical diagnosis is usually straightforward by the time patients present and it is unusual to encounter differential diagnostic problems. We report an unusual clinical manifestation of PHC at the very young age of 15 years. The case presented clinically as a septicaemia-like illness that was initially thought to be typhoid. The patient died within 72h of presentation and the true diagnosis was only made at post-mortem. This case simultaneously highlights several problems commonly encountered in medicine in the developing world: late presentation, self-medication, and investigative and diagnostic difficulties related to inadequate facilities.  相似文献   
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Precursor B-cell acute lymphoblastic leukemias (B-ALLs) have been shown to be oligoclonal at the Ig heavy-chain (IgH) gene level in up to 40% of cases by Southern blot hybridization. In contrast, oligoclonality as deduced from diversity of T-cell receptor (TcR)-delta gene rearrangements of the immature types (ie, V delta 2-D delta 3, D delta 2-D delta 3) has not been reported, so far. We detected oligoclonality characterized by the coexistence of different junctional regions of identical V delta 2-D delta 3 rearrangements in four childhood precursor B-ALLs. No variation was found in the IgH gene status. Therefore, we define these populations as subclones. Two leukemias displayed the variants in an unequal proportion. In the other two leukemias, for which similar quantities of the coexisting rearrangements were detected, single cell-nuclei polymerase chain reaction (PCR) showed two separate leukemic populations. Subclone formation could not be demonstrated by Southern blot hybridization, but was detectable after PCR amplification of the V delta 2-D delta 3 rearrangement and separation by polyacrylamide gel electrophoresis. The variants arose independently from each other, as deduced from their individual sequences. Using subclone-specific oligonucleotides for hybridization to amplified DNA obtained at diagnosis and during follow- up from bone marrow samples, we demonstrate, (1) specificity of all subclone-deduced probes, (2) that one residual leukemic cell can be detected in 10(4) to 10(5) normal mononuclear cells in a semiquantitative assay, and (3) that none of the subclones persisted after induction therapy. We propose that in a leukemic cell population, TcR-delta gene diversity arises after rearrangements of the IgH genes resulting in apparent clonality at the IgH gene level. However, cells are oligoclonal, if the TcR-delta gene rearrangements are considered. As various subclones may respond differently to chemotherapy, they may hamper the detection of minimal residual disease. Therefore, we use all subclone-specific oligonucleotides for hybridization to amplified DNA from follow-up samples.  相似文献   
100.
Mammalian mitogenomic relationships and the root of the eutherian tree   总被引:28,自引:0,他引:28  
The strict orthology of mitochondrial (mt) coding sequences has promoted their use in phylogenetic analyses at different levels. Here we present the results of a mitogenomic study (i.e., analysis based on the set of protein-coding genes from complete mt genomes) of 60 mammalian species. This number includes 11 new mt genomes. The sampling comprises all but one of the traditional eutherian orders. The previously unrepresented order Dermoptera (flying lemurs) fell within Primates as the sister group of Anthropoidea, making Primates paraphyletic. This relationship was strongly supported. Lipotyphla ("insectivores") split into three distinct lineages: Erinaceomorpha, Tenrecomorpha, and Soricomorpha. Erinaceomorpha was the basal eutherian lineage. Sirenia (dugong) and Macroscelidea (elephant shrew) fell within the African clade. Pholidota (pangolin) joined the Cetferungulata as the sister group of Carnivora. The analyses identified monophyletic Pinnipedia with Otariidae (sea lions, fur seals) and Odobenidae (walruses) as sister groups to the exclusion of Phocidae (true seals).  相似文献   
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