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1.
ObjectivesTo fill an empirical gap in the literature by examining changes in quality of care measures occurring when multispecialty clinic systems were acquired by hospital-owned, vertically integrated health care delivery systems in the Twin Cities area.ConclusionsMoving a clinic system into a vertically integrated delivery system resulted in limited increases in quality of care indicators. Caution is warranted when the acquisition causes disruption in referral patterns.  相似文献   
2.
Kiaei  Lily  Kiaei  Mahmoud 《Metabolic brain disease》2022,37(6):1697-1702
Metabolic Brain Disease - Amyotrophic lateral sclerosis (ALS), a fatal neurodegenerative disease, leads to the loss of motor neurons. There are currently no effective therapies to treat this...  相似文献   
3.
BACKGROUND: Abnormalities in calcium and vitamin D metabolism have been reported after bariatric surgery. The purpose of this study was to evaluate vitamin D nutritional status among morbidly obese patients before gastric bypass surgery. METHODS: We prospectively studied 279 morbidly obese patients seeking gastric bypass surgery for vitamin D nutritional status as assessed by serum 25-hydroxyvitamin D level. In addition, serum samples were analyzed for calcium, alkaline phosphatase (AP), intact parathyroid hormone (PTH), and 1,25-dihydroxyvitamin D. RESULTS: Mean patient age was 43 +/- 9 years; 87% of the study patients were women, and 72% were white. Serum calcium and AP levels were normal in 88% and 89% of the patients, respectively. Vitamin D depletion, defined as serum 25-hydroxyvitamin D level 相似文献   
4.
This study assessed the amount of vascular endothelial growth factor (VEGF) expression and related the findings to new bone formation in the posterior glenoid fossa during stepwise mandibular advancement. A total of 250 female Sprague-Dawley rats, 35 days old, were randomly divided into 10 groups, each including 5 control and 20 experimental rats. Within each group, 10 experimental rats were fitted with functional appliances with a 1-step advancement of 3.5 mm. Another 10 were fitted with stepwise appliances with an initial advancement of 2 mm and a subsequent increase to 3.5 mm on day 30. The rats in the experimental groups were killed on days 3, 7, 14, 21, 30, 33, 37, 44, 51, and 60, respectively. The matched controls were killed on the same time points. Sections (7 microm) were cut through the glenoid fossa sagittally and stained with anti-VEGF antibody. VEGF expression in the posterior glenoid fossa was evaluated with a computer-assisted image-analyzing system. Both VEGF expression and new bone formation were greater in the experimental rats than in the controls. During stepwise advancement, initial VEGF expression was less than that of 1-step advancement, but the second advancement elicited another peak on day 44. New bone formation was also less than that of 1-step advancement during early stages of stepwise advancement but then began to increase from day 37 onward. The maximum increase was observed on day 60. Stepwise advancement of the mandible delivers mechanical stimuli that produce a series of tissue responses that lead to increased vascularization and bone formation.  相似文献   
5.
The effects of sulphasalazine on the production of second messenger compounds in human granulocytes have been characterised by various stimuli. The increases in cytosolic calcium, inositol trisphosphate, diacylglycerol, and phosphatidic acid (all important mediators of intracellular signal transduction) triggered by stimulation were inhibited by sulphasalazine. The metabolites 5-amino-salicylic acid and sulphapyridine were less potent inhibitors than the mother compound. It is concluded that sulphasalazine inhibits the synthesis of phosphoinositide derived second messenger compounds at the level of phospholipase C or its regulatory guanosine 5'-triphosphate (GTP) binding protein. Inhibition of phosphatidic acid synthesis was either due to the same mechanism, or to interaction with a phospholipase D regulating GTP binding protein.  相似文献   
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The disposition of [14C]finasteride, a competitive inhibitor of steroid 5 alpha-reductase, was investigated after oral administration of 38.1 mg (18.4 microCi) of drug in six healthy volunteers. Plasma, urine, and feces were collected for 7 days and assayed for total radioactivity. Concentrations of finasteride and its neutral metabolite, omega-hydroxyfinasteride (monohydroxylated on the t-butyl side chain), in plasma and urine were determined by HPLC assay. Mean excretion of radioactivity equivalents in urine and feces equaled 39.1 +/- 4.7% and 56.8 +/- 5.0% of the dose, respectively. The mean peak plasma concentrations reached for total radioactivity (ng equivalents), finasteride, and omega-hydroxyfinasteride were 596.5 +/- 88.3, 313.8 +/- 99.4, and 73.7 +/- 11.8 ng/ml, respectively, at approximately 2 hr; the mean terminal half-life for drug and metabolite was 5.9 +/- 1.3 and 8.4 +/- 1.7 hr, respectively. Of the 24-hr plasma radioactivity, 40.9% was finasteride, 11.8% was the neutral metabolite, and 26.7% was characterized as an acidic fraction of radioactivity. Binding of [14C]finasteride to plasma protein was extensive (91.3 to 89.8%), with a trend suggesting concentration dependency (range 0.02 to 2 micrograms/ml). Little of the dose was excreted in urine as parent (0.04%) or omega-hydroxyfinasteride (0.4%). Urinary excretion of radioactivity was largely in the form of acidic metabolite(s)--18.4 +/- 1.7% of the dose was eliminated as the omega-monocarboxylic acid metabolite. Finasteride was scarcely excreted unchanged in feces. In humans, finasteride is extensively metabolized through oxidative pathways.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
8.
OBJECTIVE: To evaluate the efficacy of methylphenidate in treating adults with attention-deficit hyperactivity disorder (ADHD), using subjective (self-report) and objective (computerized test) measures. METHOD: This double-blind crossover trial of placebo vs methylphenidate included subjects with childhood and current ADHD symptoms, IQs above 80, no other psychiatric condition explaining their difficulties or requiring other treatment, and no substance abuse in the previous 6 months. We administered 10 mg 3 times daily of medication (that is, placebo or methylphenidate) for 2 weeks. On the final day, subjects completed self-report measures and were tested on computerized tests. We then increased dosage to 15 mg 3 times daily for 2 weeks and administered a complete reassessment on the final day. Following a 1-week washout, we repeated this process on the second medication (that is, placebo or methylphenidate). RESULTS: Thirty adults with ADHD participated. Self-report measures and computerized tests showed significant improvements in ADHD symptoms on methylphenidate, compared with placebo. Other psychiatric symptoms (notably, anxiety and depression) were alleviated with methylphenidate. There was no significant difference between the 2 dosages of methylphenidate. CONCLUSION: Methylphenidate is effective in improving ADHD symptoms in adults with ADHD, is well tolerated, and has minimal side effects.  相似文献   
9.
This study retrospectively compares patients who underwent outpatient transvaginal follicle aspiration with either a propofol- or methohexital-based intravenous sedation technique. Data collected from patient charts (n = 212) over a 46-month period were analyzed to determine the effects of each sedation technique on procedure and recovery times, number of retrieved ova, as well as rates of nausea, fertilization, cleavage, pregnancy, and delivery. All patients were included in the study, regardless of age or diagnosis. procedure time was lower in the propofol group (51 t 18 min) than in the methohexital group (61 I 20 min) (p > 0.01). Patients in the methohexital group (139 2 51 min) spent more time in the recovery room than did those in the propofol group (71 ? 34 min) (p > 0.01). The nausea rates were significantly lower in the propofol group compared with the methohexital group (1.9% vs. 14.4%, respectively) (p > 0.02). Fertilization rate in the propofol group was 77.7% and was 62.9% in the methohexital group (p > 0.01). The numbers of retrieved ova and the cleavage rates were similar in both groups. The rate of pregnancy in patients sedated with propofol (46.1%) was higher than the methohexital group (26.9%) (p > 0.02). Delivery rate was 38.5% in the propofol group and 20.6% in the methohexital group (p > 0.02). In summary, propofol intravenous sedation for transvaginal follicle aspiration was associ- ated with an improved outcome. Pregnancy and delivery rates were higher while nausea, an unpleasant side effect, was sharply reduced.  相似文献   
10.
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