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71.
Membrane NA+/H+ exchanger regulates cell pH, volume, and growth. Abnormal activities have been reported in essential hypertension and type I insulin-dependent diabetes mellitus (IDDM). The aim of this study was to analyze the relationship between erythrocyte NA+/H+ antiport activity and myocardial anatomical and functional parameters in normotensive type I insulin-dependent diabetic patients. We evaluated 26 insulin-dependent diabetic patients (20 normo- and 6 microalbuminuric) and 17 age- and sex-matched healthy controls. Plasma and urine analytes as well as erythrocyte NA+/H+ antiport rate were measured. M-Mode- and 2D echocardiograms with Doppler analysis were performed in all subjects. Diabetic people, both normo- and microalbuminuric, had a Na+/H+ antiport activity significantly higher than control subjects (p < 0.01). All echocardiographic parameters relative to left ventricular volume, cardiac mass and systolic function overlapped in the study groups. Of Doppler indexes, evaluating the left ventricular diastolic filling, the late peak flow velocity (peak A) was significantly higher in diabetic patients (p < 0.01). E/A ratio was heightened in the control group compared to diabetics, as a whole as well separately considered (p < 0.01). Antiport significantly correlated with PWTh, STh, E/A, UAER, serum sodium, and gender (p < 0.0001). The linear and significant correlation found between Na+/H+ exchange and some cardiac indexes suggest the increased Na+/H+ antiport activity as possible predictive risk factor for the development of diabetic cardiomyopathy.  相似文献   
72.
The avoidance of food(s) is the main therapeutic approach to food allergy. Nevertheless, orally- or sublingually-administered food allergens have gained attention and a number of food-allergic children can tolerate gradually increasing amounts of cow's milk and hen's egg. Our purpose is to show that oral desensitisation with food is an allergen-specific therapeutic approach and for this, we describe 4 illustrative children with IgE-mediated food allergy. The first was allergic to cow's milk and hen's egg, the second to cow's milk, hen's egg and fish. Both underwent oral desensitisation to both cow's milk and hen's egg. The third child was allergic to cow's milk, hen's egg and fish and underwent oral desensitisation with cow's milk. The last child was allergic to raw but not to cooked/boiled hen's egg and underwent the oral desensitisation with hen's egg. The first 2 children reached the clinical tolerance to cow's milk after the cow's milk oral desensitisation, but reached the hen's egg tolerance only after the hen's egg oral desensitisation. Moreover, the second child did not tolerate fish after being desensitised to both cow's milk and hen's egg. The third child tolerated cow's milk, but not hen's egg and fish, at the end of the cow's milk oral desensitisation. The fourth child could tolerate the previously not tolerated raw hen's egg after the oral desensitisation with raw hen's egg. In conclusion, we indicate that oral desensitisation with food is allergen specific. The induction of the clinical tolerance to one food is not followed by the tolerance to the other food(s) that the patient is allergic to. To obtain a double or multiple food tolerance, separate desensitisation protocols, one for each food, have to be carried out. Oral desensitisation with food discriminates between raw and cooked proteins.  相似文献   
73.
Strategy, Management and Health Policy
Enabling Technology, Genomics, Proteomics Preclinical Research Preclinical Development Toxicology, Formulation Drug Delivery, Pharmacokinetics Clinical Development Phases I‐III Regulatory, Quality, Manufacturing Postmarketing Phase IV
3,5‐Di‐t‐butylcatechol (DTCAT) stimulates the rat skeletal muscle sarcoplasmic reticulum ryanodine receptor (RyR). In the present study, its effects on the contractile response of diaphragm preparation were characterized using electrically stimulated phrenic nerve–diaphragm preparations and diaphragm strips. DTCAT reduced, concentration‐dependently, twitch contraction of the phrenic nerve–diaphragm preparation evoked by both direct and indirect stimulation and increased spontaneous tone. Twitch amplitude reduction was irreversible, while the increase of spontaneous tone was only partially reversible upon DTCAT washout. In diaphragm strips, caffeine > 4‐chloro‐m‐cresol >> 3,5‐diisopropylcatechol ? ryanodine > DTCAT enhanced spontaneous tone, whereas quercetin reduced it with all the compounds reducing twitch amplitude. DTCAT‐induced contracture was partly dependent on extracellular Ca2+ influx and antagonized by a Cd2+/La3+ mixture. In intact skeletal muscle preparations, DTCAT behaved as a RyR agonist.  相似文献   
74.
75.
Background: Adenoidectomy is a commonly performed ENT surgery. It is conventionally performed using the curettage method. This present article aims to evaluate endoscopic powered adenoidectomy as an alternative.  相似文献   
76.

Background

Adenoidectomy is a commonly performed ENT surgery. It is conventionally performed using the curettage method. This present article aims to evaluate endoscopic powered adenoidectomy as an alternative.

Methods

Sixty consecutive cases requiring adenoidectomy were randomized into two groups of thirty each. Group A underwent conventional adenoidectomy using the curettage method and Group B underwent endoscopic assisted micro-debrider adenoidectomy. The parameters studied were intra-operative time, intra-operative bleeding and completeness of resection, collateral damage, post operative pain and recovery time.

Result

Sixty cases of adenoidectomy were done using conventional surgery and powered endoscopic adenoidectomy in the study period from Aug 04 to Dec 05. The time taken in Group A (conventional surgery) varied from 22–39 minutes (95% Confidence Interval (CI) −27.7 – 30.9)and in Group B (powered endoscopic surgery) from 27–55 minutes(95% CI 36.6 – 41.9) (p<0.05). The average blood loss in Group A was 21 ml (range 10–50) as compared to 31.67 ml (range 10-60) in Group B (p<0.05). The resection was invariably complete in Group B whereas seven(23%) cases had more than 50% residual adenoid tissue in Group A. Three cases in group A had collateral damage whereas in Group B, there were no added injuries. Post operative pain was studied only in cases undergoing adenoidectomy alone. Group A (n=8) demonstrated a pain score of 1.64–2.63–3.63 (95% CI) whereas Group B (n=11) demonstrated a pain score of 1.19–2.13–3.06 (95% CI). This difference was not statistically significant. In group A, the mean recovery period was 3.5 days and 2.93 days in Group B(p<0.05).

Conclusion

Endoscopic powered adenoidectomy was found to be a safe and effective tool for adenoidectomy. The study parameters where endoscopic powered adenoidectomy fared better were completeness of resection, accurate resection under vision, lesser collateral damage and faster recovery time. On the other hand, conventional adenoidectomy scored in matter of lesser operative time and intra-operative bleeding.Key Words: Adenoidectomy, Powered adenoidectomy, Endoscopic adenoidectomy  相似文献   
77.
Gonadotropin hormone releasing hormone agonists (GnRHa) are commonly used in clinical practice to suppress gonadal hormone production in the management of various gynaecological conditions and as a treatment for advanced breast and prostate cancer. Animal and human behavioural studies suggest that GnRHa may also have significant effects on memory. However, despite the widespread use of GnRHa, the underlying brain networks and/or stages of memory processing that might be modulated by GnRHa remain poorly understood. We used event-related functional magnetic resonance imaging to examine the effect of GnRHa on verbal encoding and retrieval. Neuroimaging outcomes from 15 premenopausal healthy women were assessed at baseline and 8 weeks after Gonadotrophin Releasing Hormone analogue (GnRHa) treatment. Fifteen matched wait-listed volunteers served as the control group and were assessed at similar intervals during the late follicular phase of the menstrual cycle. GnRHa was associated with changes in brain response during memory encoding but not retrieval. Specifically, GnRHa administration led to a change in the typical pattern of prefrontal activation during successful encoding, with decreased activation in left prefrontal cortex, anterior cingulate, and medial frontal gyrus. Our study suggests that the memory difficulties reported by some women following GnRHa, and possibly at other times of acute ovarian hormone withdrawal (e.g. following surgical menopause and postpartum), may have a clear neurobiological basis; one that manifest during encoding of words and that is evident in decreased activation in prefrontal regions known to sub-serve deep processing of to-be-learned words.  相似文献   
78.
Chemoembolization of hepatocellular carcinoma with drug eluting beads   总被引:2,自引:0,他引:2  
Del Poggio P  Maddeo A  Zabbialini G  Pitì A 《Journal of hepatology》2007,47(1):157-8; author reply 159
  相似文献   
79.
Adiponectin/ACRP30 is an adipose tissue-derived hormone with antiatherogenic, antidiabetic, and insulin-sensitizing properties. Although the metabolic effects of adiponectin on glucose and lipid metabolism are well known, the signaling pathways triggered by adiponectin receptors remain to be elucidated. We report evidence that in hepatic cells, adiponectin stimulation produces a transient burst of reactive oxygen species (ROS) through activation of the small GTPase Rac1 and 5-lypoxigenase. Furthermore, adiponectin-induced oxidants cause the oxidation/inhibition of protein-tyrosine phosphatase (PTP) 1B, one of the major phosphotyrosine phosphatases involved in the control of insulin receptor phosphorylation. Adiponectin causes increased association of PTP1B to insulin receptor and the oxidation/inhibition of the phosphatase, ultimately provoking the ligand-independent trans-phosphorylation of insulin receptor. We also report evidence that redox signaling plays a key role in both mitogen-activated protein kinase activation and hepatic glucose consumption induced by adiponectin. CONCLUSION: These results point to ROS as critical regulators of the cross-talk between adiponectin and insulin pathways and provide a redox-based molecular mechanism for the insulin-sensitizing function of adiponectin.  相似文献   
80.
ObjectiveExtramedian spread of sensory symptoms is frequent in carpal tunnel syndrome (CTS) but its mechanisms are unclear. We explored the possible role of subtle ulnar nerve abnormalities in the pathogenesis of extramedian symptoms.MethodsWe recruited 350 CTS patients. After selection, 143 patients (225 hands) were included. The hand symptoms distribution was graded with a diagram into median (MED) and extramedian (EXTRAMED) pattern. We tested the correlation of ulnar nerve conduction measures with the distribution and the severity of symptoms involving the ulnar territory. The clinical significance of ulnar nerve conduction findings was explored with quantitative sensory testing (QST).ResultsEXTRAMED distribution was found in 38.7% of hands. The ulnar neurographic measures were within normal values. Ulnar nerve sensory measures were significantly better in EXTRAMED vs MED hands and not significantly correlated to ulnar symptoms severity. Ulnar and median nerve sensory measures were significantly correlated. QST showed normal function of ulnar nerve Aβ-fibers.ConclusionsUlnar nerve sensory abnormalities do not contribute to the spread of sensory symptoms into the ulnar territory.SignificanceOur data favour the hypothesis that spinal and supraspinal neuroplastic changes may underlie extramedian spread of symptoms in CTS.  相似文献   
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