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61.
62.
CVD 103-HgR is a live oral cholera vaccine strain constructed by deleting 94% of the gene for the enzymatically active A subunit of cholera toxin from classical Inaba Vibrio cholerae O1 569B; the strain also contains a mercury resistance gene as an identifying marker. This vaccine was well tolerated and immunogenic in double-blind, controlled studies and was protective in open-label studies of volunteers challenged with V. cholerae O1. A randomized, double-blind, placebo-controlled, multicenter study of vaccine efficacy was designed to test longer-term protection of CVD 103-HgR against moderate and severe El Tor cholera in U.S. volunteers. A total of 85 volunteers (50 at the University of Maryland and 35 at Children's Hospital Medical Center/University of Cincinnati) were recruited for vaccination and challenge with wild-type V. cholerae El Tor Inaba. Volunteers were randomized in a double-blind manner to receive, with buffer, a single oral dose of either CVD 103-HgR (2 x 10(8) to 8 x 10(8) CFU) or placebo (killed E. coli K-12). About 3 months after immunization, 51 of these volunteers were orally challenged with 10(5) CFU of virulent V. cholerae O1 El Tor Inaba strain N16961, prepared from a standardized frozen inoculum. Ninety-one percent of the vaccinees had a >/=4-fold rise in serum vibriocidal antibodies after vaccination. After challenge, 9 (39%) of the 23 placebo recipients and 1 (4%) of the 28 vaccinees had moderate or severe diarrhea (>/=3-liter diarrheal stool) (P < 0.01; protective efficacy, 91%). A total of 21 (91%) of 23 placebo recipients and 5 (18%) of 28 vaccinees had any diarrhea (P < 0.001; protective efficacy, 80%). Peak stool V. cholerae excretion among placebo recipients was 1.1 x 10(7) CFU/g and among vaccinees was 4.9 x 10(2) CFU/g (P < 0.001). This vaccine could therefore be a safe and effective tool to prevent cholera in travelers.  相似文献   
63.
The efficacy and safety of cetirizine were evaluated in 419 patients with seasonal allergic rhinitis. Using a 4-way, double-blind randomization schedule, patients were given a 1-week course of once daily cetirizine (5, 10, or 20 mg) or placebo. Patient and physician efficacy ratings corresponded, indicating superiority of cetirizine to placebo (P less than .05) in reducing symptom severity scores for sneezing, rhinorrhea, ocular pruritus, nasal pruritus, watering of the eyes, and redness of the eyes. All cetirizine doses achieved higher efficacy ratings (72.7%, 79.2%, and 75.7%, respectively) than placebo (52.9%; P less than .05) by the physician's global assessment. Cetirizine was well tolerated, with sedation being the most common adverse experience, increasing in frequency at higher doses. A dose-response relationship was evident for selected symptoms, and the once daily 5-mg dose was found to be an effective minimum dose.  相似文献   
64.
As part of the RTOG research effort in the treatment of advanced, inoperable squamous cancer of the head and neck region, the hypoxic cell sensitizer, misonidazole, was selected for investigation as an adjuvant to definitive irradiation. Based upon a pilot experience (78-02) showing a 67% complete response rate among 36 AJC Stage III-IV patients receiving full-dose irradiation and 6 weekly p.o. doses of misonidazole, a phase III trial was carried out from '79-'83. Three hundred and six patients were entered, 42% of whom had oropharyngeal primaries and with 78% of all cases representing T3 or T4 (inoperable) lesions. Only 16% of the entire series presented with N0 necks. Fractionation was altered among the misonidazole-receiving patients, in contrast to "standard" 5 treatments per week among "control" patients, such that 2 separate treatments were given on each day of p.o. misonidazole administration (2.0 gm/m2/wk X 6 doses, 2.5 Gy in a.m., 2.1 Gy in p.m.). Total tumor doses were identical among the two treatment arms except that a limitation of 40.0 Gy to spinal cord was specified for sensitized radiotherapy vs. 45.0 Gy for "control" patients. Primary tumor clearance was observed to be 55-60%, with minor variations according to tumor stage and site. The local regional control rate among radiotherapy-alone patients was 26% at 2 years compared to 22% (2 years) within the misonidazole-receiving group. Analysis of survival revealed no advantage to the sensitized patients, with 55 +/- 2% surviving 1 year and 22 +/- 1% living 3 years following treatment in both treatment categories. Distant metastases as first site of failure (12-13%) and the local failure among initial complete responders (46%) showed no advantage to the misonidazole group. Although a misonidazole dosage of 2.0 gm/m2/wk X 6 (12 gm/m2 total) is well tolerated, no clinical benefit was demonstrated in this randomized trial. Other nitroimidazole analogs (e.g. SR-2508) are now being investigated.  相似文献   
65.
The prognostic relevance of phytohemagglutinin (PHA) and purified protein derivative (PPD) lymphocyte reactivity at diagnosis and after radiotherapy was evaluated in breast cancer patients. The patients were followed up to 13 years and the prognostic value expressed as ratios between observed number of deaths and "estimated" number of deaths under the null hypothesis. There was no significant association between the initial PHA and PPD reactivity and the survival of the patients. On the other hand, mortality up to 8 years after radiotherapy was significantly higher for patients with low PHA and PPD reactivity at completion of treatment. Furthermore, patients who had higher than average PPD reactivity 6 to 10 months after radiotherapy, seemed to have a higher survival rate. The prognostic relevance of postirradiation lymphocyte reactivity was only to some extent explained by clinical stage.  相似文献   
66.
In the limestone quarries of Indiana, USA, pneumatic percussive hammers replaced the mallet and hammer around 1900. By 1917 the air hammer was being used exclusively for periods of eight to ten hours a shift. In 1918 Alice Hamilton investigated an unusual "disease" in these stonecutters of Bedford, Indiana, who complained of "attacks of numbness and blanching of the fingers coming on suddenly under the influence of cold and then disappearing." The prevalence of vibration induced white finger (VWF) found in this population of 38 stonecutters was 89%, with decreased light touch, pain, and temperature appreciation in advanced cases. In 1978 a VWF research team revisited these limestone quarries. During the 60 year interval the stonecutting industry had contracted from 4000 workers in 40 quarries in 1918 to 3-400 in 10 quarries in 1978, with only 50 employees remaining in the Bedford area. In a population of 30 stonecutters the prevalence of VWF in 1978 was 80%, with similar sensory loss in light touch, pain, and temperature appreciation. Between 1918 and 1978 no change had taken place in the design of the air hammers used for stonecutting. Vibration levels of 4859 metres/s2 on the chisel, and 2010 metres/s2 on the barrel were measured over a frequency range 6.3 to 1000 Hz. The fundamental frequency was 75 Hz. These measured vibration levels are outside the ISO/DIS/5349 (1979) recommended limits for human exposure to vibration transmitted to the hand. The VWF data presented in this paper, and those originally reported by Hamilton in 1918, call for an immediate redesign of stonecutting pneumatic hammers in order to remove one cause of Raynaud's phenomenon of occupational origin.  相似文献   
67.
The Journal of Behavioral Health Services & Research - Individuals recently released from jail or prison with serious mental illnesses may be vulnerable to the coronavirus pandemic. This study...  相似文献   
68.

This study is concerned with the determination of an optimal appointment schedule in an outpatient-inpatient hospital system where the inpatient exams can be cancelled based on certain rules while the outpatient exams cannot be cancelled. Stochastic programming models were formulated and solved to tackle the stochasticity in the procedure durations and patient arrival patterns. The first model, a two-stage stochastic programming model, is formulated to optimize the slot size. The second model further optimizes the inpatient block (IPB) placement and slot size simultaneously. A computational method is developed to solve the second optimization problem. A case study is conducted using the data from Magnetic Resonance Imaging (MRI) centers of Lahey Hospital and Medical Center (LHMC). The current schedule and the schedules obtained from the optimization models are evaluated and compared using simulation based on FlexSim Healthcare. Results indicate that the overall weighted cost can be reduced by 11.6% by optimizing the slot size and can be further reduced by an additional 12.6% by optimizing slot size and IPB placement simultaneously. Three commonly used sequencing rules (IPBEG, OPBEG, and a variant of ALTER rule) were also evaluated. The results showed that when optimization tools are not available, ALTER variant which evenly distributes the IPBs across the day has the best performance. Sensitivity analysis of weights for patient waiting time, machine idle time and exam cancellations further supports the superiority of ALTER variant sequencing rules compared to the other sequencing methods. A Pareto frontier was also developed and presented between patient waiting time and machine idle time to enable medical centers with different priorities to obtain solutions that accurately reflect their respective optimal tradeoffs. An extended optimization model was also developed to incorporate the emergency patient arrivals. The optimal schedules from the extended model show only minor differences compared to those from the original model, thus proving the robustness of the scheduling solutions obtained from our optimal models against the impacts of emergency patient arrivals.

  相似文献   
69.
Ascending aortic pseudoaneurysms are rare, but life‐threatening conditions, that often require intervention. While endovascular techniques have advanced significantly, the majority of these clinical scenarios preclude endovascular options and the primary treatment modality remains open surgical repair. Repair of an aortic pseudoaneurysm eroding through the sternum resulting in a pulsatile chest wall mass is technically challenging. We report the successful repair of a large ascending aortic pseudoaneurysm in a 62‐year‐old male with bovine arch anatomy and prior Type A dissection repair, presenting with contained rupture and a pulsatile chest wall mass.  相似文献   
70.
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