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71.
The present study is divided into 2 parts: The first explains the concept of stimulating plate therapy at the Muenster Clinic and the second presents a longitudinal study of mouth and tongue posture in trisomy 21 children treated with this concept.47 children underwent a pre-treatment examination (Rec1), and 38 attended a first follow-up examination (Rec2) after an average of 4 months of stimulating plate treatment. The second follow-up examination (Rec3) was on average 53 months after the end of treatment and covered 18 patients. Data acquisition was based on standardized parent questionnaires and standardized clinical examination records. Rec2 showed in part a highly significant improvement in orofacial appearance. These results were confirmed by the parent interview, according to which the mouth and tongue posture improved in 76.3% of the children during the time they were wearing the plate. Even when the plate was not in place, the result remained stable in 65.8% of the patients. Up to Rec3, further improvement was recorded in some results. The symptoms: mouth mostly wide open and tongue mostly protruding way over lips were reduced. The number of children whose tongue was mostly in the oral cavity increased correspondingly.At Rec3, the parents also rated the mouth posture in 88.9% and the tongue posture in 77.7% of the children as stable or further improved.It can be concluded from the results of this study that stimulating plate treatment in combination with physiotherapy provides a long-term improvement in the mouth and tongue posture of children with Down's syndrome.  相似文献   
72.
BACKGROUND: The "comet assay" has become an interesting and a very useful tool for the analysis of the induction and amount of DNA damage in single cells thus offering the opportunity to measure the effectiveness of DNA repair. On the basis of the Ostling and Johanson protocol we have developed a modified method with increased sensitivity and high reproducibility. MATERIAL AND METHODS: Human tumor cells or isolated human peripheral blood lymphocytes were analyzed in the experiments. The amount of DNA damage and the effectiveness of DNA repair was measured after X-irradiation using the "comet assay" technique. RESULTS: In this presentation the influences of different methodological factors like agarose concentration, buffer pH, electrophoresis time, electric field strength on the applicability of the "comet assay" are described in detail and optimum conditions for "comet assay" experiments have been evaluated. Additionally the authors will show a comparison of different fluorescent DNA dyes pointing out their advantages or disadvantages for "comet" analysis. The usefulness of this technique and its capabilities are exemplified by showing DNA repair kinetics of human lymphocytes of different healthy or radiosensitive donors after in-vitro irradiation with 2 Gy X-rays. CONCLUSIONS: This paper presents data on the optimization and standardization of the original "comet assay" leading to an extremely fast and practicable protocol in the field of single cell gel electrophoresis. After irradiation with 0.1 Gy an increase in the amount of DNA damage can be measured with high statistical significance and the DNA repair capacity of individual cells after X-ray doses of 2 Gy can be analyzed with high reproducibility. The results comparing DNA repair capacities of different donors point out that the "comet assay" may have the potential for the estimation of individual radiosensitivity.  相似文献   
73.
In the region of Basel in Switzerland 43 assisted suicides were registered between 1992 and 1997, eight percent of all suicides in the region. Assisted suicide was administered by the help-to-die society Exit. There was a psychiatric history in six of the suicides. Four of them suffered of serious physical illness as well. The analyses of these six suicides focuses on the conditions of assisted suicide in people with mental illness and the ethical problems arising.  相似文献   
74.
 · Background: A prospective study was undertaken to determine the transcorneal penetration of three topically applied fluoroquinolones into aqueous humor. · Methods: Cataract patients (n=224) preoperatively received topically applied gyrase inhibitors (0.3% ciprofloxacin, 0.3% norfloxacin, 0.3% ofloxacin) in two different application modes. In application mode I, patients received on the day before operation 3×1 eye drop at 2-h intervals, and on the day of operation 3 drops at 1-h intervals. In application mode II, patients received 9 drops at 15-min intervals on the day of operation only. Just before cataract surgery 50–100 μl aqueous humor was aspirated and stored at –80 °C. The HPLC method was used for measuring the concentration. · Results: The highest concentrations of all tested antibiotics were measured after the mode of application in which one drop was given every 15 min between 06:00 and 08:00 hours before operation. In this mode, ciprofloxacin achieved a mean aqueous level of 379.8±327.8 μg/l (range 33–1388 μg/l), norfloxacin 182.1±118.1 μg/l (range 38–480 μg/l) and ofloxacin 563.9±372.1 μg/l (range 64–1455 μg/l). These mean concentration are all above the MIC90 of gram-negative bacteria like Proteus mirabilis and Escherichia coli. In some cases the concentrations of ciprofloxacin and ofloxacin, but never norfloxacin, reached therapeutic values above the MIC90 of Staphylococcus aureus and Staphylococcus epidermidis · Conclusions: The mean concentration value of 0.3% ciprofloxacin and of 0.3% ofloxacin in the aqueous humor reached the MIC90 values of the frequently occurring gram-positive and gram-negative bacteria. Of the currently available topical fluoroquinolones, ofloxacin achieved the highest aqueous humor concentration. Considering the higher antimicrobial activity of ciprofloxacin, both ciprofloxacin and ofloxacin may be useful ophthalmic agents in antibacterial management, but they are not efficient against Streptococcus pneumoniae and Pseudomonas aeruginosa. Received: 8 September 1997 Revised version received: 19 March 1998 Accepted: 8 April 1998  相似文献   
75.
Intraocular silicone lenses in silicone oil: an experimental study   总被引:4,自引:0,他引:4  
Background: To evaluate a potential effect of silicone oil on flexible silicone intraocular lenses, four lenses (STAAR AA-4203) were stored in silicone oil under sterile conditions for periods between 1 month and 3 years. Method: The edge and surface of the lenses were examined by scanning electron micrography and the findings compared with a lens of the same model which had been stored in Ringer's solution for 2 years. Results: After 1 year of silicone oil exposure, droplets of different sizes adherent to the surface of the lens were found. These changes proceeded to a wave-like appearance of the surface after 2 and 3 years of storage, so that a continuous layer of silicone oil polymers is probably covering the intraocular lens. Conclusion: Optical interference has to be considered a possibility if it turns out that the droplets cannot be removed during silicone oil evacuation. Consequently silicone intraocular lenses without hydrophilic preparation of the surface should not be implanted in eyes undergoing combined anterior and posterior segment surgery with silicone oil tamponade or in eyes with high risk for vitreoretinal complications.The authors state that they have no proprietary interest in the marketing of the products mentioned herein or competing products  相似文献   
76.
Yttrium-90 is used for palliative therapy for the treatment of skeletal metastases, but because it is a pure - emitter, data on the pharmacokinetics and radiation doses to metastases and unaffected organs are lacking. To obtain such data, the present study employed yttrium-86 as a substitute for90Y, with detection by positron emission tomography (PET). The study compared the properties of two different86Y complexes —86y-citrate and86Y -ethylene diamine tetramethylene phosphonate (EDTMP) — in ten patients with prostatic cancer who had developed multiple bone metastases (the ten patients being divided into two groups of five). Early dynamics were measured up to 1 h post injection (p.i.) over the liver region, followed by subsequent whole-body PET scans up to 3 days p.i. Absolute uptake data were determined for normal bone, bone metastases, liver and kidney. Radiation doses were calculated according to the MIRD recommendations. Based on the pharmacokinetic measurements of the distribution of the86Y complexes, it was possible to calculate radiation doses for the bone metastases and the red bone marrow delivered by complexes containing90Y. In 1 cm3 of bone metastasis, doses of 26±11 mGy/MBq and 18±2 mGy/MBq were determined per MBq of injected90Y- citrate and90Y- EDTMP, respectively. The doses to the bone marrow were 2.5±0.4 mGy/MBq for90Y- citrate and 1.8±0.6 mGy/MBq for90Y-EDTMP.86Y and PET provide quantitative information applicable to the clinical use of90Y. This method may also be useful for the design of other90Y radiopharmaceuticals and for planning radiotherapy dosages.  相似文献   
77.

Introduction

The reflex sympathetic dystrophy (RSD) syndrome usually shows a distally generalized distribution pattern of symptoms. Here we report a case with a distally localized form of RSD.

Patient and methods

In a 53-year-old woman, following a local lesion in the nail bed of the left thumb, a neuroma developed at the side of the lesion during the next half year. She was finally operated upon. Following that intervention, a complex and painful clinical syndrome occurred that for the most part affected only the thumb. A clinical neurological examination was carried out, including distal suprasystolic compression of the affected extremity after bandaging it (the so-called ischemia test). For diagnostic and therapeutic reasons, afterwards a conventional blockade of the ipsilateral stellate ganglion was applied.

Results

The clinical investigation showed a triad of autonomic (swelling, side difference of skin temperature, hyperhydrosis), motor (reduced movement ability, tremor) and sensory disturbances (spontaneous pain, allodynia), which nearly exclusively affected the entire left thumb. The spontaneous pain showed an orthostatic component (the pain being diminished or exaggerated when the extremity was elevated or lowered, respectively) and was suppressed by the ischemia test. Following the sympathetic block, all symptoms disappeared within one day (follow-up period: 5 months).

Conclusion

In contrast to the common clinical picture of RSD, with a distally generalized distribution of symptoms, the present case showed a so-called localized form of RSD, its triad affecting only the thumb with the lesion. Typically, the pain showed an orthostatic component and was suppressed by the ischemia test. The sympathetic block was immediately successful, proving the occurrence of this form of RSD for the first time. In similar clinical cases, this form of RSD should be considered as a differential diagnosis.  相似文献   
78.
The influence of cadmium (up to 10?4 M), fluoride (up to 10?4 M), and X-rays (up to 18.8 Gy) on different variables of preimplantation mouse embryos in vitro has been examined. The agents were applied either singly or in combination (0.94 Gy X-rays +3×10?7 M CdSO4 or CdF2; 0.94 Gy X-rays +3×10?6 M CdSO4 or CdF2). The following variables were determined:
  1. the microscopic visible development until 144 h post conceptionem (=144 h p.c.),
  2. the average cell numbers (48 h p.c., 56 h p.c., 72 h p.c., 96 h p.c., 120 h p.c., 144 h p.c.),
  3. the number of micronuclei (72 h p.c.),
  4. the distribution of cell nuclei within the cell cycle (72 h p.c.).
Nearly all results of the combination experiments correspond to the sum of the single effects. Only two values (out of about 40) significantly exceed the value obtained after addition of the single effects; both values lie within the envelope of additivity.  相似文献   
79.
The HLA class I antigen-processing machinery (APM) plays a crucial role in the generation of peptides from endogenously synthesized proteins and in their presentation to cytotoxic T lymphocytes. The potential role of defects of APM components in immune escape mechanisms used by malignant cells has prompted us to analyze their expression in renal cell carcinoma (RCC) lesions with special emphasis on TAP because of its critical role in the loading of HLA class I antigens with peptides. Immunohistochemical staining of 51 formalin-fixed RCC lesions and autologous normal renal epithelium detected transporter associated with antigen processing (TAP)1 and tapasin deficiencies in 63 and 80% of the tumor lesions. Impaired low molecular weight protein (LMP)2 and LMP7 expression was found in 73 and 33% of the RCC lesions analyzed, respectively. In contrast to the high frequency of APM component down-regulation, HLA class I heavy chain and beta(2)-microglobulin defects were detected in only 12 and 10% of the lesions, respectively. Concomitant TAP1 and LMP2 deficiencies were found in approximately 57% of RCC lesions, whereas a coordinated down-regulation of all APM components occurred only in 5% of the tumor specimens analyzed. The presence of APM defects was independent of tumor stage and grade but varied significantly among the RCC subtypes. TAP abnormalities do not appear to be attributable to structural alterations because no mutations in TAP1 were detected in TAP1-deficient RCC lesions. These data suggest that TAP defects in RCC lesions are caused by regulatory abnormalities. Therefore, T-cell-based immunotherapy may benefit from the administration of cytokines that up-regulate TAP expression.  相似文献   
80.
PURPOSE: To determine demographic data and define prognostic factors for long-term outcome in patients presenting with high-grade osteosarcoma of bone with clinically detectable metastases at initial presentation. PATIENTS AND METHODS: Of 1,765 patients with newly diagnosed, previously untreated high-grade osteosarcomas of bone registered in the neoadjuvant Cooperative Osteosarcoma Study Group studies before 1999, 202 patients (11.4%) had proven metastases at diagnosis and therefore were enrolled onto an analysis of demographic-, tumor-, and treatment-related variables, response, and survival. The intended therapeutic strategy included pre- and postoperative multiagent chemotherapy as well as aggressive surgery of all resectable lesions. RESULTS: With a median follow-up of 1.9 years (5.5 years for survivors), 60 patients were alive, 37 of whom were in continuously complete surgical remission. Actuarial overall survival rates at 5 and 10 (same value for 15) years were 29% (SE = 3%) and 24% (SE = 4%), respectively. In univariate analysis, survival was significantly correlated with patient age, site of the primary tumor, number and location of metastases, number of involved organ systems, histologic response of the primary tumor to preoperative chemotherapy, and completeness and time point of surgical resection of all tumor sites. However, after multivariate Cox regression analysis, only multiple metastases at diagnosis (relative hazard rate [RHR] = 2.3) and macroscopically incomplete surgical resection (RHR = 2.4) remained significantly associated with inferior outcomes. CONCLUSION: The number of metastases at diagnosis and the completeness of surgical resection of all clinically detected tumor sites are of independent prognostic value in patients with proven primary metastatic osteosarcoma.  相似文献   
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