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51.
Halm-Zielke Instrumentation (HZI) was developed to eliminate the disadvantage of ventral derotation spondylodesis (VDS)-Zielke in terms of lack of primary stability and in order to simplify sagittal plane control. Within a prospective clinical trial started in 1993, we have studied whether HZI fulfills these demands. HZI is an anterior double-rod system with a two screw per vertebral body fixation. The longitudinal components consist of a threaded VDS rod and a solid rod, which are attached to a hinge-conducted lid plate. Twenty-nine consecutive patients with idiopathic scoliosis and curves ranging from 36 degrees to 92 degrees were treated with HZI. The follow-up period ranged from 1 to 4 years. Correction of the frontal plane within the instrumented levels averaged 71.6% and 70.5% postoperatively and at follow-up, respectively. Derotation averaged 53.7% and mean correction of the tilt of the lowest instrumented vertebra was 69.5% at final follow-up. Thoracolumbar kyphosis was present in eight patients and was always completely corrected from +18.8 degrees to 3.3 degrees on average. One implant-related complication involved a screw breakage 18 months postoperatively without adverse effects. There was no case of pseudoarthrosis. All patients were mobilized without any additional external immobilization in terms of a brace or cast, and were allowed to go swimming for physiotherapeutical purposes immediately after wound healing. This study proves that HZI is a primary stable implant to perform VDS. Implant-related disadvantages typical of VDS are eliminated. Thereby, the period of rehabilitation is shortened by many months due to avoidance of cast and brace treatment.  相似文献   
52.
Phosphorus-31 nuclear magnetic resonance spectroscopy was used to evaluate the stability of carboxycyclophosphamide (CXCP) and carboxyifosfamide (CXIF) in human urine at pH 7.0 and 5.5 at 25°, 8°, −20°, and −80 °C. At 25 °C and pH 7.0, CXCP and CXIF are relatively stable (≈10% degradation in 24 h). In contrast, they are much less stable at pH 5.5 (≈80% degradation of CXIF and ≈50% degradation of CXCP in 24 h). The rate of degradation of CXCP and CXIF was a function of the storage temperature of the urine samples but, even at −80 °C, was not negligible: ≈30% degradation for CXCP irrespective of pH and ≈40% and 50% degradation for CXIF at pH 7.0 and 5.5, respectively, after storage for 6 months. CXCP was more stable than CXIF at either pH (7.0 or 5.5) and at all storage temperatures (8°, −20°, or −80 °C) of the urine samples. CXCP and CXIF were more stable at pH 7.0 than at pH 5.5, although this difference fell with decreasing temperatures to be almost negligible at −80 °C. To ensure a true estimate of CXCP and CXIF levels, urine samples must be frozen and stored at −80 °C within a few hours of micturition. CXCP and CXIF assays should also be carried out within 2 months and 1 month of storage, respectively. Received: 13 July 1996 / Accepted: 20 January 1997  相似文献   
53.
Closure of the surgical defect immediately after partial maxillectomy is the treatment of choice. The advantages are: maintaining facial contour, rapid re-establishment of speech, swallowing and mastication. A number of methods for the fixation of the immediate obturator in patients without teeth have been described. A new technique is reported where a transnasal wire holds the existing denture in position after partial maxillectomy. The method has been carried out on 7 patients with sino-nasal cancer during the period 1978-1994. The advantages of the technique are that the wire acts as an axis of rotation which together with the sponge in the cavity provide good stability of the denture. There is minimal preoperative laboratory work and simplification in replacing the surgical dressing.  相似文献   
54.
PURPOSE: Cloretazine (VNP40101M) is a novel sulfonylhydrazine alkylating agent with significant antileukemia activity. A phase I study of cloretazine combined with cytarabine (1-beta-d-arabinofuranosylcytosine, ara-C) was conducted in patients with refractory disease. DESIGN: Ara-C was given i.v. at a fixed dose of 1.5 gm/m(2)/d by continuous infusion for 4 days (patients ages <65 years at time of diagnosis) or 3 days (patients ages > or =65 years). Cloretazine was given i.v. over 15 to 60 minutes on day 2 at a starting dose of 200 mg/m(2), with escalation in 100 mg/m(2) increments in cohorts of three to six patients until a maximum tolerated dose was established. The DNA repair enzyme O(6)-alkylguanine DNA alkyltransferase (AGT) was measured at baseline. RESULTS: Forty patients, including 32 with acute myeloid leukemia, received 47 courses of treatment. Complete responses were seen at cloretazine dose levels of > or =400 mg/m(2) in 10 of 37 (27%) evaluable patients, and in this patient subset, AGT activity was significantly lower in patients that responded to treatment than in patients who did not (P < or = 0.027). Dose-limiting toxicities (gastrointestinal and myelosuppression) were seen with 500 and 600 mg/m(2) of cloretazine combined with the 4-day ara-C schedule but not seen with the 3-day schedule. CONCLUSION: The recommended cloretazine dose schedule for future studies is 600 mg/m(2) combined with 1.5 gm/m(2)/d continuous infusion of ara-C for 3 days. The cloretazine and ara-C regimen has significant antileukemic activity. AGT activity may be a predictor of response to cloretazine.  相似文献   
55.
Bartonella henselae, the causative agent of cat‐scratch disease, has been recognized to be responsible for a broad range of clinical syndromes. We report the case of a patient with disseminated B. henselae infection mimicking Langerhans cell histiocytosis at presentation and its successful management with neurosurgery, prolonged antibacterial therapy, and observation.  相似文献   
56.
RAS genes encode a family of 21 kDa proteins that are an essential hub for a number of survival, proliferation, differentiation and senescence pathways. Signaling of the RAS-GTPases through the RAF-MEK-ERK pathway, the first identified mitogen-associated protein kinase (MAPK) cascade is essential in development. A group of genetic syndromes, named “RASopathies”, had been identified which are caused by heterozygosity for germline mutations in genes that encode protein components of the RAS/MAPK pathway. Several of these clinically overlapping disorders, including Noonan syndrome, Noonan-like CBL syndrome, Costello syndrome, cardio-facio-cutaneous (CFC) syndrome, neurofibromatosis type I, and Legius syndrome, predispose to cancer and abnormal myelopoiesis in infancy. This review focuses on juvenile myelomonocytic leukemia (JMML), a malignancy of early childhood characterized by initiating germline and/or somatic mutations in five genes of the RAS/MAPK pathway: PTPN11, CBL, NF-1, KRAS and NRAS. Natural courses of these five subtypes differ, although hematopoietic stem cell transplantation remains the only curative therapy option for most children with JMML. With whole-exome sequencing studies revealing few secondary lesions it will be crucial to better understand the RAS/MAPK signaling network with its crosstalks and feed-back loops to carefully design early clinical trials with novel pharmacological agents in this still puzzling leukemia.  相似文献   
57.
Patients with monoclonal gammopathy of undetermined significance (MGUS) have a higher risk for the development of concomitant primary cancers such as multiple myeloma (MM) and myelodysplastic syndrome (MDS). We report the case of patient initially suffering from MGUS of the IgG lambda subtype for more than 10 yr, which evolved to MM and MDS with deletion (5q) with severe pancytopenia. Due to pancytopenia, he received dose‐reduced treatment with lenalidomide and dexamethasone. He achieved an ongoing transfusion independency after about 1 month of treatment. Bone marrow taken 14 months after start of treatment showed a complete cytogenetic response of the del(5q) clone and a plasma cell infiltration below 5%. In contrast to the development of MM in MGUS patients, the subsequent occurrence of MDS after diagnosis of MGUS is infrequent. Moreover, the biological association of MDS with MGUS is not sufficiently understood, but the non‐treatment‐related occurrence supports the pathogenetic role of pre‐existing alterations of stem cells. Here, we summarize data on concomitant MDS and MGUS/MM with particular emphasis on molecular aspects.  相似文献   
58.
Conflict monitoring and motor inhibition are engaged in the performance of complex tasks. The midcingulate cortex (MCC) has been suggested to detect conflicts, whereas the right inferior frontal cortex (IFC) seems to be of relevance for the inhibition process. The current experiment investigates the neural underpinnings of their interplay via a modified flanker paradigm. Conflict was manipulated by the congruency of flanking stimuli relative to a target (congruent vs. incongruent) and motor inhibition by a within‐trial response change of the initiated response (keep response vs. stop‐change). We used event‐related functional magnetic resonance imaging, decomposition with high model order ICA, and single trial analysis to derive a functional parcellation of the whole‐brain data. Results demonstrate the segmentation of the MCC into anterior and posterior subregions, and of the IFC into the pars opercularis, pars triangularis, and pars orbitalis. The pars opercularis and pars triangularis of the right IFC constituted the foundation of inhibition‐related networks. With high conflict on incongruent trials, activity in the posterior MCC network, as well as in one right IFC network was observed. Stop‐change trials modulated both the MCC as well as networks covering extended parts of the IFC. Whereas conflict processing and inhibition most often are studied separately, this study provides a synopsis of functionally coupled brain regions acting in concert to enable an optimal performance in situations involving interference and inhibition. Hum Brain Mapp, 2013. © 2012 Wiley Periodicals, Inc.  相似文献   
59.
60.
Despite the fact that Member States and many citizens of the EU like to keep healthcare a foremost national competence and the EU treaties state that Member States remain primarily responsible for the organization and delivery of health care services, the European Union (EU) has expanded its involvement in healthcare policy over the last twenty years. Based on interviews and document and literature analysis we show that the scope of EU involvement has widened from public health and access to care, to quality of care. In this paper we concentrate on the latter. Focusing on the recent EU initiatives regarding the quality systems of the Member States and the quality of services, this paper shows how the depth of EU interference has increased from sharing information to standardization and even to the first signs of enforcement. We argue that at this stage, reflection on the feasibility and desirability of the EU's involvement is clearly needed, also considering the differences in quality of care policies between and within EU Member States. Both arguments in favour and against further EU involvement are discussed in this paper.  相似文献   
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