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61.
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Thromboendarterectomy is performed to treat chronic thromboembolic pulmonary hypertension with obstruction of main, lobar, or segmental pulmonary arteries. The present study evaluated surgical specimens removed between 1990 and 2001. Medical histories and microscopic slides were reviewed in each case. Study slides were stained with hematoxylin and eosin and Verhoeff-van Gieson and evaluated for thrombus, collagen, elastin, atherosclerosis, hemosiderin, calcification, and inflammation. The study group comprised 54 patients (30 women and 24 men), ranging in age from 33 to 77 years (mean, 58 years). Clinically, 28 (52%) had a history of deep leg vein thrombosis and 42 (78%) had a history of pulmonary embolism; 24 (44%) had both events. Coagulation abnormalities were documented in 15 (28%); autoimmune or hematologic disorders, in 8 (15%). Pulmonary thromboendarterectomy was bilateral in 52 patients (96%) and right-sided in 2. Six patients also had obstructions resected from the main pulmonary arteries. Obstruction limited to segmental arteries occurred only in women. Grossly, right-sided specimens were larger than left-sided ones (P = 0.003). Microscopically, ages of thrombi were uniform in 72% and variable in 28%. Intima was thickened in all patients and consisted of collagen (100%), elastin (67%), hemosiderin (56%), inflammation (53%), atherosclerosis (32%), and calcification (15%). We determined that pulmonary thromboendarterectomy was performed most often in middle-aged and elderly patients with a history of deep venous thrombosis or pulmonary embolism. Less than 50% of the patients had an identifiable coagulation, autoimmune, or hematologic abnormality. Most patients had bilateral disease and resections. Right-sided specimens were significantly larger than left-sided specimens, and lower lobe involvement was more common than involvement elsewhere. Resected tissues most commonly exhibited old organized thrombus.  相似文献   
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64.
The performance of two DNA line probe assays, a new version of INNO-LiPA Mycobacteria (Innogenetics, Ghent, Belgium) and the GenoType Mycobacterium (Hain Diagnostika, Nehren, Germany), were evaluated for identification of mycobacterial species isolated from liquid cultures. Both tests are based on a PCR technique and designed for simultaneous identification of different mycobacterial species by reverse hybridization and line probe technology. The INNO-LiPA Mycobacteria v2 targeting the 16S-23S rRNA gene spacer region was developed for the simultaneous identification of 16 different mycobacterial species. The GenoType Mycobacterium, which targets the 23S rRNA gene, allows simultaneous identification of 13 mycobacterial species. Both tests were evaluated on 110 mycobacterial strains belonging to 22 different mycobacterial species (20 reference strains, 83 clinical strains, and 4 Mycobacterium kansasii strains isolated from tap water) that were previously inoculated into MB/BacT bottles. The sensitivity of both methods, defined as the number of positive results obtained with the Mycobacterium genus probe together with an interpretable result on the number of samples tested was 110 of 110 (100%) for INNO-LiPA and 102 of 110 (92.7%) for GenoType. For samples with interpretable results, INNO-LiPA was able to correctly identify 109 of 110 samples (99.1%), whereas the GenoType correctly identified 100 of 102 samples (98.0%). Both tests were easy to perform, rapid, and reliable when applied to mycobacterial identification directly from MB/BacT bottles.  相似文献   
65.
The distribution of putative receptors for the peptide galanin was studied in the normal post-mortem human brain by using 125I-galanin (0.5 nM) in combination with in vitro receptor autoradiography. Specific binding of 125I-galanin was found in a large number of brain areas throughout the neuraxis. Highest binding densities occurred in the basal forebrain and hypothalamus, while the basal ganglia, major parts of the thalamus and the tectum were found to be poor in binding sites. All cortical areas harboured 125I-galanin binding, and in the visual cortex a laminated pattern was present. In the hippocampus, 125I-galanin binding occurred in layer 2 of the entorhinal cortex, in the uncus and in the hippocampal-amygdala area. In the brain-stem, 125I-galanin binding was found in serotoninergic and noradrenergic cellgroups as well as in the reticular formation and in the parabrachial nuclei. Galanin receptors may, thus, mediate the response of galanin in numerous structures in the human brain.  相似文献   
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BACKGROUND: The range of nucleic acid-based technologies for the molecular detection of pathogens has grown rapidly in recent years. The influx of new testing methods into the clinical laboratory, demands for evaluation and standardisation of methods, interpretation of results and evaluation of laboratory performance have highlighted the need for internal and External Quality Assessment (EQA) systems more than ever before. External Quality Assessment panels demand reproducible, stable specimens of consistent form, suitable for transportation. OBJECTIVES: To determine the stability of freeze-dried viral specimens in terms of molecular detection. STUDY DESIGN: When EQA specimens are prepared, they undergo long-term storage and testing as part of the quality control (QC) process. The frequency and nature of testing is dependent on the resources and methodologies available at the time. A range of virus preparations used for EQA was monitored over a period of months to years in a retrospective study; the available quality monitoring data for the five viruses, including storage temperature and method of detection were analysed. RESULTS: The nucleic acid (DNA or RNA) of the freeze-dried viruses included in the study was readily detectable over a long period of time. Quantitative analysis indicated that detectable concentrations of nucleic acid post-freeze drying were similarly maintained. Storage temperature was an important factor in the stability of HCV, but other viruses were unaffected by storage at different temperatures. CONCLUSIONS: In summary, the molecular detection of nucleic acid (DNA or RNA) in freeze-dried specimens of HSV1, HSV2, HBV, HCV and HIV is possible even after prolonged storage, in some cases at a range of temperatures. Freeze drying allows large-scale production of viral specimens of high quality for EQA, which are stable in varying storage and shipment conditions. Furthermore, detection of each virus was possible with a range of commonly used molecular diagnostic methods.  相似文献   
68.
Children with genetic diseases must be followed for long periods of time to seek new findings. Other patients require further check-ups and studies to be diagnosed. Some patients never return for medical care after the first consultation, which may have serious consequences. We reviewed 400 medical charts of patients with genetic disease to analyze overall attendance to the genetics clinic, investigate some of the causes of failure to seek medical advice, and determine the differences between those first seen as outpatients or as inpatients. The mean follow-up period was 8.3 months (range 0-79), and the average number of visits was 2.8 (range 1-16). Forty eight percent of the cases first seen as inpatients were evaluated only once and 14% twice; while 22 and 21% of the 300 cases first seen as outpatients attended once and twice, respectively (P = 0.0). Appointment keeping was apparently not affected by the presence or absence of diagnosis. Overall, 97 patients were discharged, 7 died, 55 continued on follow-up, 62 attended other hospital services-but not genetics-and 179 were completely lost to follow-up. Diagnosed patients were counseled more frequently than undiagnosed patients (62 vs. 5%); and 71% of the diagnosed patients first seen as outpatients but only 36% of undiagnosed cases first seen as inpatients were counseled, differences between these two groups were significant (P = 0.005). We conclude that keeping the patient with genetic disease on follow-up is a difficult task. New educational strategies must be planned to improve this worrisome situation.  相似文献   
69.
BACKGROUND: Cupressaceae is a family of plants resistant to airborne contamination, and its pollen is the main cause of winter allergic respiratory diseases, especially in North America, Japan, and Mediterranean countries. Recently, a major allergen from Cupressus arizonica pollen grains, Cup a 3, was cloned and expressed. OBJECTIVE: To study the effects of air pollution on the expression of Cup a 3, a thaumatinlike protein, in C. arizonica pollen grains using a combination of transmission electron microscopy and immunocytochemical techniques. METHODS: Observations were made in mature and hydrated C. arizonica pollen grains from various regions in Spain with different degrees of air pollution. Specimens were fixed using freezing protocols, and ultrathin sections were incubated with anti-rCup a 3 rabbit polyclonal antibodies. RESULTS: Labeling of Cup a 3 was detected in mature and hydrated C. arizonica pollen grains. It was more intense in pollen from polluted air regions, and abundant gold particles were observed as they were released through the pollen grain walls. Furthermore, gold particles remained abundant in the pollen cytoplasm. The labeling was noticeably lower in pollen grains from unpolluted air regions. CONCLUSIONS: Cup a 3 is present in the cytoplasm and walls of cypress pollen grains during the air dispersion and hydration stages. The abundance of Cup a 3 in pollen grains under polluted air conditions indicates that these cypresses intensify their activity as a defense from environmental pollution, thus strengthening their allergenicity.  相似文献   
70.
A 53-yr-old woman presented with a left upper quadrant abdominal mass attached to the body of the pancreas. Fine-needle aspiration (FNA) yielded cyst fluid containing numerous benign, mature squamous cells, keratin debris, and inflammatory cells. The diagnosis of dermoid cyst was subsequently rendered on the resected specimen. The cytologic and histologic features are presented. FNA cytology proves to be a valuable diagnostic adjunct in the preoperative evaluation of a patient with dermoid cyst of the pancreas.  相似文献   
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