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101.
BACKGROUND/PURPOSE: Vitamin D3 plays important roles in the absorption of calcium and phosphorus from the gastrointestinal tract and in the treatment of rickets; in addition, it facilitates the deposition of minerals in bones, thus minimizing the possibility of developing osteomalacia. Sunlight naturally induces vitamin D3 photosynthesis. Such a process is affected by a number of factors such as age, geographical location, skin color, sunscreen application and clothing. It is intended in the present investigation to study in vitro the effect of clothing on the solar photoproduction of vitamin D3. METHODS: Fifteen different fabric samples were tested for their effect on the efficiency of the in vitro solar conversion of 7-dehydrocholesterol (7-DHC) to vitamin D3. 7-DHC was dissolved in methanol to give a concentration of 2.6 x 10(-4) M. Solutions were exposed to sunlight in quartz containers for predetermined periods either uncovered or covered with the fabric sample under test. Changes in the concentrations of 7-DHC and the photoproducts were monitored by HPLC. Fabrics were graded as the number of threads per square inch (in(2)), and their sunlight attenuation was determined. RESULTS: 7-DHC is transformed to previtamin D3 upon exposure to sunlight, and the amount generated exhibited an almost linear relationship. When fabric-covered samples of 7-DHC were irradiated, photoproducts were also detected and their concentrations depended on the degree of sunlight attenuation imposed by the fabric. Generally, the higher the number of threads per in(2) the more the light attenuation produced. CONCLUSION: Clothing plays an important role in attenuating sunlight, thus leading to diminished vitamin D3 production to an extent that would require dietary compensation.  相似文献   
102.
Hemoglobins in unicellular organisms, like the one here in the bacterium Vitreoscilla, have greater chemical reactivity than their homologues in multicellular organisms. They can catalyze redox reactions and may protect cells against oxidative stress. The ability of Vitreoscilla hemoglobin to complement deficiencies of terminal cytochrome oxidases in Escherichia coli also suggests that this hemoglobin can receive electrons during respiration. In this study, a recombinant strain of Enterobacter aerogenes engineered to produce the Vitreoscilla Hb was investigated with regard to its susceptibility to oxidative stress. The culture response to oxidative stress produced by exogenously applied hydrogen peroxide was characterized in terms of cell growth, survival and the activities of two key antioxidant enzymes (catalase and superoxide dismutase). The influence of the physiological state of the cells and different media upon these culture dynamics was determined. Results showed that the hemoglobin-expressing strain is quite distinct in terms of growth/survival properties and activity of antioxidant enzymes from that of non-hemoglobin counterparts.  相似文献   
103.
The case of an eight-year-old girl with congenital double-orifice mitral valve associated with atrioventricular septal defect is reported. This rare mitral valve anomaly was diagnosed with two-dimensional echocardiography. The associated atrioventricular septal defect was repaired successfully. The central fibrous bridge between anterior and posterior mitral valve leaflets was left undivided to avoid iatrogenic mitral regurgitation. Preoperative diagnosis may provide some useful information to the surgeon. The surgical method can be individualized in each case.  相似文献   
104.
Retroperitoneal schwannoma is a rare tumor that originates in the neural sheath and accounts for only a small percentage of retroperitoneal tumors. Presentation is typically varied and non-specific ranging from abdominal pain, abdominal mass or an incidental finding and the diagnosis is quite often fortuitous being confirmed by anatomopathological study afterwards. We report 3 cases of benign retroperitoneal pelvic schwannoma with varied presentations. Main symptoms were abdominal and pelvic pain whereas a patient with left parailiac mass had urinary incontinence and left lower extremity pain. Surgical exploration and complete excision of tumors were successful. The histological diagnosis of the tumors was reported as benign schwannoma. All patients are doing well and had no symptoms of motor or sensory disturbances after surgery with a mean follow up of 18 mounts.  相似文献   
105.
Various classifications have been used for congenital anomalies of the Müllerian system. We report a case of a previously unknown anomaly of the uterus, and propose its possible embryological causes. The patient presented with primary amenorrhoea and infertility, and during laparoscopy three distinct uterine horns were observed. The tubes were connected to the two most lateral horns, each juxtaposed to a normal ovary. The middle horn had a seemingly normal attachment to the right uterosacral ligament, whereas its attachment to the left uterosacral ligament appeared attenuated and less normal. Furthermore, the right horn was immediately attached to the middle horn, whereas the left horn was, like its ipsilateral uterosacral ligament, attached to the middle horn by a more attenuated, stretched fibrous bridge. Only the middle horn, with its uterosacral ligaments, had an attached, although obstructed, cervix. Ultrasonographic examination revealed no endometrium echogeneity in any of these uterine bulbs. No etiologic factors were noted in the patient's history; her mother denied known ingestion of estrogens or other drugs while carrying her daughter. The pathogenesis of this anomaly cannot be clearly defined, but may involve sequential embryological errors of duplication of the Müllerian tracts, failure of fusion of each set of the Müllerian tracts with expected failed canalization of each tract and, finally, agenesis of the medial horn of the left duplicated tracts.  相似文献   
106.
BACKGROUND AND OBJECTIVE: Acute pancreatitis is an important and fatal disease with high mortality and morbidity. Although the pathogenesis of acute pancreatitis is poorly understood, there are many studies that suggest the role for oxygen free radicals (OFRs) in the development of pancreatitis and its complications and show beneficial effects of scavenger treatment. In the present study, we aimed to investigate whether Egb761, the standardized extract of gingko biloba, restrains the generation of OFRs and ameliorates the histopathologic findings of acute pancreatitis. MATERIALS AND METHODS: Sixty male Sprague Dawley rats were randomly assigned to one of the following experimental groups. In early and late pancreatitis and treatment groups, acute pancreatitis was induced by retrograde infusion of 3% sodium taurocholate. In treatment groups, 100 mg/kg Egb 761 was given intraperitoneally (IP) 24 h and immediately before induction of pancreatitis. Sham-operated rats received isotonic saline instead of sodium taurocholate. After observation times of 3.5 and 12 h, the pancreas was removed for light microscopy and determination of malondialdehyde (MDA) levels as a marker for OFRs-induced lipid peroxidation. Serum samples also were obtained for amylase and lipase levels. RESULTS: There was no significant difference in control and sham-operated groups in terms of histopathologic findings and serum enzyme levels. The tissue concentrations of MDA and serum enzyme levels were significantly elevated in early and late treatment groups as compared with the control group. The treatment with Egb 761 caused significant decrease in serum amylase and lipase levels and histopathologic scores as compared with early and late pancreatitis groups. CONCLUSIONS: Prophylactic application of Egb761 exerts highly beneficial influence on the course of acute pancreatitis, and this seems to be related to the oxygen radical scavenger effect of Egb761.  相似文献   
107.
108.
BACKGROUND: Localized fibrous tumors of the pleura, which are considered to originate from submesothelial connective tissue, are rare. The purpose of this study was to investigate the clinical features of these tumors and to determine the optimal treatment and follow-up. METHODS: The records of 10 consecutive patients with localized fibrous tumors of the pleura operated on at the Ataturk Center for Chest Diseases and Thoracic Surgery between 1995 and 2001 were retrospectively reviewed. Diagnostic procedures, clinical courses, and outcomes of these patients were studied. Total excision through a thoracotomy was performed in all of the patients. Pneumonectomy was required in 1 patient because of a giant intraparenchymal localized fibrous tumor of the pleura. Additional partial chest wall resections were done in 2 patients. RESULTS: The size of excised tumors ranged from 10 x 8 x 4 cm to 30 x 25 x 20 cm. Malignant transformation was seen in 1 patient 22 months after resection of a benign tumor. Four cases were pathologically considered to be malignant. All patients except 1 are alive (follow-up 16 to 57 months after resection). CONCLUSIONS: Although localized fibrous tumors of the pleura are considered histologically benign tumors, because of the risk of recurrence and malignant transformation, complete surgical resection is indicated and long-term follow-up is recommended in all patients.  相似文献   
109.
Cesur S  Akin K  Kurt H 《Hepato-gastroenterology》2003,50(53):1487-1489
BACKGROUND/AIMS: Mixed cryoglobulinemia is frequently seen in liver disease and chronic viral hepatitis. The aim of this study is to determine the prevalence and clinical findings of cryoglobulins in patients with chronic hepatitis B and chronic hepatitis C. METHODOLOGY: Cryoglobulins were precipitated from serum stored for up to 7 days. The precipitates were washed five times at 4 degrees C with 0.15 mol/L NaCl and total protein concentration was measured by reading absorbance at 280 nm. RESULTS: The prevalence of cryoglobulinemia was higher in patients with hepatitis C than in patients with hepatitis B (16.6% and 4.6% respectively). Patients with cryoglobulinemia had several symptoms such as arthralgia and weakness. CONCLUSIONS: Cryoglobulin-positive chronic hepatitis B and C patients should be investigated in terms of cryoglobulinemia symptoms and complications.  相似文献   
110.
Lipoma arborescens (LA) (diffuse articular lipomatosis, synovial lipomatosis, Hoffa disease) is a rare intra-articular lesion of unknown etiology. This article presents three patients who had LA, which was diagnosed in the knee in two patients and in the wrist of the third patient. Details of the clinical and histomorphological examination and treatment, in addition to a review of the literature, are discussed. The article concludes that in patients with a slow increase in painless swelling of the joints, unresolving articular pain with or without limited motion, or intermittent effusions following a minor trauma, LA should be considered in the differential diagnosis. It should be remembered that LA occurs in joints other than the knee, such as the elbow, shoulder, and wrist. Although recommended surgery involves arthrotomy and synovectomy, arthroscopic synovectomy may be a useful treatment modality, particularly in the larger joints as the recurrence rate is low.  相似文献   
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