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31.
Summary In 11 adult cats, lightly anesthetized with chloralose-urethane, blood from both common carotid arteries was led into a plastic chamber of 15–20 ml and returned to the carotids at a point 1.5 cm more cranial. By doing so arterial blood was assumed to pool within the chamber and lose itsP
CO
2 oscillations which are normally known to exist as a result of the respiratory cycle. In control periods blood bypassed the chamber, thus maintaining respiratoryP
CO
2 oscillations. Spontaneous ventilation was measured spirometrically. The animals were breathing pure O2.Results. 1. When the sinus (carotid) nerves were intact or sectioned there was no significant difference in ventilation before or after switching from non-oscillating to oscillatingPa
CO
2. 2. When the vertebral arteries were ligated a drop in ventilation occurred after turning to oscillatingPa
CO
2 which was followed by a slight rise above control values after 30–50 sec. This phenomenon was independent of sinus nerve integrity. Thus in hyperoxie condition the smallPa
CO
2 oscillations known to occur in phase with respiration do not seem to provide a respiratory stimulus to resting ventilation above that generated by the mean level ofPa
CO
2. The ventilatory depression after vertebral artery ligation must at this time remain unexplained. 相似文献
32.
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
33.
Piffkó J Bánkfalvi Á Öfner D Tötsch M Berens A Joos U Böcker W Schmid KW 《Pathology oncology research : POR》1996,2(1-2):37-42
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.
Rüdiger Burkard Klaus Peter Kaiser Helmut Wieler Peter Klawki Axel Linkamp Lutz Mittelbach Thomas Göller 《Neurosurgical review》1992,15(4):265-273
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.
36.
Axel Müller Johannes Schweizer Detlef Quietzsch Rainer Koch Günther Voigt 《Zeitschrift fur Gesundheitswissenschaften》2004,12(2):111-122
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
37.
John Kirkland David Bimler Andrew Drawneek Margaret McKim Axel Sch lmerich 《Early child development and care》2004,174(7):701-719
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
38.
39.
Sinecatechins, a defined green tea extract, in the treatment of external anogenital warts: a randomized controlled trial 总被引:1,自引:0,他引:1
Tatti S Swinehart JM Thielert C Tawfik H Mescheder A Beutner KR 《Obstetrics and gynecology》2008,111(6):1371-1379
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
40.