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41.
Cadmium is a toxic heavy metal element, which probably cause infertility by impairment in spermatogenesis. The present work aimed (i) to study the toxic effect of cadmium on spermatogenesis in rat, as well as (ii) the protective effect of Crocus sativus L. on cadmium‐intoxicated rats. Cadmium chloride was administered intraperitoneally during 16 days at intervals of 48 h between subsequent treatments. Crocus sativus L. was pre‐treated in both of control and cadmium‐injected rats. Animals were sacrificed on day 17 after the first treatment. The left cauda epididymis was removed and immediately immersed into Hank's balanced salt solution for the evaluation of sperm count and viability, and left testis was fixed in 10% formalin for histological evaluation. Following contamination with cadmium, a decrease was observed in the number and viability of cauda epididymis sperm, which were increased by Crocus sativus L. pre‐treatment (P < 0.05). In addition, cadmium decreased both cell proliferation and Johnsen Scores in the seminiferous tubules, which were reversed by Crocus sativus pre‐treatment (P < 0.05). Furthermore, cadmium‐induced decrease in the amount of free serum testosterone as well as an increase in lipid peroxidation activity in the testicular tissue was reversed by Crocus sativus L. (P < 0.05). These findings may support the concept that Crocus sativus L. can improve the cadmium toxicity on spermatogenesis.  相似文献   
42.
INTRODUCTION: Tempol is a permeant nitroxide superoxide dismutase (SOD) mimetic that lowers mean arterial pressure (MAP) in spontaneously hypertensive rats (SHRs). We investigated the hypothesis that the antihypertensive response entails a negative salt balance, blunting of plasma renin activity (PRA), endothelin-1 (ET-1), or catecholamines or correction of oxidative stress as indexed by 8-isoprostane prostaglandin F(2alpha) (PGF(2alpha)) (8-Iso). METHODS: Groups (N= 6 to 8) of SHRs were infused for 2 weeks with vehicle or tempol (200 nmol/kg/min) or given tempol (2 mmol/L) in drinking water. RESULTS: Tempol infusion reduced the MAP of anesthetized SHRs (150 +/- 5 vs. 126 +/- 6 mm Hg) (P < 0.005). Oral tempol did not change the heart rate but reduced the MAP of conscious SHRs (-23 +/- 6 mm Hg) (P < 0.01) but not Wistar-Kyoto (WKY) rats. Tempol infusion increased the PRA (2.2 +/- 0.2 vs. 5.0 +/- 0.9 ng/mL/hour) (P < 0.005), did not change excretion of nitric oxide (NO) [NO(2)+ NO(3) (NOx)], ET-1, or catecholamines but reduced excretion of 8-Iso (13.2 +/- 1.4 vs. 9.6 +/- 0.9 ng/24 hours; P < 0.01). Cumulative Na(+) balance and gain in body weight were unaltered by tempol infusion. Tempol prevented a rise in MAP with high salt intake. CONCLUSION: Tempol corrects hypertension without a compensatory sympathoadrenal activation or salt retention. The response is independent of nitric oxide, endothelin, or catecholamines and occurs despite increased PRA. It is accompanied by a reduction in oxidative stress and is maintained during increased salt intake.  相似文献   
43.
报道了β-阻滞剂塞利洛尔的简便制备方法,即以对乙氧基苯胺为原料,经酰胺化,傅克反应,以环氧氯丙烷取代,最后用叔丁胺直接与环氧基反应开环等4步反应制得。比文献五步反应缩短了一步,产物经元素分析、红外光谱、核磁共振谱、质谱等分析确定结构。  相似文献   
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OBJECTIVES: The efficacy of endoscopic treatment of sphincter of Oddi dysfunction (SOD) with endoscopic sphincterotomy (ES) remains controversial. Although some studies have shown a positive impact on patient symptoms after treatment, these reports have been largely qualitative and evaluated on short-term response. The aim of our study was to quantitatively measure the long-term outcomes of endoscopic therapy in patients with SOD. METHODS: Thirty-three patients with suspected SOD underwent selective sphincter of Oddi manometry (SOM) of the biliary and/or pancreatic sphincter. Each patient completed a telephone-based survey measuring symptomatic pain before and after SOM +/- ES. The questioner was blinded to the results of SOM. The patients with normal SOM or SOD but who did not undergo ES served as controls. RESULTS: Of these 33 patients (27 women, mean age 48.7 yr, range 13-74), 19 (57.5%) were found to have SOD (12 biliary, six pancreatic, one both). The average follow-up was 18.1 months (range 7-34). Of the patients with SOD, 17 (89%) underwent ES. At follow-up of the 19 patients undergoing ES, five were taking narcotics for persistent pain, two were taking antidepressants, and 15 identified the endoscopic therapy as the reason for their relief. Of the 14 controls, seven were taking narcotics, seven were taking antidepressants, and two identified the endoscopy as the reason for their relief; some patients were taking both antidepressants and narcotics. CONCLUSIONS: Patients found to have SOD who undergo ES are more likely to be improved on long-term follow-up when compared with patients with suspected SOD but normal manometry without ES. However, almost uniformly, despite ES, patients continue to have pain, which is consistent with most chronic pain disorders and which suggests a multifactorial cause for the pain.  相似文献   
46.
BACKGROUND: The efficacy and safety of the uncoated self-expandable Za metal stent for palliation of malignant distal biliary obstruction was prospectively analyzed. METHODS: Twenty-one patients with unresectable malignant tumors involving mid to distal common bile duct who presented with obstructive jaundice underwent endoscopic implantation of an uncoated self-expandable metal stent. Technical success with stent placement, adverse events, patient survival, duration of stent patency, and device performance were analyzed. RESULTS: Endoscopic biliary stenting was successful in all patients. No adverse events were encountered. The mean follow-up period of the 21 patients was 128 days (range, 3-263): 14 died of progressive disease at mean of 81 days (range, 3-210), 3 remain alive (at days 239, 250, and 263), and 4 were lost to follow-up (at days 90, 91, 92, and 116). The mean duration of stent patency was 249 days. Tumor ingrowth was observed in one patient (5%). Minor technical problems were encountered in 3 patients: 1 proximal deployment, 1 distal deployment, and difficulty associated with the delivery system in 1. CONCLUSIONS: The Za-metal stent provided effective palliation for patients with inoperable malignant biliary tumors. Although minor technical problems were encountered with stent deployment, the overall stent patency, efficacy, and safety profile appear satisfactory.  相似文献   
47.
Diarrhea is a significant problem in patients with acquired immunodeficiency syndrome (AIDS). The aim of this study was to determine octreotide effectiveness in refractory AIDS-associated diarrhea. In a 3-week protocol, 129 patients with a stool weight of >500 g/day despite standard antidiarrheal therapy were randomized to receive octreotide or placebo (3:2 ratio). Octreotide dose was increased 100 μg weekly to a maximum of 300 μg three times a day based on weekly 72-hour stool collections. Subsequently, patients received open-label octreotide at doses of up to 500 μg three times a day. A 30% decrease in stool weight defined response. After 3 weeks, 48% of octreotide- and 39% of placebo-treated patients had responded (P = 0.43). At 300 μg three times a day, 50% of octreotide- and 30.1% of placebo-treated patients responded (P = 0.12). At a baseline stool weight of 1000–2000 g/day, 57% of octreotide- and 25% of placebo-treated patients responded (P = 0.06). Response rates based on CD4 counts, diarrhea duration, body weight, human immunodeficiency virus risk factor, and presence or absence of pathogens showed no benefit of octreotide. Adverse events were more frequent in the octreotide-treated group. In the doses studied, octreotide was not more effective than placebo in patients with refractory AIDS-associated diarrhea. This lack of effectiveness may be attributable to inadequate sample size, doses, and duration of study treatment.  相似文献   
48.
Porter  CD; Parkar  MH; Levinsky  RJ; Collins  MK; Kinnon  C 《Blood》1993,82(7):2196-2202
Chronic granulomatous disease (CGD) is an inherited immunodeficiency resulting from the inability of an individual's phagocytes to produce superoxide anions because of defective NADPH oxidase. The disease may be treated by bone marrow transplantation and as such is a candidate for somatic gene therapy. Two thirds of patients have defects in an X- linked gene (X-CGD) encoding gp91-phox, the large subunit of the membrane cytochrome b-245 component of NADPH oxidase. Epstein-Barr virus-transformed B-cell lines from patients with CGD provide a model system for the disease. We have used retrovirus-mediated expression of gp91-phox to reconstitute functionally NADPH oxidase activity in B-cell lines from three unrelated patients with X-CGD. The protein is glycosylated and membrane associated, and the reconstituted oxidase is appropriately activated via protein kinase C. The kinetics of superoxide production by such reconstituted cells is similar to that of normal B-cell lines. These data show the potential of gene therapy for this disease.  相似文献   
49.
50.
Serum diiodotyrosine (DIT) was measured by radioimmunoassay in healthy subjects patients with thyroid disease and a variety of laboratorty animals. Ninety-two healthy adults had a mean level of 101 ng/100 ml. There was no sex difference in DIT levels but DIT fell with aging. There was no change with short term oral SSKI administration. Athyrotic subjects had measurable but reduced levels (mean = 52 ng/100 ml). Hyperthyroid subjects had levels slightly, but not significantly, higher than controls (mean = 149 ng/100 ml). Treatment of hyperthyroidism was followed by a small but significant fall in DIT levels, but there was no change in DIT levels with thyroid hormone therapy of hypothyroidism. A large species variation in serum DIT levels was found among laboratory animals with mean levels ranging from 17 ng/100 ml in mice to 428 ng/100 ml in dogs.  相似文献   
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