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1.
Choleragenoid (cholera toxin B-fragment; CTB) is an anterograde, retrograde and transganglionic neuronal tracer. We describe a method for detecting CTB-labeled neuronal cell bodies, neurites and boutons at the ultrastructural level, using postembedding immunogold techniques on freeze-substituted Lowicryl HM20™ embedded nervous tissue. Primary afferents and motoneurons were labeled by injection of CTB in the dorsal ramus of the C2 spinal nerve of the rat. Following fixation with paraformaldehyde (4%) and glutaraldehyde (0.25%), tissue sections from the spinal cord C2 segment were freeze-substituted and embedded in Lowicryl HM20™ and subsequently processed with postembedding immunocytochemistry for CTB and glutamate. Immunogold particles indicating CTB immunoreactivity were found over primary afferents and motoneurons. In primary afferents in the central cervical nucleus (CCN) and motor nuclei, immunogold labeling was seen in boutons over vesicle-containing axoplasm and to a lesser extent over axoplasm devoid of vesicles, but not over mitochondria or axolemma. In motoneurons, immunogold particles were seen over the Golgi apparatus in the soma and over lysosomes in both soma and dendrites. Quantification of glutamate-like immunoreactivity in 20 CTB-labeled and 20 CTB-negative boutons in the neuropil was found similar, indicating that CTB does not interfere with the immunocytochemical detection of neuronal epitopes such as the transmitter substance glutamate.  相似文献   
2.
Summary. In recent years the continuity equation has been established as a valuable non-invasive method for calculating aortic valve area. The continuity equation cannot be used if there is calcification or sub-valvular stenosis in the left ventricle-outflow tract, because the area of the outflow trace is not circular in those cases. The authors have tested the value of a non-invasive variant of the Gorlin formula, as an alternative method of identifying severe aortic stenosis. They examined 32 consecutive patients with aortic stenosis with both methods. Seventeen patients had severe stenosis (valve area^0–7 cm2), calculated by the continuity equation. The other 15 patients had moderate stenosis (valve area 0–7–1–0 cm2). Using the non-invasive variant of the Gorlin formula, the authors were able to identify 16 of the 17 cases with severe stenosis, thus showing that the method is useful for identifying severe aortic stenosis. (P<0–001 by x2-test).  相似文献   
3.
Reference data files support the evaluation of myocardial perfusion single-photon emission tomography (SPET). The aim of this study was to create a large reference data base for technetium-99m sestamibi SPET, age and gender matched to the general patient population. One hundred and twenty-eight healthy volunteers (76 males and 52 females) with a likelihood of coronary artery disease of less than 5% underwent rest and maximal exercise99mTc-sestamibi SPET with a 2-day protocol and 180° elliptical rotation. The normalized activity values of99mTc-sestamibi in the inferior wall differed significantly between men and women. Age variations were found for men in the anterior wall. Normalized activity values in all four walls were strikingly similar during rest and stress. Our results suggest that the use of reference files in99mTc-sestamibi SPET requires a gender- and, for males, possibly an age-matched reference population. Different reference files at rest and during stress might not be necessary.  相似文献   
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The internal-standard method and the powder diffractometer have been applied here to the quantitative determination of urinary stone constituents by x-ray diffraction (XRD). Reference intensity ratios determined for six stone substances were used in the reduction of intensity data. Constituent concentrations calculated for 21 stones were compared with values obtained from an element-sensitive technique. We conclude that XRD analysis alone cannot be regarded as a routine technique for the quantitative characterization of uroliths, but that semiquantitative XRD analysis supplemented by accurate quantitative elemental data is more suitable for the precise determination of true stone composition.  相似文献   
6.
BACKGROUND: Hymenoptera venom immunotherapy in allergic patients is a well-established treatment modality for the prevention of systemic anaphylactic reactions caused by insect stings. A variety of therapy regimens exists, from conventional to rush and ultrarush modalities that operate on continuous or intermittent schedules. OBJECTIVE: The aim of this study was to report the 8-year experience with our rush venom immunotherapy regimen in predominantly high-risk patients and to compare data on safety and convenience with the results of 26 studies published from 1978 to 2001. METHODS: One hundred one patients allergic to bee, yellow jacket, or hornet venom were treated with rush Hymenoptera venom immunotherapy. Diagnosis and selection of patients for venom immunotherapy were carried out according to the recommendations of the European Academy of Allergology and Clinical Immunology. We used a 4-day regimen, and the incidence and nature of systemic reactions (SRs) were documented. Fifty-two patients were treated with honeybee venom, and 49 were treated with yellow jacket venom. RESULTS: One hundred (99%) patients reached the maintenance dose. We observed 8 injection-related SRs (0.47% of all injections given) in 7 (6.9%) patients. The number of SRs was higher in patients treated with bee venom extract (12%) compared with in patients receiving yellow jacket venom extract (2%). There was no significant difference in the risk of SRs between female and male patients. The incidence of SRs was considerably lower than the average of 17.8% reported in the literature. CONCLUSION: With a rush immunotherapy regimen over a time period of 8 years in predominantly high-risk patients, the incidence of SRs was low, despite the high number of patients with bee venom allergy, who are more likely to have side effects. Epinephrine as rescue medication was never necessary, and the regimen proved to be safe and convenient for both the patients and the medical staff.  相似文献   
7.
Summary Although cryostat sections in general allow a distinction to be made between malignant melanomas and other pigmented lesions in clinically doubtful cases, the differential diagnosis may be difficult. The histological and cytological criteria taken into account can be classified as major, minor, and insufficient. Knowing the diagnostic value of each makes a conventionally established diagnosis safer. Variance analysis does not contribute to the problem but it can nevertheless be shown that the evaluation of six major criteria makes a quick and reliable cryostat section diagnosis possible. If these results are confirmed in a prospective study it would be a decisive step on the way to a quicker and safer cryostat section diagnosis of malignant melanoma, even for the less experienced histopathologist.The results published here were presented in part at the DDG meeting 1980 at Westerland/SyltWe are grateful to Miss Schubert, Institute of Biomathematics of the University of Munich, for the statistical evaluations  相似文献   
8.
Caspersson's method of labelling chromosomes with DNA-binding fluorescent agents has been applied to the study of human chromosomes. Fluorescence distribution curves of normal metaphase chromosomes treated with quinacrine mustard (QM) were obtained by scanning transparent pictures of the labelled chromosomes in a Beckman Analytrol® an instrument normally used for scanning electrophoresis strips. Representative fluorescence distribution curves of the different chromosomes, as well as one complete "QM karyotype", have been presented. The distribution curves of individual chromosomes appear to be characteristic and reproducible and it was concluded that the technique of fluorescent labelling holds great promise for identification of individual human chromosomes end chromosomal regions.  相似文献   
9.
PURPOSE: Investigation of high-dose chemotherapy (HD-CT) followed by autologous hematopoietic stem-cell support compared with standard-dose chemotherapy (SD-CT) as adjuvant treatment in patients with primary breast cancer and 10 or more positive axillary lymph nodes. PATIENTS AND METHODS: Between November 1993 and September 2000, 307 patients were randomized to receive (following four cycles of epirubicin 90 mg/m(2) and cyclophosphamide 600 mg/m(2), intravenously every 21 days) either HD-CT of cyclophosphamide 1500 mg/m(2), thiotepa 150 mg/m(2), and mitoxantrone 10 mg/m(2), intravenously for 4 consecutive days followed by stem-cell support; or SD-CT in three cycles of cyclophosphamide 500 mg/m(2), methotrexate 40 mg/m(2), and fluorouracil 600 mg/m(2) intravenously on days 1 and 8, every 28 days. The primary end point was event-free survival. RESULTS: After a median follow-up of 3.8 years, 144 events with respect to event-free survival have been observed (HD-CT: 63 events; SD-CT: 81 events). The first event of failure (HD-CT v SD-CT) was an isolated locoregional recurrence (nine v 11), a distant failure (52 v 68), and death without recurrence (two v two). The estimated relative risk of HD-CT versus SD-CT was 0.75 (95% CI, 0.54 to 1.06; P =.095). Overall survival showed no difference (HD-CT: 40 deaths; SD-CT: 49 deaths). CONCLUSION: There was a trend in favor of HD-CT with respect to event-free survival, but without statistical significance. Further follow-up and a meta-analysis of all randomized studies will reveal the effect of HD-CT as compared with SD-CT as adjuvant treatment in high-risk primary breast cancer.  相似文献   
10.
The objective of this study was to investigate social hearing in successful users of multichannel cochlear implants (CIs) and to compare the scores with those of a group of hearing-impaired adults using acoustical hearing aids (HAs). Out of 88 patients who had undergone surgery, 75 CI users with a mean age of 55 years and a mean pre-operative hearing level of 113dB in the better ear were compared with 59 users of acoustical HAs with a mean age of 56 years and a mean hearing level of 82dB in the better ear. Seven CI patients were non-users and were excluded from the study. The Performance Inventory for Profound and Severe Loss, a questionnaire that measures different aspects of hearing handicap, was used. The CI group scored significantly better than the HA group in three of six evaluated categories, measuring subjective intensity of sounds, speech with visual cues, and response to auditory failure. Awareness of environmental sounds, speech with no visual cues and personal reactions did not differ significantly. The group of successful CI users scored higher on a self-report measure than did a group of users of acoustical HAs with moderate- severe-profound deafness. The best CI users scored better than the best HA users, and the worst CI users scored worse than the worst HA users.  相似文献   
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