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排序方式: 共有726条查询结果,搜索用时 15 毫秒
31.
32.
Özlem Yildirim Nurcan Aras Ateş Lülüfer Tamer Özay Öz Ayça Yilmaz Uĝur Atik Handan Çamdeviren 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》2005,243(4):327-333
Purpose To find out whether the polymorphism at GSTM1, GSTT1 and GSTP1 loci is associated with increased susceptibility to glaucoma.Methods We genotyped 153 primary open angle patients and 159 healthy controls. Genomic DNA from peripheral blood was examined using polymerase chain reaction and defined for the genetic polymorphisms of glutathione S-transferase.Results The frequency of the GSTM1 null genotype individuals among the glaucoma patients was significanlty higher than in controls (54.9 vs 40.9%) with odds ratio of 1.64 (95% CI: 1.10–2.59). The frequency of the GSTT1 and GSTP1 in both groups were not statistically different.Conclusion The present study suggests that the GSTM1 null genotype may be a genetic risk factor for development of primary open angle glaucoma. Further associations studies in other polymorphic genes for xenobiotic–metabolizing enzymes are needed to elucidate the environmental-genetic interaction in the underlying cause of primary open angle glaucoma. 相似文献
33.
Effect of changes in renal perfusion pressure on the suppression of proximal tubular sodium reabsorption due to saline loading 总被引:11,自引:11,他引:0 下载免费PDF全文
Norman Bank Karl M. Koch Hagop S. Aynedjian Marc Aras 《The Journal of clinical investigation》1969,48(2):271-283
Rapid intravenous infusion of saline is known to suppress reabsorption of sodium and water in the proximal tubule. It has previously been shown that this suppression is accompanied by two changes which in combination might account for the over-all decrease in reabsorption: a reduction in the intrinsic reabsorptive capacity of the tubular epithelium (C/pir(2)) and a reduction in the ratio between tubular volume and GFR (pir(2)d/V(o)). The present micropuncture experiments were carried out in order to study the possible role of altered peritubular physical forces (hydrostatic and colloid oncotic pressure) in mediating these two changes. Proximal tubular reabsorptive capacity, transit time, fractional reabsorption of sodium and water, pir(2)d/V(o), and intratubular hydrostatic pressure were measured in saline-loaded rats during acute changes in renal perfusion pressure induced by intermittent constriction of the abdominal aorta.We found that when renal perfusion pressure was lowered to 70-90 mm Hg, the usual effects of saline loading on C/pir(2), pir(2)d/V(o), and fractional reabsorption in the proximal tubule were greatly minimized. When the aortic clamp was released and renal perfusion pressure allowed to rise, C/pir(2), pir(2)d/V(o), and fractional reabsorption fell markedly to levels characteristically seen in saline diuresis. Reclamping of the aorta reversed all of these changes.In order to determine whether the changes in C/pir(2) accompanying changes in renal perfusion pressure were mediated by a circulating natriuretic hormone, we assayed in hydopenic rats the dialysate of plasma collected from saline-loaded rats during and after release of aortic constriction by the split oil drop method. No significant difference in reabsorptive half-time (t(1/2)) was found between the two dialysates, and t(1/2) with both dialysates was approximately the same as was found when isotonic saline was injected in the tubules of hydropenic control animals. These observations suggest that the large changes in C/pir(2) which occurred with changes in renal perfusion pressure in saline-loaded rats were not mediated by a circulating hormone. We suggest that the reduction in C/pir(2), pir(2)d/V(o), and fractional reabsorption which occurs in the proximal tubule during a saline diuresis is related to the rise in hydrostatic pressure within the kidney. 相似文献
34.
The aim of this study was to determine the effect of a mechanical bowel preparation on postoperative surgical wound infections
in patients treated with identical antimicrobial prophylaxis undergoing wide excision and primary closure for chronic pilonidal
sinus disease. Patients more than 18 years old were included in the study. All patients had intravenous antimicrobial prophylaxis
at the time of anesthesia induction. In a prospective, randomized setting, patients were allocated to either the bowel preparation
group or the no-bowel-preparation group. Mechanical bowel preparation was performed using an oral sodium phosphate solution.
On the morning of the procedure a rectal enema was performed with the phosphate solution. The primary outcome measure was
the rate of wound infection, but all postoperative complications and recurrences were recorded. All patients were actively
observed for 1 year after discharge. The overall infection rate for the entire study population was 12.8% (13/101) including
14.3% (7/49) of those who had had the bowel preparation and 11.5% (6/52) of those with no bowel preparation. There was no
statistically significant difference between groups (P = 0.680). The mean rate of recurrence for all 101 patients was 4.9% (5/101) at 19.2 months (range 12–32 months) of follow-up.
The recurrence rate was 6.1% (3/49) in the bowel preparation group and 3.8% (2/52) in the no-bowel-preparation group (P = 1.000). Although the number of patients is small in this study, our results showed that the mechanical bowel preparation
does not cause a decrease in the rate of surgical wound infections after excision and primary closure in patients with chronic
pilonidal sinus disease. 相似文献
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Erdoğan MF Küçük NO Anil C Aras S Ozer D Aras G Kamel N 《Nuclear medicine communications》2004,25(11):1083-1087
BACKGROUND: Autonomously functioning toxic adenomas are a common cause of hyperthyroidism. Although 131I seems to be a good therapeutic option with little postablative hypothyroidism for these patients, only a small number of recent studies have objectively evaluated changes in nodule size by ultrasonography following radioiodine therapy. METHODS: We prospectively followed 39 patients with a mean age of 51.2 (35-75) years for 12 months and the patients who remained toxic thereafter, until euthyroidism was provided. Thyroid function tests, sonographic volumes were determined initially and 3, 6 and 12 months after treatment. Radioiodine doses of 3.7 MBq.g(-1) thyroid tissue corrected to a 100% 24 h 131I uptake were given. Thirty patients received a single dose, two required two doses and three required three to five doses of 131I due to persistent thyrotoxicosis. Sonographic volumes of the diffuse parts of the glands decreased significantly by 18% from a mean+/-SD value of 50+/-27.6 ml to 41+/-27.4 ml by the end of the 12 months. A significant decrease (8.3%, P=0.002) was achieved in the first three months. Toxic adenomas decreased in size more efficiently (54%) from a mean of 26+/-24 ml to 12+/-10 ml during 12 months, but also most significantly (28.8%, P=0.003) in the first 3 months of the follow-up. Thirty of the patients (76.9%) became euthyroid at the end of 12 months of follow-up. Four patients (10.3%) became overtly hypothyroid during the follow-up. CONCLUSION: Single or multiple doses of radioiodine can successfully treat toxic adenomas with a low rate of hypothyroidism and considerable nodule-volume reduction. 相似文献
38.
The MicAB two-component signaling system is involved in virulence of Streptococcus pneumoniae 下载免费PDF全文
In Streptococcus pneumoniae, the two-component signaling system MicAB was previously shown to contribute to repression of competence when oxygen is limited. In virulent strains expressing the serotype 2 and 6 capsule, mutation of the MicB kinase reduced the lag period of growth when cultures were switched from an aerobic to anaerobic atmosphere. After intranasal challenge of mice, the micB::km mutation decreased virulence, as shown by the absence of symptoms and by a lower level of recovery of CFU from lungs and blood. It is proposed that MicAB is involved in the adaptive response of the bacteria to changes in oxygen level during the course of infection. 相似文献
39.
A 37-year-old, experienced female diver developed gastric rupture due to rapid ascent from a depth of 37 meters. The incident was preceded by a heavy meal, intake of soda beverages, swallowing of air and water under water, and panic. Sharp abdominal pain was present immediately after surfacing and afterwards. Full abdominal distension developed within two hours after the ascent. No other diving-related pathology was found. Surgery was performed around three hours after the accident and revealed pneumoperitoneum, gastric rupture, gastric content in the abdomen cavity, and signs of acute peritonitis. On surgery, a 4-cm rupture of the lesser curvature was found and sutured. The patient was discharged eight days after the event. 相似文献
40.
The relation between tooth loss and bone mass in postmenopausal osteoporotic women in Turkey: a multicenter study 总被引:3,自引:0,他引:3
Gur A Nas K Kayhan O Atay MB Akyuz G Sindal D Akşit R Oncel S Dilsen G Cevik R Gunduz OH Ersoy Y Altay Z Ozturk C Akkus S Senocak O Kavuncu V Kirnap M Tekeoglu I Erdogan F Sarac AJ Demiralp L Demirkesen A Adam M 《Journal of bone and mineral metabolism》2003,21(1):43-47
The purpose of this study was to investigate the associations of tooth loss with skeletal bone mass, years since menopause,
educational level, current smoking status, dietary calcium intake, and number of pregnancies in postmenopausal osteoporotic
women in Turkey. The study population consisted of 1171 postmenopausal women aged 40–86 years (mean age, 61.19 ± 7.28 years).
A detailed history was obtained from all women, including relevant lifestyle parameters, risk factors, and measurements of
weight and height. Women were separated into three groups according to the number of teeth remaining as group 1 (edentulous,
457 women), group 2 (10 or fewer teeth, 232 women), and group 3 (more than 10 teeth remaining, 482 women). There was no significant
difference among the three groups in mean age and menopausal age (P < 0.05). Body mass index of group 1 was significantly higher than that of group 2 (P < 0.01). Educational level was significantly different between three groups: groups 1 and 2 (P < 0.001), groups 1 and 3 (P < 0.0001), and groups 2 and 3 (P < 0.001). Educational level was lowest in group 1 and highest in group 3. Despite a low ratio of cigarette smoking in general,
a smoking habit was most prevalent in group 3 and least in group 2. The ratio of women receiving adequate calcium was significantly
lower in group 1 than in other groups (P < 0.001); mean calcium intake was similar in all groups. The number of pregnancies was significantly higher in group 1 than
in other groups (P < 0.001). Lumbar bone mineral density (BMD) of group 1 was significantly lower than that of groups 2 and 3 (P < 0.001). Although no significant difference was found between groups 1 and 3, femoral neck BMD of group 2 was less than in
others, and differences between groups 1 and 2 and between groups 2 and 3 (P < 0.001) were significant. Lumbar bone mineral content (BMC) of group 1 was significantly lower than that of groups 2 and
3 (P < 0.001), and lumbar BMC in group 2 was significantly higher than in group 3 (P < 0.05). Femoral neck BMC in group 1 was significantly higher than in groups 2 and 3 (P < 0.001). In conclusion, lumbar BMD and BMC in the edentulous group were significantly lower, whereas femoral neck BMD and
BMC were significantly higher in edentulous group compared with the others. Our findings indicated that improvement in lifestyle
factors and nutritional strategies for the treatment and prevention of osteoporosis may have additional benefit in reducing
tooth loss.
Received: February 18, 2002 / Accepted: June 21, 2002
Offprint requests to: A. Gur 相似文献