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121.
OBJECTIVE: Organ donation is a complex decision for family members of Asian donors. The impact of cadaveric organ donation on both Chinese and Western donor families has not been well investigated within a cultural framework. The purposes of this study were to follow Chinese family members' appraisal of their decision to donate organs, to explore the possible negative and positive impacts of organ donation on their family life, and to determine what help they expected from healthcare providers during the first 6 months after donation. METHODS: Twenty-two family members (10 men and 12 women) of cadaveric organ donors who signed consent forms at an organ transplant medical center in Taiwan participated in this project and completed in-depth interviews during the sixth month after donation. RESULTS: Participants were 25 to 56 years old (mean = 48.15 +/- 8.31 years). The type of kinship of the participants included the donor's parents, older sister, and spouse. Subjects reported several negative impacts: worry about the donor's afterlife (86%), stress due to controversy among family members over the decision to donate (77%), and stress due to others' devaluation of the donation (45%). Positive impacts reported by the subjects included having a sense of reward for helping others (36%), having an increased appreciation of life (32%), having closer family relationships (23%), and planning to shift life goals to the study of medicine (9%). Subjects expected the transplant team to provide information about organ recipients (73%), to submit the necessary documents so that family members could receive healthcare payments from the insurance company (68%), to help resolve legal proceedings and settlements associated with accidents (64%), and to not overly publicize their decision to donate (64%). CONCLUSIONS: Although all of the subjects reported that organ donation was the right decision, the decision to donate did not protect Taiwanese donor families from negative psychocognitive bereavement. The impacts of organ donation were affected by the subject's social cultural, spiritual, and legal context and the nature of their bereavement. 相似文献
122.
The purpose of this study is to analyze the characteristics of dynamic wedges (DW) and to compare DW to physical wedges (PW) in terms of their differences in affecting beam spectra, energy fluence, angular distribution, contaminated electrons, and dose distributions. The EGS4/BEAM Monte Carlo codes were used to simulate the exact geometry of a 6 MV beam and to calculate 3-D dose distributions in phantom. The DW was simulated in accordance with the segmented treatment tables (STT). The percentage depth dose curves and beam profiles for PW, DW, and open fields were measured and used to verify the Monte Carlo simulations. The Monte Carlo results were found to agree within 2% with the measurements performed using film and ionizing chambers in a water phantom. The present EGS4 calculation reveals that the effects of a DW on beam spectral and angular distributions, as well as electron contamination, are much less significant than those for a PW. For the 6 MV photon beam, a 45 degrees PW can result in a 30% increase in mean photon energy due to the effect of beam hardening. It can also introduce a 5% dose reduction in the build-up region due to the reduction of contaminated electrons by the PW. Neither this mean-energy increase nor such dose reduction is found for a DW. Compared to a DW, a PW alters the photon-beam spectrum significantly. The dosimetric differences between a DW and a PW are significant and clearly affect the clinical use of these beams. The data presented may be useful for DW commissioning. 相似文献
123.
Mitochondrial DNA polymorphisms in Yunnan nationalities in China 总被引:4,自引:0,他引:4
Nucleotide sequences of the D-loop region of human mitochondrial DNA from four Yunnan nationalities, Dai, Wa, Lahu, and Tibetan,
were analyzed. Based on a comparison of 563-bp sequences in 99 people, 66 different sequence types were observed. Of these,
64 were unique to their respective populations, whereas only 2 types were shared between the Lahu and Wa nationalities. The
D-loop sequence variation and phylogenetic analysis suggested that the 99 mtDNA lineages were classified into eight clusters
in the phylogenetic tree. All lineages that had a 9-bp deletion in the COII/tRNALys intergenic region appeared in one cluster in the D-loop tree, suggesting a single event of the deletion in the Yunnan nationalities
studied. Genetic distances, based on net nucleotide diversities between populations including Han Chinese and mainland Japanese,
revealed that the Dai, Wa, Lahu, and Han Chinese are closely related to each other, while Tibetan and mainland Japanese formed
a single cluster. The bootstrap probabil-ity of separation between the Dai-Wa-Lahu-Chinese clade and the Tibetan-Japanese
clade was 99%, indicating that there are at least two different origins among minority groups in Yunnan province. Although
the genetic distance between Tibetan and Japanese within the clade is rather long, the results may shed light on the origins
of mainland Japanese.
Received: December 22, 2000 / Accepted: January 18, 2001 相似文献
124.
125.
Cytogenetic analysis by short-term culture of a lipoma from the posterior neck region of a 63-year-old man showed a t(X;12)(q27;q14) as the sole chromosomal abnormality. Rearrangement of band 12q14 is nonrandom in lipomas, although its involvement with a sex chromosome has not been reported earlier. 相似文献
126.
Paraffin-section immunohistochemical analysis was performed using a monoclonal antibody against CD163 to evaluate the antibody's usefulness in identifying cells of monocyte/macrophage lineage in normal and neoplastic conditions. Normal human tissue samples and samples from 211 hematopoietic disorders and 115 nonhematopoietic neoplasms were examined. The distribution of KP1 and PG-M1, monoclonal antibodies to the macrophage-associated CD68 antigen, also were evaluated for comparison. CD163 immunoreactivity was observed in resident macrophages of all normal tissue samples except splenic white pulp macrophages and germinal center tingible body macrophages. Among hematopoietic disorders and nonhematopoietic neoplasms, CD163 expression was restricted largely to cases of chronic myelomonocytic leukemia, histiocytic sarcoma, sinus histiocytosis with massive lymphadenopathy, and littoral cell angioma. Acute myeloid leukemias (AMLs) with monocytic differentiation were CD163- with the exception of 1 case of acute monoblastic leukemia. Most myeloid sarcomas also were CD163-. Compared with the CD68 antibodies, CD163 demonstrated greater specificity as a marker of disorders of monocyte/macrophage origin. However, immunohistochemical evaluation of CD163 expression does not seem to be a sensitive means of determining monocytic differentiation in AMLs in paraffin sections or establishing a diagnosis of myeloid sarcoma. 相似文献
127.
128.
采用墨汁硝酸银水溶液局部动脉灌注方法,研究了胎儿、犬和家兔肾上腺(总计80例)器官内的淋巴管.所见结果表明:胎儿和犬肾上腺被膜内及腺体内的较粗大静脉周围存在淋巴管和毛细淋巴管;家兔肾上腺的淋巴管仅分布于被膜内;在肾上腺皮质和髓质的实质内,无论胎儿、犬和兔,仅有血管并无淋巴管或毛细淋巴管. 相似文献
129.
2,4,4'-Trichlorobiphenyl or PCB congener 28 was given to Sprague-Dawley weanling rats and the experimental diets were prepared by mixing the congener in 4% corn oil. The congener was administered to animals placed in four groups, each comprising 10 males or females. The diets contained 0.05, 0.5, 5, or 50 ppm congener. The fifth or control group comprised animals that received diets mixed with corn oil. Thirteen weeks after commencement of dosing, animals were euthanized and liver specimens were harvested from the animals and prepared for electron microscopy and biochemical analyses. The hepatocyte architectural modifications included an augmentation of SER profiles and an elevation of peroxisome numbers in animals regardless of gender, and mitochondrial abnormalities in the females only. Mitochondrial aberrations consisted of abnormal shapes and cristae in atypical orientation. The alterations were revealed in animals of the 5-and 50-ppm groups and were more extensive in the females. Ethoxyresorufin-O-de-ethylase activity was significantly high in the animals of the 50-ppm group. The results suggest that the female rats were more sensitive than the males to congener 28, and the no observable adverse effect level (NOAEL) was believed to be 0.5 ppm for the congener. 相似文献
130.
John David N. Dionisio Alfonso F. Cárdenas PhD Robert B. Lufkin Antonio DeSalles Keith L. Black Ricky K. Taira Wesley W. Chu 《Journal of digital imaging》1997,10(1):21-26
A prototype multimedia medical database is described for supporting thermal ablation therapy of brain tumors. Its design is motivated by the major need to manage and access multimedia information on the progress and reaction of tumors to various therapy protocols. The database links images to patient data in a way that permits the user to view and query medical information using alphanumeric, temporal, and feature-based predicates. Visualization programs permit the user to view or annotate the query results in various ways. These results support the wide variety of data types and presentation methods required by neuroradiologists to manage thermal ablation therapy data. The database satisfactorily meets the requirements defined by thermal ablation therapy. A similar approach is being undertaken for supporting different therapies of other types of tumors, thus showing the generality of our approach. 相似文献