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排序方式: 共有4248条查询结果,搜索用时 15 毫秒
41.
WBG Macdonald AP Patrikeos RI Thompson BD Adler AA Van Der Schaaf 《Journal of Medical Imaging and Radiation Oncology》2005,49(1):32-38
The present study compared the accuracy of ventilation perfusion scintigraphy (VQS) and CT pulmonary angiography (CTPA) for the diagnosis of pulmonary embolism. This was a prospective observational study of 112 patients with suspected pulmonary embolism (PE) who could be studied with both investigations within 24 h. Results were compared to final diagnosis at completion of 6-month follow up, using receiver operating characteristic (ROC) analysis. Pulmonary embolism was diagnosed in 27 referred patients (24%). The sensitivity and specificity of VQS and CTPA were similar to that reported from the literature. A normal VQ scan had the highest negative predictive value (100%), while a high-probability VQ scan had the highest positive predictive value (92%). There was no overall difference (area under the ROC curve (AUC)) between VQS (AUC (95% CI) = 0.82 (0.75,0.89)) and CTPA (AUC = 0.88 (0.81,0.94)) for the diagnosis of PE. Among patients with abnormal chest X-rays, CTPA (AUC 0.90 (0.83,0.97)) appeared somewhat better than VQS (AUC 0.78 (0.68,0.88)) but this difference did not reach statistical significance. In this instance, CTPA is at least as accurate as VQS and may provide an opportunity to make alternative diagnoses. 相似文献
42.
Xiaoxia Guo Bing Xu Shuchita Pandey Elisabeth Goessl James Brown Angel L. Armesilla John L. Darling Weiguang Wang 《Cancer letters》2010
Most of the gemcitabine (dFdC) resistant cell lines manifested high NFκB activity. The NFκB activity can be induced by dFdC and 5-FU exposure. The chemosensitizing effect of disulfiram (DS), an anti-alcoholism drug and NFκB inhibitor, and copper (Cu) on the chemoresistant cell lines was examined. The DS/Cu complex significantly enhanced the cytotoxicity of dFdC (resistant cells: 12.2–1085-fold) and completely reversed the dFdC resistance in the resitant cell lines. The dFdC-induced NFκB activity was markedly inhibited by DS/Cu complex. The data from this study indicated that DS may be used in clinic to improve the therapeutic effect of dFdC in breast and colon cancer patients. 相似文献
43.
Agarwal A Chowdhary P Das V Srivastava A Pandey A Sahu MT 《The journal of obstetrics and gynaecology research》2007,33(5):651-654
AIM: Management of post cesarean pregnancy continues to be a dilemma. The present study was undertaken to evaluate the outcome of such pregnancies in a resource constrained setting so that an appropriate management protocol can be decided. METHODS: An observational study was conducted in the Department Of Obstetrics And Gynecology, King George's Medical University, Lucknow, India. The outcome of all of the women admitted with pregnancy with a previous cesarean section was noted. RESULTS: A total number of 447 women with a post cesarean pregnancy underwent delivery. These comprised 13.7% of total deliveries over the same period. 124 women (27.7%) had successful vaginal delivery while 323 (72.3%) had a repeat cesarean section. Maternal morbidity and perinatal mortality were both significantly higher in the vaginal delivery group (P = 0.00211 and P = 0.0426, respectively). CONCLUSIONS: Vaginal birth after cesarean (VBAC) is associated with higher maternal morbidity and perinatal mortality. Therefore the decision for VBAC must be taken only after proper consideration and counseling of the couple. 相似文献
44.
S. Pandey P. Pandey G. Tiwari R. Tiwari A. K. Rai 《Indian journal of pharmaceutical sciences》2012,74(1):86-90
A simple, accurate and sensitive spectroscopic method has been proposed for the assay of ciprofloxacin in tablet by least square treatment of fourier transform infrared spectrometric data obtained at the wavenumber corresponding to the carbonyl group centered at 1707 cm-1. The method involves the extraction of the active ingredient with methanol followed by phosphate buffer pH 6.0. The excipients in the commercial tablet preparation did not interfere with the assay. The specifity, linearity, detection limits, precision and accuracy of the calibration curve, drug extraction, infrared analysis and data manipulation were determined in order to validate the method. Moreover, the statistical results were compared with other methods for quantification of ciprofloxacin. 相似文献
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47.
Sher Bahadur Pun Kishor Pandey Rajesh Shah 《The American journal of tropical medicine and hygiene》2013,88(2):227-229
The government of Nepal has committed to eliminate visceral leishmaniasis (VL) by 2015. The expansion of VL into new areas would constitute a major obstacle to achieving this goal. We report a series of autochthonous VL cases from areas currently considered non-endemic, mostly in hilly regions of Nepal. 相似文献
48.
Twenty-five surgically confirmed soft-tissue lesions of the hand were examined prospectively by real-time ultrasound. Use of sonography enabled a reliable diagnosis of the cystic or solid nature of soft-tissue lesions, an accurate estimation of the volume, and precise three-dimensional localization of the abnormality. Sonography also facilitated the location of foreign bodies. Assessment of anatomic relationships of these lesions to tendons and surrounding structures by real-time sonography during palpation, flexion, and/or extension also aided in the surgical approach. 相似文献
49.
Defective opsonization in multiple myeloma 总被引:1,自引:0,他引:1
The mechanisms responsible for the unusual susceptibility of multiple myeloma (MM) patients to infections are incompletely defined. Since MM is associated with decreased production of normal serum proteins, we investigated the possibility that the production of opsonins might also be impaired. The neutrophil chemiluminescence assay of opsonization was used to evaluate the ability of serum from patients with MM to opsonize zymosan. It was found that sera from 18 MM patients exerted only 50% +/- 2.5% (mean +/- SEM) of the opsonic activity found in 18 control sera (p less than 0.001). In mixture experiments, untreated normal serum completely restored the opsonic activity of MM serum, suggesting a deficiency of opsonic factors rather than an inhibitor. In other mixture experiments, heat-inactivated normal serum only partially corrected the opsonic defect in MM serum. Serum from three patients had low C3 levels, and treatment of particles with these resulted in a greater opsonic defect than the patient population as a whole (p less than 0.02). No correlation between the opsonic defect and infections was established over an 18-mo period. These data suggest that MM serum lacks both heat-stable and heat-labile opsonic activity, the direct clinical significance of which remains to be clarified. However, these studies support the concept that defective host resistance in MM may be multifactoral, combining opsonic abnormalities with other defects previously described. 相似文献
50.
The plaque lipid lysophosphatidic acid stimulates platelet activation and platelet-monocyte aggregate formation in whole blood: involvement of P2Y1 and P2Y12 receptors 总被引:7,自引:0,他引:7 下载免费PDF全文
Despite the fact that lysophosphatidic acid (LPA) has been identified as a main platelet-activating lipid of mildly oxidized low-density lipoprotein (LDL) and human atherosclerotic lesions, it remains unknown whether it is capable of activating platelets in blood. We found that LPA at concentrations slightly above plasma levels induces platelet shape change, aggregation, and platelet-monocyte aggregate formation in blood. 1-alkyl-LPA (16:0 fatty acid) was almost 20-fold more potent than 1-acyl-LPA (16:0). LPA directly induced platelet shape change in blood and platelet-rich plasma obtained from all blood donors. However, LPA-stimulated platelet aggregation in blood was donor dependent. It could be completely blocked by apyrase and antagonists of the platelet adenosine diphosphate (ADP) receptors P2Y1 and P2Y12. These substances also inhibited LPA-induced aggregation of platelet-rich plasma and aggregation and serotonin secretion of washed platelets. These results indicate a central role for ADP-mediated P2Y1 and P2Y12 receptor activation in supporting LPA-induced platelet aggregation. Platelet aggregation and platelet-monocyte aggregate formation stimulated by LPA was insensitive to inhibition by aspirin. We conclude that LPA at concentrations approaching those found in vivo can induce platelet shape change, aggregation, and platelet-monocyte aggregate formation in whole blood and suggest that antagonists of platelet P2Y1 and P2Y12 receptors might be useful preventing LPA-elicited thrombus formation in patients with cardiovascular diseases. 相似文献