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排序方式: 共有1386条查询结果,搜索用时 15 毫秒
1.
Liver hemangioma: US-guided 18-gauge core-needle biopsy 总被引:6,自引:0,他引:6
2.
BACKGROUND: There are obvious advantages to increasing donor retention. However, for reasons of blood safety, certain donors may, in fact, be more desirable to retain than others. “Safe” donors are defined as those who provided a blood donation that was negative on all laboratory screening tests and who subsequently reported no behavioral risks in response to an anonymous survey. This study identifies the most important factors affecting the intention of “safe” donors to provide another donation. STUDY DESIGN AND METHODS: An anonymous survey asking about donation history, sexual history, injecting drug use, and recent donation experience was mailed to 50,162 randomly selected allogeneic donors (including directed donors) who gave blood from April through July or from October through December 1993 at one of the five United States blood centers participating in the Retrovirus Epidemiology Donor Study. Before mailing, questionnaires were coded to designate donors with nonreactive laboratory screening tests at their most recent donation. RESULTS: A total of 34,726 donors (69%) responded, with substantially higher response among repeat donors. According to reported intentions only, the vast majority of “safe” donors indicated a high likelihood of donating again within the next 12 months. Only 3.4 percent reported a low likelihood of donating again. A comparison of those likely to return and those unlikely to return reveals significant differences in demographics and in ratings of the donation experience. A higher proportion of those unlikely to return were first-time donors, minority-group donors, and donors with less education. The highest projected loss among “safe” donors was seen for those who gave a fair to poor assessment of their treatment by blood center staff or of their physical well-being during or after donating. CONCLUSION: These data suggest that efforts to improve donors' perceptions of their donation experience, as well as attention to the physical effects of blood donation, may aid in the retention of both repeat and first-time donors. 相似文献
3.
A subgroup of patients with chronic pancreatitis overexpress the c-erb B-2 protooncogene. 总被引:1,自引:0,他引:1
H Friess Y Yamanaka M Büchler K Hammer M S Kobrin H G Beger M Korc 《Annals of surgery》1994,220(2):183-192
OBJECTIVE: Chronic pancreatitis (CP) is a chronic condition associated with pancreatic fibrosis. A small subgroup of patients with CP develop enlargement of the head of the pancreas (EHP). This study examined some of the mechanisms that may lead to the development of EHP. SUMMARY BACKGROUND: The c-erb B-2 protooncogene encodes a 185-kDa transmembrane growth factor receptor (p185) that regulates cell growth and differentiation. METHODS: The authors analyzed c-erb B-2 expression in samples obtained from the head of the pancreas from 26 patients with CP (5 women, 21 men) using immunohistochemical and molecular technique. A diagnosis of CP with EHP was made when the vertical pancreatic head diameter was greater than 4 cm (14 patients), as determined by contrast-enhanced computed axial tomography scan. Pancreatic tissues from 15 healthy organ donors served as control subjects. RESULTS: In all patients without EHP and in the healthy control subjects, p185 immunoreactivity was present at low levels. In contrast, strong p185 immunoreactivity was observed in acinar and ductal cells in all patients with EHP. By in situ hybridization, c-erb B-2 messenger ribonucleic acid (mRNA) grains were expressed at high levels in patients with CP with EHP in both ductal and acinar cells. Northern blot analysis demonstrated a 4.5-fold increase (p < 0.001) in c-erb B-2 mRNA levels in patients with EHP compared with patients without EHP and healthy control subjects. Southern blot analysis did not reveal c-erb B-2 gene amplification or rearrangement. CONCLUSIONS: These findings indicate the c-erb B-2 is not overexpressed in most patients with CP. However, its overexpression in patients with CP with EHP suggest that c-erb B-2 may contribute to the pathophysiologic processes that lead to pancreatic head enlargement. 相似文献
4.
P. O. Berberat H. Ingold A. Gulbinas J. Kleeff M. W. Müller C. Gutt M. Weigand H. Friess M. W. Büchler 《Journal of gastrointestinal surgery》2007,11(7):880-887
Concepts in “fast-track” surgery, which provide optimal perioperative care, have been proven to significantly reduce complication
rates and decrease hospital stay. This study explores whether fast-track concepts can also be safely applied and improve the
outcomes of major pancreatic resections. Perioperative data from 255 consecutive patients, who underwent pancreatic resection
by means of fast-track surgery in a high-volume medical center, were analyzed using univariate and multivariate models. Of
the 255 patients, 180 received a pancreatic head resection and 51 received distal, 15 received total, and 9 received segmental
pancreatectomies. The patients were discharged on median day 10 with a 30-day readmission rate of 3.5%. The in-hospital mortality
was 2%, whereas medical and surgical morbidities were 17 and 25%, respectively. Fast-track parameters, such as first stools,
normal food, complete mobilization, and return to normal ward, correlated significantly with early discharge (p < 0.05). Patients’ age, operation time, and early extubation proved to be independent factors of early discharge, shown through
multivariate analysis (odds ratio: 4.0, 2.0, and 2.8, respectively; p < 0.05). Low readmission, mortality, and morbidity rates demonstrate that fast-track surgery is in fact feasible and safe
and promotes earlier discharge without compromising patient outcomes. 相似文献
5.
Steenbergen EJ; Verhagen OJ; van Leeuwen EF; van den Berg H; von dem Borne AE; van der Schoot CE 《Blood》1995,86(2):692-702
Crosslineage T-cell receptor delta (TCR delta) rearrangements are widely used as tumor markers for the follow up of minimal residual disease in childhood B-precursor acute lymphoblastic leukemia (ALL) by polymerase chain reaction (PCR). The major drawback of this approach is the risk of false-negative results due to clonal evolution. We investigated the stability of V delta 2D delta 3 rearrangements in a group of 56 childhood B-precursor ALL patients by PCR and Southern blot analysis. At the PCR level, V delta 2D delta 3-to-J alpha rearranged subclones (one pathway for secondary TCR delta recombination) were demonstrated in 85.2% of V delta 2D delta 3-positive patients tested, which showed that small subclones are present in the large majority of patients despite apparently monoclonal TCR delta Southern blot patterns. Sequence analysis of V delta 2D delta 3J alpha rearrangements showed a biased J alpha gene usage, with HAPO5 and J alpha F in 26 of 32 and 6 of 32 clones, respectively. Comparison of V delta 2D delta 3 rearrangement status between diagnosis and first relapse showed differences in seven of eight patients studied. In contrast, from first relapse onward, no clonal changes were observed in six patients studied. To investigate the occurrence of crosslineage TCR delta rearrangements in normal B and T cells, fluorescence-activated cell sorter-sorted peripheral blood CD19+/CD3- and CD19-/CD3+ cell populations from three healthy donors were analyzed. V delta 2D delta 3 rearrangements were detected at low frequencies in both B and T cells, which suggests that V delta 2-to-D delta 3 joining also occurs during normal B-cell differentiation. A model for crosslineage TCR delta rearrangements in B-precursor ALL is deduced that explains the observed clonal changes between diagnosis and relapse and is compatible with multistep leukemogenesis of B-precursor ALL. 相似文献
6.
AE Castellano G Micieli P Bellantonio MG Buzzi S Marcheselli F Pompeo F Rossi G Nappi 《Cephalalgia : an international journal of headache》1998,18(9):622-630
Intracerebral vascular reactivity induced by the nitric oxide (NO) donor isosorbide dinitrate (IDN, 5 mg sublingually) is more major and longer-lasting in migraine patients who develop delayed headache in response to the drug. The headache is purportedly due to neuronally-mediated vascular mechanisms. Indomethacin inhibits prostaglandin synthesis, which is involved in NO generation. Indomethacin also decreases cerebral blood flow by constricting precapillary resistance vessels. In the present study, the hemodynamic effects of indomethacin were evaluated in migraine patients and healthy controls by means of transcranial Doppler monitoring. Indomethacin caused a significant decrease in mean flow velocity in the middle cerebral artery. This was an additional effect to the mean velocity decrease induced by IDN. The interactions between the two drugs suggest that their effects on cerebral hemodynamics (and pain) may be of relevance both in understanding the role of NO in migraine pathogenesis and in evaluating symptomatic treatments for migraine attacks. 相似文献
7.
8.
Hans Brunner Thomas C Wetter Birgit Hogl Alexander Yassouridis Claudia Trenkwalder Elisabeth Friess 《Movement disorders》2002,17(5):928-933
We investigated non-rapid eye movement (non-REM) sleep in patients with newly diagnosed Parkinson's disease (PD) who had never previously received dopaminergic medication. There were no significant differences in the conventional sleep parameters between de novo patients with PD and a healthy control group, but the length of stage 1 sleep and the number of awakenings increased significantly upon administration of dopaminergic drugs. Analyzing the quantitative electroencephalogram (EEG), we observed a significant reduction in the low-delta frequency range and a nonsignificant increase in the sigma frequency range in de novo patients with PD. The dopaminergic medication also nonsignificantly reduced the low-delta and sigma frequencies, the latter to the level of the controls. Possible mechanisms that may account for the observed differences are discussed. It is suggested that Parkinson's disease as well as the application of dopaminergic drugs exerts a desynchronizing effect on the sleep EEG that is reflected in a disruption of sleep continuity. 相似文献
9.
J.P. Neoptolemos M. G.T. Raraty P. Ghaneh H. Hickey D.D. Stocken J. A. Dunn H. Friess M.W. Büchler 《Der Chirurg》2003,74(3):191-201
Recent advances have been made in the treatment of pancreas cancer. Specialized pancreas centres have reported an increasing rate of resections with reduced postoperative mortality. On account of the highly aggressive nature of pancreas cancer, there is a great challenge in identifying effective therapy concepts for advanced stages of the cancer as well as for the development of resection-associated measures. As large-scale, randomised, controlled studies are lacking, the additive therapy concepts after resection do not have a sufficiently scientific basis. The ESPAC-1 study, which included 600 patients, surpassed all previous studies on adjuvant therapy for pancreas cancer. This study has shown,for example, that the most promising adjuvant chemotherapy with 5-fluorouracil and folic acid leads to an equal if not better result than the multimodal regimen. This regimen can be superseded with the use of Gemcitabine, which will be evaluated in the ESPAC-3 study that includes 990 patients from various European countries including Germany, as well as from Canada and Australia. Participation in the large, phase-3 study therefore plays a key role in the continued development of the management of pancreas cancer. 相似文献
10.
P物质及其受体在慢性胰腺炎组织的表达和临床意义 总被引:3,自引:1,他引:2
目的 了解P物质及其受体NK-1R在正常胰腺和慢性胰腺炎中的表达,探讨它们与慢性胰腺炎时疼痛发生的关系。方法 25个慢性胰腺炎标本取自慢性胰腺炎手术,男性18例,女性7例,正常胰腺组织取自20个器官捐献者,男性11例,女性9例。应用实时定量逆转录整合酶链反应(RT-PCR)技术,检测正常胰腺和慢性胰腺炎组织中P物质和NK-1R的mRNA水平,应用Western blot技术检测NK-1R的蛋白水平,应用免疫组织化学方法进行NK-1R的组织学定位。将P物质及其受体NK-1R mRNA水平与疼痛的程度,发作频率和病程进行分析,寻找其中的相关性。结果 与正常胰腺相比,慢性胰腺炎组织中P物质和NK-1R mRNA和蛋白都过度表达,NK-1RmRNA水平与疼痛的程度,发作频率和病程明显相关。免疫组化检查显示,NK-1R的表达主要位于胰腺腺泡,胰腺导管,神经纤维和炎性细胞。结论 慢性胰腺炎组织中P物质和NK-1R的表达水平都明显上调,扰乱了神经激肽的作用环节,NK-1R的过度表达与疼痛发生有关。 相似文献