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991.
Angiotensin-II (Ang-II) has inflammatory activity and is involved in different diseases associated with the cardiovascular system. This study has evaluated the effect of boldine (B), and two phenanthrene alkaloids semisynthesized by us, secoboldine (SB) and boldine methine (BM), on Ang-II-induced neutrophil recruitment. Intraperitoneal administration of 1 nM Ang-II induced significant neutrophil accumulation, which was maximal at 4-8 h. BM inhibited neutrophil infiltration into the peritoneal cavity at 4 h and 8 h by 73% and 77%, respectively, SB at 8 h by 55%, and B had no effect on this response. Although BM inhibited the release of cytokine-inducible neutrophil chemoattractant/keratinocyte-derived chemokine, macrophage inflammatory protein-2 (MIP-2), and platelet-activating factor (PAF) elicited by Ang-II, SB only reduced the release of MIP-2 after 4 h of its administration. Sixty-minute superfusion of the rat mesentery with 1 nM Ang-II induced a significant increase in the leukocyte-endothelial cell interactions and P-selectin up-regulation, which were inhibited by 1 microM BM and SB. The generation of reactive oxygen species (ROS) in endothelial cells stimulated with Ang-II was inhibited significantly by the three alkaloids tested. BM also diminished Ang-II-induced interleukin-8 release from endothelial cells and blocked the PAF receptor on human neutrophils (concentration of the compound needed to produce 50% inhibition value: 28.2 microM). Therefore, BM is a potent inhibitor of Ang-II-induced neutrophil accumulation in vivo. This effect appears to be mediated through inhibition of CXC chemokine and PAF release, ROS scavenging activity, and blockade of the PAF receptor. Thus, it may have potential therapeutic interest for the control of neutrophil recruitment that occurs in inflammation associated with elevated levels of Ang-II.  相似文献   
992.
We report the case of a 17-year-old male with a testicular tumor and high serum levels of -fetoprotein. The patient was treated with surgery followed by combination chemotherapy with bleomycin, etoposide, and cisplatin. Histologic examination showed features of a mixed germ cell tumor composed of mature teratoma, immature teratoma, embryonal carcinoma, yolk sac tumor, and polyembryoma. He is currently well, and his serum levels of -fetoprotein have been normal more than 5 months after treatment. His brother, aged 17 years at the time, had a similar tumor removed from the right testicle 5 years previously.  相似文献   
993.
The efficacy of Virkon S, a commercial disinfectant as a virucidal spray against human enterovirus 71 (HEV71), the causative agent of the fatal form of hand, foot and mouth disease was examined. At least one log10 reduction of HEV71 titer was achieved when one spray of Virkon (1% or 2%) with ten minutes of contact time was applied. The infectivity was completely lost when four sprays of 1% or 2% Virkon were applied, suggesting that at least four sprays of 1% Virkon to the surface bound HEV71 was necessary to completely inactivate the virus. These findings suggest that Virkon S at the proper concentration is suitable to be used as an effective and easy to use disinfectant against HEV71.  相似文献   
994.
This is a quasi-experimental study that aimed to compare the use of alcohol and traditional methods for newborn's cord care with a no-treatment approach, natural drying. The study also aimed to identify the factors associated with the occurrence of cord infection and time of cord separation. A convenient sample of 70 women with vaginal delivery, full-term and healthy babies was selected from postpartum departments of two university hospitals in Alexandria and Minia. A specially designed interview schedule was developed and utilized to collect data. Swabs were taken from the newborns' umbilical stumps on zero and 3rd day of birth to detect bacterial colonization. Follow-up was carried-out at home to assess methods used for cord care, babies' hygiene, cord infection and time of cord separation. The study revealed that traditional methods of cord care were used by women with higher mean age (30.8 +/- 7.8 years), from Minia (100%) or rural areas (71.4%), while alcohol and natural drying were used by women with lower mean age (27.7 +/- 4.8 and 24.8 +/- 6.5 years) respectively, from Alexandria (76% and 100%) respectively or urban areas (56% and 64.7%) respectively. Alcohol was used for male babies (76%), while traditional methods and natural drying were used for female babies (71.4% & 64.7%) respectively. Incidence of cord infection was significantly lower among natural drying group (35.3%), and no signs of systemic infection were observed among them. Rate of increase of bacterial colonization (from 0-3rd day of birth) was significantly higher in alcohol group (44%). It was relatively similar with presence or absence of cord infection (33.3 & 32.1) respectively. Mean time of cord separation was longer among alcohol group (6.4 +/- 2.4 days), as compared with natural drying group (4.7 +/- 1.9 days) and traditional methods group (3.4 +/- 0.7 days). Bathing baby while cord was attached was carried-out by all women of alcohol and natural drying groups, compared to only 28.6% of traditional methods group. Breast-feeding was significantly related to less incidence of cord infection (P= 0.008) and shorter time of cord separation (P= 0.002). Incidence of cord infection was significantly related to using cloth diaper (P= 0.015), using dry method for skin care (X(2) 2= 7.2917), giving tub bath (X(1)2 = 4.1788) and delaying the bath to the 7th day of birth (P= 0.050). Time of cord separation was significantly shorter with closed cord dressing (X(2)2= 20.4028), in Minia, during spring, among male babies (X(2)2= 15.0352), and in rural areas (X(2)2 = 9.7608). It was significantly longer with bathing the baby while cord was attached (X(2)2 = 27.9354), giving 2-3 baths/week or delaying the bath to the 7th day of birth (P= 0.049) and with using cloth diaper (P= 0.0467). So, moving from an intervention to a non- intervention, particularly in a healthy population should be applied to the healthy naturalistic approach to care advocated in nursing. Also, only through continuing efforts done to examine our assumptions about historic health care routines, will we be able to demonstrate evidence-based practice and to advance nursing care.  相似文献   
995.
996.
When fundoplication fails: redo?   总被引:8,自引:0,他引:8       下载免费PDF全文
OBJECTIVE: The largest series in the literature dealing with redo fundoplication was presented and published in 1999 and included 100 patients. Herein we update this initial series of 100, with 207 additional patients who have undergone redo fundoplication (n = 307). SUMMARY BACKGROUND DATA: Increasing numbers of patients are failing esophagogastric fundoplication and requiring redo procedures. Data regarding the nature of these failures have been scant. METHODS: Data on all patients undergoing foregut surgery are collected prospectively. Between 1991 and 2004, 307 patients underwent redo fundoplication for the management of anatomic complications or recurrent GERD. Statistical analysis was performed with multiple chi2 and Mann-Whitney U analyses, as well as ANOVA. RESULTS: Between 1991 and 2004, 1892 patients underwent primary fundoplication for GERD (1734) or paraesophageal hernia (158). Of these, 54 required redo fundoplication (2.8%). The majority of failures (73%) were managed within 2 years of the initial operation (P = 0.0001). The mechanism of failure was transdiaphragmatic wrap herniation in 33 of 54 (61%). In the 231 patients who underwent fundoplication elsewhere, 109 had transdiaphragmatic herniation (47%, P = NS). In this group of 285 patients, 22 (8%) required another redo (P = NS). The majority of the procedures were initiated laparoscopically (240/307, 78%), with 20 converted (8%). Overall mortality was 0.3%. CONCLUSIONS: Failure of fundoplication is unusual in experienced hands. Most are managed within 2 years of the initial operation. Wrap herniation has now become the most common mechanism of failure requiring redo. Redo fundoplication was successful in 93% of patients, and most could be safely handled laparoscopically.  相似文献   
997.
Long term use of immunosuppressants impacts the cardiovascular system and increases the risk of infection and malignancy. To effectively reduce immunosuppression in a transplant recipient a tool is needed to directly monitor the level of immune function. The Cylex(R) Immune Cell Function Assay, approved by the FDA for the assessment of cell-mediated immunity, shows promise as an objective measure of a transplant recipient's immune function. In a blinded retrospective study, the immune function was compared to clinical courses and histological examinations of biopsies of 20 small bowel transplant recipients during periods of immunosuppressant tapering. Eight patients with no major adverse events or changes of immunosuppressive therapy had moderate to low immune function and were categorized as immunologically and clinically stable. Twelve patients displaying strong immune responses were immunologically and clinically volatile requiring addition of steroids and or OKT3. Results validate the clinical utility of the Cylex Immune Cell Function Assay as an objective tool for assessing immune function. By evaluating immune function, physicians now can identify those patients who are candidates for minimization of immunosuppressant therapy, manage the timing and rate of immunosuppressant weaning and be forewarned of increased patient risk.  相似文献   
998.
Mucosal nerve sheath tumors have been well described in the gastrointestinal tract and other mucosal sites. In a series of mucosal biopsies, we have encountered a distinct subset of mucosal peripheral nerve sheath tumors characterized by small epithelioid cells and a benign clinical course. Such epithelioid nerve sheath tumors have been observed as a component of a larger study of colorectal "schwannomas," but herein we describe them in detail. A series of 7 of these lesions detected on mucosal biopsies (6 colonic, 1 bladder) was received by a single large institution in consultation material. The histologic and clinicopathologic features of the cases were reviewed. The mean age at presentation was 58.6 years with a slight female predominance (4 females, 3 males). Five of the colonic lesions were from the left colon and one from the right colon. The bladder biopsy was from the bladder neck. All of the colonic lesions were discovered as small (0.2-1.0 cm) polyps during the time of colonoscopy (3 at the time of routine screening, 2 for the workup of occult blood in the stool). The bladder neck mass was seen on bladder ultrasound after the patient presented with vaginal bleeding. None of the patients had a known history of neurofibromatosis. Histologically, the lesions showed an infiltrative growth pattern and were composed of spindled to predominantly epithelioid cells arranged in nests and whorls. The epicenters of the lesions were located in the lamina propria and extended to the superficial submucosa. The proliferating cells had uniform round to oval nuclei with frequent intranuclear pseudoinclusions and eosinophilic fibrillary cytoplasm. No mitoses were seen. All lesions expressed diffuse S-100 protein, and 3 of 5 lesions stained showed CD34 labeling in supporting cells. All were negative for CD117. All 5 lesions tested were negative for calretenin, while SM31 showed no intralesional neuraxons. One lesion was stained for epithelial membrane antigen and was negative. One lesion was associated with superficial mucosal erosion, and 1 had an inflammatory infiltrate predominantly composed of eosinophils. On follow-up of 5 patients, none has had any symptoms or recurrence of disease. Mucosal epithelioid nerve sheath tumors are a rare entity characterized by prominent epithelioid round to oval cells with an infiltrative growth pattern. These lesions are often discovered incidentally and have a benign clinical course.  相似文献   
999.
OBJECTIVE: Spontaneous intracranial haemorrhage constitutes 18-40% of all stroke cases. Indications for cerebral angiography to find underlying potentially treatable vascular abnormalities are not clear. This study determined which intracranial haemorrhage patients need cerebral angiography by correlating computed tomography (CT) findings, age and hypertension history with cerebral angiography findings. METHODS: A total of 54 patients (8-79 years) with intracranial haemorrhage who underwent both CT examination and six-vessel cerebral angiography were studied over a 2-year period. Cerebral angiography was repeated within 6 weeks if the first angiogram was negative. RESULTS: Angiography detected vascular lesions in 50% of cases (aneurysm 38.9% and arteriovenous malformation, AVM, 11.1%). In the aneurysm group, angiographic yield was 34.3% whereas in the AVM group, it was 37.9%. Subarachnoid haemorrhage (SAH) combined with other types of haemorrhage (such as intracerebral haemorrhage, ICH) was not significantly correlated with the likelihood of finding a vascular lesion, both aneurysm and AVM (p = 0.157). Age less than 50 years had significant correlation (p = 0.021) in the AVM group as well as in the aneurysm group (p < 0.001). A history of hypertension was associated with both aneurysm (p = 0.039) and AVM (p = 0.008). No patients with deep intracerebral haematoma had vascular lesions. The presence of an intravascular haemorrhage (IVH) had significant correlation with aneurysm (p = 0.008) but not AVM. There was no significant difference in mean age between patients with and without a vascular lesion (p = 0.134). CONCLUSION: Cerebral angiography is justified in patients with ICH accompanied by pure SAH (p = 0.001). Other factors associated with finding a vascular lesion were a history of hypertension and the presence of IVH. Diagnostic cerebral angiography is indicated for patients with ICH and SAH and IVH with a history of hypertension, regardless of age.  相似文献   
1000.
1. Oxidative stress is recognized as a major contributing factor for the development of late complications of diabetes. 2. Tea contains polyphenolic compounds (catechins), which have many important biological properties, including strong anti-oxidant activity. 3. The present study was undertaken to evaluate the effect of tea catechins (epigallocatechin gallate (EGCG), epigallocatechin (EGC), epicatechin gallate (ECG) and epicatechin (EC)) on markers of oxidative stress (malondialdehyde (MDA), reduced glutathione (GSH) and membrane -SH group) in erythrocytes from type 2 diabetics. 4. Oxidative stress was induced in normal and type 2 diabetic erythrocytes by incubating with tert-butyl hydroperoxide (t-BHP). 5. Diabetic erythrocytes have higher MDA and decreased GSH and membrane -SH groups compared with normal erythrocytes. 6. Our results show that tea catechins protect erythrocytes from t-BHP-induced oxidative stress, the effect being more pronounced in diabetic erythrocytes. The relative effectiveness of individual catechins are in the order of EGCG>ECG>EGC>EC. 7. We hypothesise that a higher intake of catechin-rich food by diabetic patients may provide some protection against the development of long-term complications of diabetes.  相似文献   
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