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51.
Y Unlü S Kele? N Becit C U Ko?o?ullari H Ko?ak E Bakan 《European journal of vascular and endovascular surgery》2005,30(3):315-318
OBJECTIVE: Several studies have shown a relation between hyperhomocysteinaemia and vascular disease. To assess the risk of deep-vein thrombosis (DVT) associated with hyperhomocysteinaemia, we studied plasma homocysteine levels in patients with deep-vein thrombosis and in normal control subjects. MATERIALS AND METHODS: We measured plasma homocysteine levels in 48 patients with deep-vein thrombosis and in 33 healthy controls matched to the patients according to age and sex. Plasma homocysteine levels were measured with high performance liquid chromatography and fluorescence detection. Hyperhomocysteinaemia was defined as a plasma homocysteine level about 15 micromol/L in both groups. The diagnosis of all patients with deep-vein thrombosis (n=48) was verified by Doppler ultrasonography. RESULTS: Plasma homocysteine levels were found to be increased in the deep-vein thrombosis group compared the control group (p<0.001, t-test). The mean plasma homocysteine level in the patients was 17.1 SD 5.13 micromol/L (range 6.4-31.3), and that in the controls was 9.0 SD 1.27 micromol/L (range 6.0-11.5). The association between elevated homocysteine levels and venous thrombosis was stronger among men than among women. CONCLUSIONS: The increased plasma homocysteine levels we have observed may have a causative role in the development of deep-vein thrombosis. 相似文献
52.
Mahmut Koç Ömer Yoldaş Yusuf Alper Kılıç Erdal Göçmen Tamer Ertan Hayrettin Dizen Mesut Tez 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》2007,392(5):581-585
Background and aims The aim of this study is to evaluate the predictive accuracy of different scoring systems on surgery for perforated peptic
ulcer referred to an academic department of general surgery in a tertiary reference center.
Patients and methods Seventy-five consecutive patients (Male/female ratio = 64:11; mean age, 44 years; range, 16–85) with perforated peptic ulcer
disease were investigated. Disease severity scores and mortality predictions were calculated using the collected data during
admission. Discrimination and calibration characteristics of each system, namely, the acute physiology and chronic health
evaluation II and III, the simplified acute physiology score II, and the mortality probability models (MPM) II, were determined
by using the area under receiver operating characteristics curve and the Hosmer–Lemeshow goodness-of-fit test, respectively.
Results Among the 75 patients included, there were eight (10.6%) mortalities. All systems had a reliable power of discrimination and
calibration. Among the systems tested, MPM II was the best performing as far as discrimination and calibration characteristics
were considered. The parameters of MPM II system that were related to systemic perfusion of the patient were significantly
positive in patients who died compared to those who survived.
Conclusions MPM II that predicted mortality at admission is better than the other systems in predicting mortality. Results also indicate
the importance of maintenance of systemic perfusion of the patient at the early phases of peptic ulcer perforation. 相似文献
53.
54.
Kaan Kirali Nihan Kayalar Tuncer Ko?ak Cevat Yakut 《European journal of cardio-thoracic surgery》2005,27(5):923-924
Many approaches for minimally invasive coronary bypass surgery are available and to further decrease the invasiveness, coronary artery bypass grafting has been performed under high thoracic epidural anesthesia without endotracheal intubation in the last years. Less invasive approach to coronary artery bypass graft operations is possible through combination of the high thoracic epidural anesthesia and a reversed-J sternotomy, and coronary revascularization can be accomplished without any additional technical difficulties and with a good exposure of both the left anterior descending artery and the left internal thoracic artery. This technique is less traumatic for patients and provides practical better oxygenation and shorter hospital stay. 相似文献
55.
Chien-Huang Lin Feng-Nien Ko Hisahi Ishii Tsutomu Ishikawa Ih-Sheng Chen Che-Ming Teng H.-P. Kuo 《Naunyn-Schmiedeberg's archives of pharmacology》1997,355(2):210-216
We investigated the effects of a novel platelet-activating factor (PAF) receptor antagonist, CIS-19 [cis-2-(3, 4-dimethoxyphenyl)-6-isopropoxy-7-methoxy-1-(N-methylformamido)-1,
2, 3, 4-tetrahydronaphthalene], on PAF-, histamine-, substance P- and antigen-induced bronchoconstriction and microvascular
leakage, as well as PAF- and antigen-induced bronchial hyperreactivity to methacholine in urethane-anesthetized guinea-pigs.
Administration of CIS-19 (0.5–5 mg/kg, i.v.) inhibited the increase in lung resistance induced by PAF (30 ng/kg, i.v.) in
a dose-dependent manner, but failed to inhibit the increase induced by histamine (30 μg/kg, i.v.) or substance P (6.5 μg/kg,
i.v.). CIS-19 (5 mg/kg, i.v.) did not inhibit the increase in lung resistance induced by ovalbumin (2 mg/kg, i.v.) in actively
sensitized guinea-pigs. PAF (30 ng/kg, i.v.)-induced microvascular leakage, measured by the extravasation of Evans blue dye,
was dose-dependently inhibited by CIS-19 (0.5–5 mg/kg, i.v.) in the trachea, main bronchi and intrapulmonary airways, but
it did not affect histamine (30 μg/kg, i.v.)- or substance P (6.5 μg/kg, i.v.)-induced microvascular leakage at all airway
levels. CIS-19 (2.5 and 5 mg/kg) did not affect ovalbumin (2 mg/kg, i.v.)-induced microvascular leakage in all airway levels
in actively sensitized guinea-pigs. CIS-19 (2.5 and 5 mg/kg, i.v.) significantly inhibited PAF-induced enhancement of the
bronchial response to methacholine, but had no effect on ovalbumin (0.05 mg/kg, i.v.)-induced bronchial hyperreactivity in
actively sensitized guinea-pigs. It is concluded that CIS-19 is a potent PAF receptor antagonist which inhibits PAF- but not
antigen-induced bronchoconstriction, microvascular leakage and bronchial hyperreactivity. These results suggest that PAF plays
little or no role in early airway responses following antigen challenge.
Received: 29 April 1996 / Accepted: 10 October 1996 相似文献
56.
57.
Although plasma cells are terminally differentiated B cells, neoplastic plasma cells frequently express not only pre-B cell antigen, but also megakaryocytic, myelomonocytic, or erythroid markers. Since morphologic diagnosis of plasmacytoma is based on the recognition of neoplastic cells closely resembling normal plasma cells, unusual morphologic variants of neoplastic cells associated with these aberrant immunohistochemical features frequently cause diagnostic difficulty. The authors report a case of plasmacytoma with cleaved nuclei and myelomonocytic features occurring in the clavicle. The tumor was composed of immature plasma cells showing irregular, cleaved, and multilobated nuclei and abundant cytoplasm with prominent eosinophilic granules. A few tumor cells showing recognizable plasmacytic differentiation were admixed within the tumor. Immunohistochemically, the tumor cells expressed CD45RB, CD68, lysozyme, myeloperoxidase and kappa light chain with focal positivity for lambda chain. Ultrastructurally, the tumor cells contained numerous membrane bound electron dense lysosomal granules, some of them resembling Auer rods, as well as rough endoplasmic reticula arranged in lamellated stacks. Small biopsied nasal mucosal tissue in same patient revealed well differentiated plasmacytoma composed of tumor cells showing round, eccentric nuclei devoid of marked nuclear cleavage and cytoplasmic granularity. Immunohistochemically, these cells were kappa(+), lambda(-), myeloperoxidase(-), lysozyme(-) and CD68(-). 相似文献
58.
59.
Georgia Robins Sadler Celine Marie Ko Jennifer Alisangco Bradley P Rosbrook Eric Miller Judith Fullerton 《Applied Nursing Research》2007,20(3):152-157
This article discusses issues to be considered by nurse researchers when groups should be used as the unit of randomization. Advantages and disadvantages are presented, with statistical calculations needed to determine the effective sample size. Examples of these concepts are presented using data from the Black Cosmetologists Promoting Health Program. Different hypothetical scenarios and their impact on sample size are also presented. Given the complexity of calculating the sample size when using groups as the unit of randomization, it is advantageous for researchers to work closely with statisticians when designing and implementing studies that anticipate the use of groups as the unit of randomization. 相似文献
60.
Tomasz Trojanowski Jerzy P ceszyński Krzysztof Turowski Stanisław Kamiński Igor Gościński Marian Reinfus Tadeusz Krzyszkowski Marek Pyrich Adam Bielawski Czesława Leszczyk Barbara Bendarzewska Andrzej Staszczak Halina Koźniewska 《Journal of neuro-oncology》1988,6(3):285-291
A prospective, randomized trial evaluates the effects of two postoperative treatment regimens on survival in 198 adult patients with supratentorial gliomas. All patients were irradiated with 6 000 rads after possibly radical removal of tumors. CCNU administration in the dosis of 100 mg/sq m of body surface every 6–8 weeks following surgery proved to have no significant effect on the survival of patients. The median survival time in patients receiving radiation therapy alone was 61±7 weeks, while in those receiving additional chemotherapy was 56±4 weeks. Tumor histological malignancy and patients age were found to be the only important prognostic factors, irrespective of the treatment modality.
Address for offprints: T Trojanowski, Department of Neurosurgery, Medical School, Jaczewskiego 8, 20-950 Lublin, Poland 相似文献