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101.
既往研究提示白细胞介素4(IL-4)、白细胞介素4受体(IL-4RA)基因与血清总IgE水平、过敏性疾病有关。然而结论并不一致。我们的研究目的在于调查华人、马来人及印度人中IL-4、IL-4RA的3个基因位点的基因型(C590T、Ile50Val、Q576R)与血清总IgE水平是否存在相关性。  相似文献   
102.
BACKGROUND: Coronary artery fistula (CAF) is an anomaly resulting in the steal phenomenon of coronary blood flow, which may cause morbidity or mortality. CAFs in Chinese patients after long-term follow-up of 15 years were retrospectively analyzed. METHODS AND RESULTS: From September, 1992 to August, 2007, 152 CAFs were detected in 28,210 coronary angiograms from 125 patients. Clinical and angiographic data of all patients were analyzed retrospectively. Two types of CAFs were characterized: type I in 99 patients with 124 solitary coronary to cardiac chamber or great vessel fistula; type II: 26 patients with 28 coronary artery--left ventricular multiple microfistulas. Single-, double-, and triple-CAFs were detected in 79%, 20%, and 1% of patients, respectively. Coexistent coronary lesions were noted in 41% of patients. Fistula-related symptoms included stable angina in 55, myocardial infarction in 2, heart failure in 2, sudden death with ventricular fibrillation in 1, and syncope in 1. Twenty-four patients had coexistent congenital anomalies. Only 9 patients underwent coronary intervention or/and surgery for CAFs. CONCLUSIONS: CAFs may cause trivial or lethal cardiac events, and may coexist with coronary lesion or congenital anomaly. Coronary to cardiac chamber or great vessel fistula and coronary-left ventricular multiple microfistulas have different morphologic and pathological phenomena.  相似文献   
103.
Erythroid failure in Diamond-Blackfan anemia is characterized by apoptosis   总被引:2,自引:4,他引:2  
Perdahl  EB; Naprstek  BL; Wallace  WC; Lipton  JM 《Blood》1994,83(3):645-650
Programmed cell death, also known as apoptosis, is frequently initiated when cells are deprived of specific trophic factors. To investigate if accelerated apoptosis contributes to the pathogenesis of Diamond- Blackfan anemia (DBA), a rare pure red blood cell aplasia of childhood, we studied the effect of erythropoietin (epo) deprivation on erythroid progenitors and precursors from the bone marrow of DBA patients as compared with hematologically normal controls. Apoptosis in response to epo deprivation was evaluated by enumeration of colony-forming unit- erythroid (CFU-E)- and burst-forming unit-erythroid (BFU-E)-derived colonies in plasma clot semisolid culture and by the identification of typical DNA oligosomes by gel electrophoresis from marrow mononuclear cells in liquid culture. In all DBA patients there was a marked decrease in CFU-E- and BFU-E-derived colony formation compared with normal controls at comparable time points of epo deprivation, with a complete loss of CFU-E-derived colonies in semisolid culture by 9 hours of epo deprivation versus 48 hours in controls. The BFU-E-derived colony response to epo deprivation displayed a similar pattern of decrement. Apoptotic changes assessed by the presence of characteristic DNA fragmentation began in the absence of epo deprivation and were readily detected within 3 hours of epo deprivation in DBA cultures versus 9 hours in controls. We conclude that DBA is characterized by accelerated apoptosis as measured by the loss of erythroid progenitor clonogenicity and increased progenitor and precursor DNA fragmentation leading to the formation of characteristic oligosomes, consistent with an intrinsic erythroid-progenitor defect in which increased sensitivity to epo deprivation results in erythroid failure.  相似文献   
104.
Value of CT in the diagnosis and management of gallstone ileus   总被引:15,自引:1,他引:15  
AIM: To retrospectively establish the diagnostic criteria of gallstone ileus on CT, and to prospectively apply these criteria to determine the diagnostic accuracy of CT to confirm or exclude gallstone ileus in patients who presented with acute small bowel obstruction (SBO). Another purpose was to ascertain whether the size of ectopic gallstones would affect treatment strategy. METHODS: Fourteen CT scans in cases of proved gallstone ileus were evaluated retrospectively by two radiologists for the presence or absence of previously reported CT findings to establish the diagnostic criteria. These criteria were applied in a prospective contrast enhanced CT study of 165 patients with acute SBO, which included those 14 cases of gallstone ileus. The hard copy images of 165 CT studies were reviewed by a different group of two radiologists but without previous knowledge of the patient's final diagnosis. All CT data were further analyzed to determine the diagnostic accuracy of gallstone ileus when using CT in prospective evaluation of acute SBO. The size of ectopic gallstone on CT was correlated with the clinical course. RESULTS: The diagnostic criteria of gallstone ileus on CT were established retrospectively, which included: (1) SBO; (2) ectopic gallstone; either rim-calcified or total-calcified; (3) abnormal gall bladder with complete air collection, presence of air-fluid level, or fluid accumulation with irregular wall. Prospectively, CT confirmed the diagnosis in 13 cases of gallstone ileus with these three criteria. Only one false negative case could be identified. The remaining 151 patients are true negative cases and no false positive case could be disclosed. The overall sensitivity, specificity and accuracy of CT in diagnosing gallstone ileus were 93%, 100%; and 99%, respectively. Surgical exploration was performed in 13 patients of gallstone ileus with ectopic stones sized larger than 3 cm. One patient recovered uneventfully following conservative treatment with an ectopic stone sized 2 cm in the long axis. CONCLUSION: Contrast enhanced CT imaging offered crucial evidence not only for the diagnosis of gallstone ileus but also for decision making in management strategy.  相似文献   
105.
Rectus sheath hematoma is an uncommon but well-described complication of a tussive paroxysm. It is an accumulation of blood within the sheath of the rectus abdominis secondary to disruption of the epigastric vessels or the rectus muscle and is often misdiagnosed as acute abdomen. Increases in the number of elderly patients and the use of therapeutic anticoagulation may increase the prevalence and severity of rectus sheath hematomas encountered in clinical practice. Expanding rectus sheath hematomas are occasionally refractory to conservative treatment and may require hemostatic intervention. Here, we describe the case of an 87-year-old woman who presented with two separate rectus sheath hematomas that were precipitated by a paroxysm of coughing. Repeated computed tomography showed two separate expanding rectus sheath hematomas, which were not accompanied by obvious contrast extravasation on angiography. Empiric left inferior epigastric artery embolization resulted in rapid hemodynamic stabilization, and the hematomas shrank gradually. Early empiric transcatheter arterial embolization may be appropriate for patients who are poor surgical candidates and have enlarging hematomas that are refractory to conservative treatment.  相似文献   
106.
107.
The present study investigated body position effects on transient evoked otoacoustic emission (TEOAE) recordings of clinical significance. Sixty adults (30 males, 30 females) were assessed using the Otodynamics ILO88 Analyzer in three positions (sitting, supine, and side-lying). Results indicated significant positional effects on the TEOAE parameters of A–B difference, noise, whole wave reproducibility, and response levels. These differences included higher noise levels in supine and side-lying positions in comparison to the upright sitting position. Lower whole wave reproducibility measurements, and higher response amplitudes, in the side-lying position compared with supine and seated positions were also observed. No significant effects were evident for signal-to-noise ratio or band reproducibility. Given the lack of significant body position effects on these latter parameters and the infrequent clinical use of the other parameters in isolation, there was no evidence to suggest the future need for major review of current pass/fail criteria or of the standard test protocol.  相似文献   
108.
109.
Retinoids are differentiation-inducing agents that exhibit multiple functions. Their activities are mediated through interaction with nuclear retinoic acid receptors (RAR) and retinoid X receptors (RXR). We have investigated the activities of synthetic retinoids on the growth of five gastric cancer cell lines. The effects of agonists selective for RARalpha, RARbeta and RARgamma (AM580, CD2019 and CD437, respectively) on cell growth were determined, in comparison to all-trans retinoic acid, by measuring total cellular DNA. AM580 and CD2019 had little or no effect on the growth of all five cell lines. In contrast, the RARgamma agonist CD437 inhibited cell growth up to 90-99% in both retinoic acid sensitive and resistant gastric cancer cells at a concentration of 1 microM. The growth suppression caused by CD437 was accompanied by the induction of apoptosis as judged by morphological criteria and DNA ladder formation. However, the extent of CD437-induced growth suppression was not correlated with RARgamma mRNA levels, which indicates that CD437 induces apoptosis in gastric cancer cells via an RARgamma independent pathway.  相似文献   
110.
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