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61.
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Antaki F Tringali A Deprez P Kwan V Costamagna G Le Moine O Delhaye M Cremer M Devière J 《Gastrointestinal endoscopy》2008,67(1):163-168
BACKGROUND: Duodenal duplication cysts are rare congenital anomalies. Symptomatic cases have classically been treated by surgical resection, which can be complex because of the close proximity of the cysts to the papilla. OBJECTIVE: To describe a series of 8 patients with symptomatic duodenal duplication cysts who were treated endoscopically, with a special focus on the long-term outcome. DESIGN: Retrospective case series. SETTING: Three tertiary-care European academic hospitals. PATIENTS: Eight patients, age 8 to 72 years, were treated endoscopically for symptomatic intraluminal duodenal duplication cysts between 1981 and 2006. Seven patients presented with acute pancreatitis, and one patient presented with jaundice. INTERVENTION: Endoscopic incision and marsupialization of the cysts was performed by using a variety of endoscopic tools (needle-knife and regular sphincterotomes, cystotomes, and polypectomy snares). MAIN OUTCOME MEASUREMENTS: Technical success of endoscopic intervention and long-term clinical recurrence of symptoms. RESULTS: No major complications occurred. All patients remained asymptomatic at a median follow-up of 7.3 years. LIMITATIONS: Retrospective study; the small number of patients. CONCLUSIONS: The endoscopic treatment of symptomatic intraluminal duodenal duplication cysts is a safe and effective technique, with excellent long-term results. It represents a minimally invasive alternative to surgical resection and might be considered the preferred therapeutic modality for these cases. 相似文献
63.
J. Brendan Foley Kumar Sridhar John Dawdy Chris Konstantinou Robert I. G. Brown Ian M. Penn 《Catheterization and cardiovascular interventions》1994,31(4):264-269
Prolonged inflation with perfusion balloons is commonly used in failed angioplasty. The objective of this study was to determine the angiographic outcome of 59 consecutive patients treated with prolonged inflation with perfusion balloons as the primary treatment for failed angioplasty. Angiographic success (< 50% stenosis and normal flow) was achieved in 41%. Angiographic success was greater in the left anterior descending coronary artery (67% versus 33% for non-left anterior descending involvement, P = .044) and was less in complex dissections (25% versus 75% for no dissection or simple dissections, P = .025). Angiographic deterioration occurred in 37.5% of the successful group and 77% of the unsuccessful group (P = .002) and was more frequent in the right coronary artery (88% versus 50% for non-right coronary involvement, P = .007) and complex dissections (92% versus 38% for no dissection or simple dissections, P = .0001). Thus, in a group of patients with unsuccessful outcome following conventional balloon angioplasty, success with the perfusion balloon was modest. Furthermore, angiographic deterioration was frequently observed following unsuccessful prolonged inflation. 相似文献
64.
Emergence of multidrug-resistant TB (MDR-TB) and extensively drug-resistant TB over the past decade presents an unprecedented public health challenge to which countries of concern are responding far too slowly. Global Tuberculosis Report 2014 marks the 20th anniversary of the Global Project on Anti-Tuberculosis Drug Resistance Surveillance, indicating the highest global level of drug-resistance ever recorded detection of 97?000 patients with MDR-TB resulting in 170?000 deaths in 2013. Treatment of MDR-TB is expensive, complex, prolonged (18–24 months) and associated with a higher incidence of adverse events. In this context, nanocarrier delivery systems (NDSs) efficiently encapsulating considerable amounts of second-line anti tubercular drugs (sATDs), eliciting controlled, sustained and more profound effect to trounce the need to administer sATDs at high and frequent doses, would assist in improving patient compliance and avoid hepatotoxicity and/or nephrotoxicity/ocular toxicity/ototoxicity associated with the prevalent sATDs. Besides, NDSs are also known to inhibit the P-glycoprotein efflux, reduce metabolism by gut cytochrome P-450 enzymes and circumnavigate the hepatic first-pass effect, facilitating absorption of drugs via intestinal lymphatic pathways. This review first provides a holistic account on MDR-TB and discusses the molecular basis of Mycobacterium tuberculosis resistance to anti-tubercular drugs. It also provides an updated bird’s eye view on current treatment strategies and laboratory diagnostic test for MDR-TB. Furthermore, a relatively pithy view on patent studies on second-line chemotherapy using NDSs will be discussed. 相似文献
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Subhakar Kandi Tilak Kumar K Shravika Reddy Kandi Neeta Mathur Challa Devi D Rajesham Adepu 《The Indian journal of tuberculosis》2021,68(3):379-383
BackgroundTreatment outcomes for Multidrug-Resistant Tuberculosis (MDR TB) is generally poor. The study aims to know about the treatment outcomes of MDR-TB under programmatic conditions in Hyderabad District and to analyze the factors influencing the treatment outcomes.MethodsThis is a retrospective study in which 377 patients of Hyderabad district, Telangana state who were diagnosed with MDR TB and registered at Drug Resistance TB Treatment site of Government General & Chest Hospital, Hyderabad from 4th quarter 2008 to 4th quarter 2013 were included in the study. Impact of Demographic factors (age, sex; Nutritional status (BMI); Co-morbid condition (Diabetes, HIV, Hypothyroidism); Programmatic factors (time delay in the initiation of treatment); Initial Resistance pattern on the outcomes were studied and analyzed.ResultsThe treatment outcomes of Multidrug-Resistant Tuberculosis under Programmatic Conditions were: 57% cured, 21.8% died, 19.6% defaulted, 1.1% failed and 0.5% switched to XDR. Age, Sex, BMI had a statistically significant impact on treatment outcomes. Hypothyroidism and Delay in the initiation of treatment >1 a month had an impact on the outcomes though not statistically significant. NO impact on treatment outcomes was found when Rifampicin resistance & INH sensitive patients were compared with those resistant to both INH and Rifampicin.ConclusionTo reduce MDR-TB transmission in the community, improvement of treatment outcomes, via ensuring adherence, paying special attention to elderly patients is required. The Programmatic Management of Drug Resistance Tuberculosis (PMDT) should seriously think of providing Nutritional support to patients with low BMI to improve outcomes. In the programmatic conditions if we could address the problems like delay in initiation of treatment and proper management of comorbidities like HIV, Diabetes, Hypothyroidism would definitely improve the treatment outcomes. 相似文献
67.
Jeffrey D. Hirsch Eliot L. Siegel Sridhar Balasubramanian Kenneth C. Wang 《Journal of digital imaging》2015,28(4):407-411
The Digital Imaging and Communications in Medicine (DICOM) standard is the universal format for interoperability in medical imaging. In addition to imaging data, DICOM has evolved to support a wide range of imaging metadata including contrast administration data that is readily available from many modern contrast injectors. Contrast agent, route of administration, start and stop time, volume, flow rate, and duration can be recorded using DICOM attributes [1]. While this information is sparsely and inconsistently recorded in routine clinical practice, it could potentially be of significant diagnostic value. This work will describe parameters recorded by automatic contrast injectors, summarize the DICOM mechanisms available for tracking contrast injection data, and discuss the role of such data in clinical radiology. 相似文献
68.
Sridhar Ravi Tim Siesenop Olivier Bertrand Liang Li Charlotte Doussot William H. Warren Stacey A. Combes Martin Egelhaaf 《Proceedings of the National Academy of Sciences of the United States of America》2020,117(49):31494
Animals that move through complex habitats must frequently contend with obstacles in their path. Humans and other highly cognitive vertebrates avoid collisions by perceiving the relationship between the layout of their surroundings and the properties of their own body profile and action capacity. It is unknown whether insects, which have much smaller brains, possess such abilities. We used bumblebees, which vary widely in body size and regularly forage in dense vegetation, to investigate whether flying insects consider their own size when interacting with their surroundings. Bumblebees trained to fly in a tunnel were sporadically presented with an obstructing wall containing a gap that varied in width. Bees successfully flew through narrow gaps, even those that were much smaller than their wingspans, by first performing lateral scanning (side-to-side flights) to visually assess the aperture. Bees then reoriented their in-flight posture (i.e., yaw or heading angle) while passing through, minimizing their projected frontal width and mitigating collisions; in extreme cases, bees flew entirely sideways through the gap. Both the time that bees spent scanning during their approach and the extent to which they reoriented themselves to pass through the gap were determined not by the absolute size of the gap, but by the size of the gap relative to each bee’s own wingspan. Our findings suggest that, similar to humans and other vertebrates, flying bumblebees perceive the affordance of their surroundings relative their body size and form to navigate safely through complex environments.Avoiding collisions with obstacles is a requirement for successful locomotion through most natural habitats, where the physical environment is often cluttered and complex. At the most elemental level, animals moving through their environments need to identify gaps between obstacles and assess their passability. In this context, whether a gap between obstacles “affords” passing is determined by the fit between the spatial layout of the environment and the properties of the organism’s form and action system, as described in classical theses on affordances (1–3). In humans and other highly cognitive vertebrates, the perception of affordances for performing visually guided actions such as grasping, passing through apertures, and climbing is actively shaped throughout ontogeny, as body size, configuration, and experience change (2, 4–7). However, the strategies used by animals with much smaller brains, such as insects, to contend with the challenges of navigating environmental clutter and spatial heterogeneity are unclear.We used bumblebees to investigate whether flying insects take into account their own size during interactions with their surroundings. Bumblebees and other volant insects that travel long distances (8) and frequently encounter regions of dense clutter can be expected to exhibit strategies to avoid collisions, because damage to sensitive structures such as the wings is irreparable and adversely impacts flight performance and lifespan (9, 10). For an animal attempting to navigate through tight spaces, perceiving the relationship between the layout of the environment and its own size can help inform the animal of its potential for collision-free passage. Bumblebee workers naturally display large variation in body size within a given colony (11, 12), and thus are particularly suitable models for testing the effects of insect body size on aerial navigation and for determining whether insects perceive the external environment in relation to their own spatial dimensions.To elicit repeatable flight behavior, we trained foraging bumblebees to fly within a 1.6 × 0.3 × 0.3 m (l × w × h) flight tunnel that separated the hive from a foraging arena (Materials and Methods, SI Appendix, Fig. S1, and Movie S1). After bees were habituated to the setup and began foraging normally, we placed an unexpected obstacle within the tunnel, consisting of a thin vertical wall (5-mm thickness) spanning the tunnel’s width and height. The obstructing wall contained a rectangular gap starting midway up and extending to the top of the wall (Materials and Methods, SI Appendix, Fig. S1, and Movie S1). The width of the gap was varied between 20 and 60 mm over different trials, with the presenting order of gap sizes chosen randomly. A high-speed camera placed above the tunnel was used to record bees’ instantaneous positions, heading/yaw orientations (Fig. 1A), and trajectories as they approached the obstructing wall and passed through the gap. To prevent bees from becoming familiar with the experimental paradigm, the obstructing wall was removed after each flight recording. In total, we recorded and analyzed over 400 flights of bees of varying body sizes flying through seven different gap sizes (SI Appendix, Table S1). For the population of bees recorded, wingspan was the longest dimension of the body and it varied linearly by a factor of 1.9 compared to their longitudinal body length while in flight (SI Appendix, Fig. S2A).Open in a separate windowFig. 1.Bumblebees can safely fly through gaps that are smaller than their wingspan. (A and B) Illustrations indicating the wingspan of bees (Ws), the size of the gap (Gs), and the positive and negative yaw (heading) angles for bees flying in the tunnel, respectively. (C) Schematic illustration of the flight of a bee flying through a gap that is much wider than its wingspan. (D) The instantaneous yaw angle of bee shown in C. (E) Schematic illustrationof the flightofabeeflying through a gap that is smaller than its wingspan. (F) The instantaneous yaw angle of bee shown in E. Flights, in both cases (C and E), consisted of approach, lateral peering, and—for the smaller gap size (E)—body reorientation (an increase in yaw angle) while passing through the gap. The differences in reorientation behavior can be noted at x = 0 (location of the gap), whereas in F the bee displays a large increase in yaw angle that reorients its body to pass through the small gap, and body reorientation in D is minimal. For the flight shown in C and D, Ws = 27.5 mm and Gs = 50 mm, while for the flight shown in E and F, Ws = 27 mm and Gs = 25 mm. 相似文献
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70.
Swetlana Gautam Priyanka Singh Manjari Singh Subhadeep Roy Jitendra K. Rawat Rajnish K. Yadav Uma Devi Pushpraj S. Gupta Shubhini A. Saraf Gaurav Kaithwas 《RSC advances》2018,8(7):3512
The present study was proposed to investigate the effect of rifaximin (RFX) on methyl nitrosourea (MNU) induced mammary gland carcinoma in albino wistar rats. Animals were randomized and divided among four groups of six animals each. Group I (control 0.9% normal saline, 3 ml kg−1, p.o.); Group II (toxic control, MNU 47 mg kg−1, i.v.); Group III (RFX, 25 mg kg−1, p.o.); Group IV (RFX, 50 mg kg−1, p.o.). Toxicity was induced by single i.v. injection of MNU. MNU treatment was evident with increased alveolar bud count, differentiation score, up-regulated inflammatory enzyme markers (COX, LOX, NO and H2S) and oxidative stress markers (TBAR''s, protein carbonyl, SOD, catalase and Ach). The mammary gland surface architecture was studied using SEM, carmine staining and H&E staining. The treatment with RFX elicited noticeable restoration of the overall histological architecture in the experimental animals similar to the control. In the MNU treated toxic group, the levels of oxidative stress markers significantly increased in comparison to the control, which was subsequently restored after RFX treatment. Furthermore, RFX up regulated the levels of caspase 3 and caspase 8, when compared to the MNU treated animals. MNU associated toxicity was also ascertained, when determined for UCHL-1, COX, NF-κBp65, BAD, and BCL-xl expression, while RFX demonstrated modulation of the same.The present study was proposed to investigate the effect of rifaximin (RFX) on methyl nitrosourea (MNU) induced mammary gland carcinoma in albino wistar rats. 相似文献