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151.
Schlu?folgerungen Aus der Me?wert-Verteilung der Grauwerte im Sonogramm lassen sich Kennwerte berechnen, die eine computergestützte sonographische Reifebeurteilung der Plazenta erm?glichen. Allerdings sind die Verteilungsparameter (Median, Varianz, Schiefe, Exze?) abh?ngig von den Ger?teparametern. Zuverl?ssiger ist die Berechnung von Kennwerten, die sich auf die strukturellen Eigenschaften des Sonogramms beziehen. Bei den hier dargestellten Untersuchungen k?nnen Kennwerte für den Kontrast bzw. für die Ansammlung gleichartiger Grauwerte um einen bestimmten Punkt die sonographische Beurteilung der Plazenta optimieren. Damit erweitern sich die M?glichkeiten für die Zustandsdiagnostik der intrauterinen Lebensbedingungen.  相似文献   
152.
In a study of 972 women, sexual characteristics of 66 women with a cervical human papillomavirus infection (CHPI) were compared to the remaining study population. Among a number of sexual variables that were significantly correlated with CHPI were number of lifetime sexual partners, short partnerships, many recent partners, infidelity, casual travel sex, sexual début abroad, oral and anal sex, and sexual abuse. In multifactorial analyses four variables remained significantly correlated with CHPI, i.e., number of lifetime sexual partners, casual travel sex, sexual début abroad, and infidelity. It is concluded that CHPI shows most of the epidemiological characteristics of a sexually transmitted disease.  相似文献   
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154.
Purpose It was the aim of this study to investigate the efficacy, longevity, and safety of a new ab interno intervention for the treatment of primary open-angle glaucoma (POAG). Methods The previously described method of radiofrequency-mediated “sclerothalamotomy ab interno” was applied in 53 eyes of consecutive patients with POAG between April 2002 and July 2002. Average preoperative intraocular pressure (IOP) was 25.6±2.3 mmHg (range 18–48 mmHg). Sclerothalamotomies were carried out with a custom-made high-frequency dissection 19 G probe (tip 0.3×1 mm) applying bipolar current with a frequency of 500 kHz (tip temperature 130°C). Results After a follow-up period of 24 months, the average IOP was 15.0±1.6 mmHg (range 11–20 mmHg) (p<0.005). The average number of topical agents was 2.6±1.0 (range 1–5) preoperatively. Twenty-four months after surgery such agents were used in only five (9.6%) eyes and the average was 0.21±0.53 (range 0–2). Transient IOP elevation was observed in 12 of 53 eyes (22.6%) postoperatively. In all cases elevated IOP could efficiently be controlled with topical medication. In general, IOP dropped continuously over the course of the 6 months following surgery and then remained constant. Conclusions This study indicates that sclerothalamotomy ab interno is a safe and efficient surgical method for the treatment of POAG. Long-term results clearly demonstrate the longevity of IOP reduction.  相似文献   
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156.
BACKGROUND AND PURPOSE: Following preoperative radiotherapy prior to ablative surgery of squamous epithelial cell carcinomas of the head and neck region, wound-healing disorders occur. Previous experimental studies showed altered expression of transforming growth factor-(TGF-)beta isoforms following surgery in irradiated graft beds. Altered levels of TGF-beta(1) are reported to promote fibrosis and to suppress vascularization during wound healing, whereas expression of TGF-beta receptor-III (TGF-betaR-III) is associated with vascularization. The aim of the study was to analyze the influence of anti-TGF-beta(1) treatment on TGF-betaR-III-associated vascularization in the transition area between irradiated graft bed and graft. MATERIAL AND METHODS: Wistar rats (male, weight 300-500 g) underwent preoperative irradiation of the head and neck region with 40 Gy (four fractions of 10 Gy each; n = 16 animals). A free myocutaneous gracilis flap taken from the groin was then transplanted to the neck in all rats. The time interval between operation and transplantation was 4 weeks. Eight animals received 1 micro g anti-TGF-beta(1) into the graft bed by intradermal injection on days 1-7 after surgery. On days 3, 7, 14, 28, 56, and 120, skin samples were taken from the transition area between transplant and graft bed and from the graft bed itself. Immunohistochemistry was performed using the ABC-POX method to analyze the TGF-betaR-III and E-selectin expression. Histomorphometry was performed to analyze the percentage and the area of positively stained vessels. RESULTS: A significantly higher expression of TGF-betaR-III was seen in the irradiated and anti-TGF-beta(1)-treated graft bed in comparison to the group receiving preoperative irradiation followed by transplantation alone. The percentage of TGF-betaR-III positively staining capillaries from the total amount of capillaries in the anti-TGF-beta(1)-treated graft bed was higher than in the group irradiated only. The total area of capillaries was also higher in the TGF-beta(1)-treated group. CONCLUSION: Neutralizing of TGF-beta(1) activity in irradiated tissue undergoing surgery leads to a higher expression of TGF-betaR-III and increased vascularization. TGF-betaR-III seems to be associated with newly formed blood vessels during neovascularization in wound healing.  相似文献   
157.
The therapeutic concept of irradiation of the vessel wall for prevention of restenosis after endovascular procedures is based on increasing knowledge about the pathophysiology of the process leading to restenosis. There is until now only a limited number of studies concerning the use of brachytherapy (BT) in the peripheral circulation, which is in contrast to the already large experience in the coronary circulation. In the peripheral trials the radiation dose was administered by a remote afterloader using a gamma source. According to the available data, vascular BT is a promising technology with the potential to reduce the restenosis rate. The Vienna-2-Trial was the first randomised study to demonstrate the efficacy of endovascular BT for prophylaxis of restenosis after femoropopliteal percutaneous transluminal angioplasty. However, we have to await further supportive data from ongoing clinical trials before definitive recommendations can be given. Currently, endovascular BT seems already justified in patients with recurrent interventions or after long-segment femoropopliteal angioplasty because of the high risk of restenosis in these patients. The next years will demonstrate the ultimate role of endovascular BT in comparison to the rapidly evolving field of drug-eluting stents.  相似文献   
158.
159.
Summary Forty-four Parkinson patients (19 patients of the rigid-akinetic type, 13, of the rigid-akinetic-tremor type, and 12, of the tremor type) were included in a study in order to analyse correlations of the expression of the motor symptoms tremor, rigidity, akinesia, with other clinical parameters, computertomographic aspect of brain atrophy and psychometrically assessed cognitive parameters. Rigidity and akinesia are significantly positively correlated with the severity of motor dysability, stage of the disease, and brain atrophy, as is akinesia with a history of pharmacotoxic psychosis. Tremor is significantly negatively correlated with motor dysability, stage of the disease, and history of pharmacotoxic psychosis. Akinesia is correlated with visuomotor dysfunction (tested with Bender Gestalt Test) and rigidity with the depression score (Zung scale). The tremor type is favorable, the rigid-akinetic type unfavorable with respect to motor disability and psychosis.  相似文献   
160.
Summary Seventy-five diabetic and 40 nondiabetic subjects who where suffering from peripheral vascular disease were studied in order to determine whether the degree of the severity of their disease can be better calculated by Doppler ultrasound examinations of the peak velocity than by the systolic pressure of the peripheral bloodstream. In 46 examinations of normal controls the mean value of the peak velocity was 13.3±3.3 cm/s with a standard deviation of 15.4%±13.2% on one day and 16.1%±15.9% on different days. Considering patients with or without diabetes mellitus the velocity was significantly decreased in correlation to an increasing degree of severity of the vascular disease (P<0.001); however, the decrease was lower in diabetic than in nondiabetic subjects (6.9±2.8 vs 4.6±6.2,P<0.05). The systolic pressure hardly decreased, but remained higher in all stages of peripheral vascular disease of diabetics than in the nondiabetic subject (P<0.05 toP<0.005). There was a significant decrease of the systolic pressure only in diabetic subjects with the most advanced degree of the disease, i.e. stage IV (P<0.05).It is concluded from this study that Doppler ultrasound measurements of the peak velocity of the peripheral bloodstream are a useful parameter to calculate the degree of severity of the peripheral vascular disease. In addition, it is concluded than peak velocity is an even better prognostic indicator of peripheral vascular disease than is measurement of the systolic blood pressure at the feet.

Abkürzungen AVK periphere arterielle Verschlußkrankheit - USDI Ultraschall-Doppler-Index - MSBG maximale Blutströmungsgeschwindigkeit - HFV Herzfrequenzvariation  相似文献   
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