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951.
We evaluate the change in length-of-stay and charges for vaginal and cesarean deliveries before and after the implementation of a law establishing a minimum maternity stay in Maryland. Using discharge abstract data collected by the Maryland Health Services Cost Review Commission, we find that after the law was enacted, Maryland's average length-of-stay and average charges for both types of deliveries increased, but the increase in charges was less than the cost of an average hospital day. Multivariate analysis shows that the implementation of the law reduced the sources of variation among mothers' length-of-stay and hospital charges. Overall, we estimate that the law cost payers an additional $5.5 million for maternity stays.  相似文献   
952.
An 89-year-old woman with recurrent conjunctival mucoepidermoid carcinoma developed intraocular inflammation and an elevated fundus lesion that simulated choroidal detachment in her affected right eye. Intraocular invasion of squamous cell carcinoma was suspected and the eye was enucleated. Pathologic examination of the enucleated eye showed intraocular invasion by conjunctival mucoepidermoid carcinoma that formed a suprauveal cyst lined with malignant epithelial cells. The patient developed an orbital recurrence 1 year later and underwent orbital exenteration. She died 2 years later from an unrelated cause. Conjunctival mucoepidermoid carcinoma can exhibit intraocular invasion and produce an intraocular neoplastic cyst.  相似文献   
953.
We report the clinical case of a man who survived a massive attack of Africanized bees (>2000 bee stings). The man experienced anaphylactic shock and multisystem organ failure (neurologic, hepatic, renal, and hematologic failure). He was treated with administration of dopamine hydrochloride, antihistaminic agents, corticosteroids, fluid and electrolyte replenishment, peritoneal dialysis, and plasmapheresis. No sequelae have been observed during follow-up.  相似文献   
954.
Microiontophoretic drug application and extracellular recording techniques were used to evaluate the effects of the selective metabotropic glutamate receptor (mGluR) agonist (1S,3R)-1-aminocyclopentane-1,3-dicarboxylate(1S,3R-ACPD) on dopamine (DA) neurons in the substantia nigra zona compacta (SNZC) of chloral hydrate-anesthetized rats. 1S,3R-ACPD had a biphasic effect on the firing rate of DA cells, initially decreasing, then increasing the firing rate. 1S,3R-ACPD also increased the burst-firing activity of DA neurons. Application of the ionotropic receptor (iGluR) agonists (R,S)-alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA) or N-methyl-D-aspartate (NMDA) increased the firing rates of neurons which had responded to 1S,3R-ACPD, indicating that mGluRs and iGluRs reside on the same neurons. The initial inhibitory period was not antagonized by systemic haloperidol or iontophoretic bicuculline, indicating a lack of DA or gamma-amino-n-butyric acid (GABA) involvement in this effect. Combined application of the AMPA antagonist, 2,3-dihydroxy-6-nitro-7-sulfamoylbenzo(f)quinoxaline (NBQX), and the NMDA antagonist, (I)-3-(2-carboxypiperazin-4-yl)propyl-1-phosphoric acid (CPP), at currents which antagonized AMPA and NMDA, did not antagonize either the inhibitory or excitatory effects of 1S,3R-ACPD. Application of the metabotropic antagonist (S)-4-carboxy-phenylglycine antagonized both the inhibitory and excitatory effects of 1S,3R-ACPD. These results indicate that mGluRs may play a role in the modulation of dopaminergic activity in the SNZC.  相似文献   
955.
Investment in medical technology innovation has enabled significant advances in patient care. An understanding of the dimensions and measures of innovation is critical in fully assessing the implications of many policy initiatives under debate. This Data Watch presents several indicators of inputs and outputs associated with medical device innovation, including public- and private-sector research and development (R&D) investment, patent activity, product regulatory clearance patterns, and market acceptance trends. Changes in these selected indicators point to a potential shift occurring in both the nature of and the investors in the innovation process.  相似文献   
956.
957.
Human epileptics have been reported to have low blood manganese (Mn) concentrations in comparison to nonepileptics, an observation that is important because Mn deficiency can increase seizure susceptibility in experimental animals. Factors that have been suggested to contribute to the low blood Mn levels in epileptics include anticonvulsant use, seizure-induced tissue redistribution of Mn, and genetics; in the present study, the first of these possibilities was tested. Wistar rats were fed semipurified diets containing diphenylhydantoin ([DPH] 3 g/kg diet), phenobarbital ([PB] 2 g/kg diet), or primidone ([PRIM] 3 g/kg diet) for 7 weeks, at which time they were killed and tissues collected and analyzed for Mn, zinc (Zn), copper (Cu), and iron (Fe) concentrations. In comparison to pair-fed rats, DPH- and PRIM-fed rats had significantly elevated liver Mn concentrations, while Mn concentrations in blood, brain, heart, and kidney were unaffected by anticonvulsant exposure. Changes in the concentrations of Zn, Cu, and Fe in specific tissues were also found. Overall, these findings suggest that the anticonvulsants tested do not lead to significant derangements in the metabolism of Mn.  相似文献   
958.
Recently there have been claims among drug users that some herbal drinks interfere with urinalysis for drugs of abuse and yield false positive results. Proof of such claims has yet to be shown. Screening for drugs of abuse is usually carried out using fluorescence polarization immunoassay (FPIA) or thin-layer chromatography (TLC). Fifty herbal samples which are considered among the most purchased herbs in the consumer market were used to investigate such claims. The drug groups that were tested for included amphetamines, opiates, barbiturates, cocaine metabolite, methadone, and their analogs. The herbs were analyzed at different concentrations (0.1, 1, 3, and 5 g/100 mL of distilled water) using TLC and FPIA to determine if any interfere with urinalysis for drugs of abuse and yield false positive results. For the FPIA test, the sample infusions were analyzed directly using the automated ADX analyzer (Abbott Laboratory). For TLC, infusions of the herbs were added to a solid-phase extraction column (pH 9.25), then extracted with a methylene chloride-isopropanol solvent system. At this pH, neutral, basic, and acidic drugs of abuse are extractable. The developed chromatographic plates were sprayed sequentially with several reagents. None of the herbs in the concentration ranges screened showed any interference with TLC or FPIA, indicating the invalidity of such claims.  相似文献   
959.
BACKGROUND: The Optimal management of common bile duct stones in patients undergoing laparoscopic cholecystectomy remains controversial. METHODS: A prospective study was conducted in 145 of the 481 patients who had a preoperative endoscopic retrograde cholangiogram before their laparoscopic cholecystectomy. RESULTS: Endoscopic retrograde cholangiogram was successful in 138 patients (95%), and common duct calculi were found in 72 (50%) of them. Endoscopic sphincterotomy with ductal clearance was achieved in 62 of 67 patients during a mean of 1.4 sessions (range, 1 to 5). Five (3.4%) patients had complications after endoscopic intervention, all of which resolved uneventfully . Fourteen patients underwent laparoscopic common duct exploration, five had failed endoscopic extraction, five had their common duct stones left intentionally for laparoscopic intervention, and, in addition, four of the seven patients who had a failed endoscopic retrograde cholangiogram had stones identified by intraoperative cholangiogram. Ten of these 14 patients underwent a successful laparoscopic common duct exploration. Laparoscopic cholecystectomy was successfully completed in 134 of the 145 patients, and none had major intraoperative or postoperative complications. The mean postoperative stay was 2.7 days for those patients who underwent a successful laparoscopic procedure. The overall mean number of admissions for completing the treatment was 2.3. CONCLUSIONS: Combined laparoscopic and endoscopic approach is a viable option for patients with gallstones and choledocholithiasis.  相似文献   
960.
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