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81.
Giorgio Nanni Federica Majorani Anna Maria Bassi Claudio Canepa Giuseppe Maloberti Anna Casu 《Experimental and toxicologic pathology》2002,54(1):43-50
The content of dolichol, an isoprenoid present in all biological membranes, was determined in isolated sinusoidal liver cells after treatment of rats for 2 and 4 months with a low dosage of the hepatotoxin thioacetamide. The significant decrease in dolichol observed in hepatocytes after 2 months might be explained by peroxidation of the isoprenoid. At the same time point, retinol was retained, and decreased only after 4 months of treatment. After 4 months of treatment therefore both lipids decreased. In a subfraction of hepatic stellate cells, Ito-1 cells, the main storage site of vitamin A, dolichol decreased significantly only after 4 months. A remarkable difference from hepatocytes is that in Ito-1 cells retinol content significantly decreased after 2 months of treatment. In another subfraction, Ito-2 cells, the content of the two isoprenoids decreased in parallel. This heterogeneous subfraction might represent those transitional hepatic stellate cells that, while losing retinol, are in the process of differentiating into myofibroblasts secreting extracellular matrix components. In Kupffer cells and sinusoidal endothelial cells, impairment of dolichol might be observed later, only after 4 months of treatment, while retinol decreases uniformly over time. Starting after two months of treatment, the decrease of dolichol and the increase of retinol in hepatocytes, at the same time as retinol decreases in hepatic stellate cells, might be taken as an early index of incipient liver injury due to thioacetamide. This hypothesis is discussed with regard to a role of dolichol in the modulation of membrane fluidity for intracellular and intercellular retinol transport. 相似文献
82.
Adriano Rizzi Gaetano Rocco Mario Robustellini Gerolamo Rossi Claudio Della Pona Giuseppe Vertemati 《World journal of surgery》1997,21(5):488-491
n
= 8), multidrug resistance
or noncompliance to the medical treatment (
n
= 11),
parenchymal sequelae (
n
= 3), suspected cancer
(
n
= 5), and for the correction of postpneumonectomy
bronchopleural fistula and empyema (
n
= 1). On
admission, eight patients presented with sputum positivity (28.6%).
Similar to previous series, tubercular predilection for upper lobes was
confirmed (21/28, 75%); accordingly, upper lobectomy through an
extrapleural approach was the most common procedure (16/28, 57.1%).
Atypical segmental resections or segmentectomies were performed in
seven patients (25%), whereas a bilobectomy was necessary in another
three patients (10.7%) and a completion pneumonectomy in one (3.6%).
Additional procedures were an open-window thoracostomy with
transpericardial closure of the main bronchus and a tailored
thoracoplasty. No operative mortality was reported. Healing was
achieved in 26 patients (93%). Bleeding, either from the chest wall or
hilar dissection, was the only reported intraoperative complication.
Median blood loss, inclusive of early postoperative collections from
chest tubes, reached 1330 ml (range 100–3700 ml). Major postoperative
complications included recurrent disease (2/28, 7%) in sputum-positive
patients and segmental pulmonary embolism (3.5%). Causes of minor
morbidity were air leaks resulting in residual space undergoing
spontaneous resolution (18%), wound breakdown (14%), and, fever
(11%). This limited series confirms the therapeutic value of the
surgical treatment of postprimary tuberculosis, provided that correct
indications, adequate pre- and postoperative medical coverage, and
meticulous technique are applied. 相似文献
83.
Bone mineral content (BMC) and testosterone levels were evaluated and compared in 10 hypogonadal males and 10 normal, age-matched controls. In 6 of the subjects an investigation was also carried out into the effects of testosterone administration on lumbar BMC, calcitonin (CT) response to hypercalcaemia, osteocalcin (BGP) and the fasting urinary calcium/creatinine and hydroxyproline/creatinine ratios. Our results confirm that male hypogonadism is characterized by a low BMC and that testosterone administration is able to improve this parameter and to increase both basal BGP and CT response to hypercalcaemia. Testosterone therefore probably acts on bone tissue through both a direct action on osteoblast cells and an improvement in CT secretion. 相似文献
84.
Non-invasive treatment for retained common bile duct stones in patients with T tube in situ: saline washout after intravenous ceruletide 总被引:1,自引:0,他引:1
The combination of ceruletide-induced relaxation of the sphincter of Oddi plus flushing with saline has recently been proposed as a novel procedure for the treatment of residual common bile duct (CBD) stones. In this study we have administered intravenous ceruletide (2 ng kg-1 body weight min-1 for 1 h) plus intraductal saline (800-3000 ml, infused at a rate that kept biliary pressure below 30 cmH2O) to a group of 14 patients. The treatment induced the passage of residual stones in 11 subjects (79 per cent) with complete clearance in 7 (50 per cent). The majority of the cleared concretions (11/15) had a diameter less than 10 mm. No severe side-effects were recorded during the treatment. Four of the seven subjects who exhibited incomplete CBD clearance underwent a short cycle of mono-octanoin administration in order to reduce the size of residual radiolucent stones. This course of treatment was followed by another attempt with intravenous ceruletide and saline washout which gave a successful response in an additional three cases. These data indicate that the combination of ceruletide and flushing is a safe and inexpensive method for treatment of residual stones. The procedure is feasible for both radiolucent and radio-opaque stones and is mainly eligible for small concretions of diameter less than 10 mm. Larger (greater than 10 mm) radiolucent stones may be partially dissolved with mono-octanoin and then eliminated by the washout technique. 相似文献
85.
86.
Distribution of paresthesias in Carpal Tunnel Syndrome reflects the degree of nerve damage at wrist.
Pietro Caliandro Giuseppe La Torre Irene Aprile Costanza Pazzaglia Irene Commodari Pietro Tonali Luca Padua 《Clinical neurophysiology》2006,117(1):228-231
OBJECTIVE: To verify whether the distribution of paresthesias in patients with Carpal Tunnel Syndrome (CTS) is related to the degree of the neurophysiological involvement. METHODS: We performed a cross-sectional study and retrospectively evaluated 163 patients who referred to our electromyography lab and to which a clinical and electrophysiological diagnosis of CTS was made. We divided the patients into two groups: (1) patients complaining of paresthesias at the hand as a whole and (2) patients with paresthesias in the territory of the median nerve. We referred to the distribution of paresthesias at the hand as GLOVE and to the distribution in the territory of the median nerve as MEDIAN. We compared the neurophysiological impairment in GLOVE and MEDIAN distributions. Moreover, we performed multiple regression analysis to evaluate which clinical-neurophysiological variables determined GLOVE and MEDIAN distribution. RESULTS: In our sample, 70.4% of patients had GLOVE distribution and 29.6% of patients MEDIAN distribution. The risk of presenting MEDIAN distribution increases about twice (OR = 2.07; 95% IC: 1.51-2.83) for each unitary increment of neurophysiological class. CONCLUSIONS: The distribution of paresthesias reflects the degree of nerve damage at wrist; patients suffering of SEV/EXT CTS present MEDIAN distribution. SIGNIFICANCE: Our data have important clinical implications because they strongly suggest that we have to consider the possibility of a severe neurophysiological involvement of the median nerve at wrist in patients complaining of MEDIAN distribution. 相似文献
87.
目的:介绍一种快速定量检测HBV DNA的方法及临床初步应用。方法:对40例乙型肝炎病毒表面抗原阳性的慢性乙型肝炎患者共79份血清标本,采用Digene第二代杂交捕获试验(Hybrid Capture Ⅱ,HCⅡ,v2.0)定量检测HBV DNA,并与分枝链DNA信号扩增试验(bDNA,v1.0)作比较。结果:79份HBsAg阳性血清中,HCⅡ检出HBV DNA57份(72.2%),bDNA法为45份(57%),HCⅡ敏感性略高于bDNA法;2种方法定量检测HBV DNA的符合率为85.9%,相关性良好(r=0.95);19例抗病毒治疗乙肝患者,治疗后平均HBV DNA载量下降2(Log10)数量级,6例发生e抗原血清转换的患者平均HBV DNA载量下降3(Log10)数量级以上,且HBV DNA阴转早于e抗原血清转换。结论:HCⅡ比bDNA更为简便、经济、快速,可用于临床HBV DNA水平的定量检测、监控及抗病毒药物的筛选、考核。 相似文献
88.
Functional signatures of protective antiviral T-cell immunity in human virus infections 总被引:9,自引:0,他引:9
Alexandre Harari Valérie Dutoit Cristina Cellerai Pierre-Alexandre Bart Renaud A. Du Pasquier & Giuseppe Pantaleo 《Immunological reviews》2006,211(1):236-254
Summary: The most common human viruses have different abilities to establish persistent chronic infection. Virus‐specific T‐cell responses are critical in the control of virus replication and in the prevention of disease in chronic infection. A large number of phenotypic markers and a series of functions have been used to characterize virus‐specific CD4+ and CD8+ T‐cell responses, and these studies have shown great phenotypic and functional heterogeneity of the T‐cell responses against different viruses. The heterogeneity of the T‐cell response has been proposed to be specific to each virus. However, over the past 2 years, several studies have provided evidence that the phenotypic and functional heterogeneity of CD4+ and CD8+ T‐cell responses is predominantly regulated by the levels of antigen load. The levels of antigen load modulate the phenotypic and functional patterns of the T‐cell response within the same virus infection. Furthermore, the functional characterization of virus‐specific CD4+ and CD8+ T‐cell responses has identified signatures of protective antiviral immunity. Polyfunctional, i.e. interleukin‐2 and interferon‐γ (IFN‐γ) secretion and proliferation, and not monofunctional, i.e. IFN‐γ secretion, CD4+ and CD8+ T‐cell responses represent correlates of protective antiviral immunity in chronic virus infections. 相似文献
89.
Treatment of Status Epilepticus in Adults: Guidelines of the Italian League Against Epilepsy 总被引:2,自引:1,他引:1
Fabio Minicucci †Giancarlo Muscas ‡Emilio Perucca §Giuseppe Capovilla Federico Vigevano ¶Paolo Tinuper 《Epilepsia》2006,47(S5):9-15
Summary: Status epilepticus (SE) is a medical emergency which can lead to significant morbidity and mortality and requires prompt diagnosis and treatment. SE is differentiated into generalized or partial SE on the basis of its electro-clinical manifestations. The guidelines for the management of SE produced by the Italian League against Epilepsy also distinguish three different stages of SE (initial, established and refractory), based on time elapsed since the onset of the condition and responsiveness to previously administered drugs. Treatment should be started as soon as possible, particularly in generalized convulsive SE, and should include general support measures, drugs to suppress epileptic activity and, whenever possible, treatments aimed at relieving the underlying (causative) condition. Benzodiazepines are the first line antiepileptic agents, and i.v. lorazepam is generally preferred because it is associated with a lower risk of early relapses. If benzodiazepines fail to control seizures, i.v. phenytoin is usually indicated, though i.v. phenobarbital or i.v. valproate may also be considered. Refractory SE requires admission to an intensive care unit (ICU) to allow adequate monitoring and support of respiratory, metabolic and hemodynamic functions and cerebral electrical activity. In refractory SE, general anesthesia may be required. Propofol and thiopental represent first line agents in this setting, after careful assessment of potential risks and benefits. 相似文献
90.
The steady-state density and the turnover rates of D1-dopamine receptors were investigated in the striatum, nucleus accumbens, substantia nigra, and retina of adult (3-month-old) and aged (23-month-old) rats. The turnover rates were measured by monitoring the repopulation kinetics of D1-dopamine receptors labeled with [3H]-SCH 23390 after the irreversible inactivation induced by a single dose of N-ethoxycarbonyl-2-ethoxy-1,2-dihydroquinoline (EEDQ, 10 mg/kg, s.c.). In all the neural tissues examined, the repopulation of D1 dopamine receptors could be adequately described by a theoretical model that assumes a constant rate of receptor production (i.e. zero order) and a rate of degradation that is dependent on the receptor density at any time (i.e. first order). The results obtained indicate that the reduction in the density of D1-dopamine receptors in the striatum, nucleus accumbens and substantia nigra of aged rats is the result of a larger decrease in the receptor production rate (−44 to −60%) than in the receptor degradation rate (−21 to −46%). By contrast, the production rate of D1-dopamine receptors in the retina of aged rats remains unchanged, whilst the degradation rate is reduced by 25%. This results in an age-related increase in the density of D1-dopamine receptors in the rat retina. 相似文献