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61.
Overexpression and mutation of epidermal growth factor receptors (EGFR) have been shown to be important in the prognosis of several cancers, including head and neck cancers. However, our inability to define the activation status of these and other receptors limits our ability to assess the importance of these pathways and to exploit effectively new molecularly targeted treatments directed at their catalytic activities. Here we describe the use of automated, high-throughput fluorescence lifetime imaging microscopy to measure EGFR autophosphorylation status by fluorescence resonance energy transfer (FRET) in head and neck tumors. We have correlated FRET efficiency with the clinical and survival data. The results from head and neck arrays show that high FRET efficiency is correlated with worsening disease-free survival but not with overall survival. This powerful tool could be exploited as a new independent quantitative prognostic factor in clinical decisions and cancer management.  相似文献   
62.
Oxidative stresses are increasingly implicated in the pathogenesis of diabetic complications which may either cause direct pancreatic beta-cell damage or lead to metabolic abnormalities that can induce or aggravate diabetes. The valuable effect of antioxidant nutrients on the glycemic control of diabetic patients has been reported in experimental and clinical studies. The present study was designed to investigate the effects of the herbal medicine, Silybum marianum seed extract (silymarin), which is known to have antioxidant properties on the glycemic profile in diabetic patients. A 4-month randomized double-blind clinical trial was conducted in 51 type II diabetic patients in two well-matched groups. The first group (n = 25) received a silymarin (200 mg) tablet 3 times a day plus conventional therapy. The second group (n = 26) received the same therapy but a placebo tablet instead of silymarin. The patients were visited monthly and glycosylated hemoglobin (HbA(1)c), fasting blood glucose (FBS), insulin, total cholesterol, LDL and HDL, triglyceride, SGOT and SGPT levels were determined at the beginning and the end of the study. The results showed a significant decrease in HbA(1)c, FBS, total cholesterol, LDL, triglyceride SGOT and SGPT levels in silymarin treated patients compared with placebo as well as with values at the beginning of the study in each group. In conclusion, silymarin treatment in type II diabetic patients for 4 months has a beneficial effect on improving the glycemic profile.  相似文献   
63.
Vitamin D (Vit D) is an essential element for the regulation of serum calcium, phosphate, and alkaline phosphatase (Alk Ph). Because the Vit D serum level is not usually measured directly, Vit D deficiency is diagnosed indirectly by changes in serum calcium, phosphate, and Alk Ph leves. The current study assessed the status of these biochemical parameters in subjects with different degrees of Vit D deficiency. We selected 1210 subjects, between 20 and 69 years old, randomly from the Tehran population. Subjects with diseases or medications that modified bone metabolism were excluded from the study. Serum 25(OH) D, calcium, phosphate, Alk Ph, and parathyroid hormone (PTH) levels were measured and the status of these biochemical parameters was compared in subjects with different degrees of Vit D deficiency. Vit D deficiency was diagnosed in 79.6% of the subjects. Different degrees of Vit D deficiency were classified as follows: group 1, severe; group 2, moderate; and group 3, mild. Serum PTH levels in the Vit D-deficient groups were significantly higher than that in group 4 (normal Vit D). Serum calcium and phosphate levels in groups 1 and 2 were significantly lower than those in groups 3 and 4. No significant difference was seen in serum Alk Ph in the groups with different degrees of Vit D deficiency. The sensivity for at least one biochemical variable (calcium, phosphorus, or Alk Ph) for the detection of severe, moderate, and mild Vit D deficiency was 24.2%, 13.8%, and 6%, respectively. When the serum 25(OH) D level was reduced to less than 25 nmol/l (groups 1 and 2), the effects of Vit D deficiency on calcium and phosphate levels were obvious. Therefore, the usual biochemical parameters (calcium, phosphate, Alk Ph) alone do not have sufficient sensitivity to detect mild deficiency of Vit D.  相似文献   
64.
65.
Amrinone is a positive inotropic and vasodilatory compound being used to improve cardiocirculatory function in chronic cardiac failure. The linearity of the pharmacokinetics of amrinone was examined in New Zealand white rabbits given i.v. bolus doses of 1.5, 3.0, and 7.5 mg/kg amrinone. Blood samples were obtained serially for a period of 6 hours following amrinone administration. Serum concentration-time data were analyzed by nonlinear least squares regression, as well as non-compartmental techniques. There were no differences as a function of dose in the systemic clearance, elimination half-life, mean residence time, or average concentration of amrinone. The pharmacokinetics of amrinone appear to be linear in rabbits. The rabbit may be useful as an animal model to study various aspects of amrinone pharmacokinetics.  相似文献   
66.
STUDY OBJECTIVE: To evaluate the effectiveness of intravenous patient-controlled analgesia (PCA) in patients after surgery. DESIGN: Prospective, observational study. SETTING: University teaching hospital. PATIENTS: Sixty patients with American Society of Anesthesiologists physical status I-III receiving intravenous PCA for postoperative pain. The PCA was programmed to deliver morphine 1 mg or hydromorphone 0.1-0.2 mg, with a lockout interval of 10 and 6 minutes for 80% and 20% of the patients, respectively. MEASUREMENTS AND MAIN RESULTS: Patients were asked, up to 4 times during PCA use and once within 4 hours after PCA use, to describe and rate their intensity of pain at rest and after activity. During the first 12 hours of intravenous PCA use, 75% of the patients reported moderate-to-severe pain > or = 5 on a verbal numeric rating scale) at rest, 80% after activity. Corresponding values, respectively, were 33% and 72% for the 12-24-hour period, 43% and 76% for the 24-36-hour period, and 36% and 64% for the 36-48-hour period of intravenous PCA use. Within 4 hours of stopping PCA, 30% and 58% of the patients had moderate-to-severe pain at rest and after activity, respectively. In approximately 50% of patients, presence of pain was described with words signifying sensory and affective dimensions of pain. Pain control was rated as good or very good by 54% of patients during the first 12 hours of intravenous PCA. Ratings of pain control tended to improve with time. CONCLUSION: Successful postoperative pain management using PCA is difficult to achieve on a consistent basis unless treatment is individualized. Our data support the hypothesis that small fixed doses fail to achieve adequate relief in many patients.  相似文献   
67.

Background

First and second-degree heart blocks are partly common rhythm disorders in thalassemic patients but complete heart block is a very rare complication of iron overload cardiomyopathy.

Case Presentation

This 15-year-old boy, a known case of major β-thalassemia was admitted to our emergency unit with dyspnea and cough because of decompensated heart failure. The electrocardiogram showed complete heart block with junctional escape rhythm. Interestingly, his previous electrocardiogram taken 2 months earlier, had some PVC and second degree, Mobitz type 1 (Wenckebach) heart block. After improvement of dyspnea and control of blood pressure in normal range, the patient was referred to ER. A dual-chamber permanent pacemaker was implanted and his symptoms improved, but he died 24 days after discharge from hospital.

Conclusion

We present a rare case of complete heart block after a second-degree (Mobitz 1) heart block that was due to severe iron overload cardiomyopathy.  相似文献   
68.
The functions of ghrelin, a novel weight-regulatory peptide, have not been intensively investigated in primitive fish. This experiment was conducted to determine whether ghrelin has a specific effect on growth hormone (GH), prolactin and cortisol levels in Persian sturgeon (Acipenser persicus). Juvenile Persian sturgeons with a mean body weight of 320?±?30?g were given a single injection of ghrelin at three doses of 0.1, 1 and 10?ng/g body weight. Control animals were injected with vehicle (sterile saline) only. Blood samples were collected at 0, 2, 4, 8, 24, 48 and 72?h after injection. The level of plasma hormones were determined by ELISA kit. As expected, ghrelin injection significantly elevated plasma GH (P?<?0.05), whereas prolactin levels did not significantly change after injection (P?>?0.05). Plasma cortisol levels decreased in fish injected with high doses of ghrelin (P?<?0.05). Ghrelin at 10?ng/g body weight had the most influence on GH release, and 1?ng/g ghrelin injection caused the lowest level of cortisol. These results show for the first time that ghrelin induces some plasma hormonal changes in sturgeon fish, as lower vertebrates, but more investigations are needed in this area.  相似文献   
69.
Immunophenotyping of lymphocytes is very essential for evaluation of immune system. Due to the effect of environmental factors and ethical diversity on immune system, establishment of an internal normal range of lymphocyte subsets is a necessity for each population. The aim of this study was to determine the normal range of T and B lymphocytes, and NK cells in normal Iranian adults. Two hundred and thirty three Iranian normal adult volunteers took part in this study. Complete Blood Count (CBC) was performed for them with Sysmex (KX21) and cells with CD3, CD4, CD8, CD19 and CD16/56 surface markers were simultaneously detected by flow cytometry method with FACstar system. Their percentile and absolute count were determined.The volunteers were 150 male and 83 female. Mean percentages of lymphocyte subpopulation were: CD3 (67.66 ±7.76), CD19 (14.41±5.09), CD4 (39.22±6.7), CD8 (25.42 ±5.4) and CD16/56 (10.14±6.42). Also, their mean absolute count of lymphocyte bearing CD3, CD19, CD4 and CD8 were 1,504±505/μl, 332±186/μl, 827±313/μl and 522±185/μl, respectively.Our results are comparable with similar Asian results from other Asian population, but are different from European population, we therefore conclude that it is necessary for each laboratory to establish an internal normal range for the lymphocytes bearing above- mentioned markers.  相似文献   
70.
Acute necrotizing mediastinitis (ANM) is a lethal disease which without antibiotic therapy and surgical intervention can lead to about 40% mortality. With the development of imaging technology, spiral computed tomography (CT) scanning and shortening of the time of diagnosis and surgery, the prognosis of these patients is excellently improved. This study describes the clinical presentation, management and outcome of 4 patients (mean age: 35 years) with ANM. All patients were operated on by a trans-cervical approach, and only one patient was operated on by a trans-thoracic one. After surgery, patients were transferred to the intensive care unit and underwent daily washing and debridement with antibiotic treatments. Odontogenic infection (2 cases), pharyngeal perforation and cervical esophageal perforation were the causes of the ANM. Infection of cervical space (perivisceral spaces) and superior Mediastinum were found in all patients, and Infection below the carina was found in two. All patients were discharged with a good, general condition after an average of 24 days. Early diagnosis of ANM with clinical presentation and on-time CT scanning, early drainage and careful post operation care are very important in the management of patients with ANM and can improve the outcome of trans-cervical drainage to an acceptable technique.  相似文献   
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