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排序方式: 共有6522条查询结果,搜索用时 15 毫秒
41.
Ashley D. Marumoto MD Srivarshini C. Mohan MD Stephanie A.K. Angarita MD Marissa K. Srour MD Vicky E. Norton Farnaz Dadmanesh MD Armando E. Giuliano MD 《The breast journal》2021,27(11):828-831
For women with breast cancer in whom multiple Oncotype DX® Recurrence Scores (RS) are obtained, RS concordance utilizing current NCCN recommendations has not been evaluated. Patients with two or more RS were identified. RS were stratified by NCCN guidelines and compared for concordance. Twenty-four patients were evaluated. RS concordance varied by tumor type: 100% in the same tumor, 91.7% in multiple ipsilateral tumors, 71.4% in contralateral tumors, and 66.7% in in-breast recurrent tumors. RS concordance for multiple assays in the same patient is not high enough to omit Oncotype DX® testing for each tumor. 相似文献
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PURPOSE: To report a patient with vernal keratoconjunctivitis who developed mycotic keratitis in absence of known risk factors. METHODS: A 17-year-old male suffering from vernal keratoconjunctivitis presented with infective keratitis. The patient had been treated in the past with topical antihistaminics and vasoconstrictors. The patient had not been exposed to topical steroids in 2 years of follow-up. He did not have dry eye or corneal micro or macroerosions prior to the development of infective keratitis. Corneal scrapings were obtained and subjected to KOH wet mount smear, calcofluor and Grams stain as well as bacterial culture sensitivity and fungal culture. RESULTS: Clinical diagnosis of mycotic keratitis in association with vernal conjunctivitis was supported by microbiological investigations. KOH wet mount and calcofluor staining showed presence of filamentous septate hyphae while fungal culture showed growth of aspergillus fumigatus. Antifungal therapy was initiated in the form of topical natamycin 5% suspension to which the patient responded and recovered 6/6 final visual acuity. CONCLUSION: The authors wish to conclude that patients suffering from vernal keratoconjunctivitis, even in the absence of corneal involvement, steroid exposure and trauma, may be at increased risk of developing keratomycosis. 相似文献
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Pramod R. Saxena Carlos M. Villalón K. Mohan Dhasmana Pieter D. Verdouw 《Naunyn-Schmiedeberg's archives of pharmacology》1992,346(6):629-636
Summary Although 5-hydroxytryptamine (5-HT) increases porcine atrial force and rate via 5-HT4 receptors, its effect on left ventricular contractility is not known. Therefore, using the maximum rate of rise of left ventricular pressure (LVdP/dtmax) as an index of cardiac contractility, we have attempted to analyze the possible role of ventricular 5-HT4 receptors in the anaesthetized pig. The full agonists at 5-HT4 receptors, 5-HT and 5-methoxytryptamine (each 3, 10 and 30 g · kg–1), and the -adrenoceptor agonist, isoprenaline (0.01, 0.03 and 0.1 g · kg–1), increased heart rate, LVdP/dtmax and cardiac output. For a given degree of tachycardia, the increase in LVdP/dtmax by isoprenaline was substantially more than that observed with either 5-HT or 5-methoxytryptamine. The 5-HT4 receptor partial agonist, renzapride (3, 10, 30, 100 and 300 g · kg–1), also increased heart rate and LVdP/dtmax dose-dependently. When the heart was paced at 150 beats · min–1, increases in LVdP/dtmax as well as cardiac output (except with the highest doses) by 5-HT, 5-methoxytryptamine and isoprenaline were clearly attenuated. However, the magnitude of attenuation of LVdP/dtmax responses by cardiac pacing was more marked in the case of 5-HT and 5-methoxytryptamine than with isoprenaline.The effects of renzapride (300 g · kg–1) and tropisetron (0.3 and 3 mg · kg–1) on increases in heart rate and LVdP/dtmax by 5-HT, 5-methoxytryptamine and isoprenaline were also studied. In the absence of atrial pacing, both renzapride and tropisetron (3 mg · kg–1) effectively antagonized the responses to 5-HT and 5-methoxytryptamine; except for some decrease in the LVdP/dtmax response by tropisetron, the effect of isoprenaline remained essentially unchanged after the antagonists. During atrial pacing, renzapride significantly antagonized the responses to the first two doses of 5-HT, but the responses to the highest 5-HT dose and to 5-methoxytryptamine remained unaffected. Though, particularly after its higher dose, tropisetron reduced the responses to 5-HT and 5-methoxytryptamine, isoprenaline responses were also affected.The above results show that a significant part of the increase in LVdP/dtmax by 5-HT receptor agonists in the anaesthetized pig is a consequence of tachycardia elicited by these compounds via 5-HT4 receptors. Since the increase in LVdP/dtmax, compared to tachycardia, was much less with 5-HT and 5-methoxytryptamine than with isoprenaline, and since the antagonism by renzapride and tropisetron against 5-HT and 5-methoxytryptamine during atrial pacing was relatively weaker and/or unspecific, it appears unlikely that the increase in LVdP/dtmax, during atria] pacing is mediated by ventricular 5-HT4 receptors. This view is substantiated by our recent in vitro experiments where 5-HT (0.01 to 100 mol/l) failed to significantly increase contractions of porcine left ventricular trabeculae.Correspondence to P. R. Saxena at the above address 相似文献
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The effects of Nd-YAG laser irradiation on platelet function in vitro were studied using platelet rich plasma obtained from the blood of healthy volunteers. Laser delivery was effected via the bare optical fibre, thermal hot tip fibre and spectraprobe and the effects of these probes on platelet function were compared. Fall in platelet count and mean platelet volume (MPV) were proportional to increasing energy delivery with all three probes, the effect being maximal with the spectraprobe, moderate with the hot tip and least with the bare optical fibre. A significant decrease in percentage aggregation of platelets in response to added ADP, collagen and ristocetin with increasing energy delivery was also observed with all three probes. The formation of preformed aggregates, however, showed an increase proportional to energy delivery with all three probes.The differential effects of the various probes used in this study on platelet function may enhance our understanding of the complex role played by platelets in the pathogenesis of complications such as arterial thrombosis and re-occlusion after laser angioplasty. 相似文献
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Mohan Kameshwaran Kiran Natarajan Anand Kumar George Thomas Sathiya Murali 《Indian journal of otolaryngology and head and neck surgery》2003,55(3):196-199
Giant glomus tumors pose a challenge to the Otologist by virtue of their location and vascularity. A vast majority of them
present with tinnitus, conductive hearing loss and cranial nerve palsies. We report the case of a 16-year-old male patient
who presented with sudden right-sided sensorineural hearing loss. This is an unusual presentation of a giant glomus tumor.
We present the clinical features and management of this unusual case. 相似文献
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Method A questionnaire survey of medical officers was conducted to collect data on the most commonly‐presenting diseases and doctors' treatment choices in PHCs in Mysore. Draft guidelines were developed for these conditions based on available literature, together with microbiological sensitivity data from the three district hospitals. User feedback on the draft guidelines and on guidelines in general was obtained from medical officers using a postal questionnaire. Objective To develop standard therapeutic guidelines for selected common diseases for the primary health care centres (PHCs) of a South Indian district and to evaluate medical officers' perceptions about the proposed guidelines and about guidelines in general. Setting Sample of 17 of the 93 PHCs in Mysore. Key findings Upper respiratory tract infection was the most commonly‐presenting condition. Procaine penicillin was the most commonly‐used drug and there were examples of inappropriate treatment choices. The survey produced evidence that access to medicines on the government's “essential” list was not uniform, with many patients having to purchase prescribed drugs that were not on the list. The response rate to the user feedback questionnaire was 62 per cent (31 doctors). The medical officers had positive opinions about guidelines in general and felt that the guidelines we proposed were useful and would help them to improve their prescribing habits. Conclusions Prescribing in primary care in India needs to be improved. The involvement of potential users of the guidelines in their development should increase their acceptability and thus their use in practice. 相似文献
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Development and Application of a Serum C-Telopeptide and Osteocalcin Assay to Measure Bone Turnover in an Ovariectomized Rat Model 总被引:2,自引:0,他引:2
Srivastava AK Bhattacharyya S Castillo G Wergedal J Mohan S Baylink DJ 《Calcified tissue international》2000,66(6):435-442
Biochemical markers applicable to the ovariectomized rat model can provide important tools for studying the bone remodeling
process in this animal model of postmenopausal osteoporosis. We describe the development and application of two biochemical
markers, a C-telopeptide (of type-I collagen) enzyme-linked immunosorbent assay (ELISA) for measuring bone resorption and
an osteocalcin radioimmunoassay (RIA) for measuring bone formation in rat serum. The C-telopeptide ELISA is based on an affinity
purified polyclonal antibody generated against human sequence DFSFLPQPPQEKAHDGGR. The antibody epitope involves amino acid
sequence, which is similar in rat and human carboxyl terminal peptide of type-I (alpha 1) collagen. Sensitivity of the ELISA
was 0.3 ng/ml. The averaged intra- and interassay variation was CV <7%. Averaged dilution and spiked recoveries were 91% and
105%, respectively. The second marker developed is a synthetic peptide-based osteocalcin RIA, which does not require isolation
and purification of intact osteocalcin from rat bone. Osteocalcin antiserum used in the RIA was generated in rabbits against
a synthetic peptide comprising amino acids 33–49 of the rat osteocalcin sequence. The sensitivity of the RIA was 0.15 ng/ml
of peptide. The averaged intra (n = 10) and interassay variations for two controls were CV <9% and 12%, respectively. The
averaged dilution and spiked recoveries were 99.6%. In vivo validation of the C-telopeptide ELISA and osteocalcin RIA was performed in an ovariectomized (OVX) rat model. In 12-week-old
OVX Sprague Dawley rats, the C-telopeptide and osteocalcin concentrations were approximately 65% and 40%, respectively, higher
than the sham group. Estradiol repletion significantly lowered the C-telopeptide and osteocalcin concentration to the levels
of the sham group. In addition, changes in serum C-telopeptide concentration correlated negatively with trabecular BMD measured
by pQCT (r =−0.51, P < 0.001). In conclusion, the C-telopeptide ELISA and osteocalcin RIA exhibited required sensitivity, accuracy, and adequate
discriminatory power to be used for measuring bone resorption and bone formation in the ovariectomized rat model.
Received: 20 August 1999 / Accepted: 5 January 2000 相似文献
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