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101.
OBJECTIVE: We evaluated the influence of chronic blockade of the renin-angiotensin system on hypertension induced by long-term thyroxin (T4) administration. To this end, we determined the effects of chronic treatment with captopril on blood pressure, cardiac hypertrophy and other renal and metabolic variables of hypertensive hyperthyroid rats. METHODS: T4 was administered s.c. at 0.38 mumol/kg per day and captopril was given in the drinking water (1.38 mmol/l). Both treatments were maintained for 6 weeks. Control rats received tap water. After the treatment period, the rats were placed in metabolic cages. Later, blood pressure was measured in conscious rats by intra-arterial determination. RESULTS: T4-treated rats showed an increased mean arterial pressure (MAP) whereas, in rats treated with T4 plus captopril, MAP was similar to that of the control group. Captopril did not affect the increased heart rate or ventricular weight/body weight ratio of hyperthyroid rats, but it improved the reduced creatinine clearance of these animals. CONCLUSIONS: The elevation in blood pressure produced by long-term T4 administration was prevented by chronic blockade of the renin-angiotensin system. Captopril improved the renal function of hyperthyroid rats, but did not affect the relative cardiac hypertrophy of these animals.  相似文献   
102.
BACKGROUND: Although numerous reports have described interventions designed to influence antibiotic utilization, to our knowledge none have been evaluated in a randomized study. METHODS: Adult inpatients receiving 1 or more of 10 designated parenteral antibiotics for 3 or more days during a 3-month period were randomized to an intervention (n = 141) and a control (n = 111) group using an unblocked, computer-generated random number table. Obstetric patients and those seen in infectious disease consultation were excluded. The intervention group received antibiotic-related suggestions from a team consisting of an infectious disease fellow and a clinical pharmacist. Both groups were evaluated for clinical and microbiological outcomes as well as antibiotic utilization via prospective chart reviews and analysis of the hospital's administrative database. RESULTS: Sixty-two (49%) of the intervention group patients received a total of 74 suggestions. Sixty-three (84%) of these suggestions were implemented; the majority involved changes in antibiotic choice, dosing regimen, or route of administration. Per patient antibiotic charges were nearly $400 less in the intervention group vs controls (P = .05). Almost all the savings were related to lower intravenous antibiotic charges. Clinical and microbiological response, antibiotic-associated toxic effects, in-hospital mortality, and readmission rates were similar for both groups. Multiple linear regression analysis identified randomization to the intervention group and female sex as the sole predictors of lower antibiotic charges. There was a trend toward a shorter length of stay for the intervention group (20 vs 24.7 days, P = .11). CONCLUSIONS: This is the first randomized study to evaluate whether antibiotic choices can be influenced in a cost-effective fashion without sacrificing patient safety. We demonstrate that 50% of patients initially treated with expensive parenteral antibiotics can have their regimens refined after 3 days of therapy and that these modifications result in good clinical outcomes with a substantial reduction in antibiotic expense.  相似文献   
103.
104.
We studied the bioaccumulation and the toxic effects of Cu on survival, number of eggs and eggmasses laying, embryo development, growth, and food consumption in an Indian pond snail, Lymnaea luteola L. exposed for 7 weeks. Copper caused loss of chemoreception, locomotion and inhibited food consumption significantly during 7 weeks of exposure. Food consumption in Cu exposed snails significantly decreased and at 56 and 100 μg L(-1), snail stopped feeding activity. Mean number of eggmasses or eggs significantly decreased in Cu concentrations during the 7 week study. The percentage hatching decreased in Cu concentrations but there was more than 95% hatched in control in 10-11 days after spawning. Egg development was completely inhibited at 100 μg L(-1), while abnormal embryonic development observed at 32 and 56 μg L(-1) of Cu. The Cu concentration in tissues increased in Cu treated snails and bioaccumulation factor ranged from 2.3 to 18.7. Snail growth at 5.6 and 10 μg L(-1) was reduced by 6.2% and 16.9%, respectively. The study revealed that snail embryos and adults could be used as in vivo test models for ecotoxicological studies. Findings of present study are helpful for advancing water quality guidelines for protecting aquatic biota.  相似文献   
105.
A newly identified member of the tumor necrosis factor receptor (TNFR) superfamily shows activities associated with osteoclastogenesis inhibition and fibroblast proliferation. This new member, called TR1, was identified from a search of an expressed sequence tag database, and encodes 401 amino acids with a 21-residue signal sequence. Unlike other members of TNFR, TR1 does not contain a transmembrane domain and is secreted as a 62 kDa glycoprotein. TR1 gene maps to chromosome 8q23-24.1 and its mRNA is abundantly expressed on primary osteoblasts, osteogenic sarcoma cell lines, and primary fibroblasts. The receptors for TR1 were detected on a monocytic cell line (THP-1) and in human fibroblasts. Scatchard analyses indicated two classes of high and medium-high affinity receptors with a kD of approximately 45 and 320 pM, respectively. Recombinant TR1 induced proliferation of human foreskin fibroblasts and potentiated TNF-induced proliferation in these cells. In a coculture system of osteoblasts and bone marrow cells, recombinant TR1 completely inhibited the differentiation of osteoclast-like multinucleated cell formation in the presence of several bone-resorbing factors. TR1 also strongly inhibited bone-resorbing function on dentine slices by mature osteoclasts and decreased 45Ca release in fetal long-bone organ cultures. Anti-TR1 monoclonal antibody promoted the formation of osteoclasts in mouse marrow culture assays. These results indicate that TR1 has broad biological activities in fibroblast growth and in osteoclast differentiation and its functions.  相似文献   
106.
OBJECTIVE: The purpose of this study was to assess the efficacy of fluvoxamine in the treatment of binge-eating disorder. Binge-eating disorder is a newly described eating disorder characterized by recurrent episodes of binge eating but without purging behaviors. Uncontrolled reports have suggested that serotonin selective reuptake inhibitors (SSRIs) may be effective in treating this disorder. METHOD: Eighty-five outpatients with a DSM-IV diagnosis of binge-eating disorder were randomly assigned to receive either fluvoxamine (N=42) or placebo (N=43) in a 9-week, parallel-group, double-blind, flexible dose (50-300 mg) study at three centers. The primary outcome measures were frequency of binge eating, expressed as log ([binges/week]+1), and Clinical Global Impression (CGI) scale ratings. Secondary measures included the level of response (based on the percentage change in frequency of binges), body mass index, and Hamilton Rating Scale for Depression score. Except for the level of response, the outcome measures were analyzed by random regression methods; the treatment-by-time interaction was the measure of treatment effect. RESULTS: Compared with placebo, fluvoxamine was associated with a significantly greater rate of reduction in the frequency of binges, rate of reduction in CGI severity scores, rate of increase in CGI improvement scores, level of response for patients who completed the 9-week study, and rate of reduction in body mass index. There was no significant difference between placebo and fluvoxamine groups in the rate of decrease in Hamilton depression scale scores. A significantly greater proportion of patients receiving fluvoxamine than those receiving placebo discontinued treatment because of an adverse medical event. CONCLUSIONS: In this placebo-controlled trial, fluvoxamine was found to be effective according to most outcome measures in the acute treatment of binge-eating disorder.  相似文献   
107.
The [Tyr5,12,Lys7]-polyphemusin II peptide (T22) inhibits HIV-1 replication in lymphocytes. The mechanism of T22 inhibition of HIV-1 replication may involve T22 competition with HIV-1 for attachment sites on the plasma membrane of targeted cells. Here we find that the T22 peptide binds to the CD4 molecule in affinity columns. We also find that antiserum to CD4 inhibits cell attachment to T22. Further CD4+ transfected cells attach to T22 while their parental cells which do not express CD4 do not attach to T22. These data demonstrate that T22 binds to the CD4 molecule and supports the hypothesis that T22 inhibits HIV-1 replication by binding to the cell surface CD4 molecule and inhibiting uptake of the virus.  相似文献   
108.
The putative E1 of hepatitis C virus (HCV) was expressed in Escherichia coli using a glutathione-S-transferase (GST) fusion protein system. The full length E1 protein is difficult to express. A series of E1 DNA fragments was generated and used for expression vector construction. Fusion proteins containing the E1 C-terminal region could not be expressed. When this region was truncated, the fusion proteins were synthesized to high levels. The possibility of this C-terminal region hampering the production of fusion protein was further explored. A construct with this segment directly fused to the C-terminus of GST indeed generated no detectable recombinant protein. According to the predicted structure of E1, this region may have membrane-associating properties. The expression results suggest a general approach to facilitate the production of viral membrane proteins in prokaryotes. Furthermore, these recombinant E1 proteins generated as antigens were used for Western blotting with sera from HCV-infected individuals. It was found that E1 is antigenic during HCV natural infection.  相似文献   
109.
Pain assessment and physical examination are the first crucial steps in diagnosis of neuropathic pain disorders because these are still solely diagnosed on clinical grounds. The physical examination should be conducted in such a way that all of the positive sensory phenomena, such as allodynia, hyperalgesia, hyperpathia, summation, and after-sensation are elicited. Other physical examination findings should corroborate the diagnostic impression of neuropathic pain. Specific pain diagnosis should then lead to more specific therapy.  相似文献   
110.
BACKGROUND: Closure of a large ventricular septal defect (VSD) in children with elevated pulmonary vascular resistance is associated with significant morbidity and mortality. Pulmonary hypertensive episodes continue to be a major cause of postoperative morbidity and mortality. We designed a fenestrated flap valve double VSD patch in an effort to decrease the morbidity and mortality associated with the closure of a large VSD with elevated pulmonary vascular resistance. METHODS: Eighteen children (mean age, 5.7 years) with a large VSD and elevated pulmonary vascular resistance (mean, 11.4 Wood units) underwent double patch VSD closure using moderately hypothermic cardiopulmonary bypass and cardioplegic arrest. The routine VSD patch was fenestrated (4 to 6 mm) and on the left ventricular side of the patch, a second, smaller patch was attached to the fenestration along its superior margin before closure of the VSD. RESULTS: All children survived operation and were weaned from inotropic and ventilator support within 48 hours postoperatively. Postoperative pulmonary artery pressures were significantly lower than preoperative values. One child died 9 months postoperatively. CONCLUSIONS: Closure of a large VSD in children with elevated pulmonary vascular resistance can be performed with low morbidity and mortality when a flap valve double VSD patch is used.  相似文献   
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