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1.
The 20q13 region harboring recently described putative oncogenes is frequently amplified in invasive ductal carcinoma (IDC). The aim of this study was to examine the 20q13 copy number in intraduct hyperplasia (IH), atypical duct hyperplasia (ADH), and ductal carcinoma in situ (DCIS) adjacent to IDC. In 5 patients, comparative genomic hybridization (CGH) after laser microdissection revealed 20q13 amplification in four of five cases of IH, in all of three cases of IH with atypia, all five of DCIS, and all five of IDC. Fluorescence in situ hybridization (FISH) confirmed the amplification at 20q13.2 in IH in the two specimens analyzed. The amplification rate, however, was higher in DCIS and IDC. In phenotypically normal ductal epithelium normal values were found for 20q13 copy number by FISH (n=2) and CGH (n=5). Although the number of cases presented here is small, our results suggest that mutations in the 20q13.2 region in IH may be associated with accelerated proliferation and hyperplasia of the ductal epithelium. Progression to DCIS and ICD is accompanied by a further increase in the 20q13.2 copy number. Received: 17 March 1999 / Accepted: 22 June 1999  相似文献   
2.
There are contradictory reports regarding the effects of inhalation anesthetics on the immune system. Measurable immune responses have been studied in vitro, but little is known about the in vivo effects in the intact organism. We used an attenuated, non-neuroinvasive, nonlethal strain of the encephalitic West Nile virus, termed WN-25, which can become lethal in combination with environmental stressors, to study possible modulatory immune effects of inhalation anesthetics in mice. Both single short-term exposure and repeated exposure to halothane and nitrous oxide were studied. Exposure to 30% CO2 served as a positive control. Mortality, brain invasion, spleen weight, and antiviral antibodies served as the experimental endpoints. Halothane and nitrous oxide led to viral brain invasion, increased mortality, and suppressed immune response in a concentration- and time-dependent manner. Repeated exposures had a cumulative effect. Assessment of the stability of the viral attenuation did not demonstrate any alteration in the character of the virus, suggesting an increased access to the brain by inhalation anesthetics that led to the fatal encephalitis. These findings may be of special concern to populations at risk, such as operating room staff and patients undergoing general anesthesia in endemic areas of encephalitic virus species, in which subclinical infection may develop into an overt disease.  相似文献   
3.
BackgroundAs the Center for Medicare and Medicaid (CMS) moves toward bundled payment plans for total joint arthroplasty (TJA), it becomes necessary to reduce factors that increase cost for an episode of care such as readmissions. The goal of this study is to evaluate the payment for observation stay versus readmission for patients who present to the emergency department.MethodsA retrospective review from 2014-2019 was conducted identifying all Medicare patients who had a primary, elective TJA and visited the ED within 90 days postoperatively. If a readmission was one midnight or less or had an equivalent diagnosis to an observation stay patient, it was characterized as a readmission that could have qualified as an observation stay. Using our institution’s average payment for Medicare readmissions and observations, actual and potential savings were calculated.ResultsSixty-nine out of 523 (13.2%) patients were placed under observation, while 454 (86.8%) patients were readmitted. Eighty-six out of 523 (18.9%) patients qualified for observation status. There was an actual savings of 11.8% by placing patients on observation status and readmission rate was decreased by 13.2%. Savings could have increased by a total of 27.7% and readmissions decreased by a total of 29.6% if all patients who qualified had been placed on observation status.ConclusionAt our institution, the implementation of observation stay has led to a savings of 11.8% and a potential total savings of 27.7%. The rate of readmissions was decreased by 13.2% and had the potential to decrease by a total of 29.6%.  相似文献   
4.
PurposeFractures of the femoral shaft in children are common. The rates of bone growth and remodeling in children vary according to their ages, which affect their respective management. MethodsThis paper evaluates the incidence and patterns of pediatric femoral shaft fracture and the current concepts of treatments available.ResultsThe type of fracture—closed or open; stable or unstable—needs to be taken into account. Child abuse should be suspected in fractures sustained by infants. For younger children, non-surgical management is preferred, which include Pavlik harness (< 6 months old) and early spica casting (6 months to 6 years old). Older children (> 6 years old) usually benefit from surgical treatments as outcomes of non-surgical alternatives are worse and are associated with prolonged recovery times. These operative measures for older children that are 6–12 years old include elastic stable intramedullary nailing and submuscular plating. Factors to be considered when devising an appropriate intervention include body mass, location of injury, and nature of fracture. For adolescent and skeletally mature teenagers (> 12 years old), rigid antegrade entry intramedullary fixation is indicated. In the event of open fractures or polytrauma, external fixation should be considered as a temporary treatment method for initial fracture stabilization.ConclusionAn age-based and evidence-based algorithm has been proposed to guide surgeons in the process of evaluating an appropriate treatment.  相似文献   
5.
Electronic (e-)cigarettes have emerged in recent years as putative alternative to conventional tobacco cigarettes. These products do not contain typical carcinogens that are present in tobacco smoke, due to the lack of combustion. However, besides nicotine, hazards can also arise from other constituents of liquids, such as solvents, flavors, additives and contaminants. In this study, we have analyzed 28 liquids of seven manufacturers purchased in Germany. We confirm the presence of a wide range of flavors to enhance palatability. Although glycerol and propylene glycol were detected in all samples, these solvents had been replaced by ethylene glycol as dominant compound in five products. Ethylene glycol is associated with markedly enhanced toxicological hazards when compared to conventionally used glycerol and propylene glycol. Additional additives, such as coumarin and acetamide, that raise concerns for human health were detected in certain samples. Ten out of 28 products had been declared “free-of-nicotine” by the manufacturer. Among these ten, seven liquids were identified containing nicotine in the range of 0.1–15 µg/ml. This suggests that “carry over” of ingredients may occur during the production of cartridges. We have further analyzed the formation of carbonylic compounds in one widely distributed nicotine-free brand. Significant amounts of formaldehyde, acetaldehyde and propionaldehyde were only found at 150 °C by headspace GC–MS analysis. In addition, an enhanced formation of aldehydes was found in defined puff fractions, using an adopted machine smoking protocol. However, this effect was delayed and only observed during the last third of the smoking procedure. In the emissions of these fractions, which represent up to 40 % of total vapor volume, similar levels of formaldehyde were detected when compared to conventional tobacco cigarettes. By contrast, carbonylic compounds were hardly detectable in earlier collected fractions. Our data demonstrate the necessity of standardized machine smoking protocols to reliably address putative risks of e-cigarettes for consumers.  相似文献   
6.
Previous investigation demonstrated the potential of L-cysteine (L-Cys) at high concentrations to cause hypoglycemia in mice totally deprived of insulin. For further elucidation of the glucose-lowering mechanism, glucose uptake and quantity of glucose transporters (GLUTs 3 and 4) in mouse soleus muscle and C2C12 muscle cells, as well as in human SH-SY5Y neuroblastoma cells, were investigated. A marked enhancement of glucose uptake was demonstrated, peaking at 5.0 mM L-Cys in soleus muscle (P < 0.05) and SH-SY5Y cells (P < 0.001), respectively. In contrast, glucose uptake was not affected in the C2C12 muscle cells. Kinetic analysis of the SH-SY5Y glucose uptake showed a 2.5-fold increase in maximum transport velocity compared with controls (P < 0.001). In addition, both GLUT3 and GLUT4 levels were increased following exposure to L-Cys. Our findings point to a possible hypoglycemic effect of L-Cys.  相似文献   
7.
8.

Background

The episode-of-care concept promulgated by the federal government requires hospitals to assume the cost burden for all care rendered up to 30 days after discharge, including all readmissions occurring in that time. Although surgical site infections (SSIs) are a leading cause of readmission after total joint arthroplasties (TJA) and spine surgery, it is unclear whether these readmissions occur relative to the 30-day period.

Questions/Purposes

We determined whether (1) most readmissions for SSIs occurred in 30 days, (2) the type of procedure performed affected the timing of readmission, and (3) the type of infecting organism influenced the timing of readmission.

Methods

From our hospital database we identified 91 patients treated with elective TJAs and spine surgery from 2007 through 2010 who were readmitted with SSIs. Of the 91 patients, 46 had undergone spine surgery and 45 had TJAs. For each of these readmissions, we determined the type of surgery, the length of time from initial discharge to readmission, and the type of infecting organism.

Results

Readmissions after spine surgery were more likely to occur within 30 days of discharge (80.4% for spine, 58.3% for TJAs). In the TJA cohort, there was a trend toward readmissions occurring within 30 days of discharge more often in the THA subset. We identified no correlation between type of infecting organism and timing of readmission.

Conclusions

With the episode-of-care model, SSIs pose a substantial cost burden for hospitals since the majority would be included in the 30-day period included in the bundled reimbursement.  相似文献   
9.
The purpose of the current study was to establish measurement reliability in adults with Cerebral Palsy (CP), and to examine the feasibility and outcomes of an upper extremity strength training program (three times per week for 90 min each time). A control group design mixed with a prospective time series design for the intervention group was completed, including a pre-test, a post-test after a 12-week intervention period, and a follow-up in the intervention group after an additional 10-week period. Seventeen adults with CP with severe motor impairment took part in the study (10 in the intervention and seven in the control group). The test battery was comprised of wrist and hand dynamometry; dominant hand upper-extremity function measures (Jebsen Hand Function Test = JHFT, Minnesota Manual Dexterity Test = MMDT, and the Nine Hole Peg Test = NHPT); and activity of daily living with the Barthel Index.The results indicated that in both the control and the intervention groups, the strength tests exhibited good-to-excellent reliability during pre-test and post-test. The group comparison revealed that while in the pre-test no between-group differences existed, in the post-test the strength training group demonstrated significantly higher values in five out of eight strength measures, as well as in the MMDT. Discontinuing the program for eight weeks reversed the effects almost to baseline. In conclusion, the outcomes demonstrated the reliability of the assessments utilized in this study, as well as the feasibility of the strength training program, in adults with severe motor impairment due to CP.  相似文献   
10.
The purpose of this study was to explore the effect of two awareness activities on children's attitudes towards peers with a disability. The Children's Attitudes towards Peers with Disability scale including cognitive, behavioral and emotional subscales was administered before and after two types of short-term interventions. The first included 75 children from grades 7-9, who actively participated in the workshop simulating movement activities. The second intervention included 121 students of the 10th grade, who observed their peers participating in a wheelchair-basketball activity together with elite wheelchair-basketball players. Results indicated significant effects in the cognitive and behavioral domains. Post-test findings confirmed that intervention bridged the difference in the cognitive domain observed between those with and without previous contact at pretest.  相似文献   
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