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61.
Ahmed Mohamed Abdel Shafi MBBS BSc Mohammed A. Akhtar MBBS BSc MRCP Alexander Smith MBBS BSc MRCS Martin Yates MD MRCS Aung Y. Oo MD FRCSEd 《Journal of cardiac surgery》2020,35(11):3227-3230
Benign cardiac tumors are rare; they can present with nonspecific symptoms and represent a diagnostic challenge to the clinician. We describe an interesting case of a 26-year-old female who presented with a 6-month history of cough, breathlessness, palpitations, dizziness, and fever. Despite repeated clinical reviews in the community, diagnosis of cardiac tumor was not made until she developed decompensated cardiac failure with bilateral pleural effusions and pulmonary edema. Echocardiogram revealed an enormous left atrial mass that extended one-third into left ventricle during systole. The patient underwent successful surgical resection with histological confirmation of a benign atrial myxoma. 相似文献
62.
Nadeem Siddiqui Md. Jawaid Akhtar M. Shahar Yar Priya Ahuja Waquar Ahsan Sharique Ahmed 《Medicinal chemistry research》2014,23(11):4915-4925
A series of 3-(4-substitutedphenyl)-N-(5-(4-substitutedphenyl-1,3,4-oxadiazol-2-yl)but-2-enamide were synthesized using pharmacophoric elements for in vivo anticonvulsant activity yielding two potent candidates (4d and 4j) in the Phase I and Phase II screening employing maximal electroshock seizure and subcutaneous pentylenetetrazole test having minimal neurotoxicity. Their Phase II screen depicted an increment of nearly 2–10 times for MES and 7–67 folds for scPTZ in the therapeutic index and protective index—the two mainstays in the drug discovery. 相似文献
63.
Javed Akhtar MD Zhou Wang MD Che Yu MD Zhi Ping Zhang MD Ming Ming Bi MD 《Annals of surgical oncology》2014,21(1):315-321
Background
Prognosis of esophageal squamous cell carcinoma (ESCC) is stage-specific; however, some patients with the same stage have different survival outcomes. Clinically, it is significant to explore the biological marker to predict patient’s outcome. We investigated the association between the stathmin1 gene (STMN-1) expression and the prognosis of patients who underwent Ivor-Lewis esophagectomy.Methods
A total of 162 patients who suffered from midthoracic stage IIA ESCC and completely resected with Ivor-Lewis esophagectomy were studied for STMN-1 expression by qRT-PCR in fresh-frozen tissue and validated by immunohistochemistry in matched formalin fixed-paraffin embedded tissue samples. STMN-1 level was evaluated as a prognostic factor in ESCC. SPSS 21.0 software was used to analyze the relationship between STMN-1 expression and clinicopathological characteristics and survival probability.Results
The overall 3- and 5-year survival was 72.20 and 42.00 % respectively. Ninety-four patients (58.02 %) experienced disease recurrence with a disease-free interval of 21.50 ± 1.20 months. qRT-PCR result showed that STMN-1 mRNA level in patients who were alive at the end of follow-up was lower compared with patients who died during the follow-up period (p < 0.05). Immunohistochemical results showed that 94 patients had STMN-1 protein overexpression (58.02 %), patient with STMN-1 overexpression had worse survival compared with patients who had low STMN-1 expression (p = 0.00). Cox regression analysis revealed that STMN-1 protein expression and T classification are independent prognostic factors.Conclusions
Even localized ESCC are potential to relapse with poor prognosis. This study demonstrates that STMN-1 level is an independent prognostic factor after Ivor-Lewis esophagectomy. In addition, assessment of STMN-1 level could improve stratification of stage IIA ESCC patients. 相似文献64.
Addisu Mesfin Lawrence G. Lenke Keith H. Bridwell Usman Akhtar Jennifer M. Jupitz Jeremy L. Fogelson Stuart H. Hershman Han J. Kim Linda A. Koester 《The spine journal》2014,14(12):2819-2825
Background contextThe role of preoperative (preop) narcotic use and its influence on outcomes after spinal deformity surgery are unknown. It is important to determine which patient factors and comorbidities can affect the success of spinal deformity surgery, a challenging surgery with high rates of complications at baseline.PurposeTo evaluate if preop narcotic use persists after spinal deformity surgery and whether the outcomes are adversely affected by preop narcotic use.Study design/settingRetrospective evaluation of prospectively collected data.Patient sampleTwo hundred fifty-three adult patients (230 females/23 males) undergoing primary spinal deformity surgery were enrolled from 2000 to 2009.Outcome measuresPreoperative and postoperative (postop) narcotic use and changes in Oswestry Disability Index (ODI), Scoliosis Research Society (SRS) pain, and SRS total scores.MethodsPreoperative, 2-year postop, and latest follow-up pain medication use were collected along with ODI, SRS pain, and SRS scores. Preoperative insurance status, surgical and hospitalization demographics, and complications were collected. All patients had a minimum 2-year follow-up (average 47.4 months).ResultsOne hundred sixty-eight nonnarcotic (NoNarc) patients were taking no pain meds or only nonsteroidal anti-inflammatories preoperatively. Eighty-five patients were taking mild/moderate/heavy narcotics before surgery. The average age was 48.2 years for the NoNarc group versus 53.6 years for the Narc group (p<.005). There were significantly more patients with degenerative than adult scoliosis in the Narc group (47 vs. 28, p<.001; mild 19 vs. 24, p<.02; moderate 6 vs. 14, p<.0003; heavy 3 vs. 10, p<.0002). Insurance status (private/Medicare/Medicaid) was similar between the groups (p=.39). At latest follow-up, 137/156 (88%) prior NoNarc patients were still not taking narcotics whereas 48/79 (61%) prior narcotic patients were now off narcotics (p<.001). Significant postop improvements were seen in Narc versus NoNarc groups with regard to ODI (26–15 vs. 44–30.3, p<.001), SRS pain (3.36–3.9 vs. 2.3–3.38, p<.001), and overall SRS outcome (3.36–4 vs. 2.78–3.68, p<.001) scores. A comparison of change in outcome scores between the two groups showed a higher improvement in SRS pain scores for the Narc versus NoNarc group (p<.001).ConclusionsIn adults with degenerative scoliosis taking narcotics a significant decrease in pain medication use was noted after surgery. All outcome scores significantly improved postop in both groups. However, the Narc group had significantly greater improvements in SRS pain scores versus the NoNarc group. 相似文献
65.
Mohammad Nishat Akhtar Muneer Khan Sher Afghan Khan Asif Afzal Ram Subbiah Sheikh Nazir Ahmad Murtuja Husain Mohammad Mursaleen Butt Abdul Rahim Othman Elmi Abu Bakar 《Materials》2021,14(10)
In the present investigation, the non-recrystallization temperature (TNR) of niobium-microalloyed steel is determined to plan rolling schedules for obtaining the desired properties of steel. The value of TNR is based on both alloying elements and deformation parameters. In the literature, TNR equations have been developed and utilized. However, each equation has certain limitations which constrain its applicability. This study was completed using laboratory-grade low-carbon Nb-microalloyed steels designed to meet the API X-70 specification. Nb- microalloyed steel is processed by the melting and casting process, and the composition is found by optical emission spectroscopy (OES). Multiple-hit deformation tests were carried out on a Gleeble® 3500 system in the standard pocket-jaw configuration to determine TNR. Cuboidal specimens (10 (L) × 20 (W) × 20 (T) mm3) were taken for compression test (multiple-hit deformation tests) in gleeble. Microstructure evolutions were carried out by using OM (optical microscopy) and SEM (scanning electron microscopy). The value of TNR determined for 0.1 wt.% niobium bearing microalloyed steel is ~ 951 °C. Nb- microalloyed steel rolled at TNR produce partially recrystallized grain with ferrite nucleation. Hence, to verify the TNR value, a rolling process is applied with the finishing rolling temperature near TNR (~951 °C). The microstructure is also revealed in the pancake shape, which confirms TNR. 相似文献
66.
67.
The sponge/Matrigel angiogenesis assay 总被引:11,自引:0,他引:11
It has become increasingly clear that definitive tests for angiogenesis require in vivo assays. Recently, the Matrigel plug assay has become the method of choice for many studies involving in vivo testing for angiogenesis. In this assay, test angiogenesis-inducing compounds such as bFGF or tumor cells are introduced into cold liquid Matrigel which, after subcutaneous injection, solidifies and permits penetration by host cells and the formation of new blood vessels. Assessment of angiogenesis in the Matrigel plug is achieved either by measuring hemoglobin or by scoring selected regions of histological sections for vascular density. We now describe a modification of the Matrigel plug assay which permits a more precise visualization of the angiogenic reaction, provides directional information, requires no histological analysis, and lends itself to photographic documentation and image analysis protocols. We illustrate the assay by describing dose- and time-dependent responses to tumors of murine and human origin, to angiogenesis-inducing factors such as bFGF (FGF-2) and VEGF and to anti-angiogenic agents such as endostatin. The method has been used as well to demonstrate blood vessel recruitment by embryonic chick aortic arch rudiments. Additionally it has been able to detect strain-dependent differences in susceptibility to angiogenic stimulation. 相似文献
68.
Saad Akhtar Khan Hussain Shallwani Muhammad Shahzad Shamim Ghulam Murtaza Syed Ather Enam Reema Obaid Qureshi Muhammad Zubair Tahir 《Child's nervous system》2014,30(2):277-281
Objective
This study aimed to determine the risk factors associated with poor outcome of decompressive craniectomy (DC) for severe traumatic brain injury (TBI) in pediatric patients.Methods
This retrospective study is conducted on pediatric population (age 1–15 years) presenting with TBI who underwent DC at our institute between January 2000 and 2010. Based on Glasgow outcome score (GOS) at a minimum follow-up of 5 months, patients were divided into two groups, namely poor outcome (GOS 1, 2, and 3) and good outcome (GOS 4 and 5). Records were reviewed and analyzed for preoperative and intraoperative predictors.Results
We found 25 patients who were eligible as per selection criteria. Mean age at presentation was 6?±?4 years and there was male preponderance (84 %). Fall (60 %) was the most common mechanism of injury followed by gunshots and road traffic accident. On univariate analysis, presenting GCS ≤5 (p value?=?0.009), delay in presentation of more than 150 min (p value?=?0.010), DC performed after more than 4 h of arrival in hospital (p value?=?0.042), and intraoperative blood loss exceeding 300 ml (p value?=?0.001) were significant predictors of poor outcome.Conclusion
Our study suggests that DC in children is not only a life-saving procedure, but also leads to a good functional outcome after severe injury. However, patient selection still remains an important aspect, and the above-mentioned factors should be considered while deciding for DC to improve survival. Further prospective studies on larger sample size are warranted to validate our results. 相似文献69.
Md. Sohaib Akhtar Arshad Hafeez Khan Mohammed Fahud Khurram Imran Ahmad 《Indian Journal of Plastic Surgery》2014,47(2):221-226
Background:
Soft-tissue defects around the knees are common in injured limbs and in the same injury the leg is often involved and the thigh is spared. Furthermore due to pliable and relatively lax skin, we have used inferiorly based thigh flap to reconstruct defects around knee joint.Aims and Objectives:
The aim of this study is to evaluate the use of inferiorly based thigh flap to cover soft-tissue defects over the proximal one-third of the leg, patellar region, knee, and lower thigh.Materials and Methods:
This study was conducted during the period between October 2011 and February 2013. Inferiorly based anteromedial thigh fasciocutaneous flap was performed on 12 patients and inferiorly based anterolateral thigh fasciocutaneous flap on four patients. The sites of the soft-tissue defects included patellar regions, infrapatellar region, upper one-third of leg, lower thigh, and over the knee joint.Results:
Patients were evaluated post-operatively in terms of viability of flap, the matching of the flap with the recipient site, and donor site morbidity. All the flaps survived well except one which developed distal marginal flap loss, one in which wound dehiscence was noticed, and two in which mild venous congestion was observed. Venous congestion in two patients subsided on its own within 3 days. One patient with wound dehiscence achieved complete healing by secondary intention. Patient who developed distal flap loss required debridement and skin grafting. No appreciable donor site morbidity was encountered. Skin colour and texture of the flap matched well with the recipient site.Conclusions:
The inferiorly based thigh flap is a reliable flap to cover the defect over proximal one-third of the leg, patellar region, knee, and lower thigh.KEY WORDS: Defect around the knee joint, inferiorly based thigh flap, perforator based flap 相似文献70.
Md Sohaib Akhtar M. Fahud Khurram Rampukar Choudhary A.H. Khan Imran Ahmad 《European journal of plastic surgery》2014,37(10):547-554