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31.
Mittal N Zhou Y Ung S Linares C Molloi S Kassab GS 《Annals of biomedical engineering》2005,33(8):1015-1026
A rigorous analysis of blood flow must be based on the branching pattern and vascular geometry of the full vascular circuit
of interest. It is experimentally difficult to reconstruct the entire vascular circuit of any organ because of the enormity
of the vessels. The objective of the present study was to develop a novel method for the reconstruction of the full coronary
vascular tree from partial measurements. Our method includes the use of data on those parts of the tree that are measured
to extrapolate the data on those parts that are missing. Specifically, a two-step approach was employed in the reconstruction
of the entire coronary arterial tree down to the capillary level. Vessels > 40 μm were reconstructed from cast data while
vessels < 40 μm were reconstructed from histological data. The cast data were reconstructed one-bifurcation at a time while
histological data were reconstructed one-sub-tree at a time by “cutting” and “pasting” of data from measured to missing vessels.
The reconstruction algorithm yielded a full arterial tree down to the first capillary bifurcation with 1.9, 2.04 and 1.15
million vessel segments for the right coronary artery (RCA), left anterior descending (LAD) and left circumflex (LCx) trees,
respectively. The node-to-node connectivity along with the diameter and length of every vessel segment was determined. Once
the full tree was reconstructed, we automated the assignment of order numbers, according to the diameter-defined Strahler
system, to every vessel segment in the tree. Consequently, the diameters, lengths, number of vessels, segments-per-element
ratio, connectivity and longitudinal matrices were determined for every order number. The present model establishes a morphological
foundation for future analysis of blood flow in the coronary circulation. 相似文献
32.
Association of koilocytic changes with cervical squamous cell carcinoma is well documented. The studies of such concurrent association may miss those cases of papillomavirus infection where cytomorphologic expression of virus has disappeared by the time carcinoma appears. The authors studied cytologic material before the diagnosis was made of cervical squamous cell carcinoma in situ in 25 patients. Twenty-two (88%) of the 25 patients showed koilocytosis compared with only 6 out of 57 (10.5%) in the control group. The findings of this study support a possible predisposing role of papillomavirus in squamous cell carcinoma of the cervix. 相似文献
33.
Chicks were immunised with different vaccines intramuscularly at the age of eight weeks and challenged twenty one days later with 10 LD50 dose of virulent V intramuscularly. The percentage of absolute survivors were taken as the criterion to assess the potency of the vaccines. To assess the humoral response, sequential levels of antibodies by different tests were assessed before and after vaccination and after challenge.Live vaccines with adjuvants proved to be the best followed by live vaccines. Cross protection could be induced. Assessment of sequential levels of humoral immune response revealed involvement of agglutinins and bactericidal antibodies but such an involvement appears to be not essential for protection. 相似文献
34.
Laura McGillis Nimish Mittal Daniel Santa Mina Joyce So Medha Soowamber Aliza Weinrib Leslie Soever Dmitry Rozenberg Louis Liu Yvonne Tse Joel Katz George S Charames Kieran Murphy Peter Vadas Maxwell P Slepian Scott Walsh Lindsay Wilson Arnon Adler Alyssa Franzese Laura Hussey Dayna‐Lynn Nevay Juan Guzman Hance Clarke 《American journal of medical genetics. Part A》2020,182(3):484-492
The new 2017 diagnostic criteria for hypermobile Ehlers–Danlos Syndrome (hEDS) provide a framework for diagnosing hEDS but are more stringent than the previous Villefranche criteria. Our clinical experience at the GoodHope EDS clinic was that the 2017 criteria left many highly symptomatic patients without a diagnosis of hEDS. We conducted a retrospective cohort study to confirm our clinic experience and assess the accuracy of the 2017 diagnostic criteria for hEDS in patients who had a previous hEDS diagnosis based on the Villefranche criteria. Our study found that 15% (n = 20 of 131) of patients with a prior diagnosis of hEDS met the 2017 diagnostic criteria, and many of the traits used to distinguish hEDS were not significantly more frequent in patients who met 2017 criteria versus those who did not. In both groups objective systemic manifestations were found less frequently than subjective systemic manifestations. Beighton score (BS) as assessed by primary care practitioner was found to be higher than assessment by EDS practitioner in 81% (n = 74 of 91) of cases. Generalized joint hypermobility was confirmed in only 46% (n = 51 of 111) of patients who had a previous diagnosis of hEDS. Higher BS did not correlate with increased number of systemic manifestations in our cohort. Common comorbidities of hEDS were found with similar frequency in those who met 2017 criteria and those who did not. Based on our cohort, the 2017 hEDS diagnostic criteria require refinement to improve its diagnostic accuracy. 相似文献
35.
36.
Evoked potential changes in ischaemic myelopathy 总被引:2,自引:0,他引:2
Kalita J Srivastava AK Mittal P Sharma VP Misra UK 《Electromyography and clinical neurophysiology》2003,43(4):211-215
Somatosensory evoked potentials are employed in the intraoperative monitoring but there is paucity of information about the motor evoked potentials (MEP) in spinal cord ischaemia. Two patients aged 9 and 4 years developed paraplegia following surgery for coarctation of aorta. The aortic cross clamping time in these patients was 100 min and 30 min. respectively. The patient with longer clamping time had flaccid paraplegia and lower limb MEPs were not recordable; whereas the patient with shorter clamping time had spastic paraparesis and prolonged CMCT to right lower limb. The latter patient improved significantly. Tibial SEPs were normal in both the patients. Our results suggest that MEP may have a greater role than SEP in documenting and prognosticating ischaemic myelopathy. 相似文献
37.
Mittal K 《Human pathology》2000,31(9):1179-1180
38.
Closed pyloroduodenal digital dilatation as a complementary drainage procedure to truncal vagotomy 总被引:1,自引:0,他引:1
Out of a total of 300 consecutive cases of duodenal ulcer undergoing surgery, 51 patients were treated by truncal vagotomy and a closed pyloroduodenal digital dilatation. A peroperative assessment of the pyloroduodenal canal was carried out, and in patients with a mobile, supple duodenum showing minimal scarring a standard drainage procedure was not considered necessary. In these patients it was possible to perform a closed pyloroduodenal digital dilatation using the two thumbs to achieve an effective dilatation of 20-30 mm. Post-operative clinical evaluation (Modified Visick grading) and "special" barium meal revealed 86% of patients in Grade I and II at the end of two years (maximum follow-up 3.5 yrs.), with no evidence of lasting gastric stasis. The method is easy, safe and simple. It maintains the anatomical and physiological integrity of the pyloroduodenal ring thereby obviating the hazards of an "incontinent" stomach. Its main limitation appears to be its restricted selectivity and in the present series it could be carried out in about 17% of cases. 相似文献
39.
Galina Sanaksenaho Annika Mutanen Nimish Godbole Maria Hukkinen Laura Merras-Salmio Reetta Kivisaari Antti Kyrönlahti Marjut Pihlajoki Jouko Lohi Markku Heikinheimo Mikko P Pakarinen 《Journal of pediatric surgery》2021,56(5):966-974
BackgroundIntestinal adaptation has been extensively studied experimentally, but very limited data is available on human subjects. In this study we assessed intestinal adaption in humans with short bowel syndrome (SBS).MethodsWe comparatively evaluated mucosal hyperplasia, inflammation, barrier function and nutrient transport using histology, immunohistochemistry and qPCR for selected 52 key genes in duodenal biopsies obtained from children with SBS after weaning off parenteral nutrition (n = 33), and matched controls without intestinal pathology (n = 12). Small bowel dilatation was assessed from contrast small bowel series.ResultsDuodenal mucosa of SBS children showed increased histologic inflammation of lamina propria (p = 0.033) and mucosal mRNA expression of tumor necrosis factor (p = 0.027), transforming growth factor (TGF)-β2 (p = 0.006) and caveolin-1 (CAV1; p = 0.001). Villus height, crypt depth, enterocyte proliferation, apoptosis and expression of proliferation and nutrient transport genes remained unchanged. Pathologic small bowel dilatation reduced crypt depth (p = 0.045) and downregulated mRNA expression of interleukin (IL)-6 by three-fold (p = 0.008), while correlating negatively with IL6 (r = -0.609, p = 0.004). Loss of ileocecal valve (ICV) upregulated mRNA expression of toll-like receptor 4 (TLR4), TGF-β1, CAV1, several apoptosis regulating genes, and mRNA expression of zonulin (p < 0.05 for all).ConclusionsDespite successful adaptation to enteral autonomy, duodenal mucosa of SBS children displayed histologic and molecular signs of abnormal inflammation and regulation of epithelial permeability, whereas no structural or molecular signs of adaptive hyperplasia or enhanced nutrient transport were observed. Excessive dilatation of the remaining small bowel paralleled impaired duodenal crypt homeostasis, while absence of ICV modified regulation of mucosal inflammation, regeneration and permeability.Level of evidenceII 相似文献
40.
Eden-Hybinette Procedure for Revision Surgery in Recurrent Anterior Shoulder Instability in Epilepsy
AimsThe purpose of this study was to analyze the clinical outcomes after Eden-Hybinette procedure for revision surgery in recurrent anterior shoulder instability in patients with epilepsy.Materials and MethodsWe retrospectively evaluated eight such patients between 2015 and 2018. Four patients had failed Latarjet/Bristow procedure and two had failed arthroscopic Bankart procedure, while two had history of both the procedures. After medical control of epilepsy, Eden-Hybinette procedure was performed in all patients. WOSI score and Rowe shoulder score was recorded preoperatively and in subsequent post-operative follow-up. A paired t test was used to analyze and compare preoperative and postoperative outcomes and was considered significant if p value was < 0.05.ResultsThe average follow-up was 30 months (range 24–48 months). There was no recurrence of shoulder instability. The mean WOSI score before surgery was 77.3 (range 70–83), which improved to 24.2 (range 19–30) at 24-month follow-up. The mean Rowe score before surgery was 11.3 (range 5–15), which improved to 81.8(range 65–90) at 24-month follow-up. The improvement in WOSI and Rowe score was found to be statistically significant [p value < 0.05]ConclusionsWe conclude that Eden-Hybinette is a useful revision procedure to manage recurrent anterior shoulder dislocation in patients with epilepsy. Optimum medical control of seizure is also an important factor in preventing recurrent shoulder instability 相似文献