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排序方式: 共有1644条查询结果,搜索用时 31 毫秒
101.
TP Jain DN Srivastava RP Sahu S Thulkar S Sharma S Mittal V Dadhwal 《Journal of Medical Imaging and Radiation Oncology》2007,51(3):246-252
The aim of this study was to determine the effectiveness of uterine artery embolization (UAE) as a primary treatment method in treatment of symptomatic fibroids, whether there are any preembolization MRI characteristics of fibroid predictive of reduction in volume and assess reduction in uterine and dominant fibroid volumes using ultrasound (US) and MRI. Study was carried out in total of 32 patients aged 25–49 years (mean 40.9 years). Uterine and dominant fibroid volume were determined using US and MRI before UAE, MRI and US at 3 months and US alone at 6 and 12 months post‐UAE, supplemented by clinical evaluation at interval of 3, 6 and 12 months. Procedure was carried out through unilateral femoral puncture using poly vinyl alcohol (PVA) particles 355–500 μm in size. All 32 patients had successful procedures. Overall, 25 patients responded, giving a clinical success rate of 78.12%. Mean reduction in volume of uterus and fibroid was 33 and 59.7% and 48.9 and 75.5% on US at 3 and 12 months respectively, and 33.3 and 58.6% on MRI at 3 months. Volume reduction on US and MRI at 3 months was highly correlative. There was no statistical difference in size reduction in volume of fibroids, which were hypointense or hyperintense on T2‐weighted image (T2WI) on pre‐UAE MRI. Uterine artery embolization leads to good technical success and fibroid volume reduction. Ultrasound alone may be used for follow up of patients post‐UAE. Preprocedure signal characteristics on T2WI are not predictors of volume reduction after UAE. 相似文献
102.
This study examined whether changes in the levels of the messenger RNAs (mRNAs) encoding the gamma-aminobutyric acid (GABA) synthesizing enzymes, glutamate decarboxylase (GAD)65 and GAD67 and transforming growth factor-alpha (TGFalpha) in the hypothalamus are correlated with the arrest of pulsatile GnRH release during infancy in the agonadal male monkey. This experiment also provided the opportunity to examine changes in hypothalamic GnRH gene expression during this critical phase of primate development. Male rhesus monkeys were castrated at 1 week of age: four were killed 4-7 weeks after orchidectomy while pulsatile GnRH release was robust as reflected by high circulating LH levels, and four were killed at 12-15 months of age after establishing that pulsatile GnRH release had been arrested. GAD65, GAD67, TGFalpha, and GnRH mRNA levels were estimated using RNase protection assays employing homologous probes and the results were expressed relative to cyclophilin mRNA levels. GnRH peptide was measured by RIA. GAD65 and GAD67 mRNA levels in the hypothalamus of juveniles were significantly greater than those in neonatal monkeys. On the other hand, hypothalamic TGFalpha and GnRH mRNA (and peptide) levels in agonadal neonate and juvenile monkeys were indistinguishable. These results indicate that the molecular concomitants associated with bringing the hypothalamic GnRH pulse generator into check in agonadal neonatal males are not a mirror image of those previously reported at the time this neuronal network is reactivated at puberty when TGFalpha and GnRH gene expression increase and GAD65 and GAD67 mRNA levels remain unchanged. Thus, the neurobiological mechanism that reactivates pulsatile GnRH release at puberty is likely to involve more than a simple reversal of that underlying inhibition of the same network in late infancy. 相似文献
103.
104.
The study assessed the impact of the Orissa supercyclone on survivors' locus of control, anxiety, depression, and posttraumatic stress. The study was conducted in structured interview sessions 3 months after the supercyclone. The affected people (n = 65) who were close to the epicenter of supercyclone and lost their family members, relatives, and property, experienced more anxiety, depression, and posttraumatic stress than the unaffected (n = 65) who were away from the epicenter of supercyclone and had not experienced any loss. Effects of exposure remained significant with the effects of sex and neuroticism controlled. External support reduced anxiety and depression, and the amount of loss experienced by the survivors significantly increased external locus of control and anxiety. 相似文献
105.
Macular serpiginous choroiditis 总被引:1,自引:0,他引:1
PURPOSE: To report a variant form of serpiginous choroiditis, that initially or predominantly involved the macular area. METHODS: Nine eyes of 6 patients with the macular form of serpiginous choroiditis were evaluated clinically and angiographically in a longitudinal fashion for a period of 12-36 months. The active stage and the recurrences were treated by oral and periocular cortico steroids; and two patients were supplemented with oral azathioprine. Most of these patients were referred to our center with varied diagnoses. RESULTS: In this group, 4 were male and 2 were female with an average age of 30.5 years. Three patients had bilateral macular lesions, two had typical serpiginous choroiditis in the fellow eye and the remaining one had unilateral macular involvement alone. The initial visual acuity was 6/60 or less in 60% eyes whereas the final visual acuity was 6/18 or better in 66% eyes. Angiographic findings were typical of serpiginous choroiditis characterised by early hypofluorescence followed by leakage and staining of the borders and the lesion itself without any evidence of choroidal ischaemia or retinal vascular abnormalities. CONCLUSION: The macular variant of serpiginous choroiditis can mimic many other macular pathologic lesions, thus posing a diagnostic dilemma. Because of its relentless destructive course, early diagnosis and prompt treatment is required to prevent sight-threatening complications. 相似文献
106.
Leptin signaling in the hypothalamus: emphasis on energy homeostasis and leptin resistance 总被引:18,自引:0,他引:18
Sahu A 《Frontiers in neuroendocrinology》2003,24(4):225-253
Leptin, the long-sought satiety factor of adipocytes origin, has emerged as one of the major signals that relay the status of fat stores to the hypothalamus and plays a significant role in energy homeostasis. Understanding the mechanisms of leptin signaling in the hypothalamus during normal and pathological conditions, such as obesity, has been the subject of intensive research during the last decade. It is now established that leptin action in the hypothalamus in regulation of food intake and body weight is mediated by a neural circuitry comprising of orexigenic and anorectic signals, including NPY, MCH, galanin, orexin, GALP, alpha-MSH, NT, and CRH. In addition to the conventional JAK2-STAT3 pathway, it has become evident that PI3K-PDE3B-cAMP pathway plays a critical role in leptin signaling in the hypothalamus. It is now established that central leptin resistance contributes to the development of diet-induced obesity and ageing associated obesity. Central leptin resistance also occurs due to hyperleptinimia produced by exogenous leptin infusion. A defective nutritional regulation of leptin receptor gene expression and reduced STAT3 signaling may be involved in the development of leptin resistance in DIO. However, leptin resistance in the hypothalamic neurons may occur despite an intact JAK2-STAT3 pathway of leptin signaling. Thus, in addition to defective JAK2-STAT3 pathway, defects in other leptin signaling pathways may be involved in leptin resistance. We hypothesize that defective regulation of PI3K-PDE3B-cAMP pathway may be one of the mechanisms behind the development of central leptin resistance seen in obesity. 相似文献
107.
Cyclosporine withdrawal from a mycophenolate mofetil-containing immunosuppressive regimen in stable kidney transplant recipients: a randomized,controlled study 总被引:10,自引:0,他引:10
Abramowicz D Manas D Lao M Vanrenterghem Y Del Castillo D Wijngaard P Fung S;Cyclosporine Withdrawal Study Group 《Transplantation》2002,74(12):1725-1734
BACKGROUND: Long-term maintenance immunosuppression with cyclosporine (CsA) is associated with chronic transplant nephropathy and adverse effects on blood pressure and lipid profile. Several nonrandomized studies suggest that CsA might safely be withdrawn from immunosuppressive regimens containing mycophenolate mofetil (MMF; CellCept). METHODS: A randomized, controlled study with 187 patients enrolled from 21 centers was conducted to compare CsA withdrawal with ongoing CsA therapy in stable renal transplant recipients receiving a triple-drug immunosuppressive regimen of MMF (2 g/day), CsA (Neoral), and corticosteroids. The primary endpoint was creatinine clearance at 6 months after complete withdrawal. RESULTS: In the intent-to-treat population, CsA withdrawal was associated with lower total cholesterol and low-density lipoprotein cholesterol (-0.3 mmol/L, P=0.02; -0.4 mmol/L, P=0.015). There was a trend toward improved creatinine clearance (4.5 mL/min, P=0.16) and serum creatinine (-1 vs. +4 micromol/L, P=0.34). In the per-protocol population, which excluded patients with acute rejections, the improvements in creatinine clearance and serum creatinine were statistically significant (7.5 mL/min, P=0.02; -11 vs. +4 micromol/L, P=0.0003). Reversible acute rejections, the majority of which were mild, occurred in nine CsA withdrawal versus two CsA continuation patients (10.6% vs. 2.4% of each group, P=0.03), with no graft loss. CONCLUSION: Withdrawal of CsA from an MMF-containing triple-drug immunosuppressive regimen improves renal function and lipid profile at the cost of a modest increase in acute rejections, without graft loss. 相似文献
108.
Long-term renal function in kidneys from non-heart-beating donors: A single-center experience 总被引:5,自引:0,他引:5
Gok MA Buckley PE Shenton BK Balupuri S El-Sheikh MA Robertson H Soomro N Jaques BC Manas DM Talbot D 《Transplantation》2002,74(5):664-669
BACKGROUND: Cadaveric kidneys from brain-stem-dead donors continue to be limited because the number of donors has reached a plateau. Wide recruitment of non-heart-beating donors (NHBD) could significantly increase the donor pool. NHBD renal transplants are underused because of the concern of poor quality graft function from such donors. In response to this perception, we reviewed 46 NHBD renal transplants performed in our center since 1998. METHODS: All NHBD kidneys were machine-perfused using the Newcastle continuous-hypothermic pulsatile preservation system before transplantation. A control heart-beating-donor (HBD) group was taken as the next consecutive HBD renal transplant to the NHBD transplant. The outcome and quality of function of the groups of renal transplants were analyzed for short-term and long-term performance. RESULTS: The renal transplant patients were matched for donor and recipient factors. Survival rates for allografts and patients were similar for 1 to 3 years. There was an increased incidence of delayed graft function in the NHBD renal transplants in the perioperative period. The creatinine clearance was 22.8+/-2.3 mL/minute for NHBD patients and 44.4+/-2.9 mL/minute for HBD patients at the time of discharge from hospital. This difference equalized after 3 months and the creatinine clearance for NHBD was 44.2+/-2.4 mL/minute and for HBD 49.2+/-3.4 mL/minute. CONCLUSIONS: Our results for NHBD renal transplants confirm that such grafts suffer primary warm ischemic injury, shown by the increased incidence of acute tubular necrosis and consequent delayed graft function. This produced poor renal function at the time of hospital discharge. After 3 months, the renal function of NHBD cases improved to the level seen in HBD patients. 相似文献
109.
Paul BN Prakash A Kumar S Yadav AK Mani U Saxena AK Sahu AP Lal K Dutta KK 《Biomedical and environmental sciences : BES》2002,15(3):215-222
Objective To investigate the pharmacological effect of Nyctanthes arbortristis (NAT) leaf extract in the prevention of lung injury induced by silica particles. Method Lung injury was induced in Swiss mice through inhalation exposure to silica particles (<5μ) using a Flow Past Nose Only Inhalation Chamber at the rate of -10 mg/m3 respirable mass for 5 h. Lung bronchoalveolar lavage (BAL) fluid collected between 48 and 72 h was subjected to protein profiling by electrophoresis and cytokine evaluation by solid phase sandwich ELISA. Lung histopathology was performed to evaluate lung injury. Results Inhalation of silica increased the level of tumor necrosis factor-α(TNF-α), and of the 66 and 63 kDa peptides in the BAL fluid in comparison to sham-treated control. Pre-treatment of silica exposed mice with NAT leaf extract significantly prevented the accumulation of TNF-α in the BAL fluid, but the 66 and 63 kDa peptides remained unchanged. The extract was also effective in the prevention of silica-induced early fibrogenic reactions like congestion, edema and infiltration of nucleated cells in the interstitial alveolar spaces, and thickening of alveolar septa in mouse lung. Conclusion NAT leaf extract helps in bypassing silica induced initial lung injury in mice. 相似文献
110.
The objective of this study was to examine whether hemispheric superiority is determined more by stimulus type (facial, lexical) or content (neutral, emotional). A split, visual-field experiment was designed using a computer-based program with bilateral presentation (left visual-field, right visual-field) for four sets of stimuli: face (neutral, emotional) x word (neutral, emotional), N = 40. The dependent measures were the frequency of correct response and response latency of correct responses. The visual-field effect was nonsignificant for correct responses; however, the interaction of stimulus type x content was found significant. The interaction of visual-field x stimulus type was significant with response time as the dependent measure. Facial stimuli were processed faster in the left visual-field (a right hemispheric function) and lexical stimuli were processed faster in the right visual-field (a left hemispheric function). No hemispheric effect was observed for stimulus content. 相似文献