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排序方式: 共有405条查询结果,搜索用时 15 毫秒
1.
A clinical trial on the prevention of catheter-related sepsis using a new hub model. 总被引:8,自引:0,他引:8 下载免费PDF全文
M Segura F Alvarez-Lerma J M Tellado J Jiménez-Ferreres L Oms J Rello T Baró R Sánchez A Morera D Mariscal J Marrugat A Sitges-Serra 《Annals of surgery》1996,223(4):363-369
BACKGROUND: Catheter hub contamination is being increasingly recognized as a source of catheter-related sepsis. The authors have investigated the efficacy of a new hub design in preventing endoluminal catheter contamination and catheter-related sepsis arising at the hub. METHODS: Adult surgical and intensive care patients requiring a subclavian catheter for at least 1 week were randomly assigned to receive catheters with standard connectors (control group, n=73) or equipped with a new hub model (new hub group, n=78). Skin, catheter tip, and hub cultures were performed at the time the catheter was withdrawn because therapy was terminated or because of suspicion of sepsis, in which case peripheral blood cultures were taken. RESULTS: Of the 151 patients included, 15 (10%) developed catheter-related sepsis. Catheters were more often withdrawn because suspicion of infection in the control group (42 vs. 19%, p<0.005). Catheter sepsis rate was higher in the control group (16 vs. 4%, p<0.01) because of the low rate of catheter sepsis arising at the hub observed in the new hub group (1 vs. 11%, p<0.01). The prevalence of culture-positive catheter hubs without associated bacteremia (colonization) was higher in the control group (18 vs. 5%, P<0.03). CONCLUSIONS: A new catheter hub has proved to be useful in preventing endoluminal bacterial colonization and catheter-related sepsis in subclavian lines inserted for a mean of 2 weeks. 相似文献
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Epidermal growth factor directly stimulates steroidogenesis in primary cultures of porcine Leydig cells: actions and sites of action 总被引:7,自引:0,他引:7
The actions and the mechanisms of action of epidermal growth factor (EGF) in testicular steroidogenesis were investigated using a model of primary culture of purified porcine Leydig cells from immature intact animals. EGF decreased (1.7-fold) human CG (hCG)-induced dehydroepiandrosterone (DHEA) accumulation in the medium whereas it enhanced (2.5-fold) that of testosterone. The maximal and half-maximal effects on both DHEA and testosterone secretions were observed at similar concentrations which were, respectively, 3 (5 x 10(-10) M) and 0.7 (11 x 10(-11) M) ng/ml EGF, after 72-h treatment. EGF effect on DHEA and testosterone secretion was similarly observed whether the cells were acutely (3 h) stimulated with hCG (1 ng/ml) or with 8-bromo-cAMP (10(-3) M). To further localize the steroidogenic biochemical steps affected by EGF, the growth factor action on steroidogenic enzyme activities was investigated. EGF increased delta 5 steroid intermediate (i.e. pregnenolone and DHEA) formation [evaluated in the presence of 10(-5) M of WIN 24540, an inhibitor of 3 beta-hydroxysteroid dehydrogenase/iosomerase (3 beta-HSDI) activity]. However, this stimulation was observed in cells when acutely (3 h) stimulated with hCG (0.01-1 ng/ml) but not when incubated with 22R-hydroxycholesterol (0.01-10 micrograms/ml). Such findings indicate that EGF did not affect cholesterol side chain cleavage cytochrome P450 activity but probably increased cholesterol substrate availability for this enzyme in the inner mitochondria. Moreover, EGF significantly (P less than 0.001) increased delta 5 steroid intermediate (i.e. pregnenolone and DHEA) but not delta 4 steroid intermediate (i.e. progesterone and androstenedione) conversion into testosterone, indicating that EGF enhances 3 beta-HSDI activity. Such effects of EGF are directly exerted on Leydig cells since EGF receptors (Kd = 16 x 10(-11) M) are present in primary cultures of purified porcine Leydig cells. Together, the present findings show that in Leydig cells from intact animals, EGF enhances the gonadotropin action on testosterone formation through an increase in the availability of cholesterol substrate in the mitochondria as well as an increase in the activity of 3 beta-HSDI. 相似文献
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Francisco Robaina Bernardino Clavo Luis Catal Miguel . Carams Jesús Morera 《Neuromodulation》2004,7(1):26-31
The effect of spinal cord stimulation (SCS) on cerebral blood flow (CBF) has, in the past, been evaluated by semiquantitative techniques, but has not been used to treat CBF diseases. The aim of this study was to assess the effect of cervical SCS on regional blood flow by both semiquantitative and quantitative methods. Thirty‐five patients with cervical SCS‐implanted devices were enrolled. The following parameters were measured before and after cervical SCS: systolic and diastolic velocity (cm/s) in the middle cerebral artery (MCA) by transcranial Doppler (TCD) and volume blood flow quantification (ml/min) in the common carotid artery (CCA) by color Doppler. During cervical SCS there was a significant and bilateral increase in systolic (21%) and diastolic (26%) velocity in the MCA and in CCA blood flow (50%). We conclude that cervical SCS increases blood flow in the middle cerebral artery and common carotid artery. The consistent increase supports the potential usefulness of cervical SCS as an adjuvant treatment for cerebral blood flow diseases. 相似文献
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F. Deulofeu J. M. Nava F. Bella C. Martí M. A. Morera B. Font D. Fontanals J. Lite J. Garau A. Calderón M. T. Coll S. Uriz V. Pineda 《European journal of clinical microbiology & infectious diseases》1994,13(8):633-638
The incidence and characteristics of invasiveHaemophilus influenzae disease were studied in 43 adult patients admitted to the acute care hospitals in El Vallés County (Barcelona, Spain) between January 1987 and June 1992. The annual incidence ofHaemophilus influenzae disease was 1.2 per 100,000 inhabitants. Pneumonia occurred in 24 patients, meningitis in five, intraabdominal infections in three, obstetric infections in two, epiglottitis in two and cellulitis in one. In six patients the source of infection was unknown. Ten (23 %) of the infections were hospital acquired. Underlying conditions were diagnosed in 30 (70 %) patients. NontypeableHaemophilus influenzae strains predominated in all adult age groups. Sixty-one percent of type b and 34 % of nontypeable strains were ampicillin resistant (p=0.08). Multiple antibiotic resistance was also high among type b (53 %) and nontypeable (18 %) strains. The mortality rate was significantly higher in patients with pneumonia, bactaeremia from an unidentified focus or shock at presentation. 相似文献
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Vicente Sabater Marco Begoña Escutia Muñoz Arturo Morera Faet Manuel Mata Roig Rafael Botella Estrada 《Journal of cutaneous pathology》2013,40(3):330-335
Spitz nevus is a benign melanocytic proliferation that shows relatively characteristic clinicopathologic features. Despite this, Spitz nevus is clinically confused with many other lesions, and histopathologically it is sometimes difficult to distinguish it from melanoma. However, Spitz nevus rarely causes differential diagnostic problems with granulomatous dermatitis. This article describes an 8‐year‐old girl who presented with a nodule on her right arm, a clinical appearance of a pyogenic granuloma. Histopathologically, there was a dermal lesion composed of aggregates of large epithelioid cells surrounded by a heavy inflammatory infiltrate, mimicking a sarcoid‐like granulomatous dermatitis. Immunohistochemistry showed epithelioid cells with strong nuclear and cytoplasmic staining with S‐100 protein, thus establishing the diagnosis of a melanocytic tumor. The heavy T‐cell lymphocytic infiltrate that accompanies the large epithelioid cells caused its granulomatous appearance. Molecular assessment showed H27H mutation in the HRAS gene. We suggest the term ‘pseudogranulomatous’ for this variant of Spitz nevus because it indicates that the lesion is not authentically granulomatous and simply mimics a granulomatous dermatitis. 相似文献
9.
Objectives: Despite prevailing beliefs about the potential benefits and harmfulness of mindfulness for people who hear voices, there is a paucity of research into staff and service user views. Q-methodology was used to explore views about mindfulness groups for voice-hearers. Method: Opportunistic sampling of mental healthcare staff (N?=?14) and service users with psychosis (N?=?17). Both samples were analysed using principle components factor analysis to identify the range of attitudes held by staff and service users. Results: Staff participants were particularly knowledgeable and interested in mindfulness. A single staff consensus factor was found suggesting mindfulness is helpful, and not harmful for mental health, but uncertainty surrounded its usefulness for voice-hearers. Service users held four distinct attitudes: (i) mindfulness helps to calm a racing mind; (ii) mindfulness helps to manage stress; (iii) mindfulness improves well-being, and does not alter the brain, reality beliefs, or cause madness; and (iv) mindfulness helps with managing thoughts, fostering acceptance, and is acceptable when delivered in a group format. Conclusions: Staff viewed mindfulness groups for psychosis as helpful, not harmful, but were uncertain about their utility. Consistent with previous research, service users viewed mindfulness groups as useful to promote well-being and reduce distress for individuals experiencing psychosis. 相似文献
10.
Maria-Teresa Coll María-Socorro Uriz Valentí Pineda Dionisia Fontanals Feliu Bella Juan M. Nava Francesc Deulofeu Maria-Antnia Morera Carme Martí Josep Lite Javier Garau Bernat Font 《The Journal of infection》1994,29(3)
A prospective study was made of all patients with normal CSF counts and positive cultures for Neisseria meningitidis diagnosed in “El Vallés” County, Barcelona between January 1987 and December 1990. Meningococcal meningitis was documented in 82 patients, eight of whom (seven children, five boys and two girls with a mean age of 5·6 ± 3·3 years, and a 69-year-old male patient) had no apparent CSF abnormalities in the initial lumbar puncture. At the time of admission all patients had fever (mean 39·1 °C) of 10·8 ± 5·6 hour duration and petechial rash which had been present for a mean of 3·6 ± 3·3 hours. Signs of meningeal irritation were not found. A 4-month-old infant with symptoms of circulatory collapse, intracranial hypertension and impairment of consciousness subsequently died of septicemia in 48 hours. Group B N. meningitidis was isolated in six cases (reduced penicillin-susceptibility in two cases) and group C N. meningitidis in the remaining two (reduced penicillin-susceptibility in one case). Patients without pleocytosis did not differ in a statistically significant fashion from the patients with high pleocytosis in the duration of temperature, and petechial rash, leukopenia, positive blood culture and fatal outcome. 相似文献