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101.
The present study examined further the pharmacological specificity of the methylxanthine CNS stimulant caffeine as a discriminative stimulus in humans. Nine normal healthy volunteers (ages 19-39) were trained to discriminate between caffeine (320mg/70kg, p.o.) and placebo, using monetary reinforcement of correct letter code identification. After four training sessions, subjects were tested with the training conditions until they were >80% correct on four consecutive sessions. Then dose-effect curves were determined for caffeine (56-320mg/70kg), theophylline (56-320mg/70kg), methylphenidate (10-56mg/70kg), and buspirone (1-32mg/70kg). Seven of nine subjects met the discrimination criterion within four to nine sessions. During dose-effect curve determinations, caffeine and methylphenidate each produced dose-related increases in caffeine-appropriate responding. Theophylline produced caffeine-appropriate responding that was not dose related in a consistent manner across subjects, occasioning an average of 50% caffeine-appropriate responding at most doses tested. Buspirone produced predominantly placebo-appropriate responding. Caffeine-appropriate responding tended to be directly related to ARCI LSD scores, self-reported "bad" effects, "high", and stimulant-bad effects and inversely related to ARCI PCAG scores and sedative ratings. These results agree with non-human data and suggest that the caffeine discriminative stimulus has pharmacological specificity, in that caffeine-appropriate responding generalizes to other stimulants such as theophylline or methylphenidate, but not to non-stimulant compounds such as buspirone.  相似文献   
102.
Telegenetics has shifted some genetic testing performance to the patient's own home, with the patient collecting his/her own sample. Little is known regarding the rate of test completion of such home-based genetic testing. This study compared the completion rate of home-based genetic tests before and after a reminder system was implemented. In the pre-reminder group, we reviewed medical records for patients who were seen via telegenetics and agreed to complete genetic testing using an at-home test kit. In the reminder group, a prospective analysis of the genetic test completion rate was performed taking a clinical quality improvement approach where three reminders were provided for patients who had not submitted their at-home genetic testing. Our study included 94 patients' records: 46 pre-reminders and 48 reminders. The lab received 24 patient samples (52.2%) in the pre-reminder group. In the reminder group, 30 patients returned their kits (62.5%). Despite a higher percentage of patients completing their test in the reminder group, there was no statistically significant difference between the pre-reminder and reminder groups. The rate of test completion in our pilot test was statistically similar between the two groups, but the reminder group was trending toward a higher percent of completion which may be clinically meaningful.  相似文献   
103.
Sacramento, California's capital, represents the nation's most competitive managed care marketplace. The Sutter Health organization represents a significant force in this marketplace and surrounding regions of Northern California. Sutter has created an integrated regional health care network capable of delivering a full continuum of care through appropriate community-based facilities, a variety of physician relationships, and both owned and aligned managed care structures. The overall Sutter Health strategy that incorporates facilities, physician partnerships, and patient care financing is described. The article identifies six key lessons learned during this period of growth.  相似文献   
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Summary The relationships of INT2 and ERBB2 amplification and of ERBB2 overexpression in primary breast tumors to prognostic factors, recurrence, and survival have generated considerable controversy. The rationale for this study is that long-term, recurrence-free survival is a more direct criterion for testing the validity of a tumor marker than correlation either with prognostic factors or with short-term recurrence and survival. We examined the association of recurrence with INT2 and ERBB2 amplification and ERBB2 expression by comparing primary breast tumors from patients surviving without recurrence for 8.5 years after diagnosis. the LTS group, to tumors from patients recurring within two years, the RR group. The RR (N = 63) and LTS (N = 61) samples were coded and examined for amplification by Southern blotting and for expression by immunohistochemistry. Comparison between the RR and LTS groups demonstrated that INT2 amplification was associated with a significantly (P = 0.018) higher (5.6-fold) risk of recurrence, an association that remained significant after controlling for lymph node (LN), tumor size (TS), and histograde (HG) status. ERBB2 amplification and expression were not associated with a higher recurrence risk. Survival analyses within the RR group, however, demonstrated significantly shorter survival time among cases with than without ERBB2 amplification (P = 0.018, median survival 16 vs 25 months), or ERBB2 expression (P = 0.019, median survival 15 vs 25 months), but not INT2 amplification. Univariate Cox proportional hazards regression models also demonstrated significantly shorter survival among cases with ERBB2 amplification (P = 0.016) or expression (P = 0.049), that remained significant in multivariate analyses (P = 0.022) for ERBB2 amplification. These results indicate a significant positive association between INT2 amplification and risk for tumor recurrence in the RR as compared to the LTS group. The relationship of ERBB2 amplification or overexpression to patient outcome is more complex. ERBB2 amplification and expression have a significant relationship with shorter survival among patients recurrent within two years, but their occurrence in tumors from women surviving without recurrence for 8.5 years suggests that ERBB2 status is not predictive of shorter survival for all breast cancers.  相似文献   
107.
Because of the limited number of case reports on the use of electroconvulsive therapy (ECT) in adolescent psychiatric patients, we retrospectively reviewed the medical records of 20 young patients who underwent ECT. They constituted all the patients 相似文献   
108.
Nonsteroidal antiandrogens (AA) cannot be topically used for androgenetic alopecia (AGA) because of systemic resorption. A new class of androgen receptor (AR) suppressors designed for safe topical treatment of AGA was synthesized from (3‐amino‐2‐hydroxy‐2‐methyl‐N‐(4‐nitro‐3‐trifluoromethyl)phenyl) propanamide (BP‐34), to contain perfluoroalkyl moieties. The trifluoromethyl derivative (fluridil) at 10 μM decreased expression of the AR in LNCaP human cells by 95%, its serum half‐life was 6 h; it decomposes hydrolytically to BP‐34 and trifluoroacetic acid. Acute intraperitoneal maximum tolerated dose (MTD) of fluridil in mice is 270–300 mg/kg/d and the subacute MTD is 450 mg/kg/d. The oral LD50 in mice was 2,872 mg/kg in males, 2,232 mg/kg in females, and >2,500 mg/kg in rats. Fluridil solution in isopropanol was not cutaneously absorbed in rabbits, did not sensitize or show any phototoxic or photoallergic effects on guinea pig skin, and demonstrated no skin irritation potential in rabbits and humans. Fluridil solid induced only slight and reversible eye irritancy in rabbits and displayed no cytotoxicity to rabbit corneal fibroblasts in vitro. Fluridil demonstrated no significant mutagenicity potential by Ames method. In a double‐blind study, 43 males with AGA, Norwood grade II to Va, used topical 2% fluridil in isopropanol or the vehicle daily for 12 months. Anagens (growing hairs) increased in the fluridil group from 76% to 89%. All hematological and biochemistry values remained within normal range, including testosterone, which varied but seasonally. No fluridil or its decomposition product (BP‐34) was detected in serum. No adverse side effects were reported. Drug Dev. Res. 59:292–306, 2003. © 2003 Wiley‐Liss, Inc.  相似文献   
109.
PURPOSE: We have proposed to characterize the mechanism through which bioactive surgical sutures generate a T(H)1 immune response and to define the immune-stimulating half-life of the sutures. EXPERIMENTAL DESIGN: Bioactive sutures of interferon gamma (IFNgamma), interleukin 2 (IL-2), anti-CD3/CD28, anti-CD3/CD28 + IL-2, or anti-CD3/CD28 + IFNgamma sutures were used to stimulate lymphocytes from normal donors and from head and neck cancer patients in vitro over a 24-day period. Cell supernatants were analyzed by ELISA, and T cells were phenotyped to characterize the immune response generated. Intracellular cytokine staining was performed to measure the expansion of flu-specific T cells. Electromobility shift assay and supershift assay were used to measure the intranuclear DNA binding activity of nuclear factor kappaB and its p65 subunit in T cells activated by sutures in the presence and absence of a proteasome inhibitor, MG-132. RESULTS: Anti-CD3/CD28, anti-CD3/CD28 + IL-2, or anti-CD3/CD28 + IFNgamma generated a prolonged T(H)1 immune response for 18 days in vitro. Anti-CD3/CD28 expanded flu-specific T cells. Activated T cells demonstrated enhanced CD40 ligand (CD40L) expression within 72 hours of stimulation, which stimulated other cells to secrete IL-12. Stimulated T cells demonstrated increased intranuclear expression of nuclear factor-kappaB, which was blocked by MG-132, and also reduced CD40L and IL-12 expression. CONCLUSIONS: This is the first report to demonstrate that bioactive surgical sutures can generate a prolonged T(H)1 immune response and expand flu-specific T cells. Bioactive sutures, which are primarily a T-cell stimulant, also stimulated other cells to secrete IL-12 and prolonged the immune response. Sutures may provide a novel in situ stimulating strategy for enhancing the immune system of cancer patients.  相似文献   
110.
Phase II trial of gefitinib in recurrent glioblastoma.   总被引:13,自引:0,他引:13  
PURPOSE: To evaluate the efficacy and tolerability of gefitinib (ZD1839, Iressa; AstraZeneca, Wilmington, DE), a novel epidermal growth factor receptor tyrosine kinase inhibitor, in patients with recurrent glioblastoma. PATIENTS AND METHODS: This was an open-label, single-center phase II trial. Fifty-seven patients with first recurrence of a glioblastoma who were previously treated with surgical resection, radiation, and usually chemotherapy underwent an open biopsy or resection at evaluation for confirmation of tumor recurrence. Each patient initially received 500 mg of gefitinib orally once daily; dose escalation to 750 mg then 1,000 mg, if a patient received enzyme-inducing antiepileptic drugs or dexamethasone, was allowed within each patient. RESULTS: Although no objective tumor responses were seen among the 53 assessable patients, only 21% of patients (11 of 53 patients) had measurable disease at treatment initiation. Seventeen percent of patients (nine of 53 patients) underwent at least six 4-week cycles, and the 6-month event-free survival (EFS) was 13% (seven of 53 patients). The median EFS time was 8.1 weeks, and the median overall survival (OS) time from treatment initiation was 39.4 weeks. Adverse events were generally mild (grade 1 or 2) and consisted mainly of skin reactions and diarrhea. Drug-related toxicities were more frequent at higher doses. Withdrawal caused by drug-related adverse events occurred in 6% of patients (three of 53 patients). Although the presence of diarrhea positively predicted favorable OS from treatment initiation, epidermal growth factor receptor expression did not correlate with either EFS or OS. CONCLUSION: Gefitinib is well tolerated and has activity in patients with recurrent glioblastoma. Further study of this agent at higher doses is warranted.  相似文献   
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