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排序方式: 共有2170条查询结果,搜索用时 656 毫秒
1.
Usha Patel Manish Pandey Sadhana Kannan Tanuja A. Samant Poonam Gera Neha Mittal Swapnil Rane Asawari Patil Vanita Noronha Amit Joshi Vijay M. Patil Kumar Prabhash Manoj B. Mahimkar 《British journal of cancer》2020,123(12):1757
Background Anti-EGFR-based therapies have limited success in HNSCC patients. Predictive biomarkers are greatly needed to identify the patients likely to be benefited from these targeted therapies. Here, we present the prognostic and predictive association of biomarkers in HPV-negative locally advanced (LA) HNSCC patients.Methods Treatment-naive tumour tissue samples of 404 patients, a subset of randomised Phase 3 trial comparing cisplatin radiation (CRT) versus nimotuzumab plus cisplatin radiation (NCRT) were analysed to evaluate the expression of HIF1α, EGFR and pEGFR by immunohistochemistry and EGFR gene copy change by FISH. Progression-free survival (PFS), locoregional control (LRC) and overall survival (OS) were estimated by Kaplan–Meier method. Hazard ratios were estimated by Cox proportional hazard models.Results Baseline characteristics of the patients were balanced between two treatment groups (CRT vs NCRT) and were representative of the trial cohort. The median follow-up was of 39.13 months. Low HIF1α was associated with better PFS [HR (95% CI) = 0.62 (0.42–0.93)], LRC [HR (95% CI) = 0.56 (0.37–0.86)] and OS [HR (95% CI) = 0.63 (0.43–0.93)] in the CRT group. Multivariable analysis revealed HIF1α as an independent negative prognostic biomarker. For patients with high HIF1α, NCRT significantly improved the outcomes [PFS:HR (95% CI) = 0.55 (0.37–0.82), LRC:HR (95% CI) = 0.55 (0.36–0.85) and OS:HR (95% CI) = 0.54 (0.36–0.81)] compared to CRT. While in patients with low HIF1α, no difference in the clinical outcomes was observed between treatments. Interaction test suggested a predictive value of HIF1α for OS (P = 0.008).Conclusions High HIF1α expression is a predictor of poor clinical response to CRT in HPV-negative LA-HNSCC patients. These patients with high HIF1α significantly benefited with the addition of nimotuzumab to CRT.Clinical trial registration Registered with the Clinical Trial Registry of India (Trial registration identifier—CTRI/2014/09/004980).Subject terms: Tumour biomarkers, Head and neck cancer, Tumour biomarkers, Head and neck cancer, Predictive markers 相似文献
2.
Vinke Jeroen Kaper Hans J. Vissink Arjan Sharma Prashant K. 《Clinical oral investigations》2020,24(11):4019-4030
Clinical Oral Investigations - The aims of this study are to assess different saliva substitutes for their efficacy to lubricate the oral cavity, and to relate this oral lubrication to the ability... 相似文献
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Chandralekha Tampi Prashant Mullerpatan Rajiv Shah Palepu Jagannath Arthur Zimmermann 《Pancreatology》2006,6(3):248-253
Microcystic adenoma or serous cystadenoma is an uncommon tumor and accounts for 1-2% of the exocrine neoplasms of the pancreas. Usually unifocal, they present as single, large, well-demarcated multiloculated cystic tumors, ranging in size from 1 to 25 cm. Multifocal variants or diffuse serous cystadenomas are extremely rare. We present 2 cases of which 1 is a diffuse variant affecting the body, tail and part of the neck of the pancreas. In both the patients the tumors were detected incidentally. We highlight on the diffuse variant in view of its rarity and present a review of literature. In this case the entire body and tail of the pancreas was spongy replaced by multicystic lobules and hyalinized fibrocollagenous stroma. The cysts were lined by low cuboidal glycogen containing bland cells. Such a unique presentation wherein the entire body and tail of the pancreas is replaced with multiple cysts is a diffuse presentation of microcystic adenoma and a search through literature revealed only 7 such cases among the 15 cases with multifocal presentation reported. 相似文献
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Anna P Basu Prashant Kumar Anita M Devlin Christopher J O'Brien 《European journal of paediatric neurology》2007,11(4):240-242
A 15-week old male infant presented with bilateral lower motor neuron facial palsy of unknown cause. Subsequently his growth deteriorated and he developed progressively worsening cough and wheeze. A diagnosis of cystic fibrosis was confirmed and hypovitaminosis A detected. Improvement of the facial palsy was noted following standard management of cystic fibrosis including vitamin A supplementation. 相似文献
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BACKGROUND: Acquired Brown syndrome is known to occur after trauma, iatrogenic events, cysts of superior oblique muscle tendon, and inflammation. The purpose of this study is to report a large series of patients with acquired Brown syndrome secondary to superior oblique muscle cysticercosis and to discuss its management. METHODS: Retrospective analysis was performed of clinical and imaging features, management, and outcome in seven patients with cysticercosis of the superior oblique muscle presenting clinically as Brown syndrome. RESULTS: Seven patients were identified (five male and two female) ranging in age from 6 to 45 years. All patients had the ocular motility limitation, ie, limitation of elevation in adduction., characteristic of Brown syndrome. This was associated with pain and swelling in the superior nasal orbit. Diagnosis was established by observing the cysticercus cyst with scolex on imaging (ultrasound B scan, magnetic resonance imaging, and/or computed tomography). Oral albendazole (15 mg/kg) and oral prednisolone (1mg/kg) were given for 4 weeks, and the patients were followed up for 1 year. Clinical recovery with improvement of ocular motility and regression of imaging features was noted in all patients. CONCLUSIONS: Acquired Brown syndrome secondary to superior oblique muscle cysticercosis is a rare entity. Awareness of this condition, which leads to early diagnosis and institution of prompt medical treatment, results in a successful clinical outcome. 相似文献
9.
K M Shivakumar G M Prashant G S Madhu Shankari V V Subba Reddy G N Chandu 《Indian journal of dental research》2007,18(4):177-180
INTRODUCTION: Bioaerosols are important considerations in infection control as well as in occupational health. Bioaerosols may carry potentially hazardous microbes, viruses, fungi, allergens, and other toxic substances that may harm the dental operator, patient, and the dental assistant by causing nosocomial infections. OBJECTIVE: To assess the level of atmospheric microbial contamination before, during, and after dental treatment procedures in the dental operatory of a mobile dental unit (MDU). MATERIALS AND METHODS: The study included three treatment sessions on different working days, with an interval of one month. The MDU was fumigated before the start of the study. Brain Heart Infusion Agar with 5% sheep blood was used to collect the gravitometric settling of aerosols produced before, during, and after dental treatment procedures. The agar plates were sent for aerobic and anaerobic culture. RESULTS: The results showed that atmospheric microbial contamination (CFUs/plate) was 4 times higher during working sessions as compared to the levels before the working sessions. At the end of the working day, aerosols decreased by almost 3 times that seen during work. CONCLUSION: The aerosols increased during and after work sessions. This shows the increased risk of transmission of infectious agents to the dentists who work in the MDU. Hence, all necessary preventive measures should be advised and need to be followed strictly. 相似文献
10.
Moros EG Novak P Straube WL Kolluri P Yablonskiy DA Myerson RJ 《Physics in medicine and biology》2004,49(6):869-886
The presence of bone in the ultrasound beam path raises concerns, both in diagnostic and therapeutic applications, because significant temperature elevations may be induced at nearby soft tissue-bone interfaces due the facts that ultrasound is (i) highly absorbed in bone and (ii) reflected at soft tissue-bone interfaces in various degrees depending on angle of incidence. Consequently, in ultrasonic thermal therapy, the presence of bone in the ultrasound beam path is considered a major disadvantage and it is usually avoided. However, based on clinical experience and previous theoretical studies, we hypothesized that the presence of bone in superficial unfocused ultrasound hyperthermia can actually be exploited to induce more uniform and enhanced (with respect to the no-bone situation) temperature distributions in superficial target volumes. In particular, we hypothesize that the presence of underlying bone in superficial target volume enhances temperature elevation not only by additional direct power deposition from acoustic reflection, but also from thermal diffusion from the underlying bone. Here we report laboratory results that corroborate previous computational studies and strengthen the above-stated hypothesis. Three different temperature measurement techniques, namely, thermometric (using fibre-optic temperature probes), thermographic (using an infrared camera) and magnetic resonance imaging (using proton resonance frequency shifts), were used in high-power short-exposure, and in low-power extended-exposure, experiments using a 19 mm diameter planar transducer operating at 1.0 and 3.3 MHz (frequencies of clinical relevance). The measurements were performed on three technique-specific phantoms (with and without bone inclusions) and experimental set-ups that resembled possible superficial ultrasound hyperthermia clinical situations. Results from all three techniques were in general agreement and clearly showed that significantly higher heating rates (greater than fourfold) were induced in soft tissue-like phantom materials adjacent (within approximately 5 mm) to a bovine bone as compared to similar experiments without bone inclusions. For low-power long-exposure experiments, where thermal conduction effects are significant, the thermal impact of bone reached at distances > 10 mm from the bone surface (upstream of the bone). Therefore, we hypothesize that underlying bone exposed to planar ultrasound hyperthermia creates a high-temperature thermal boundary at depth that compensates for beam attenuation, thus producing more uniform temperature distribution in the intervening tissue layers. With appropriate technology, this finding may lead to improved thermal doses in superficial treatment sites such as the chest wall and the head/neck. 相似文献