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31.
Axel  L; Summers  RM; Kressel  HY; Charles  C 《Radiology》1986,160(3):795-801
Respiratory and other regular motions during two-dimensional Fourier transform magnetic resonance imaging produce image artifacts consisting of local blurring and more or less regularly spaced "ghost" images propagating along the direction of the phase-encoding magnetic field gradient. The patterns of these ghost artifacts can be understood in terms of the technique of image production and basic properties of the discrete Fourier transform. This understanding permits, without respiratory gating, production of images of improved quality in body regions in which there is significant respiratory motion. In particular, the ghosts can be maximally separated from the primary image by choosing intervals between phase-encoding gradient pulse increments that are equal to one-half the respiratory period; they can be minimally separated by choosing an interval equal to the respiratory period. Increasing the number of signal averages between each phase-encoding increment decreases the intensity of the ghosts.  相似文献   
32.
Postoperative infections are a dreaded complication in pulmonal surgery. Besides the optimal preparation of the patients and careful operative technique, perioperative antibiotic prophylaxis represents an important factor in avoiding infectious consequences. Owing particularly to the high proportion of patients with malignant, consumptious illnesses in thorax surgery, immune deficiencies must be reckoned with in this group of patients. The spectrum of germs to be expected within the framework of pulmonal surgery determines to some extent which antibiotic shall be used. We have investigated the efficacy of a standardized antibiotic prophylaxis using cefotaxime (Claforan) in 200 pulmonal patients. Pleural empyema is a rare, but nonetheless important infectious illness, as a consequence of pulmonal operations, or also following pneumonia. Whilst the early stages of an empyema can often be successfully treated using only drainage treatment, chronic empyema usually requires a thoracotomy with empyema dissection and excortication, as well as subsequent irrigation-suction drainage treatment. In spite of specific surgical sanitation and irrigation-suction drainage treatment, therapy is often complicated by persistent germs in the thoracic cavity. Instillation therapy with taurolidine can lead to faster healing of the infection in such cases. Purulent mediastinitis is an extremely rare illness, but dreaded owing to its high mortality. The causes of the illness lie in injuries of the trachea, of the bronchial tubes, and of the oesophagus. With the introduction of medial sternotomy as operative entry, mediastinitis as a postoperative complication has increased noticeably in frequency. Mediastinitis occurs as a descending infection as a consequence of odontogenic affections. Owing to frequently late diagnosis, infection is usually advanced, so that simple drainage treatment of the mediastinum no longer suffices in many cases. We introduce our concept of treatment using our own patient collective.  相似文献   
33.
Formalin fixed and paraffin embedded samples from 36 squamous cell carcinomas of the larynx and the oral cavity (pT2N0M0, R0) surrounded by non-tumorous mucosa were studied immunohistochemically using a panel of four different anti-p53 antibodies (CM1, PAbl801, D07, PAb240), a monoclonal anti-mdm2 antibody and MIB1, following wet autoclave antigen retrieval. P53 immunoreactivity was detected in 11/14 laryngeal and in 9/22 oral carcinomas. All p53 positive oral, and all but one laryngeal tumors revealed mdm2 positivity as well, whereas in p53 negative tumors 4/12 and 1/3 mdm2 immunopositive cases were demonstrated, respectively. MIB1 labeling indices of the tumors ranged between 18% – 64% in p53 positive cases, and 10% – 53% in p53 negative ones. The difference was not statistically significant. Close spatial coexpression of p53, mdm2 and MIB1 immunoreactivity was observed at the invasive front of the carcinomas and in the basal and suprabasal layers of the non-tumorous epithelium in all p53 positive cases. However, the MIB1 expression was similarly increased at the invasive margins in carcinomas lacking immunohistochemically detectable p53 alterations. Our results strongly suggest that p53 overexpression does not necessarily correspond to increased rate of proliferation, but rather to mdm2 overexpression and is largely dependent on the anatomical site in case of small and localized squamous cell carcinomas of the head and neck region.  相似文献   
34.
Single photon emission computed tomography (SPECT) with thallium-201-chloride (201TI) was used in 22 patients to assess the grade of malignancy of brain tumors.Low- and high-grade malignant gliomas could be well differentiated by calculating the Grade Index (GI), i.e., 201TI uptake in the tumor area relative to a contralateral brain region. Low-grade gliomas (WHO-grade I–II) usually showed a GI of <1.5. Tumors classified histologically as high-grade malignant (WHO-grade III–IV) had GI values greater than 1.42 and a mean value of 1.89.Until labelled amino-acid tracers for gamma-cameras become commercially available, thallium-201 brain-SPECT can provide an independent and complementary method to CT/MRI for the differential diagnosis of grading of brain tumors. This simple technique can help to reduce sampling errors during needle biopsies of brain tumors, particularly of high-grade lesions incorrectly graded as low-grade tumors due to inadequate biopsy material. In addition, pre- and post-therapy studies can influence the strategy of therapy itself and allow an early detection of recurrences.  相似文献   
35.
Myocardial infarction has great importance for the populations in industrial countries because of the high morbidity and mortality rates. For research of the epidemiological trends in the 1970s and especially in the 1980s, the World Health Organization (WHO) began registering myocardial infarction throughout the world. The most important aspect was the WHO Monitoring of Trends and Determinants of Cardiovascular Diseases (MONICA) project. From 1974 to 1994 and in 1999 in Chemnitz, Germany, data from patients with acute myocardial infarction were collected for the myocardial infarction register. Despite changes in the event rates from year to year, no decrease in the number of myocardial infarctions in the German population aged 25–64 years was detected, contrary to the trend in the Western industrial states in the period from 1984 to 1994. The event rates in men were significantly higher than in women. In 1999, a significant decrease in the event rates in men and women was found. This may be explained by an incomplete registration of patients with myocardial infarction in 1999 because of the change in the structure of the Public Health System. The highest 28-day fatality rates in men were detected in 1989 and 1990. In women with classic myocardial infarction, a decrease in the 28-day fatality rates after 1993 was recorded, reaching lower rates than those of men. Despite methodological problems, the myocardial infarction register can contribute to a comparison of the morbidity, mortality and case fatality rates of myocardial infarction for a longer period.  相似文献   
36.
Attachment Q-Sort (AQS) is a tool for quantifying observations about toddler/caregiver relationships. Previous studies have applied factor analysis to the full 90 AQS item set to explore the structure underlying them. Here we explore that structure by applying multidimensional scaling (MDS) to judgements of inter-item similarity. AQS items are arranged in the MDS solution along three easily interpretable axes: a model that is compatible with but more parsimonious than factor analysis solutions. This geometrical approach suggests ways to modify the AQS—primarily a research tool—to make it more practical for clinical applications. Sets of AQS data are represented and interpreted in the three-dimensional model as vectors. Summaries at a finer-grained level are obtained by finding points in the model where variability across datasets is greatest. We report re-analyses of archival (published) data, and also data collected with streamlined procedures more suitable in the field. Although not reported here, collection and analysis can both be performed online via a website. The general methodology is not restricted to the current application of toddler attachment.  相似文献   
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38.
OBJECTIVE: To estimate the clinical efficacy of topical sinecatechins, a defined green tea extract, in the treatment of external genital and perianal warts. METHODS: This was a randomized, double-blind, vehicle-controlled trial involving 502 male and female patients aged 18 years and older, with 2-30 anogenital warts ranging from 12 to 600 mm(2) total wart area. Patients applied sinecatechins ointment 15% or 10% or vehicle (placebo) three times daily for a maximum of 16 weeks or until complete clearance of all warts, followed by a 12-week treatment-free follow-up to assess recurrence. RESULTS: Complete clearance of all baseline and newly occurring warts was obtained in 57.2% and 56.3% of patients treated with sinecatechins ointment 15% and 10%, respectively, compared with 33.7% for vehicle (both P<.001). Significance was observed at weeks 4 and 6 and all subsequent visits. Numbers needed to treat were 4.3 and 4.4. Partial clearance rates of at least 50% were reported for 78.4% and 74.0% of patients in the sinecatechins ointment 15% and 10% groups compared with 51.5% of vehicle patients. During follow-up, recurrence of any wart was observed in 6.5%, 8.3%, and 8.8% in the sinecatechins ointment 15% group, sinecatechins ointment 10% group, and vehicle patients, respectively. A total of 3.7%, 8.3%, and 0.0% developed new warts, respectively. A total of 87.7% and 87.3% of patients in the sinecatechins ointment 15% and 10% groups, and 72.1% of vehicle patients experienced application site reactions; 49.2%, 46.2%, and 65.4% of those, respectively, were mild or moderate. CONCLUSION: Topical sinecatechins ointments 15% and 10% are effective and well-tolerated in the treatment of anogenital warts. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, www.clinicaltrials.gov, NCT00449982. LEVEL OF EVIDENCE: I.  相似文献   
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40.
Journal of Molecular Medicine - Bei 36 Hunge kranken wurde nach Ausschwemmung der Ödeme der Blutzuckerspiegel nach einer subcutanen Adrenalininjektion untersucht. Die Art des Zuckeranstieges...  相似文献   
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