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111.
Fine needle aspiration cytology (FNAC) enjoys popularity among clinicians worldwide, as a first line of investigation in all patients with lymphadenopathy and is preferred over biopsy because of its minimally invasive nature and cost-effectiveness. Although non-Hodgkin's lymphomas (NHL) are conventionally diagnosed and graded on biopsy specimens, it may be useful to be able to not only diagnose but also grade these cases on FNAC smears. The WHO and REAL classifications forming the basis of treatment in some centres rely on clinical features, immunocytochemistry and cytogenetics, which are beyond reach of most centres in the developing countries. This study therefore is aimed at diagnosing and grading NHLs on morphological parameters. The cytologic grading accuracy is compared with the histologic grades assigned according to the International Working Formulation (IWF) system which relies solely on morphological features, most important of which is cell size. Ninety five cases were retrieved over a 3 year period (May 2000 to April 2003). These were (i) cases where a cytological diagnosis of NHL or suspicious of NHL was made and corresponding histological sections available and (ii) cases where a diagnosis of NHL was made in histology and corresponding FNAC smears were available irrespective of the cytological diagnosis. The diagnostic accuracy of FNAC for NHLs was determined using histology as the gold standard. Cases were also graded on FNAC smears using a three tier grading system based upon cell size into low, intermediate and high grades. Cytologically assigned grades were correlated with the corresponding histological grades (IWF) to determine grading accuracy. An accurate diagnosis of NHL was thus possible in 67/95 (70.5%) cases. Overall accurate grading was seen in 65/95 (68%) cases using cytological criteria. Accurate cytologic grading was possible in 14/15 (93.33%) low grade, 11/18 (61.11%) intermediate and 40/62 (64.5%) high grade non Hodgkin's lymphomas. Kappa statistics revealed a very good agreement between cytological and histological grades for low grade NHL. The kappa scores for intermediate and high grade NHLs indicated moderate agreement. Using the two-tier system grading the kappa value for high grade lymphomas improved to 0.72, indicating good concordance. This study highlights the utility of FNAC as a morphological tool for diagnosing and grading NHLs in a significant number of cases. This modality may assist clinicians in management of cases of NHLs, especially in centres working within the constraints of limited availability or non availability of ancillary techniques.  相似文献   
112.
Convective delivery of nutrients is important to enhance mass transport within tissue engineered (TE) products. Depending on the target tissue, an ideal TE product will have an integrated microvasculature that will eliminate mass transport limitations that can occur during product growth in vitro and integration in vivo. A synthetic approach to develop microvasculature involves development of network designs with efficient mass transfer characteristics. In this paper, utilizing a planar bifurcating network as a basis, we develop an approach to design optimal flow networks that have maximum mass transport efficiency for a given pressure drop. We formulated the optimization problem for a TE skin product, incorporating two types of duct flow, rectangular and square, and solved using a generalized reduced gradient algorithm. Under the conditions of this study, we found that rectangular ducts have superior mass transport characteristics than square ducts. Microvascular area per volume values obtained in this work are significantly greater than those reported in the literature. We discuss the effect of network variables such as porosity and generations on the optimal designs. This research forms the engineering basis for the rational development of TE products with built-in microvasculature and will pave the way to design complex flow networks with optimal mass transfer characteristics.  相似文献   
113.
A series of 2‐oxo‐2‐phenylethylidene linked 2‐oxo‐benzo[1,4]oxazine analogues 17a–x and 18a–o , incorporated with a variety of electron‐withdrawing as well as electron‐donating groups at ring A and ring C, were synthesized under greener conditions in excellent yields (up to 98%). These analogues 17a–x and 18a–o were evaluated for their arachidonic acid (AA)‐induced platelet aggregation inhibitory activities in comparison with the standard reference aspirin (IC50 = 21.34 ± 1.09 µg/mL). Among all the screened compounds, eight analogues, 17i , 17x , 18f , 18g , 18h , 18i , 18l , and 18o , were identified as promising platelet aggregation inhibitors as compared to aspirin. In addition, cytotoxic studies in 3T3 fibroblast cell lines by MTT assay of the promising compounds ( 17i , 17x , 18f–18i , 18l , and 18o ) were also performed and the compounds were found to be non‐toxic in nature. Furthermore, the results on the AA‐induced platelet aggregation inhibitory activities of these compounds ( 17i , 17x , 18f–18i , 18l , and 18o ) were validated via in silico molecular docking simulation studies. To the best of our knowledge, this is the first report of the identification of non‐peptide‐based functionalized 2‐oxo‐benzo[1,4]oxazines as platelet aggregation inhibitors.
  相似文献   
114.
Neurosurgical Review - Cavernous sinus haemangiomas (CSHs) are rare malformations of the microcirculation arising from the cavernous sinus. A systematic review and pooled data analysis of the...  相似文献   
115.
Living organ donors face direct costs when donating an organ, including transportation, lodging, meals, and lost wages. For those most in need, the National Living Donor Assistance Center (NLDAC) provides reimbursement to defray travel and subsistence costs associated with living donor evaluation, surgery, and follow‐up. While this program currently supports 9% of all US living donors, there is tremendous variability in its utilization across US transplant centers, which may limit patient access to living donor transplantation. Based on feedback from the transplant community, NLDAC convened a Best Practices Workshop on August 2, 2018, in Arlington, VA, to identify strategies to optimize transplant program utilization of this valuable resource. Attendees included team members from transplant centers that are high NLDAC users; the NLDAC program team; and Advisory Group members. After a robust review of NLDAC data and engagement in group discussions, the workgroup identified concrete best practices for administrative and transplant center leadership involvement; for individuals filing NLDAC applications at transplant centers; and to improve patient education about potential financial barriers to living organ donation. Multiple opportunities were identified for intervention to increase transplant programs’ NLDAC utilization and reduce financial burdens inhibiting expansion of living donor transplantation in the United States.  相似文献   
116.
Lower limb crush injury is a major source of mortality and morbidity in trauma patients. Complications, especially surgical site infections (SSIs) are a major source of financial burden to the institute and to the patient as it delays rehabilitation. As such, every possible attempt should be made to reduce any complications. We, thus, aimed to compare the outcomes in early vs delayed closure of lower extremity stumps in cases of lower limb crush injury requiring amputation, so as to achieve best possible outcome. A randomised controlled study was conducted in the Division of Trauma Surgery & Critical Care at Jai Prakash Narayan Apex Trauma Centre, All India Institute of Medical Sciences, New Delhi from 1 September 2018 to 30 June 2019 and included patients undergoing lower limb amputation below hip joint. Patients were randomised in two groups, in one group amputation stump was closed primarily, while in the second group delayed primary closure of stump was performed. We compared rate of SSI, length of hospital stay, and number of surgeries in both the groups. Fifty‐six patients with 63 amputation stumps were recruited in the study. Mean age of patients in the study was 34 years, of which about 95% patients were males. The most common mechanism of injury was road traffic injury in 66% of patients. Mean injury severity score was 12.28 and four patients had diabetes preoperatively. Total 63 extremities were randomised with 30 cases in group I and 33 cases in group II as per computer‐generated random number. Above knee amputations was commonest (57.14%) followed by below knee amputations (33.3%). Two patients died in the current study. In group I, In‐hospital infection was detected in 7 cases (23.3%) and in group II 9 cases (27.3%) had SSI during hospital admission (P > .05). Mean hospital stay in group I was 10.32 ± 7.68 days and in group II was 11 ± 8.17 days (P > .05). Road traffic injuries and train‐associated injuries are a major cause of lower limb crush injuries, leading to limb loss. Delayed primary closure of such wounds requires extra number of surgical interventions than primary closure. There is no difference in extra number of surgical interventions required in both the groups. Thus, primary closure can be safely performed in patients undergoing lower limb amputations following trauma, provided that a good lavage and wound debridement is performed.  相似文献   
117.
118.
Acute injuries or wound is required the fast delivery of drug to control infections without any side effect. In this direction in the present investigation, antibiotic ciprofloxacin loaded hydrophilic biodegradable poly vinyl alcohol (PVA) and sodium alginate (NaAlg) electrospun composite nanofiber based transdermal patch was developed for local delivery of antibiotic drug. The antibiotic drug ciprofloxacin was loaded in it by active loading. The drug entrapped in the composite nanofibers was confirmed by the scanning electron microscopy and swelling behavior. The in vivo studies were carried on male rabbits by using the drug loaded and unloaded composite nanofibers transdermal patch and marketed one. It is observed that, in vitro activity provides a sustained and controlled release pattern of the drug from transdermal patch. The mechanism of drug release was also studied using different models. The nanofiber transdermal patch follows the Higuchi and Korsmeyer–Peppas model for drug release. The in vivo studies demonstrate that, wound healing takes place in less time as compared drug unloaded patch. Hydroxyproline produced in wound bed with time shows that it content is maximum in case drug loaded PAV-NaAlg patch. This demonstrates that wound healing rate is higher in case drug loaded PVA-NaAlg transdermal patch.  相似文献   
119.
In a randomized, controlled trial, ten patients with pulmonary heart disease due to severe chronic airflow obstruction were stratified into two groups: group 1 had clinical features of congestive heart failure during respiratory failure and were regularly receiving diuretics; group 2 had no such clinical features and were not receiving diuretics. In group 1, when placebo was substituted for diuretics, pulmonary edema developed in three patients; exercise performance and ventricular function of the remaining two patients deteriorated. In group 2, there was no difference in exercise tolerance or ventricular function between placebo and diuretic therapy. The clinical deterioration in group 1 was related to abnormal left ventricular function. Thus, diuretics benefit only patients who have clinical features of congestive heart failure. In patients with isolated abnormal right ventricular function, diuretics may be harmful.  相似文献   
120.
Background: Exercise‐induced ventricular arrhythmias (EIVA) are frequently observed during exercise testing. However, the clinical guidelines do not specify their significance and so we examined this issue in our population. Methods: A retrospective analysis of prospectively collected data was performed on 5754 consecutive male veterans referred for exercise testing at two university‐affiliated Veterans Affairs Medical Centers. Exercise test responses were recorded and cardiovascular mortality was assessed after a mean follow‐up of 6 ± 4 years. EIVA were defined as frequent premature ventricular complexes (PVCs) constituting more than 10% of all ventricular depolarizations during any 30‐second ECG recording, or a run of three or more consecutive PVCs during the exercise test or recovery. Results: EIVA occurred in 426 patients (7.4%). There were 550 (10.6%) cardiovascular deaths during follow‐up. Seventy two (17%) patients with EIVA died of cardiovascular causes, whereas 478 (9.0%) of patients without EIVA died of cardiovascular causes (P < 0.001). Patients with EIVA had a higher prevalence of cardiovascular disease, resting PVCs, resting ST depression, and ischemia during exercise than patients without EIVA. In a Cox hazards model adjusted for age, cardiovascular disease, exercise‐induced ischemia, ECG abnormalities, exercise capacity and risk factors, EIVA was significantly associated with time to cardiovascular death. The combination of both resting PVCs and EIVA was associated with the highest hazard ratio. Conclusions: EIVA are independent predictors of cardiovascular mortality after adjusting for other clinical and exercise test variables; combination with resting PVCs carries the highest risk.  相似文献   
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