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101.
Kidney transplants between strains of mice which are incompatible at either the K or the D end of the H-2 complex usually function for prolonged periods supporting the lives of nephrectomized recipients. This occurs with no recipient treatment. With multiple H-2 and non-H-2 determined incompatibilities, transplants may be rejected but more slowly than skin grafts. In the strain combination studied most extensively in these experiments (B10.D2 to B6AF(1)) in which the incompatibility was confined to the K end of the H-2 region, about 70 percent of recipients survived for many weeks with normal blood urea nitrogen levels. Skin grafts between untreated members of these strains were rejected promptly (mean survival time of 13.5 +/- 1.1 days) as were kidney transplants to recipients of prior skin grafts. Donor strain skin grafts to recipients of kidney transplants after kidney transplantation enjoyed greatly prolonged survival whereas skin grafts from a third party (A.SW) were rejected normally. If kidney tissue was transferred in the form of free grafts without primary vascular union, it was rejected promptly leaving its recipient highly immunized. Cellular and humoral immunity to donor antigens declined over the first few weeks after transplantation, and the spleens of long-term recipients contained no “killer cells.” Recipient lymphoid cells could mount active graft versus host reactions to donor strain antigens on transfer to neonatal mice. Nevertheless, they were distinctly less able to respond specifically by the production of killer cells to donor strain antigens after sensitization in vitro. No evidence that this defect was associated with the presence of suppressor cells was forthcoming from several types of in vivo and in vitro tests.  相似文献   
102.
103.
目的:观察白藜芦醇对豚鼠、小鼠和家兔离体心肌收缩力和心率的影响。方法:实验于2005-08/2006-12在河北医科大学西校区实验中心完成。①实验分组:离体豚鼠、小鼠和家兔心肌各分为9组:空白对照组、溶剂对照组、递增累积浓度白藜芦醇组(浓度为10-6,3×10-6,10-5,3×10-5,10-4,3×10-4mol/L),白藜芦醇对照组(5×10-5mol/L),ATP敏感性钾通道阻断剂格列苯脲(5×10-5mol/L)预孵育 白藜芦醇组,钙激活钾通道阻断剂四乙胺(10-3mol/L)预孵育 白藜芦醇组,电压依赖性钾通道阻断剂4-氨基吡啶(10-3mol/L)预孵育 白藜芦醇组,内向整流钾通道阻断剂氯化钡(10-4mol/L)预孵育 白藜芦醇组,乙酰胆碱调节钾通道阻断剂阿托品(10-5mol/L)预孵育 白藜芦醇组。②实验方法:不同类型的钾通道阻断剂均预孵育15min后,分别加入白藜芦醇(终浓度为5×10-5mol/L),连续记录30min,与相应动物白藜芦醇对照组相比较。③评估指标:分析不同阻断剂与白藜芦醇联用对心房收缩力下降率及心率抑制率的影响。结果:①白藜芦醇可降低豚鼠和小鼠离体心肌收缩力和心率(P<0.05),并被ATP敏感性钾通道阻断剂格列苯脲和钙激活钾通道阻断剂四乙胺部分阻断。②白藜芦醇可降低家兔离体心肌心率,格列苯脲可阻断白藜芦醇的负性变时作用。③电压依赖性钾通道阻断剂4-氨基吡啶、内向整流钾通道阻断剂氯化钡、乙酰胆碱调节钾通道阻断剂阿托品均不能阻断白藜芦醇对3种不同动物离体心房收缩力和心率的作用(P>0.05)。结论:白藜芦醇可呈剂量依赖性减慢豚鼠、小鼠和家兔的心率,白藜芦醇可减弱豚鼠心肌收缩力,其作用是与开放ATP敏感性钾通道有关,而与电压依赖性钾通道、内向整流钾通道和乙酰胆碱调节钾通道无关。同时,钙激活钾通道也参与了白藜芦醇对豚鼠和小鼠离体心房收缩力和/或心率的抑制作用。白藜芦醇对离体心肌收缩力和心率的作用有种属差异性。  相似文献   
104.
A severe, life-threatening metabolic alchalosis associated with a stenosing pancreatic carcinoma in a female type II diabetic patients is presented, and a review of the most frequent causes of hyperemesis, orthostatic hypotension and lethargy is shown.  相似文献   
105.
To evaluate the effectiveness of intravenous clodronate in ameliorating refractory bone pain in patients with metastatic bone disease, 60 patients with established osseous metastases and persistent bone pain were randomized to receive either clodronate (600 mg or 1500 mg in 500 mL of normal saline) or 500 mL of saline as placebo. After 2 weeks, the patients were crossed over to receive the alternate treatment. After another 2 weeks, each patient and investigator made a blinded choice. Daily visual analogue scales (VAS) and analgesic diaries were recorded throughout the study period. Forty-six patients were evaluable (77%). A treatment × period interaction was identified in the VAS and daily morphine equivalent dose (DATED) scores. First period analysis of the VAS scores for general pain, pain at rest, and pain upon movement demonstrated an average reduction of 13, 14, and 24 mm, respectively, from baseline, but were not significantly different from changes following placebo. The average change in DMED was −6 .4 (SE = 2.9) following clodronate and was +24.6 (SE = 14.9) following placebo (p = 0.03). In the blinded choice of which agent resulted in improvement in pain, 26 (57%) patients chose clodronate, 12 (26%) chose placebo, and eight (17%) had no preference (p = 0. 0021). For the investigators who also made a blinded selection, clodronate was chosen in 30 (65%) patients, placebo in ten (22%) patients, and no difference was apparent in six (13%) (p < 0.0001). Intravenous clodronate appeared to have analgesic effect in patients with refractory bone pain due to metastatic bone disease. The optimal dose and duration of effect require further evaluation, particularly in patients with stable disease and persistent bone pain.  相似文献   
106.
Clinical measurement of swallowing in health and in neurogenic dysphagia   总被引:8,自引:0,他引:8  
We studied clinical features potentially related to dysphagia and three indices from a timed test of swallowing--average volume per swallow (ml), average time (s) per swallow and swallowing capacity (ml/s)--in 181 screened healthy adults and 30 patients with motor neurone disease (MND). In healthy adults, age, sex and height accounted for 44.3% and 55.6% of the variance of log average volume per swallow and log swallowing capacity, respectively. Symptoms and signs were more prevalent in the MND group and were associated with reduced swallowing capacity and reduced average volume per swallow; repeatability studies on these two indices in both groups showed that the median difference between the mean of two recordings on successive days and the mean of all recordings (6-15 over 3 days) was < 5% (maximum third quartile 12.8%, indices expressed as percent predicted according to age and sex). Using this simple bedside test, swallowing function can be quantified on a ratio scale and expressed as percent of that predicted by age and sex; such information may improve the predictive value of clinical assessment and provides a practical way of monitoring change in patients with dysphagia.   相似文献   
107.

INTRODUCTION

Published colorectal cancer surgery data suggest no role for the analysis of the anastomotic doughnuts following anterior resection. The usefulness of routine histological analysis of the upper gastrointestinal doughnut is not clear. Our study assessed the impact of cancer involvement of the doughnut on clinical practice. Factors associated with doughnut involvement and the effect on patients'' survival were also analysed.

PATIENTS AND METHODS

The clinicopathological details of 462 patients who underwent potentially curative oesophagogastrectomy for cancer with a stapled anastomosis between 1994 and 2006 in two specialist centres were retrospectively analysed. Univariate, multivariate and survival analyses were carried out.

RESULTS

Approximately 5% of doughnuts (22 of 462) were histologically involved with cancer. Microscopic involvement of the proximal resection margin, local lymph node metastasis and lymphatic invasion within the main resected specimen were independently associated with doughnut involvement (all P < 0.05). However, these three factors taken together failed to predict doughnut involvement. Doughnut involvement was an independent adverse prognostic factor for overall survival (P = 0.0013).

CONCLUSIONS

In contrast to findings in colorectal surgery, doughnut involvement with cancer appears to have useful prognostic information following oesophagogastrectomy. Routine histological analysis of upper gastrointestinal doughnuts is justified. Doughnut involvement could potentially strengthen the indications for adjuvant therapy in the future.  相似文献   
108.
109.

OBJECTIVES:

To compare the metabolic, hemodynamic, autonomic, and endothelial responses to short-term red wine consumption in subjects with hypercholesterolemia or arterial hypertension, and healthy controls.

METHODS:

Subjects with hypercholesterolemia (n=10) or arterial hypertension (n=9), or healthy controls (n=7) were given red wine (250 mL/night) for 15 days. Analyses were performed before and after red wine intake.

RESULTS:

Red wine significantly increased the plasma levels of HDL-cholesterol in the controls, but not in the other groups. The effects on hemodynamic measurements were mild, non-significantly more prominent in healthy subjects, and exhibited high interindividual variability. Across all participants, mean blood pressure decreased 7 mmHg (p <0.01) and systemic vascular resistance decreased 7% (p = 0.05). Heart rate and cardiac output did not significantly change in any group. Red wine enhanced muscle sympathetic fibular nerve activity in hypercholesterolemic and hypertensive patients, but not in controls. At baseline, brachial artery flow-mediated dilation was impaired in patients with hypercholesterolemia and arterial hypertension; red wine restored the dilation in the hypercholesterolemic group but not in the hypertensive group.

CONCLUSIONS:

Red wine elicits different metabolic, autonomic, and endothelial responses among individuals with hypercholesterolemia or arterial hypertension and healthy controls. Our findings highlight the need to consider patient characteristics when evaluating the response to red wine.  相似文献   
110.
Lung cancer is the leading cause of cancer-related deaths in the Western world. The lungs can be affected by a number of histologically diverse malignancies. Nonetheless, the vast majority of lung cancers are classified as non-small-cell lung cancer (NSCLC). Despite extensive research on different therapeutic regimens, the overall 5-year survival of patients diagnosed with NSCLC (all stages) is a dismal 15%. Although strongly correlated with tobacco smoke, there is an increasing NSCLC morbidity in individuals who have never smoked. The pattern of genetic lesions found in NSCLC derived from smokers and never-smokers appears to be different. This fact led to the hypothesis that different, still unidentified carcinogens are responsible for lung cancer onset in never-smokers. All the aforementioned considerations compel the scientific community to find novel therapeutic targets to fight such a deadly disease. In recent years critical pathways governing embryonic development have been increasingly linked to cancer. Here we will focus on the role of Notch signaling in lung cancer. Notch receptors' activity can be blocked through the use of different strategies, thus representing a promising alternative/complement to the arsenal of therapeutic strategies currently used to treat lung cancer.  相似文献   
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