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41.
Micro vascular free tissue transfer scores over the traditional myocutaneous flaps by providing better cosmesis and function. However, the increased operating tine and costs and the necessity for two operating teams sometimes, negate these advantages and even where this facility is freely available, myoentancous flaps continue to be widely used. To determine the ideal choice of reconstruction in patients after oral resection, we compared our experience with these two methods of reconstruction. Since 1997, when we first started micro vascular reconstruction, 17 patients have undergone this procedure for oral reconstruction. During this same period, 40 patients had pectoralis major myocutaneous flap reconstruction of the oral cavity. These two groups are compared with regard to cosmetic and functional results (as measured by patient’s level of satisfaction) operating time, duration of hospitalization, cost and complications. Results: Eightv seven percent of the patients in the micro vascular group and 75% in the myocutaneous group were satisfied with the cosmetic and functional results. In the microvascular group, average operating time was increased by 4 hours; hospitalization by 3 days and average cost of treatment was doubled. Flap failures and re-explorations were significantly higher in the micro vascular group. Based on these results, we would like to suggest the ideal method of reconstruction of the oral cavity in specific subgroups of patients in a corporate hospital setting.  相似文献   
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Aim: The purpose of this study was to assess objectively the ultrastructure of the secretory granules in rabbit conjunctival mucin‐producing ‘goblet’ cells. Method: The upper eyelids from five young adult dioestrous female rabbits were dissected out, stretched onto a cardboard support and prepared for transmission electron microscopy by repeated application of an isotonic two per cent glutaraldehyde fixative at room temperature. Post‐fixation treatment included osmium tetroxide and staining with uranyl acetate and lead citrate. Low magnification micrographs were taken of the goblet cells of the conjunctiva, printed at a magnification of approximately 6,000 and the number, size and features of the secretory granules assessed. Results: Across the entire palpebral conjunctiva of ail five rabbits, the majority of mucous cells displayed a goblet shape and the secretory granules were uniformly pale in staining. The average width of the goblet cells was 10.8 ± 1.1 μm and the diameter of the secretory granules was 0.82 ± 0.16 μm. However, in localised regions across the palpebral conjunctiva of two of the rabbits, some goblet cells were different in that the secretory granules had either a denser‐staining core, in which some of the granules were densely staining (while others were pale) or most of the granules were densely staining. These mucous cells had an average diameter of 10.3 ± 1.7 μm and the granule diameters averaged 0.88 ± 0.01 μm. For these abnormal goblet cells, inflammatory cells were found in their immediate vicinity. Occasionally, goblet cells were seen to be in the process of degranulation with associated apparent cell necrosis and the mucin granule diameter was close to 1 μm. Conclusions: The ultrastructure of the mucin‐containing secretory granules of the conjunctival mucous cells is not necessarily homogeneous in character and further attention needs to be given to the effects of localised inflammation in the tissue and to possible hormonal influences.  相似文献   
43.
Consideration of new aspects of vascular anatomy of the pancreaticoduodenal region is required for further improvement of surgical procedures. Awareness of variations in arteries supplying the duodenum and pancreas can help in minimizing the blood loss during surgery. We report the absence of inferior pancreaticoduodenal artery, which was compensated by a large dorsal pancreatic artery arising from proximal part of the splenic artery. This artery replaced inferior pancreaticoduodenal artery and formed a large loop of anastomosis with the gastroduodenal artery. Key words: Variation, Splenic artery, Dorsal pancreatic artery, Inferior pancreaticoduodenal artery, Pancreas.  相似文献   
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Diabetes mellitus is a major cause of visual impairment and blindness. Twenty years after the onset of diabetes, almost all patients with type 1 diabetes and over 60% of patients with type 2 diabetes will have some degree of retinopathy. Prolonged diabetes retinopathy leads to maculopathy, which impairs the normal vision depending on the severity of damage of the macula. This paper presents a computer-based intelligent system for the identification of clinically significant maculopathy, non-clinically significant maculopathy and normal fundus eye images. Features are extracted from these raw fundus images which are then fed to the classifier. Our protocol uses feed-forward architecture in an artificial neural network classifier for classification of different stages. Three different kinds of eye disease conditions were tested in 350 subjects. We demonstrated a sensitivity of more than 95% for these classifiers with a specificity of 100%, and results are very promising. Our systems are ready to run clinically on large amounts of datasets.  相似文献   
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Cerebellum is unique in restraining amyloid-induced neurodegenerative changes. Amyloidosis and oxidant imbalance is common in aluminum exposure. Interestingly, aluminum itself does not pose any redox activity still it is associated with oxidant imbalance, and, it can aggravate the situation of already existing oxidant threat. Male rats were exposed to aluminum for 4 weeks along with exposure to 4 different doses of ethanol. After the treatment period, cerebellar level of protein, reduced glutathione (GSH), lipid perioxidation (TBARS) were measured. Activities of catalase, superoxide dismutase (SOD), glutathione reductase (GR) and glutathione perioxidase (GPx) were also estimated from the homogenized cerebellar tissue. In the present regimen of aluminum exposure, the cerebellum has shown significant reduction only in GPx activity. However, when aluminum was coexposed with ethanol, it contributed significantly to increase the cerebellar oxidant imbalance by (a) compromising the GSH restoration system, (b) reducing enzymatic peroxide scavenging system of cerebellum, (c) restricting the capability to cope with oxidative stress, as well as (d) downgrading the resistance to oxidative damage in response to chemical stress. Present study demonstrates that coexposure of aluminum with pro-oxidant favored development of aluminum-induced oxidative stress in cerebellum. These observations enlighten the role of pro-oxidants in the process of oxidative degeneration of cerebellum. With further studies, the present observation can be useful to understand the mechanism of neurodegenerative disorders and ways to ameliorate them.  相似文献   
48.
During regular dissection classes, we came across tripled falx cerebelli in a male cadaver. The main (middle) falx cerebelli was large and was attached to the internal occipital crest. It contained the occipital sinus. There were two smaller folds (right and left), one on either side of the falx cerebelli. There were two aberrant venous sinuses; each one connecting the ipsilateral sigmoid and transverse sinuses with each other. The complex dural-venous variation reported here is seldom reported in the literature. Knowledge of such variation is important for neurosurgeons and neuroradiologists as these aberrant folds could cause haemorrhage during suboccipital approaches or may lead to erroneous interpretation during imaging of the posterior cranial fossa.  相似文献   
49.
ObjectiveTo report a comparative clinical and histopathological study on oliguric and non-oliguric acute renal failure (ARF) in malaria.Method311 consecutive cases of malaria out of which 74 (23.79%) had ARF as per WHO criteria were conducted. Mean age was 32.58 (range 15–60 years) and male: female was 2:1.ResultMost of the cases developed ARF within 10 d of onset. 18 cases (11 falciparum, 2 mixed, 5 vivax) presented with oliguric and 56 (41 falciparum, 6 mixed, 9 vivax) with non-oliguric renal failure. Associated major manifestations were jaundice (75.68%), cerebral malaria (41.89%), bleeding manifestations (32.43%), severe anemia (27.03%), hypotension (25.68%), multi-organ failure (18.92%), severe thrombocytopenia (12.16%), and ARDS (8.11%). Kidney biopsy (n=20) showed acute tubular necrosis (n=7), Mesangioproliferative glomerulonephritis (n=4) or both (n=9). Hemodialysis was done in 8 cases of oliguric renal failure out of which 4 survived (average no. of session 2.9).ConclusionMost of the cases recovered within 3 weeks. Total mortality was 28.38% (n=21) and mortality was more in oliguric renal failure (72.22%) as compare to non-oliguric renal failure (14.29%).  相似文献   
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