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排序方式: 共有3930条查询结果,搜索用时 31 毫秒
1.
Akira Sawaki Nobumasa Mizuno Kuniyuki Takahashi Tsuneya Nakamura Masahiro Tajika Hiroki Kawai Toshifumi Isaka Hiroshi Imaoka Yasuyuki Okamoto Masatoshi Aoki Hiroyuki Inoue Ahmed AS Salem Yasushi Yatabe Kenji Yamao 《Digestive endoscopy》2006,18(1):40-44
Background: Gastrointestinal stromal tumors (GIST) are one of the most common mesenchymal tumors of the gastrointestinal tract. GIST are defined by positive immunohistochemical staining for KIT or CD34 and thus are generally diagnosed after surgery. Because small GIST are rarely diagnosed before surgery, the clinical course of these small tumors is not clear. The aim of the present study was to follow changes in size and configuration of small GIST that were pathologically confirmed using endoscopic ultrasonography‐guided fine‐needle aspiration biopsy (EUS‐FNAB). Methods: Between July 1997 and December 2003, 16 tumors in 16 patients (10 men and 6 women) with an immunohistochemical diagnosis of GIST were regularly followed in our hospital. The median patient age when EUS‐FNAB was performed was 62 years (range 26–82 years) and the median follow‐up period was 4.9 years (range 0.5–9.6 years). Results: Fourteen tumors showed no remarkable changes in size and shape during follow up compared with the initial diagnosis. Two tumors enlarged: one tumor approximately doubled its diameter in 8 years and the other tumor increased from 1.8 cm at diagnosis to up to 10 cm after only 2 years. Doubling time of the latter tumor was calculated as 3.1 months. Conclusions: We conclude that EUS‐FNAB might be a good modality for final diagnosis of GIST without surgery, and that GIST without rapid growth on follow up can be endoscopically followed. 相似文献
2.
Liver hemangioma: US-guided 18-gauge core-needle biopsy 总被引:6,自引:0,他引:6
3.
4.
P Salem 《The Medical journal of Malaysia》1991,46(4):376-378
A thirty six week gestation male baby weighing three kilogram was born to a twenty five year old mother by spontaneous vaginal delivery. At four hours of life, the baby developed respiratory distress with cyanosis and was admitted to the neonatal intensive care unit. There was clinical and radiological evidence of bilateral pleural effusion. Thoracentesis revealed a transudate. Repeated thoracentesis was necessary to relieve the respiratory distress. Subsequently, multi resistant Klebsiella aerogenes was isolated from the blood. The baby expired due to gram negative sepsis. 相似文献
5.
Cancer mortality in the elderly has rarely been analyzed. It is most notably characterized by the level of diagnostic accuracy at ages prone to comorbidities. Trend analysis over the last thirty years and disparities in mortality have underscored the increasing cancer mortality in the over-65 age bracket as well as the relevance of local health context in understanding the significant differences seen throughout France. 相似文献
6.
A procedure for the determination of methotrexate in human plasma is reported. The analysis involved extraction of methotrexate as an ion pair in ethyl acetate. Reconstituted residue was analyzed using reverse phase C-18 column and a mobile phase consisting of acetate buffer (87%), methanol (6.5%), and acetonitrile (6.5%). The methotrexate recovery range was 95-97%. Theophylline was used as internal standard with a recovery of 96%. The intraday coefficient of variation for the assay ranged from 1.8-3.0%, while interday variation coefficient range was 3.5-3.7%. The method is selective, reproducible, and covers a wide range of methotrexate concentrations in patient's plasma. 相似文献
7.
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
8.
G Fountzilas D Afthonidis P Geleris N Salem G Kottas C Halkidis P Apostolidis M Beer A Tourkantonis 《Anticancer research》1992,12(1):231-234
Indices of cardiac function were measured in 49 women who received adjuvant treatment for stage II breast cancer. The combination chemotherapy consisted of six monthly courses of cyclophosphamide, 500 mg/m2, mitoxantrone, 10 mg/m2 and fluorouracil, 500 mg/m2 (CNF). Left ventricular function was assessed by echocardiography, systolic time intervals and nuclear angiography. The values of the echocardiographic left ventricular end diastolic diameter (Dd) and end systolic diameter (Ds), and those of the index of preejection period (PEPI) and the ratio of the preejection period to left ventricular ejection time (PEP/LVET), determined in 41 patients before chemotherapy, at midcourse and after chemotherapy by echocardiography and systolic time intervals (STI), showed a slight but significant increase. All these values remained within normal limits. Resting nuclear angiography, performed before and after treatment, showed a decrease in LVEF by 10% or more in four patients; the postchemotherapy values remained within the normal range in all cases. In conclusion, adjuvant treatment of breast cancer patients with 6 cycles of the CNF combination, as judged by its effect on the measured indices, does not appear to be cardiotoxic. 相似文献
9.
M. G. Salem J. W. Crooke G. A. McLoughlin J. G. Middle W. H. Taylor 《Annals of the Royal College of Surgeons of England》1988,70(1):9-12
Eighteen male patients undergoing elective surgical reconstruction of the abdominal aorta were divided into two groups. Patients in Group I (nine) were given dopamine intravenously, in a dose of 2 micrograms/kg/min, during the first half of the period of cross-clamping, whilst those in Group II received dopamine during the second half. Each patient acted as his own control and for each, three periods were examined, namely: pre-clamp, clamping with dopamine and clamping without dopamine. Dopamine infusion during aortic clamping caused a significant rise in sodium output (P less than 0.01), potassium output (P less than 0.05), creatinine clearance (P less than 0.05) and urine output (P less than 0.05). We conclude that dopamine infusion during aortic clamping helps to protect the kidney from any deleterious effect of clamping. 相似文献
10.
Modification of human thrombin: effect on thrombomodulin binding 总被引:1,自引:0,他引:1
Thrombomodulin, an endothelial cell protein, binds thrombin with high affinity and alters thrombin from a procoagulant to an anticoagulant molecule. In this study, chemical and/or proteolytic modification of thrombin was carried out to identify the essential components required for its interaction with thrombomodulin. Modification of thrombin at the catalytic site serine and histidine residues, with Diisopropylfluorophosphate and Tosyl-L-lysine chloromethyl ketone, resulted in loss of clotting and amidolytic activity. Both Diisopropyl phosphoryl-thrombin and Tosyl-L-chloromethyl ketone-thrombin inhibited native-thrombin: thrombomodulin catalyzed protein C activation with Ki values of 5 nM and 6 nM respectively indicating no loss of affinity for thrombomodulin. Oxidation of tryptophan residues with N-bromosuccinimide or iodination of tyrosine residues of thrombin led to reduced clotting and amidolytic activity as well as a reduced ability to interact with thrombomodulin. Modification of arginine residues with Phenylglyoxal and 2,3,Butanedione led to loss of thrombomodulin binding affinity. Limited proteolysis of thrombin by trypsin yielded the derivative beta-thrombin which had also lost its ability to interact with thrombomodulin. Deglycosylation of thrombin did not alter its binding affinity for thrombomodulin. These results indicate that one or more tryptophan, arginine and tyrosine residues are essential for the recognition of thrombin by thrombomodulin whilst the carbohydrate side chain and the active site residues of the thrombin molecule are not involved in thrombomodulin binding. 相似文献