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排序方式: 共有3398条查询结果,搜索用时 15 毫秒
31.
Mesoatrial shunt in Budd-Chiari syndrome 总被引:2,自引:0,他引:2
Emre A Kalayci G Ozden I Bilge O Acarli K Kaymakoğlu S Rozanes I Okten A Tekant Y Alper A Arioğul O 《American journal of surgery》2000,179(4):304-308
BACKGROUND: The operations with proven effects on survival in Budd-Chiari syndrome are shunt operations and liver transplantation. PATIENTS AND METHODS: Between 1993 and 1999 (June), 13 cases of Budd-Chiari syndrome have been treated surgically. Four cases had concomitant thrombosis of the inferior vena cava; the others had marked narrowing of the lumen due to the enlarged caudate lobe. Mesoatrial (n = 12) or mesosuperior vena caval (n = 1) shunts were constructed with ringed polytetrafluoroethylene grafts. RESULTS: The median portal pressure fell from 45 (range 32 to 55) to 20 (range 11 to 27) cm H(2)O (P <0.001). Two patients died in the early postoperative period. One patient who did not comply with anticoagulant treatment had a shunt thrombosis in the second postoperative year. The other 10 patients are alive without problems during a median 42 (range 1 to 76) months of follow-up. CONCLUSION: Mesoatrial shunt with a ringed polytetrafluoroethylene graft is effective in Budd-Chiari syndrome cases with thrombosis or significant stenosis in the inferior vena cava. 相似文献
32.
Ozcan C Ergün O Güçlü C Tümüklü M Alper H Erdener A 《Journal of pediatric surgery》2000,35(10):1523-1525
Parasitic or heterotopic conjoined twins are exceedingly rare, and these cases are referred to as "heteropagus" when there is a parasitic attachment in a nonduplicated fashion to any portion of the body. Epigastric heteropagus twinning refers to the attachment of the parasite to the epigastric region of the autosite. An unusual epigastric heteropagus case is presented with a rudimentary cardiopulmonary and also nearly complete gastrointestinal and genitourinary system of the parasite, and an organogenetic and vascular status of the previously reported cases are reviewed. The current case might be unique for the parasite having a cardiopulmonary development--although rudimentary--and this might be the reason that it has more complete organogenesis than the cases that have been presented previously in the literature. 相似文献
33.
Erdal Malatyalioglu Arif Kokcu Mehmet B Cetinkaya Tayfun Alper Migraci Tosun 《The journal of maternal-fetal & neonatal medicine》2006,19(6):353-356
OBJECTIVE: To analyze the cause of changing maternal mortality ratios (MMRs) in a tertiary women's health center in Turkey in the last eight years. MATERIALS AND METHODS: Charts of patients seen between 1998 and 2005 were retrospectively reviewed. Statistical analysis was performed using the Chi-square test. The results were accepted to be significant when the p value was <0.05. RESULTS: During this period, 27 pregnancy-related deaths were identified via hospital death records. The MMR was found to have decreased in rate by approximately 50% from 822.2/100,000 live births in the previous report including the years 1978-1997 to 412.0/100,000 during the last eight years (p < 0.01). Pregnancy-induced hypertension was still the most frequent cause of maternal death. The decrease in MMR was due to the decrease in the ratio of maternal infection (26.4% in 1978-1997 to 7.4% in 1998-2005, p < 0.01). CONCLUSION: Although treatment in the antenatal care and health service has decreased maternal deaths, it was discovered that the MMR has not reached the optimum levels found in developed countries in the last eight years. Also the percentage of direct obstetric deaths (with the exception of those caused by infection) showed no change and was similar to that found in the previous report (1978-1997). 相似文献
34.
F Alper H Kaynar M Kantarci O Onbas P Polat F Erdogan M Akgun A Okur 《Journal of Medical Imaging and Radiation Oncology》2005,49(1):53-56
We describe a 9-year-old child with a history of trichoptysis caused by intrapulmonary teratoma and we present the CT and MRI findings of the teratoma. A heterogeneous mass containing cystic and solid elements was detected on both CT and MRI scans. Histopathological examination confirmed the diagnosis of teratoma. Teratomas arising from lung parenchyma, as in this case, are extremely rare in childhood. In the thoracic region, the most common localization of teratomas is the anterior mediastinal compartment. We also discuss the CT and MRI findings and the differential diagnosis of teratomas. 相似文献
35.
Eren Erdogdu Berker Ozkan Salih Duman Melek Agkoc Sukru Mehmet Erturk Murat Kara Alper Toker 《The clinical respiratory journal》2022,16(5):361
BackgroundThe management of a solitary pulmonary nodule is a challenging issue in pulmonary disease. Although many factors have been defined as predictors for malignancy in solitary pulmonary nodules, the accurate diagnosis can only be established with the permanent histological diagnosis.ObjectiveWe tried to clarify the possible predictors of malignancy in solitary pulmonary nodules in patients who had definitive histological diagnosis.MethodsWe made a retrospective study to collect the data of patients with solitary pulmonary nodules who had histological diagnosis either before or after surgery. We made a statistical analysis of both the clinic and radiological features of these nodules with respect to malignancy both in contingency tables and with logistic regression analysis.ResultsWe had a total of 223 patients with a radiological diagnosis of solitary pulmonary nodule. Age, smoking status and pack years of smoking, maximum standardized uptake value (SUVmax), and radiological features such as solid component, spiculation, pleural tag, lobulation, calcification, and higher density were significant predictors of malignancy in contingency tables. Age, smoking status and smoking (pack/year), SUVmax, and radiological features including spiculation, pleural tag, lobulation, calcification, and higher density were the significant predictors in univariate analysis. However, multivariate analysis revealed only SUVmax greater than 2.5 (p < 0.0001), spiculation (p = 0.009), and age older than 61 years (p = 0.015) as the significant predictors for malignancy.ConclusionAge, SUVmax, and spiculation are the independent predictors of malignancy in patients with solitary pulmonary nodules. 相似文献
36.
用离体大鼠肝脏灌流方法,研究了胆碱酯酶抑制剂CXN的生物转化过程。径HPLC分离纯化及光谱分析,鉴定了CXN的六个脂溶性代谢产物的化学结构。产物Ⅰ为CXN原形,其余均为氧化产物。其中产物Ⅲ尚保留部分抑酶活力,而产物Ⅱ,Ⅴ及Ⅵ对小鼠全脑胆碱酯酶的抑酶活力明显下降。另外还观察到,代谢产物Ⅱ及Ⅴ对小鼠的急性毒性也明显减小。 相似文献
37.
Hemodynamic shear stress and its role in atherosclerosis 总被引:59,自引:0,他引:59
Atherosclerosis, the leading cause of death in the developed world and nearly the leading cause in the developing world, is associated with systemic risk factors including hypertension, smoking, hyperlipidemia, and diabetes mellitus, among others. Nonetheless, atherosclerosis remains a geometrically focal disease, preferentially affecting the outer edges of vessel bifurcations. In these predisposed areas, hemodynamic shear stress, the frictional force acting on the endothelial cell surface as a result of blood flow, is weaker than in protected regions. Studies have identified hemodynamic shear stress as an important determinant of endothelial function and phenotype. Arterial-level shear stress (>15 dyne/cm2) induces endothelial quiescence and an atheroprotective gene expression profile, while low shear stress (<4 dyne/cm2), which is prevalent at atherosclerosis-prone sites, stimulates an atherogenic phenotype. The functional regulation of the endothelium by local hemodynamic shear stress provides a model for understanding the focal propensity of atherosclerosis in the setting of systemic factors and may help guide future therapeutic strategies. 相似文献
38.
Ceyhan M Yildirim I Tekeli A Yurdakok M Us E Altun B Kutluk T Cengiz AB Gurbuz V Barin C Bagdat A Cetinkaya D Gur D Tuncel O 《American journal of infection control》2008,36(6):453-457
Three clusters of Chryseobacterium meningosepticum infections in a tertiary health center in July 2006 and January 2007 involving 8 newborns and 5 older children were investigated. The index patient was from the neonatal intensive care unit, and the older patients were from other pediatric wards. Cultures were obtained from the environment and from health care workers' hands as part of an outbreak investigation. C meningosepticum was isolated from hand cultures obtained from a senior resident and from environmental cultures obtained from powdered infant formula, an electrical button, a computer keyboard, phone, a doorknob, and an Ambu bag. Antibiogram typing and enterobacterial repetitive intergenic consensus sequence polymerase chain reaction indicated that all of the isolates were epidemiologically related. Nine patients improved on antimicrobial treatment, and 4 premature infants died after the infection. C meningosepticum is a well-known etiologic agent for nosocomial infections involving newborns and immunocompromised patients. Wet and dry environmental surfaces and equipment may act as a source or play a role in disseminating the microorganism. Outbreaks may be controlled with strong emphasis on infection control measures. 相似文献
39.
de Haas M; Kerst JM; van der Schoot CE; Calafat J; Hack CE; Nuijens JH; Roos D; van Oers RH; von dem Borne AE 《Blood》1994,84(11):3885-3894
In four healthy volunteers, we analyzed in detail the immediate in vivo effects on circulating neutrophils of subcutaneous administration of 300 micrograms of granulocyte colony-stimulating factor (G-CSF). Neutrophil activation was assessed by measurement of degranulation. Mobilization of secretory vesicles was shown by a decrease in leukocyte alkaline phosphatase content of the circulating neutrophils. Furthermore, shortly postinjection, Fc gamma RIII was found to be upregulated from an intracellular pool that we identified by immunoelectron microscopy as secretory vesicles. Intravascular release of specific granules was shown by increased plasma levels of lactoferrin and by upregulation of the expression of CD66b and CD11b on circulating neutrophils. Moreover, measurement of fourfold elevated plasma levels of elastase, bound to its physiologic inhibitor alpha 1- antitrypsin, indicated mobilization of azurophil granules. However, no expression of CD63, a marker of azurophil granules, was observed on circulating neutrophils. G-CSF--induced mobilization of secretory vesicles and specific granules could be mimicked in whole blood cultures in vitro, in contrast to release of azurophil granules. Therefore, we postulate that the most activated neutrophils leave the circulation, as observed shortly postinjection, and undergo subsequent stimulation in the endothelial microenvironment, resulting in mobilization of azurophil granules. Our data demonstrate that G-CSF should be regarded as a potent immediate activator of neutrophils in vivo. 相似文献
40.
Sari I Altuntas F Hacioglu S Kocyigit I Sevinc A Sacar S Deniz K Alp E Eser B Yildiz O Kaynar L Unal A Cetin M 《American journal of hematology》2008,83(4):334-339
The aim of the study is to review the clinical manifestations and the hematological findings of brucellosis and pancytopenia, with or without hematological malignancies. The records of 202 patients with brucellosis were evaluated retrospectively. Among these cases of brucellosis seen in a 6 year period between April 1999 and June 2005, 30 patients with pancytopenia were identified. The most common manifestation was fever, followed by weight loss, anorexia, malaise, arthralgia, and hepatosplenomegaly. Bone marrow biopsies revealed hypercellularity or normocellularity. The most common findings in the bone marrow evaluation were histiocytic hemophagocytosis and granulomas. Among all cases, we diagnosed 5 hematological malignancies (1 acute myelogenous leukemia, 2 acute lymphoblastic leukemia, and 2 multiple myeloma) concurrently with brucellosis. The clinical symptoms and findings were similar in patients with and without malignancies. In cases with malignancies, the bone marrow biopsy revealed predominant primary disease involvement. Significant increases in ESR and CRP, severe anemia and thrombocytopenia were observed in patients with malignancies. Peripheral blood counts in patients without malignancies returned to normal after antibiotic treatment for brucellosis. However, pancytopenia in two patients with malignancies did not recover because of primary resistant disease. We conclude that while histiocytic hemophagocytosis may be considered as a major cause of pancytopenia, leukemic infiltration can also be an extreme and unusual cause of pancytopenia in patients in whom brucellosis was concurrently diagnosed with hematological malignancies. 相似文献