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排序方式: 共有1367条查询结果,搜索用时 15 毫秒
101.
Ertekin MV Tekin SB Erdogan F Karslioglu I Gepdiremen A Sezen O Balci E Gündogdu C 《Journal of radiation research》2004,45(4):543-548
There is currently substantial clinical interest in zinc (Zn) as a protective agent against radiation-related normal tissue injury. To further assess this drug's potential, the effect of Zn was studied in rats using a radiation-induced skin injury model. Sprague-Dawley rats were divided into four groups. Group 1 received neither Zn nor irradiation (control group). Group 2 received 30 Gy of gamma irradiation as a single dose to the right hind legs of the rats (RT Group). Groups 3 and 4 received the same irradiation plus 5 mg/kg/day Zn (RT+5 Zn group) or 10 mg/kg/day Zn orally (RT+10 Zn group), respectively. The rats were irradiated using a cobalt-60 teletherapy unit. Acute skin reactions were assessed every three days by two independent radiation oncology experts. At the endpoint of the study, light-microscopic findings were assessed by two independent expert pathology physicians. Clinically and histopathologically, irradiation increased dermatitis when compared with the control group (p < 0.05). The severity of radiodermatitis of the rats in the RT+5 Zn and RT+10 Zn groups was significantly lower than in the RT group (p < 0.05); radiodermatitis was seen earlier in the RT group than in the other groups (p < 0.05). Zn was found to be efficacious in preventing epidermal atrophy, dermal degeneration such as edema and collagen fiber loss, and hair follicle atrophy. The most protection for radiation dermatitis was observed in the RT+10 Zn group. It would be worthwhile studying the effects of zinc sulphate supplements in radiation-treated cancer patients, in the hope of reducing radiation-induced toxicity. 相似文献
102.
Lahjouji K Elimrani I Wu J Mitchell GA Qureshi IA 《Molecular genetics and metabolism》2002,76(1):76-80
The juvenile visceral steatosis (jvs) mouse, having a mutation in the carnitine transporter gene Octn2, is a model of primary systemic carnitine deficiency in humans (SCD, OMIM 212140). Like humans with SCD, homozygous jvs -/- mice have hepatic and cardiac steatoses, reduced plasma and tissue carnitines, and increased urinary carnitine clearance. Because symptomatic heterozygotes have been reported for some fatty acid oxidation disorders, including SCD, we compared the jvs heterozygotes to normal control mice. We measured the free and esterified carnitine, total cholesterol, and triglycerides in adult liver samples, myocardium, and skeletal muscle. Our results indicate significant differences between the livers of nonfasting adult normal (n = 8) vs jvs heterozygotes (n = 8) (means +/- SEM, p < 0.01) for the following parameters: free carnitine, 2.28 +/- 0.36 nmol/mg protein vs 0.41 +/- 0.13; total carnitine, 3.48 +/- 0.36 vs 1.27 +/- 0.25; triglycerides, 0.14 +/- 0.04 vs 0.39 +/- 0.02; and total cholesterol, 0.21 +/- 0.02 vs 0.39 +/- 0.04, but not for esterified carnitine, 1.18 +/- 0.17 vs 0.90 +/- 0.17 (p > 0.05). There is also a negative correlation between hepatic free carnitine and triglycerides from jvs heterozygotes (p < 0.05). Similar results were obtained with myocardium and skeletal muscle. We conclude that free and total carnitine levels are significantly lower in the heterozygote mouse liver and heart while triglyceride and total cholesterol levels are significantly higher. We speculate that in situations of lipolytic stress, some SCD heterozygotes might develop clinical symptoms of carnitine deficiency. 相似文献
103.
Endothelial function,insulin sensitivity and inflammatory markers in hyperprolactinemic pre-menopausal women 总被引:3,自引:0,他引:3
Yavuz D Deyneli O Akpinar I Yildiz E Gözü H Sezgin O Haklar G Akalin S 《European journal of endocrinology / European Federation of Endocrine Societies》2003,149(3):187-193
BACKGROUND: Hyperprolactinemia has been reported to be associated with abnormalities of carbohydrate metabolism. The aim of this study was to evaluate the effects of hyperprolactinemia and bromocriptine (Brc) treatment on endothelial function, insulin sensitivity and inflammatory markers in pre-menopausal women. METHODS: Sixteen hyperprolactinemic pre-menopausal women with pituitary adenomas were recruited and 20 healthy subjects were included as controls. Patients were given Brc in doses of 2.5-20 mg/dl until normal levels of prolactin were reached. Prior to treatment and 2 months after prolactin levels were normalized, the following tests were performed. Insulin sensitivity was determined by an oral glucose tolerance test based on a formula named the insulin sensitivity index (ISI composite). Endothelial function was measured as flow-mediated dilatation (FMD) on a brachial artery using high resolution ultrasound. RESULTS: Serum glucose, insulin, estrogen, highly sensitive C-reactive protein (hsCRP), fibrinogen, homocysteine and uric acid levels were measured. Calculated ISI composite and FMD were significantly lower in the hyperprolactinemic group in comparison with the controls and improved after Brc treatment. Serum homocysteine, hsCRP and uric acid levels were significantly higher in hyperprolactinemic patients than in the controls and returned to normal levels with Brc treatment. Serum prolactin concentrations were inversely correlated with FMD measurements (r=-0.68; P<0.0001), ISI composite (r=-0.48; P<0.005) and serum estrogen (r=-0.54; P<0.005), and positively correlated with serum homocysteine concentrations (r=0.55; P<0.0001) in the hyperprolactinemic group. CONCLUSIONS: The hyperprolactinemic state is associated with impaired endothelial function and decreased insulin sensitivity, which are early markers of atherosclerosis. These alterations may predispose to the development of atherosclerosis in non-treated cases. Correction of the hyperprolactinemic state is associated with improved endothelial function and insulin sensitivity. 相似文献
104.
Orbital schwannoma: correlation of magnetic resonance imaging and pathologic findings 总被引:3,自引:0,他引:3
Kaan?GündüzEmail author Carol?L.?Shields Ilhan?Günalp Esra?Erden Jerry?A.?Shields 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》2003,241(7):593-597
Purpose To report the correlation between magnetic resonance imaging (MRI) findings and histopathology of orbital schwannomas.Methods This study is a retrospective noncomparative interventional case series of three consecutive patients with orbital schwannoma. After preoperative MRI, all patients underwent orbitotomy and tumor removal. Histopathologic and immunopathologic studies of the excised tumors were performed. The main outcome measures were MRI features, histopathology, and their relationship to the cohesiveness of the tumor.Results The patients ages were 56 years (patient 1), 43 years (patient 2), and 18 (patient 3) years. MRI demonstrated that the tumors were well-circumscribed, intraconal in patient 1, superior extraconal in patient 2 and inferotemporal extraconal in patient 3. The tumor in patient 1 had a partly cavitary appearance, while the tumors in patients 2 and 3 had a solid appearance on MRI. The tumor had heterogeneous signal intensity in patients 1 and 2 and homogeneous signal intensity in patient 3 on T2-weighted images. All patients underwent orbitotomy and tumor removal. In patients 1 and 2, the tumor was gelatinous and fragmented during removal. The fragments were completely excised in patient 1 and an incomplete piecemeal tumor excision was made in patient 2. In patient 3, complete excision without fragmentation was performed. Pathologic examination revealed that the tumor was of Antoni B pattern in patient 1, mixed Antoni A and B patterns in patient 2, and marked Antoni A pattern in patient 3. At a mean follow-up of 23.7 months (range: 22–26 months) after surgery, all patients retained preoperative visual acuity. Patient 2 developed recurrence at 21 months follow-up and underwent Krönlein orbitotomy for excision of the recurrent tumor.Conclusions MRI is useful in depicting both the anatomic location and internal consistency of orbital tumors. Schwannomas with MRI evidence of cavitary change or heterogeneous signal intensity on T2-weighted images were found to have marked Antoni B pattern on histopathology, imparting a friable structure and fragmented excision.An erratum to this article can be found at 相似文献
105.
The influence of sex hormones on ocular blood flow in women 总被引:1,自引:0,他引:1
Toker E Yenice O Akpinar I Aribal E Kazokoglu H 《Acta ophthalmologica Scandinavica》2003,81(6):617-624
PURPOSE: To investigate the influence of sex hormones on ocular haemodynamics, blood flow velocities in the ophthalmic and central retinal arteries and serum levels of sex hormones were measured in pre- and postmenopausal women. METHODS: Colour Doppler imaging (CDI) was used to determine the flow velocities (peak systolic velocity [PSV] and end-diastolic velocity [EDV]) and the resistive index (RI) in the ophthalmic and central retinal arteries in 22 premenopausal and 32 postmenopausal women, who had never received hormone replacement therapy. Serum levels were measured for oestradiol, free testosterone and follicle-stimulating hormone. The CDI parameters were compared between the two groups and the influence of serum levels of oestradiol and testosterone on blood flow velocities and the resistive indices were analysed. RESULTS: After correcting for age and mean arterial blood pressure, an analysis of covariance disclosed a significantly lower EDV (p=0.02) and a significantly higher RI (p=0.01) in the central retinal artery of postmenopausal women compared with premenopausal women. Partial correlation analysis, controlling for age, revealed significant correlations between the CDI parameters and serum levels of oestradiol and testosterone. For premenopausal women, PSV (r=0.58, p=0.04) and EDV (r=0.73, p=0.006) in the ophthalmic artery correlated positively with serum oestradiol levels. The RI in the central retinal artery decreased with increasing oestradiol levels in both groups (premenopausal r= -0.40, p=0.04; postmenopausal r= -0.32, p=0.05). Peak systolic velocity in the central retinal artery correlated negatively (r= -0.49, p=0.04), whereas the RI correlated positively (r=0.53, p=0.02) with testosterone levels in the premenopausal group. Postmenopausal women with higher testosterone levels had lower EDV (r= -0.53, p=0.007) in the central retinal artery and higher RI in both vessels (ophthalmic artery r=0.48, p=0.01; central retinal artery r=0.61, p=0.002). CONCLUSION: Our data provide evidence of a relationship between serum sex hormone levels and blood flow velocities and resistive indices in retrobulbar arteries. Oestradiol appears to have beneficial effects on ocular haemodynamics, whereas testosterone may act as an antagonistic to the effects of oestrogen. 相似文献
106.
Erdemli O Ayik I Karadeniz U Yamak B Birincioğlu CL Cağlar K 《Anesthesia and analgesia》2003,97(3):650-653
We describe a 45-yr-old woman with an intermediate type atrioventricular septal defect associated with a double-orifice left atrioventricular valve (DOLAV). We diagnosed this exceptional anomaly by intraoperative transesophageal echocardiography (TEE) during surgery that was scheduled for only a primum type atrial septal defect (ASD) repair. Preoperative transthoracic echocardiography and angiography revealed the ASD but could not demonstrate the DOLAV. We were able to repair this rare and challenging abnormality successfully under the guidance of TEE imaging during the operation. TEE provides valuable information about both anatomy and functional aspect of the valvular structures. Besides its proven role in cardiac surgery, intraoperative use of TEE also serves as a useful tool for diagnosis of such unexpected and potentially missed abnormalities. 相似文献
107.
108.
Ayaz T Akansel G Hayirlioglu A Arslan A Suer N Kuru I 《European journal of radiology》2003,46(3):244-249
OBJECTIVE: To evaluate the hemodynamic changes in mild-moderate preeclampsia using ophthalmic artery Doppler ultrasonography technique. METHODS: Ophthalmic artery pulsatility and resistivity indices were calculated in 30 mild-moderate preeclamptic women and 30 normotensive gravid women of matched gestational age. Student's t-test was performed to test the significance of difference. RESULTS: Both indices of peripheral resistance were found to be significantly lower in the ophthalmic arteries of mild-moderately preeclamptic women than those measured in normotensive gravid women at similar stage of pregnancy. In a small number patients whose disease progressed to severe preeclampsia, both indices increased. CONCLUSION: In patients with mild-moderate preeclampsia, ophthalmic artery color Doppler ultrasonography detects hemodynamic changes that are not present in normotensive gravid women. Reversal of Doppler patterns in a small number of patients with progressive disease supports the hypotheses suggesting the presence of early vasodilation and late vasospasm in the etiology of preeclampsia. 相似文献
109.
EditorAbout one-third of long-term insulin-dependent(type I) diabetics present with laryngoscopic difficulties.1This is due, at least in part, to diabetic stiff joint syndromecharacterized by a short stature, joint rigidity, and tightwaxy skin.2 The fourth and fifth proximal phalangeal jointsare most commonly involved. Patients with diabetic stiff jointsyndrome have difficulty in approximating their palms and cannotbend their fingers backwards (the prayer sign, Fig. 1).This is due to non enzymatic glycosylation of 相似文献
110.
Evaluation of the mastoid air cell system by high resolution computed tomography: three-dimensional multiplanar volume rendering technique 总被引:3,自引:0,他引:3
Koç A Ekinci G Bilgili AM Akpinar IN Yakut H Han T 《The Journal of laryngology and otology》2003,117(8):595-598
The mastoid air cell system is an important contributor to the pathophysiology of middle-ear inflammatory disease. The mastoid cavity is not only an air reservoir, but also an active space for gas exchange. Various methods of temporal bone imaging have been designed to investigate mastoid pneumatization. In this study, we examined 100 normal temporal bones for the evaluation of mastoid pneumatization. Mastoid air cell systems were measured by reconstructed axial and coronal high resolution computed tomography (HRCT) images. The reconstructions were made by a three-dimensional multiplanar volume rendering (3D MPVR) technique. The mean volume of the mastoid air cell pneumatization was 7.9 cm(3) (4.0-14.0 cm(3), SD = 2.3 cm(3)). The ears were allocated to the groups with respect to measured mastoid air cell pneumatization. Twenty-eight per cent of the ears have small pneumatization with an air cell system not exceeding 6 cm(3). Fifty-two per cent had an air cell system between six and 10 cm(3), and 20 per cent had an air cell system exceeding 10 cm(3). With its excellent imaging quality and the ability to eliminate bone and soft tissue, HRCT is the best method for evaluating the mastoid air cell system. The 3D MPVR technique must be used to measure the temporal bone/mastoid pneumatization for the best results. 相似文献