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21.
22.
Should cervical ultrasonography be a routine staging investigation for lung cancer patients with impalpable cervical lymph nodes? 总被引:3,自引:0,他引:3
Alan D L Sihoe Tak Wai Lee Anil T Ahuja Anthony P C Yim 《European journal of cardio-thoracic surgery》2004,25(4):486-491
OBJECTIVES: Detection of cervical N3 lymph nodes is currently not a routine preoperative investigation for lung cancer patients. We designed a study to assess if the frequency and accuracy of detection of metastatic cervical lymph nodes using cervical ultrasonography (US) and fine needle aspiration (FNA) justify their routine use in all lung cancer patients with impalpable cervical lymph nodes. METHODS: Fifty patients with suspected and potentially operable non-small cell lung cancer were enrolled. Patients with palpable cervical lymph nodes were excluded. In addition to routine preoperative investigations, all patients received cervical US to determine the presence of cervical lymph nodes. Nodes suspicious of harboring malignancy according to a specific set of sonographic criteria (which include shape, echogenicity, nodal architecture, and vascular patterns) were subjected to biopsy by ultrasound-guided FNA. RESULTS: Normal cervical lymph nodes were detected by cervical US in 30 patients (60%). Cervical lymph nodes suspicious of harboring malignancy were detected in 10 patients (20%). FNA confirmed cervical nodal metastasis in four of these patients (8%). The TNM staging of two patients (4%) was revised up to stage IIIb as a result, excluding them from further surgery. Cost analysis suggests this technique to be cost-effective when used as a routine preoperative investigation to exclude patients from unnecessary surgical intervention. No mortality or complications were encountered in all patients. CONCLUSIONS: Cervical US and FNA is a safe and cost-effective method of evaluating the status of impalpable cervical lymph nodes in lung cancer patients. Further study is warranted to establish the role of cervical US and FNA in lung cancer staging algorithms. 相似文献
23.
Cystic or cyst-like neck masses form a unique category within head and neck radiology with unique differential diagnoses. The precise anatomical location and imaging appearances are important for accurate diagnosis and formulating the differential diagnoses of cystic lesions in the neck. In vast majority of cases ultrasound, sometimes supplemented by fine-needle aspiration cytology (FNAC), is adequate for pre-treatment assessment. For large, deep-seated lesions assessment using magnetic resonance imaging (MRI) or computed tomography (CT) often provides useful supplementary information. Radiologists should be aware of imaging findings of common cystic neck masses to help in their appropriate management. 相似文献
24.
King AD Ma BB Yau YY Zee B Leung SF Wong JK Kam MK Ahuja AT Chan AT 《The British journal of radiology》2008,81(964):291-298
The aim of this study was to determine whether the use of whole-body (18)F-fluoro-2-deoxy-D-glucose ((18)F-FDG) positron emission tomography (PET)/CT alters staging and management of nasopharyngeal carcinoma (NPC) when compared with current staging practice. 52 patients with Stage III-IV NPC without distant metastases on chest X-ray/CT, abdominal ultrasound or bone scan were recruited for the study. Whole-body (18)F-FDG PET/CT and MRI of the head and neck were performed. The scans were compared for extent of the primary tumour (PT), cervical nodal metastases (CNM) and distant metastases (DM). Any discordance in results was assessed with respect to staging and impact on management. MRI and (18)F-FDG PET/CT scans were discordant in 28 (54%) patients. There was discordance in the extent of PT at 28 sites; in all sites, MRI showed more extensive tumour involving the nasopharynx (n = 8), skull base (n = 14), brain (n = 4) and orbit (n = 2). There was also variation among the extent of CNM in four nodes of the retropharyngeal region, with the nodes being positive on MRI. (18)F-FDG PET /CT did not identify any additional distant metastases but did identify a second primary tumour in the colon. The additional use of (18)F-FDG PET/CT did not "up-stage" the overall stage or change management in any patient. In conclusion, there is discordance between MRI and (18)F-FDG PET/CT, and the additional use of (18)F-FDG PET/CT for the current assessment of NPC at diagnosis does not appear to be justified in this cohort of patients. 相似文献
25.
Rajeev B. Ahuja Sameek Bhattacharya Ashish Rai 《Burns : journal of the International Society for Burn Injuries》2009
The incidence of severe burn is extremely high in the Low and Middle Income Countries with an estimated 90% of the world incidence of which 50% is in South East Asia. Through an earlier analysis of 11,196 burn admission over 8 years (1993–2000—Phase I) to our burn unit we established the endemic nature of the injury [Ahuja RB, Bhattacharya S. An analysis of 11,196 burn admissions and evaluation of conservative management techniques. Burns 2002;28:555–61]. A continued analysis of 5566 burn admissions over the next 7 years (2001–2007—Phase II) and its comparison with the Phase I reveals a significant change in the epidemiological profile. The average yearly admissions have fallen by 43.14%, from 1399.5 patients in Phase I to 795.14 patients in Phase II. This fall in average yearly admissions is predominant in the age group 16–35 years (52.61% decline) and 36–55 years (46.51% decline). The overall female to male ratio has also changed from 1.26:1 to 0.91:1. However, the overall mean %TBSA burn has reduced only mildly from 49.12% TBSA in Phase I to 44.39% in Phase II. During Phase II there was also a significant decline of 46.93% and 56.25% in the yearly admission of flame and scald burn respectively. Non-intentional incidents still remain the main mode of injury accounting for 87.12% in Phase I and 89.89% in Phase II. But, the yearly admissions of non-intentional burns fell from 1219.25 in Phase I to 714.71 in Phase II, which is a significant drop of 41.38%. Kitchen continues to dominate as the main location for flame incidents, but the yearly admission rate from kitchen accidents dropped from 897.5 patients in Phase I to 368.43 patients in Phase II. At the same time, liquefied petroleum gas (LPG) leaks which accounted for only 0.72% of all kitchen accidents in Phase I rose to 10.74% in Phase II. Another redeeming feature is the reduction in overall mortality from 51.8% in Phase I to 40.20% in Phase II. Interestingly, a very significant negative correlation exists (being significant at 0.01 level—2 tailed) between burn admissions and the yearly per-capita income of Delhi, from 1993 to 2005, to prove that the incidence and profile of burns directly reflects the economic development of the society. We see this as the first long term study from a burn unit of a developing country to directly reflect this association of burn incidence and its changing profile with economic prosperity. 相似文献
26.
Palaniappan Lakshmanan Alwyn Jones Jwalant Mehta Sashin Ahuja Paul Rhys Davies John P. Howes 《The spine journal》2009,9(12):1003-1009
Background contextTreatment of unstable burst fractures in the dorsolumbar spine still remains controversial. Surgical stabilization has been aimed to prevent long-term back pain and progression of deformity.PurposeThis study was aimed to analyze the degree of loss of correction of the angle of kyphosis with pedicle screw instrumentation in place and the components responsible for the recurrence of kyphosis after surgical stabilization of dorsolumbar A3 fractures and to assess the return of functional capacity in these patients.Study designRetrospective study.Patient sampleThis study involves 26 patients who had dorsolumbar unstable burst fractures (Arbeitsgemeinschaft für Osteosynthesefragen type A3).Outcome measuresRadiological assessment at injury, immediate postoperative period, and most recent follow-up along with functional assessment using short form 36 (SF-36) and return to work.MethodsAll the patients had posterior pedicle screw instrumentation without fusion for unstable dorsolumbar burst compression (A3) fractures. The mean follow-up period was 25.5 months. All of them had their fractures stabilized with Universal Spinal System (Synthes, Welwyn Garden City, UK) Fracture System. Serial standing lateral radiographs were taken from the immediate postoperative period to the most recent follow-up. The angle of kyphosis; the heights of the discs above and below the fractured vertebra; and the heights of the vertebral bodies above, at, and below the fractured level were measured. The height at each level was measured in three segments (anterior, middle, and posterior). The values were normalized to avoid discrepancies while comparing radiographs. The difference in the height of each segment measured between the immediate postoperative period and the most recent follow-up was computed.ResultsThe mean angle of kyphosis was 6.3±8.9 in the immediate postoperative period and 15.7±6.7 at the most recent follow-up (p<.001). The mean patient function score from SF-36 was 52.3%, and the mean pain score was 44.9%. There was no relationship to the loss of correction angle of kyphosis to the patient function score (r=0.06, p=.76) and the pain score (r=0.11, p=.58). The correlation between the corresponding difference in the height of each segment and the degree of loss of correction of the angle of kyphosis showed positive correlation to the decrease in the anterior and middle segment heights at the fractured vertebral level.ConclusionThere is a progressive loss of correction of the angle of kyphosis after posterior stabilization with instrumentation even without implant removal that mainly corresponds to the decrease in the anterior segment height of the fractured vertebral body. 相似文献
27.
BACKGROUND: The Centers for Disease Control and Prevention (CDC) recommends hepatitis B virus (HBV) immunization for all hemodialysis (HD) patients because they are at high risk of infection. Several studies have shown that the development of protective antibody titers after HBV vaccination is much lower in HD patients. We hypothesized that human immunodeficiency virus (HIV) infection in patients with end-stage renal disease (ESRD) would further impair the immune response to hepatitis B vaccination. METHODS: We performed a retrospective cohort study of patients undergoing long-term hemodialysis from 1990 to 2002 at the United States-based dialysis facilities of Gambro Corporation, North America. The response rate defined as an increase in anti-HBs levels >/=10 mIU/L after a month of the third dose of HBV vaccination was determined in HIV-infected and a randomly selected group of ESRD patients. The demographic information, laboratory data, and hepatitis B surface antibody (anti-HBs) titers were recorded from the Gambro Corporation database on these patients. RESULTS: Of the 347 adult HIV ESRD patients, 116 received three doses of recombinant hepatitis B vaccination. Seventy percent were male, and the majority (86%) were black. Of the 116 patients who received three doses of HBV vaccination, 62 (53.4%) developed protective antibody titers. This was comparable to the response rate of 50.4% in the randomly selected 220 non-HIV hemodialysis patients. Among HIV ESRD patients, the mean hemoglobin (Hgb) was higher in patients who developed protective antibody titers (Hgb 11.61 +/- 2 vs. 10.55 +/- 1.86, P value <0.01). On multivariate logistic regression analysis, higher Hgb was associated with protective antibody titers (odds ratio: 1.34, 95% CI 0.99-1.72). Seventy percent of the HIV-infected responders maintained protective antibody titers 6 months after vaccination. CONCLUSION: Hepatitis B vaccination should be offered to all HIV-infected ESRD patients because over half of the patients with HIV and ESRD can develop protective antibodies. 相似文献
28.
R K Saran K Bhandari V S Narain R C Ahuja V K Puri R Thakur S Dwivedi M Hasan 《International journal of cardiology》1990,28(2):209-213
We report the results of a randomized controlled trial of intravenous streptokinase in a subset of patients with unstable angina. Seventy-six patients were admitted with prolonged (more than 20 minutes) angina at rest of less than 3 weeks onset. Fifty-two patients continued to have more than 3 episodes of prolonged angina in 48 hours on medical therapy with metoprolol, isosorbide dinitrate, nifedipine and intravenous nitroglycerin. Forty-eight patients consented to enter the study and were randomized into two groups. The first group, of 24 patients, received 1.5 million units of streptokinase infusion and the second group, also of 24 patients, received a placebo. Pain relief within 48 hours was achieved in 19/24 (79.1%) patients after streptokinase infusion as compared to 9/24 (37.5%) of the controls (P less than 0.05). Approximately 90% (17/19) of patients responding to streptokinase therapy were relieved of chest pain within the first six hours as against none in the controls. The incidence of acute myocardial infarction within six months was 12.5% (3/24) in those receiving streptokinase and 25% (6/24) in the controls. Mortality at six months stood at 8.33% (2/24) in the treated patients and 16.6% (4/24) in the controls. Intravenous streptokinase thus appears to be of benefit in patients with angina at rest of recent onset which does not respond to conventional medical therapy. 相似文献
29.
Kalaiyarasan Thiyagarajan Vijay K. Bharti Shruti Tyagi Pankaj K. Tyagi Anami Ahuja Krishna Kumar Tilak Raj Bhuvnesh Kumar 《RSC advances》2018,8(41):23213
For nearly a decade, silver nanoparticles (AgNPs) have been the most prevalent commercial nanomaterials products widely used in different biomedical applications due to their broad-spectrum antimicrobial activity. However, their poor long-term stability in different environments, namely, pH, ionic strength, and temperature, and cytotoxicity toward mammalian cells has restricted their more extensive applications. Hence, there is urgent need to develop highly biocompatible, non-toxic, and stable silver nanoparticles for wide-ranging environments and applications. In the present study, a simple, sustainable, cost-effective and green method has been developed to prepare highly stable aqueous colloidal silver nanoparticles (AgNPs-EW) using the ovalbumin, ovotransferrin, and ovomucoid of egg-white as reducing and capping agents accomplished under the irradiation of direct sunlight. Then, we evaluated the effects of freezing–drying (lyophilization) and freeze–thaw cycles on the stability of AgNPs-EW in aqueous solution under visual inspection, transmission electron microscopy, and absorbance spectroscopy. In addition, we studied the antibacterial activity against Salmonella typhimurium and Escherichia coli, carried out biocompatibility studies on chicken blood, and tested acute, chronic toxicity in Drosophila melanogaster. The results suggest that AgNPs-EW did not aggregate upon freeze-thawing and lyophilization, thus exhibiting remarkable stability. The antibacterial activity results showed that the AgNPs-EW had the highest antibacterial activity, and the minimum inhibitory concentration (MIC) of AgNPs-EW for E. Coli and S. typhimurium were 4 and 6 μg ml−1, respectively. The biocompatibility study revealed that the AgNPs-EW did not induce any hemolytic effect or structural damage to the cell membranes of chicken erythrocytes up to a concentration of 12 μg ml−1. Similarly, no acute and chronic toxicity was observed on melanization, fecundity, hatchability, viability, and the duration of development in the 1st generation of Drosophila melanogaster at the concentration range of 10 mg L−1 to 100 mg L−1 of AgNPs-EW, and all the flies completed their full developmental cycle. Therefore, the present study successfully demonstrated the green and sustainable preparation of non-toxic AgNPs-EW having good biocompatibility, enhanced colloidal stability, and antibacterial activity. Hence, the synthesized AgNPs-EW could be used for the development of an antimicrobial formulation for controlling microbial infection.For nearly a decade, silver nanoparticles (AgNPs) have been the most prevalent commercial nanomaterials products widely used in different biomedical applications due to their broad-spectrum antimicrobial activity. 相似文献
30.
A splicing mutation accounts for the lack of p53 gene expression in a CML blast crisis cell line: a novel mechanism of p53 gene inactivation 总被引:2,自引:0,他引:2
Alterations of the p53 anti-oncogene have recently been found to occur frequently in the blast crisis of chronic myelocytic leukaemia. The p53 gene may be altered by gross structural alterations or by point mutations in the coding sequence. We now report a novel mechanism of gene inactivation in a blast crisis cell line where a mutation in a splice donor site at the 5' end of the fifth intron of the gene interrupts RNA processing and gene expression. 相似文献