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451.
452.

Objective

The well-known relation of Helicobacter pylori to the MALT-lymphoma and gastric carcinoma suggested a possible presence in the laryngeal tissues of patients with squamous cell carcinoma of the larynx by using Polymerase Chain Reaction (PCR) investigations, and PCR results of benign laryngeal pathologies were compared.

Methods

Polymerase Chain Reaction investigations were carried out in biopsy samples of 21 patients with squamous cell carcinoma of the larynx and of 19 patients with benign laryngeal pathologies like vocal polyp and nodules.

Results

The PCR results of 17 out of the 21 samples (80.9%) of the patients with laryngeal squamous cell carcinoma were positive for H. pylori. Moreover, any genomic material of H. pylori was not found in the PCR results of the 19 patients with benign laryngeal pathology. It was also determined that the presence of the H. pylori in the patients with laryngeal squamous cell carcinoma was statistically significant (p = 0.0001).In the patients with laryngeal squamous cell carcinoma, the comparison of the H. pylori presence within the normal and tumoral tissues revealed that 16 normal tissue samples (76.19%) were positive, while 9 of the tumoral tissue samples (42.85%) were positive. The ratio of bacterial presence in both the normal and tumor tissue samples was 38.09% (8 patients). The rates of presence revealed a statistically significant difference between the normal and tumoral tissue samples (p = 0.039).

Conclusions

The presence of the genomic material of H. pylori within the laryngeal tissue of patients with squamous cell carcinoma of the larynx is a proof of the colonization of the bacterium in that tissue. While this may suggest a possible relation of the bacterium to the development of laryngeal squamous cell carcinoma, no conclusion is possible to be drawn about the mechanism of the process.  相似文献   
453.
Vacuolar myelopathy (VM) in leukemia is rare. We report a boy with leukemia who developed isolated central nervous system (CNS) relapse during reinduction therapy. 5 months after cranial radiotherapy, he gradually developed quadriparesis. Magnetic resonance imaging revealed an intramedullary lesion which extended through the cervical spine. Serum vitamin B12, folic acid, cerebrospinal fluid methyl malonic acid were normal. Viral screening by ELISA was negative. He had lymphopenia, and reduced immunoglobulins, from a cardiac arrest. Biopsy revealed VM. He responded to weekly vitamin B12 treatment but on the 6th week of the therapy he died after developing periventricular, gliotic, hyperintense lesions in the brain.  相似文献   
454.
Background: This study set out to document the early electrophysiological and immunohistochemical changes that occur in the retina of experimentally induced diabetic rats. Methods: Diabetes was induced in rats by intraperitoneal injection of 60 mg/kg of streptozotocin (STZ). Electroretinogram readings were taken monthly under either short‐duration or long‐duration stimuli for up to 3 months after STZ. Oscillatory potentials (OP) and the amplitudes and implicit times of a‐ and b‐waves were analysed, and b‐wave amplitudes were analysed using a Naka–Rushton fit. Scotopic a‐waves were analysed with photoreceptor models, and Rmp3 (the maximum a‐wave amplitude) and S (sensitivity) were calculated. Three months after STZ injection, immunohistochemistry for glial fibrillary acidic protein was performed on the retinas of the STZ‐treated rats and age‐matched controls. Results: The implicit OP times were significantly longer in the diabetic rats as compared with the controls, and this difference was noted as early as 1 month following STZ treatment. Other electrophysiological parameters, such as OP amplitudes, a‐ and b‐wave amplitude as well as the implicit times, did not differ from controls at this stage. The sacrificed STZ‐treated rats also demonstrated marked enhancement of glial fibrillary acidic protein immunoreactivity, suggesting that at least in experimentally induced diabetic retinopathy there is increased Müller cell reactivity. Conclusion: The results of this study indicated that functional alterations in the retina develop rapidly after the onset of diabetes. Analysis of each electroretinogram component may be useful in further investigating the development mechanisms of diabetic retinopathy.  相似文献   
455.
A girl with congenital dysgranulopoietic neutropenia (CDN) and her non-neutropenic mother with aphthae (A) were investigated. Apoptosis in lymphocytes and granulocytes of both patients (mother A+) were documented by high annexin and electron microscopic morphology. CD11b/CD18 of the daughter's granulocytes ranged between low to normal while that of the mother changed between very low to high levels through A(-) to A(+) periods. In both patients, CD11b/CD18 on lymphocytes were high; GM-CSF receptor was negative; CD4-/CD8- lymphocytes were high and the leukocytes which showed abnormal cell cycle were stained by senescence associated beta-galactosidase. We think that increased apoptosis and rapid cell senescence of leukocytes underlies the pathophysiology of CDN.  相似文献   
456.
Cellular response to hypoxia involves signaling via Smad proteins   总被引:11,自引:1,他引:10  
  相似文献   
457.
Cholesterol granuloma is usually associated with middle ear disease and is very rare in the paranasal sinuses. We report a case of cholesterol granuloma originating in the maxillary sinus of a 36-year-old female. Endoscopic sinus surgery was performed on the left maxillary, sinus, and the cholesterol granuloma was successfully removed by the middle meatal antrostomy.  相似文献   
458.
The Melnick-Needles syndrome (MNS) is a rare bone dysplasia with characteristic clinical and radiologic diagnostic findings. The diagnosis of MNS was made for the patient reported in this paper clinically and radiologic confirmation was done afterwards. Her left fibula was shorter than the right one. She had lateral insufficiency in her left ankle and could not bear weight on her left foot. A fibular length discrepancy of 2 cm was assessed. Her ankle-hindfoot score was 49 according to the American Orthopedic Foot and Ankle Society (AOFAS) clinical rating system for ankle and hindfoot. Simple fibular lengthening was performed with a unilateral external fixator. Two centimetres of fibular lengthening was obtained in 14 weeks. Her AOFAS ankle-hindfoot score was 82 after 27 months of follow-up. Ankle stability and plantigrade foot were achieved and the result was satisfactory.  相似文献   
459.
Neonatal diabetes mellitus (NDM) is defined as hyperglycemia occurring in the first few weeks of life. It can be either transient (TNDM) or permanent (PNDM). A 25 days old newborn was brought to the hospital with restlessness, respiratory depression and cyanosis. He was born at term with a birth weight of 2,000 g. There was no consanguinity between his parents. His physical examination findings were as follows: Weight and height were under 3th percentile, he was hypoactive and dehydrated. Serum glucose level was 800 mg/dl; C-peptide was 0.41 ng/ml. Upon investigation for dyslipidemia in association with his neonatal diabetes, hyperchylomicronemia was found both in the patient and his father. Pancreatitis, anemia and cholestasis were also observed. Insulin treatment was started for his diabetes together with a special diet for dyslipidemia. At the end of 28 months of follow-up, dyslipidemia has resolved but the need for insulin therapy was still existing. However, TNDM was considered in differential diagnosis because he was small for gestational age (SGA) at birth and his symptoms had started at the 25th day of the neonatal period. Delayed recovery from insulin dependency brought out the possibility of PNDM. Furthermore, neonatal diabetes combined with hypechylomicronemia is a rare clinical picture. Reported cases of NDM with different clinical evaluation will help to better understanding of this disorder.  相似文献   
460.
Neutrophil production and functions are immature in newborns. Although neutrophil kinetics during neonatal period have been widely studied, little is known about the effect of apoptosis on these defects. In this study, we examine the apoptosis of neonatal neutrophils and the effects of colony-stimulating factors (CSF) on this process. The study was performed using three different methodologies (morphological analysis, surface Fas expression, and mitochondrial 7A6 antigen expression) and the results were compared with adult controls. Neonatal neutrophils more rapidly underwent apoptosis in comparison to adult neutrophils. The above-mentioned three different methods gave similar results. Granulocyte-CSF (G-CSF) and granulocyte-macrophage CSF (GM-CSF) decreased the apoptosis of neutrophils in newborns and adults. This effect was significantly more pronounced in adults than newborns in morphological analysis. Increased apoptosis may contribute to qualitative and quantitative defects of neutrophils during neonatal period and may be an explanation for the proneness of newborn to develop neutropenia during systemic infections.  相似文献   
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