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81.
The disinfection activity of a new multipurpose disinfection solution (OPTI-FREE Express with ALDOX) was compared to several other contact lens disinfecting solutions. The new solution is preserved with polyquaternium-1 and myristamidopropyl dimethylamine. The other solutions included 3% hydrogen peroxide systems and multipurpose solutions (MPS) preserved with polyhexamethylene biguanide. The products were tested for antimicrobial activity against Staphylococcus spp., Pseudomonas aeruginosa, Serratia marcescens, Candida albicans, Fusarium solani, and Aspergillus fumigatus. OPTI-FREE Express provided a broader range of antimicrobial activity than the MPS. It provided activity similar to that demonstrated by 3% hydrogen peroxide systems, but unlike the hydrogen peroxide system tested, it also prevented re growth of the organisms during extended storage.  相似文献   
82.
In this work, we study the thermal and optical properties of ion-doped phosphates glasses using the thermal lens (TL) technique. Three samples were characterized: Nd3+-doped Q-98; Nd3+-doped Q-100; and Yb3+-doped QX. We report multiwavelength TL measurements for a more accuracy determination of the fluorescence quantum efficiency and temperature coefficient of the optical path length change (ds/dT). In Nd-doped glasses, it was carried out using four discrete excitation wavelengths (between 514 and 872 nm) chosen to match with the ion absorption lines. In Yb-doped glass, the spectrum of heat generated along the Yb3+ transition (2 F 5/2rarr2 F 7/2) was obtained. In addition, parameters as thermal diffusivity and conductivity, thermal loading, etc were achieved. The advantages to obtain fluorescence quantum efficiency using the TL technique, mainly in Yb3+ doped materials, which are normally overestimated due to radiation trapping effect, are presented. The accuracy knowledge of these parameters is very important for design of high-power solid-state lasers, since these properties are directly related to the heat generation.  相似文献   
83.
We determined the effects of feeding canola oil or infusing it into the abomasum on rumen fermentation, nutrient digestibility, duodenal flows of fatty acids, and milk composition in Holstein cows. Five ruminally and duodenally cannulated Holstein cows in late lactation were used in a 3 x 5 incomplete Latin square design. Treatments were 1) Control: basal diet (CON), 2) Control+supplementation of canola oil at 1 kg/d in the feed (FED), and 3) Control+abomasal infusion of canola oil at 1 kg/d (INF). Compared with CON, feed intake, ruminal fermentation characteristics, ruminal and total tract digestibilities of nutrients were not significantly affected by FED treatment but duodenal flows and milk concentrations of fatty acids (FA) such as trans-11 18:1 and cis-9 trans-11 18:2 (conjugated linoleic acid, CLA) were increased. In contrast to the effects of FED, INF reduced feed intake, total VFA production, intestinal flows of nutrients, FA digestibility and yields of milk and milk fat. Both FED and INF significantly reduced the proportions of saturated and medium-chain FA, and increased cis 18:1 in milk. Concentrations of 18:2n-6 and 18:3n-3 in milk were increased nearly 2-fold with INF relative to CON. Dietary or postruminal supplementation of canola oil to late-lactation cows reduced saturated FA and increased unsaturated C18 in milk but nutrient digestion was adversely affected with abomasal infusion of canola oil.  相似文献   
84.
85.
OBJECTIVES: This study sought to present evidence that fast atrioventricular (AV) node pathways with posterior exit sites may participate in typical AV node reentry. BACKGROUND: Catheter ablation of the slow AV node pathway in the posteroseptal right atrium is the preferred therapeutic approach in patients with AV node reentrant tachycardia. Despite the success achieved with this approach, electrophysiologic changes consistent with fast pathway ablation are occasionally observed. One potential explanation is the presence of an aberrant posterior fast pathway. METHODS: The location of fast and slow AV node pathways was determined by atrial activation mapping along the tricuspid valve annulus during tachycardia and was further confirmed by the effect of radiofrequency catheter ablation. RESULTS: Seven patients with AV node reentrant tachycardia had evidence of a posterior fast pathway near the coronary sinus os. Abolition of anterograde and retrograde fast pathway conduction followed radiofrequency ablation in the posteroseptal region in six patients. Consistent with fast pathway ablation, the AH interval increased from 70 +/- 24 to 195 +/- 35 ms (mean +/- SD), and tachycardia was no longer inducible. Selective slow pathway ablation was performed in one other patient with a posterior fast pathway. CONCLUSIONS: Functionally fast AV node pathways may be located in the posteroseptal right atrium, where slow pathway modification is performed. These data delineate the limitation of an anatomically guided slow pathway ablative approach and emphasize the importance of detailed mapping and localization of the retrograde fast pathway exit site before ablation. Failure to recognize the presence of posterior fast AV node pathways may account for sporadic examples of AV block, complicating posteroseptal ablation in patients with AV node reentry.  相似文献   
86.
People with Alzheimer's disease living in a defined community in New York City were identified and assessed on two occasions to determine the number of hours of activities of daily living (ADL) care they received. Nearly half received all care hours from informal sources; however, a quarter received all ADL care hours from formal sources. The mean number of daily ADL hours in the sample was 9.7, of which 4.2 came from formal sources. This reflects the extensive use of Medicaid-based home care services in New York City. As dementia worsened, substitution of formal for informal care was rare, but formal care assumed a greater proportion of total care hours.  相似文献   
87.
OBJECTIVE: To evaluate the efficacy of unreamed retrograde intramedullary (IM) nailing of fractures of the femoral shaft in a second series of patients using modifications suggested from our initial study. DESIGN: Prospective. SETTING: Level I trauma center. METHODS: Based on the findings of a previous study, we began a clinical series incorporating changes consisting of (a) inclusion of any patient with a femoral shaft fracture amenable to IM nailing (i.e., closed physes), (b) primary use of a split patellar tendon intercondylar distal femoral entry portal, and (c) the use of a full-length femoral implant having variable size availability and dynamization capability. Over a twelve-month period, thirty-four patients with thirty-five femoral shaft fractures were treated. The protocol called for planned dynamization in statically locked stable fractures and unstable fractures showing minimal healing at six to twelve weeks. Functional outcome was assessed by using the Knee Society clinical rating system. RESULTS: Incorporating the concepts of canal fill and early dynamization, there were only two nonunions (6 percent) in this series as compared with 14 percent in the previously reported series with an overall shorter time to union (12.6 versus 15 weeks). There were no infections or malunions. Postoperative complaints of knee pain were minimal (knee score average: 98 points) and knee function was excellent (knee score average: 97 points). CONCLUSIONS: Although not advocated as a replacement for other techniques, unreamed retrograde nailing is presented as a safe and beneficial fracture fixation method that should be added to the orthopaedic surgeon's treatment armamentarium. The operative technique is quick and simple, and blood loss is minimal. Early nail dynamization and early weight-bearing are important in minimizing the risk of nonunion.  相似文献   
88.
Although sarcoidosis is predominantly a pulmonary disorder, it often produces disease in the head and neck. For this reason, otolaryngologists should be comfortable in evaluating and treating the disease. The diagnosis of sarcoidosis often can be made with a biopsy of conjunctival or oral mucosa, even when disease manifestations are not apparent in those parts of the body. In a case of sarcoidosis involving the nose, a 54-year-old black man had a proliferation of small lumps on the tip of his nose. For many years, he had had daily epistaxis, anosmia and severe difficulty breathing through this nose. The bridge of his nose was deformed, and he had a large anterior septal perforation. Physical examination revealed palpable bilateral cervical lymphadenopathy. Laboratory test results were, for the most part, normal; however, fine-needle aspiration of one of the cervical lymph nodes showed multiple epithelioid granulomas with interspersed lymphocyte, and an incisional biopsy of the nasal tissue was highly suggestive of sarcoidosis. Unenhanced computed tomography also revealed widespread nasal inflammation and an abnormal soft tissue mass anterior to the maxilla consistent with chronic osteomyelitis. The patient's condition dramatically improved following treatment with oral prednisone; however, he considered undergoing reconstructive surgery for the noticeable nasal septal deformity.  相似文献   
89.
BACKGROUND: Controversies over the frequency and intensity of the follow-up care of breast cancer patients exist. Some physicians have adopted an intensive approach to follow-up care that consists of frequent laboratory tests and routine imaging studies, including chest radiographs, bone scans, and CT scans, whereas others have established a minimalist approach consisting of only history, physical examinations, and mammograms. OBJECTIVES: Our objective was to evaluate the role of intensive follow-up on detection of breast cancer recurrence and to examine the impact of follow-up on overall survival. METHODS: During a 10-year period (1986-1996), 129 patients with recurrent disease were identified from a prospective database of 1898 breast cancer patients. The patients with recurrent disease were divided into minimalist or intensive groups according to method of detection. RESULTS: Twenty-seven of 126 (21%) patients were assigned to the intensive method of detection group (LFT, CEA, CA 15-3, chest radiograph, CT scan, and bone scan); 99 of 126 (79%) patients were assigned to the minimal detection group (history, physical examination, and mammography). Distant disease to the bone was the most common initial tumor recurrence, at 27%. History, physical examination, and mammography detected recurrent cancer in approximately the same amount of time as LFTs, tumor markers, CT scans, and chest radiographs (P = .960). When the recurrent patients were divided into intensive and minimalist groups and analyzed by time to detection of recurrence, there was no significant difference between the time to detection in those recurrences detected by intensive methods and those recurrences detected by minimalist methods (P = .95). The independent variables age, tumor size, type of surgery, number of positive nodes, time to recurrence, method of detection, and site of recurrence (regional or distant) were subject to univariate and multivariate analysis by the Cox proportional hazards model. Only two variables had an impact on survival by multivariate analysis: early timing of the recurrence (P = .0011) and the site of the recurrence (P = .02). Timing was defined as early (< or =365 days from the time of diagnosis to recurrence) or late (> or =365 days from the time of diagnosis to recurrence). Early recurrence was the first variable found to be significant on stepwise forward regression analysis. The primary site of recurrence was significant at step two. The method of detection--intensive or minimal--did not significantly affect survival (P = .18). CONCLUSIONS: There is no survival benefit to routine intensive follow-up regimens in detecting recurrent breast cancer. Expensive diagnostic tests such as bone scans, CT scans, and serial tumor markers are best used for detection of metastasis in symptomatic patients.  相似文献   
90.
The excitatory and inhibitory conductances driving the light-evoked currents (LECs) of cat and ferret ON- and OFF-center X ganglion cells were examined in sliced and isolated retina preparations using center spot stimulation in tetrodotoxin (TTX)-containing Ringer. ON-center X ganglion cells showed an increase in an excitatory conductance reversed positive to +20 mV during the spot stimulus. At spot offset, a transient inhibitory conductance was activated on many cells that reversed near ECl. OFF-center X ganglion cells showed increases in a sustained inhibitory conductance that reversed near ECl during spot stimulation. At spot offset, an excitatory conductance was activated that reversed positive to +20 mV. The light-evoked current kinetics of ON- and OFF-center X cells to spot stimulation did not significantly differ in form from their Y cell counterparts in TTX Ringer. When inhibition was blocked, current-voltage relations of the light-evoked excitatory postsynaptic currents (EPSCs) of both ON- and OFF-X cells were L-shaped and reversed near 0 mV. The EPSCs averaged between 300 and 500 pA at -80 mV. The metabotropic glutamate receptor agonist 2-amino-4-phosphonobutyric acid (APB), was used to block ON-center bipolar cell function. The LECs of ON-X ganglion cells were totally blocked in APB at all holding potentials. APB caused prominent reductions in the dark holding current and synaptic noise of ON-X cells. In contrast, the LECs of OFF-X ganglion cells remained in APB. An increase in the dark holding current was observed. The excitatory amino acid receptor antagonist combination of D-amino-5-phosphono-pentanoic acid (D-AP5) and 2, 3-dihydroxy-6-nitro-7-sulfamoyl-benzo-(F)-quinoxalinedione (NBQX) was used to block ionotropic glutamate receptor retinal neurotransmission. The LECs of all ON-X ganglion cells were totally blocked, and their holding currents were reduced similar to the actions of APB. For OFF-X ganglion cells, the antagonist combination always blocked the excitatory current at light-OFF; however, in many cells, the inhibitory current at light-ON remained. ON-center X ganglion cells receive active excitation during center illumination, and a transient inhibition at light-OFF. In contrast OFF-center X ganglion cells experience a sustained active inhibition during center illumination, and a shorter increase in excitation at light-offset. Cone bipolar cells provide a resting level of glutamate release on X ganglion cells on which their light-evoked currents are superimposed [corrected].  相似文献   
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