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71.
The St. John's Wort (Hypericum perforatum) extract (Hp) represents one of the most useful natural therapeutic agents in the treatment of moderate and mild depression. The antidepressant effects of Hp are different, by a molecular mechanism point of view, when compared to those of other antidepressant drugs and, we think, a further pharmacological characterization is needed. It is suggested that the neurochemical effects of Hp could be bind either to its activity on the uptake of some mediators in the central nervous system or to the inhibition of some enzymatic activity at the receptor level. The present study carried out with the loose patch clamp (LPC) in the mouse neuromuscular junction, indicates a potentiation of the acetylcholine (ACh) action at the mouse neuromuscular junction. The spontaneous release of ACh was unaffected by Hp indicating that neither presynaptic nor postsynaptic function are modified by Hp. Indeed, both the frequency and the amplitude of the miniature end-plate currents (mepcs) were unmodified by Hp. Furthermore, the mepcs decay time (tau), i.e. the apparent cholinergic channel life time, was significantly increased after Hp treatment. The other parameter affected was the amplitude of the evoked end-plate currents (epcs) which was constantly and in a dose dependent manner increased by Hp. These findings suggest a possible action of Hp on the acetylcholinesterase (AChE) in terms of a reduction of the degradation rate of ACh.  相似文献   
72.
The therapeutic alliance is a well-studied construct factor that is important to outcome in many forms of individual therapy. Therapeutic alliance has been rarely studied in group therapy and results in addiction treatment have been mixed. In this paper, we studied the presence of a therapeutic alliance in Network Therapy: an approach that uses peer and family support in addiction treatment. Twenty-one participants undergoing Network Therapy for cocaine addiction were observed on videotape, and were rated on therapeutic alliance using the Working Alliance Inventory and the Penn Helping Alliance Rating Scale. Results showed a significant positive correlation between therapeutic alliance and outcome as measured by the percentage of cocaine-free urine toxicology screens and by eight consecutive cocaine-free urines.  相似文献   
73.
This study analysed the effect of low doses ofverapamil added to chronic treatment withangiotensin-converting enzyme (ACE) inhibitors onblood pressure and serum creatinine levels in eightelderly hypertensive patients who had a steadyincrease of serum creatinine while on ACE inhibitors.The study was performed in eight elderly hypertensivesubjects, five men and three women (mean age 70 ±2 years; systolic blood pressure 173 ± 4 mmHg; diastolic blood pressure 99 ± 1 mm Hg) andserum creatinine of 1.60 ± 0.27 mg/dl beforetreatment. During an average of 25 weeks, ACEinhibitors significantly reduced both systolic anddiastolic blood pressures, but serum creatinine levelswere increased over basal levels (0,68 ± 0,20 mg/dl, p < 0.05). During an average of 10 weeks,the addition of verapamil did not decrease bloodpressure further, but serum creatinine levels werereduced to baseline. Our study suggests that theaddition of verapamil to ACE inhibitors can reverseACE-induced increase in creatinine levels in elderlyhypertensive patients in whom this side effect isobserved. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
74.
PURPOSE: To evaluate safety and preliminary efficacy of the humanized anti-epidermal growth factor receptor monoclonal antibody h-R3 in combination with radiotherapy (RT) in unresectable head and neck cancer patients. Secondary end points were the measurement of h-R3 serum levels and the assessment of the potential mechanisms of antitumor effect on patient biopsies. Anti-idiotypic response to h-R3 was assessed. To predict pharmacologic effect, a mathematical model for antibodies recognizing antigens expressed in tumors and normal tissues was built. PATIENTS AND METHODS: Twenty-four patients with advanced carcinomas of the head and neck received six once-weekly infusions of h-R3 at four dose levels in combination with RT. Pretreatment tumor biopsies were obtained to evaluate epidermal growth factor receptor expression as an enrollment criterion. Second biopsies were taken to evaluate the proliferative activity and angiogenesis in comparison with the pretreatment samples. Patient serum samples were collected to measure h-R3 levels and anti-idiotypic response. RESULTS: The combination of h-R3 and RT was well tolerated. Antibody-related adverse events consisted in infusion reactions. No skin or allergic toxicity appeared. Overall survival significantly increased after the use of the higher antibody doses. Immunohistochemistry studies of tumor specimens before and after treatment revealed that antitumor response correlated with antiproliferative and antiangiogenic effect. One patient developed antibodies to h-R3. The mathematical model predicted that the maximum difference between the area under the curve in tumors and normal tissues is reached when the antibody has intermediate affinity. CONCLUSION: h-R3 is a well-tolerated drug that may enhance radiocurability of unresectable head and neck neoplasms.  相似文献   
75.
PURPOSE: The aim of the present study was to potentiate the antitumor effectiveness of photodynamic therapy (PDT). A cDNA microarray analysis was used to evaluate the gene expression pattern after Photofrin-mediated PDT to find more effective combination treatment with PDT and inhibitor(s) of the identified gene product(s) overexpressed in tumor cells. EXPERIMENTAL DESIGN: Atlas Mouse Stress Array was used to compare the expression profile of control and PDT-treated C-26 cells. The microarray results have been confirmed using Western blotting. Cytostatic/cytotoxic in vitro assay as well as in vivo tumor models were used to investigate the antitumor effectiveness of PDT in combination with cyclooxygenase (COX) 2 inhibitors. RESULTS: PDT induced the expression of 5 of 140 stress-related genes. One of these genes encodes for COX-2, an enzyme important in the tumor progression. Inhibition of COX-2 in vitro with NS-398, rofecoxib, or nimesulide, or before PDT with nimesulide did not influence the therapeutic efficacy of the treatment. Administration of a selective COX-2 inhibitor after PDT produced potentiated antitumor effects leading to complete responses in the majority of treated animals. CONCLUSIONS: COX-2 inhibitors do not sensitize tumor cells to PDT-mediated killing. However, these drugs can be used to potentiate the antitumor effectiveness of this treatment regimen when administered after tumor illumination.  相似文献   
76.
Knowledge concerning patterns of health care utilization among Latino-adolescent immigrants is needed to develop culturally-appropriate programs. The objectives of this study were to estimate the annual prevalence of having had a routine physical exam and episodes of adolescents’ not seeking health care when they thought they should (forgone health care) among Latino adolescents by immigrant-generational status. Cross-sectional analysis of data from Latino adolescents in Wave I of the National Longitudinal Adolescent Health Study. First-generation immigrants who had lived in the U.S. ≤ 5 years were less likely to receive routine care than third-generation immigrants (39.0% vs. 54.9%). This disparity decreased after adjustment for insurance status, parental education and poverty among Mexican origin adolescents. On average, 16.0% of first-generation immigrants who had lived in the U.S. ≤ 5 years and 22.5% of third-generation immigrants reported forgoing health care. After adjustment for age, insurance status, parental education and routine care, recent arrivals were less likely than third-generation immigrants to forgo health care. Recent arrivals were less likely to receive a routine physical exam and to forgo care than third-generation immigrants. Future studies should explore the effect of acculturation on knowledge, beliefs and perceptions about health, illness and care-seeking behaviors.  相似文献   
77.
78.
PURPOSE: Ifosfamide, carboplatin, and etoposide (ICE) are associated with grade III/IV dose-limiting thrombocytopenia. The Children's Oncology Group conducted a phase I dose escalation, pharmacokinetic, and biological study of recombinant human thrombopoietin (rhTPO) after ICE in children with recurrent/refractory solid tumors (CCG-09717) to assess the toxicity and maximum tolerated dose of rhTPO administered at 1.2, 2.4, or 3.6 microg/kg per dose. EXPERIMENTAL DESIGN: Children received ifosfamide 1,800 mg/m2 on days 0 to 4, carboplatin 400 mg/m2 on days 0 to 1, and etoposide 100 mg/m2 on days 0 to 4. rhTPO was administered i.v. on days +4, +6, +8, +10, and +12 at 1.2, 2.4, or 3.6 microg/kg per dose.RESULTS: rhTPO was well tolerated and maximum tolerated dose was not reached. Median time to platelet recovery > or =100,000/microL of rhTPO at 1.2, 2.4, and 3.6 microg/kg/d was 24 days (22-24 d), 25 days (23-29 d), and 22 days (16-37 d), respectively. Patients required a median of 2 days of platelet transfusions (0-7 days). Mean (+/- SD) rhTPO maximum serum concentrations were 63.3 +/- 9.7 and 89.3 +/- 15.7 ng/mL and terminal half-lives were 47 +/- 13 and 64 +/- 42 hours after 2.4 and 3.6 microg/kg/d, respectively. There was a significant increase in colony-forming unit megakaryocyte upon WBC count recovery. CONCLUSIONS: rhTPO was well tolerated. Time to hematologic recovery and median number of platelet transfusions seem to be improved compared with historical controls receiving ICE + granulocyte colony-stimulating factor (CCG-0894).  相似文献   
79.
80.
Background: Excessive mileage can be detrimental to bone mineral density among long-distance runners. The negative effects of mileage could be alleviated by appropriate nutrition. The purpose of this study was to analyse the dietary-lifestyle patterns in relation to bone mineral density and bone turnover markers among amateur marathoners. Methods: A total of 53 amateur male distance runners were divided into two clusters by k-means cluster analysis. Bone mineral density was measured by dual X-ray absorptiometry (DXA). Blood was drawn to analyse bone resorption marker C-terminal telopeptide (cTX) and bone formation marker amino-terminal propeptide of type I collagen (PINP). Food frequency intake and lifestyle information were measured by multicomponent questionnaire KomPAN®. Yearly average mileage per month was taken from each participant. Results: There were two distinguished clusters: Less-healthy-more-active-low-Z-score (LessHA) (n = 33) and More-healthy-less-active-high-Z-score (MoreHLA) (n = 20). LessHA had a lower frequency intake of pro-healthy food groups, a lower number of meals during a typical day, and a higher mileage training than the group of athletes who followed the MoreHLA. Athletes following the LessHA pattern also had a lower Z-score in the lumbar spine and femoral bone and a lower PINP. Conclusion: The current study suggests that pro-healthy dietary patterns and lower mileage may favour higher bone mineral density in male amateur marathoners.  相似文献   
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