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排序方式: 共有6417条查询结果,搜索用时 15 毫秒
1.
Hawwam Soha Abdalla Ismail Mayada El-Attar Yasmina Ahmed 《Lasers in medical science》2022,37(4):2193-2201
Lasers in Medical Science - Melasma is a chronic, dark brown–pigmented patches and macules commonly on the face. Many treatment modalities for melasma have been used as hydroquinone, laser... 相似文献
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Selda Sarikaya Bektas Acikg?z Ismail Hakki Tekk?k Y Yücel Güngen 《Journal of clinical neuroscience》2007,14(9):901-904
We report a 24-year-old woman with an intramedullary conus ependymoma associated with holocord syringohydromyelia and syringobulbia. The tumor was removed and surgery for decompression of the syringohydromyelia was not considered at the first operation. In the follow-up examinations, MRI showed significant and steady improvement of syringohydromyelia. Symptoms associated with syringohydromyelia also disappeared. The cause of syringohydromyelia accompanying intradural spinal cord tumors appears to be either direct blockade of the central canal or secondary interruption of the central canal flow by compression of the perimedullary cerebrospinal fluid flow. As removal of the mass often corrects both these likely causes of the syringohydromyelia, no additional treatment for the drainage of the hydromyelia cavity syrinx is usually necessary. 相似文献
5.
N. Glajchen S. Thomas P. Jowell S. Epstein M.D. F. Ismail M. Fallon 《Calcified tissue international》1990,46(1):28-32
Summary The paucity of information on the effect of long-term high-dose salmon calcitonin administration on normal bone mineral metabolism
and histology prompted an investigation of the influence of high-dose synthetic calcitonin in the rat. Serum ionized calcium,
osteocalcin or BGP (bone gla protein), and immunoreactive PTH were measured serially during calcitonin administration and
bone histomorphometry analyzed at 6 weeks (after sacrifice). Daily injections of salmon calcitonin, 0.4 IU/100 g (group B)
and 2 IU/100 g (group C), resulted in significant hypocalcemia at 4 hours for both experimental groups (P<0.004). Serium iPTH was significantly higher over the study period for both groups administered calcitonin. Serum BGP levels
were significantly lower than controls during the study in group C (P<0.002) and to a lesser extent in group B (P<0.05). In group C, bone histomorphometry revealed increased resorption (onteoclast count), decreased trabecular bone volume,
and decreased double-labeled tetracycline surface (bone formation). In group B an increase in osteoclast count but no alteration
in bone formation was observed. To assess the role of PTH in the above findings, high-dose calcitonin was administered to
parathyroidectomized rats. All of the above changes in bone histomorphometry were not observed in this group of animals. In
conclusion, high doses of calcitonin promote hypocalcemia, secondary hyperparathyroidism, and osteoclastosis in the normal
rat in a dose-dependent manner with very high-dose calcitonin impairing bone formation. 相似文献
6.
C M Misch C E Misch R R Resnik Y H Ismail 《The International journal of oral & maxillofacial implants》1992,7(3):360-366
Partially edentulous patients with alveolar defects contraindicating implant placement were treated with bone grafts obtained from the mandibular symphysis. Complications encountered were minor and uneventful. Evaluation 4 months after surgery revealed minimal graft resorption, thus implant placement was possible in all potential sites. Advantages of the symphysis graft include easy access, availability of greater quantities of bone over other intraoral donor sites, low morbidity, no hospitalization, minimal discomfort, no alteration in ambulation, and no cutaneous scar. Compared with other bone regenerative methods for implant placement, a superior quality of bone was found and a shorter healing period is required. Results of this preliminary clinical investigation demonstrate that chin grafts offer a viable alternative for reconstruction of alveolar defects prior to dental implant placement. 相似文献
7.
N D Vaziri M Ismail D C Martin E Gonzales 《The International journal of artificial organs》1992,15(6):365-369
Renal transplant recipients treated with cyclosporine (CS) have been reported to be at increased risk of thrombotic complications. The present study was intended to examine the blood coagulation, fibrinolytic, and inhibitory systems in such patients. Eight transplant recipients on maintenance immunosuppression with CS and prednisone were studied. Five transplant recipients maintained on azathioprine (AZA) and prednisone and 32 normal volunteers served as controls. Plasma antigen concentrations and/or activities of various proteins in the above pathways were measured. Both the CS and AZA groups exhibited significant elevations of factor IX activity, von Willebrand factor (vWF), D-dimer, protein C and tissue type plasminogen activator (t-PA) levels when compared with the normal controls. In addition, CS group showed a significant elevation of alpha 2-macroglobulin activity and AZA group showed a significant reduction in factor XII activity when compared with the normal controls. Comparison of data from CS and AZA groups revealed higher factor XII activity and vWF concentration in the former group. In conclusion, transplant recipients treated with long-term cyclosporine and prednisone exhibited significant elevation of plasma vWF, D-dimer and protein C concentrations. In addition, both CS and AZA-treated transplant recipients showed increased plasma concentrations of D-dimer and t-PA. The latter observations suggest in vivo thrombin generation, fibrin formation and degradation. 相似文献
8.
Lillian L. L. Leong Marian J. Sturm Yahya Ismail Charlene J. Stephens Roger R. Taylor 《Clinical and experimental pharmacology & physiology》1992,19(2):113-118
1. Phospholipase A2 (PLA2) cleaves phospholipids to produce a lyso-phospholipid and free fatty acid and, in view of the biological activity of the products, PLA2 may play a role in many disease states. Lyso-phospholipids and free arachidonic acid increase in ischaemic myocardium, indicating that ischaemia activates the enzyme. 2. Plasma PLA2 activity was measured in patients with acute myocardial infarction, based on the release of labelled arachidonic acid from Escherichia coli cell membrane. Fourteen males (peak serum creatine phosphokinase (CK) above twice upper normal) were studied on day 1 (within 6 h of chest pain onset), days 2-4, and days 6-9. Normal age matched males (n = 13) were also studied. 3. Plasma PLA2 in patients with uncomplicated myocardial infarction (n = 12) was, initially, 1.14 +/- 0.10 (s.e.m.) nmol/min per mL plasma, similar to that in the normal group (1.52 +/- 0.14). On days 2-4, PLA2 activity increased to 1.94 +/- 0.18 (P less than 0.001) and this activity was correlated with the earlier peak CK level (P less than 0.02). On days 6-9, PLA2 activity was 1.49 +/- 0.13 while in two patients who developed complications and underwent open-heart surgery between the last two measurements, there were further increases to 4.22 and 4.04 nmol/min per mL. 4. The increase in plasma PLA2 in uncomplicated myocardial infarction is likely to be due to release from the damaged myocardium; whether it contributes to pathophysiology is uncertain. 相似文献
9.
Effects of Hypothermia on Blood Endogenous Endotoxin Levels During Cardiopulmonary Bypass 总被引:1,自引:0,他引:1
Hakan Gerçekoglu M.D. Ozhan Tarim M.D. † Ismail Agar M.D. †† Ahmet Korukçu M.D. Hasan Karabulut M.D. Hüseyin Soydemir M.D. Onur Sokullu M.D. Hüseyin Toklu M.D. Candan B. Johansson Ph.D. † Besim Yigiter M.D. Ercüment Kopman M.D. †† 《Journal of cardiac surgery》1997,12(4):223-227
A bstract Endotoxin activates white blood cells and complement and produces a spectrum of clinical syndromes ranging from fever to septic shock. Although production of endogenous endotoxemia during cardiopulmonary bypass (CPB) has recently been reported, the role of hypothermia on endotoxemia is not clear. In this study, we evaluated the effects of moderate (24–28°C) and mild (32–34°C) hypothermia on blood endotoxin levels. The study population consisted of 20 patients who underwent coronary artery bypass grafting (CABG) with CPB. Moderate systemic hypothermia was applied during aortic cross-clamping in ten patients (group 1) and mild hypothermia in the remaining ten patients (group 2). The mean rectal temperatures were 26.8 ± 1.2°C in group 1 and 33.8 ± 0.8°C in group 2. The blood samples for endotoxin level measurements were obtained before CPB, during aortic cross-clamping, immediately after the release of the cross-clamp, 20 minutes after the release of the cross-clamp, after CPB, and 2 hours postoperatively. There were no endotoxins in any of the samples before CPB, but it was detected after CPB in both groups. The endotoxin levels were significantly higher in group 1 than in group 2. The present study suggests that when hypothermia is the technique of choice, the deleterious effects of endotoxemia on patients with comorbidity must be considered. 相似文献
10.
An entomological survey was carried out during 1986 in ten provinces of Syria representative of the main natural areas of this country. 932 sandflies were caught with aspirators in domestic resting sites. Captures are analysed for each species. 相似文献