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991.
Dunn Kelly E.; Sigmon Stacey C.; Reimann Edward F.; Badger Gary J.; Heil Sarah H.; Higgins Stephen T. 《Canadian Metallurgical Quarterly》2010,18(1):37
Prevalence of cigarette smoking among opioid-maintained patients is more than threefold that of the general population and associated with increased morbidity and mortality. Relatively few studies have evaluated smoking interventions in this population. The purpose of the present study was to examine the efficacy of contingency management for promoting initial smoking abstinence. Forty methadone- or buprenorphine-maintained cigarette smokers were randomly assigned to a contingent (n = 20) or noncontingent (n = 20) experimental group and visited the clinic for 14 consecutive days. Contingent participants received vouchers based on breath carbon monoxide levels during Study Days 1 to 5 and urinary cotinine levels during Days 6 to 14. Voucher earnings began at $9.00 and increased by $1.50 with each subsequent negative sample for maximum possible of $362.50. Noncontingent participants earned vouchers independent of smoking status. Although not a primary focus, participants who were interested and medically eligible could also receive bupropion (Zyban). Contingent participants achieved significantly more initial smoking abstinence, as evidenced by a greater percentage of smoking-negative samples (55% vs. 17%) and longer duration of continuous abstinence (7.7 vs. 2.4 days) during the 2 week quit attempt than noncontingent participants, respectively. Bupropion did not significantly influence abstinence outcomes. Results from this randomized clinical trial support the efficacy of contingency management interventions in promoting initial smoking abstinence in this challenging population. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
992.
993.
The investigation dealt with testing vitamins A,E,B1 and B2 levels in the blood of children residing in different regions of Ukraine. The existence of polyhypovitaminosis, especially in children suffering from gastrointestinal tract disease was displayed. 28% of the children may be attributed to a risk group. Some measures directed to polyhypovitaminosis elimination in children, residing in Ukraine, are proposed. 相似文献
994.
Liver transplantation is an immunological peculiarity with respect to the resistance of the graft to humoral rejection. We undertook a kinetic analysis of molecules involved in humoral rejection for a period of one week following xenografting in the hamster to rat model system. A complement-dependent lymphocytotoxicity test (CDC) was used to detect anti-donor antibodies in the recipient rats. Complement was studied by two methods. Function of the classical complement pathway was evaluated with a hemolytic assay, and C3 was measured by radial immunodiffusion. Conversion of the major plasma proteins from recipient to donor profile was studied by zone electrophoresis on agarose. CDC showed antibody titers rose during the first week post-transplantation, and they were of complement-activating isotypes. Zone electrophoresis showed almost complete replacement of rat C3 by hamster C3 within 72 hours. Hemolytic assay of complement on day 6 post-transplant showed serum of the xenograft recipients could lyse erythrocytes sensitized with rat antibody with 80% of efficiency of normal rat serum. Our data show the effector molecules for humoral rejection, rat antibodies with anti-hamster specificity and a functional complement cascade, were present within the first week following transplantation. Rapid conversion of serum complement to hamster proteins maintains compatibility with the species-specific membrane inhibitors of complement activation expressed by the xenografted hepatocytes, and could limit complement-mediated damage. 相似文献
995.
A family is presented in whom hereditary angioedema (HAE) and hereditary breast cancer were coexistent, an association not previously reported. A potential for genetic and treatment-related interactions between the two conditions exists. The use of the hormonal agent danazol to suppress HAE is unlikely to adversely affect the development or outcome of breast cancer. Surgery, chemotherapy, and radiotherapy were received by affected family members, without triggering edema. Whether hormonal breast cancer treatment affects the suppression of HAE by danazol remains unknown. 相似文献
996.
An eight-year-old neutered male domestic shorthair cat had a zygomatic salivary cyst with associated mucocele formation. A fluctuating swelling developed ventral to the right eye, causing bulging of the lower eyeild, and a corresponding swelling was present in the caudal vestibule of the oral cavity. Cytological examination of the fluid obtained from aspiration of the swelling was consistent with the appearance of saliva. A tentative diagnosis of zygomatic salivary mucocele was made. Surgical exploration and resection of the swelling demonstrated the presence of a multilobular cystic zygomatic salivary gland. The histopathological appearance of the resected tissue was interpreted as an inflammatory reaction to mucus derived from a multilocular salivary cyst. 相似文献
997.
Robertson M Amick BC DeRango K Rooney T Bazzani L Harrist R Moore A 《Applied ergonomics》2009,40(1):124-135
A large-scale field intervention study was undertaken to examine the effects of office ergonomics training coupled with a highly adjustable chair on office workers’ knowledge and musculoskeletal risks. Office workers were assigned to one of three study groups: a group receiving the training and adjustable chair (n=96), a training-only group (n=63), and a control group (n=57). The office ergonomics training program was created using an instructional systems design model. A pre/post-training knowledge test was administered to all those who attended the training. Body postures and workstation set-ups were observed before and after the intervention. Perceived control over the physical work environment was higher for both intervention groups as compared to workers in the control group. A significant increase in overall ergonomic knowledge was observed for the intervention groups. Both intervention groups exhibited higher level behavioral translation and had lower musculoskeletal risk than the control group. 相似文献
998.
Menéndez CC Amick BC Robertson M Bazzani L DeRango K Rooney T Moore A 《Applied ergonomics》2012,43(4):639-644
Objective
Examine the effects of two office ergonomics interventions in reducing visual symptoms at a private sector worksite.Methods
A quasi-experimental study design evaluated the effects of a highly adjustable chair with office ergonomics training intervention (CWT group) and the training only (TO group) compared with no intervention (CO group). Data collection occurred 2 and 1 month(s) pre-intervention and 2, 6 and 12 months post-intervention. During each data collection period, a work environment and health questionnaire (covariates) and daily health diary (outcomes) were completed. Multilevel statistical models tested hypotheses.Results
Both the training only intervention (p < 0.001) and the chair with training intervention (p = 0.01) reduced visual symptoms after 12 months.Conclusion
The office ergonomics training alone and coupled with a highly adjustable chair reduced visual symptoms. In replicating results from a public sector worksite at a private sector worksite the external validity of the interventions is strengthened, thus broadening its generalizability. 相似文献999.
The capability to produce X-ray masks inexpensively and rapidly is expected to greatly enhance the commercial appeal of the
LIGA process. This paper presents a process to fabricate X-ray masks both inexpensively (under $1000) and rapidly (within
a few days). The process involves one UV lithography step and eliminates the need for an intermediate X-ray mask. The X-ray
mask produced by this process consists of a 125 μm thick graphite membrane that supports a gold-on-nickel absorber pattern.
The thickness of the absorber structures is great enough to supply sufficient contrast even when radiation sources with high
characteristic photon energies up to 40 keV are utilized and/or when deep exposures are desired.
The mask fabrication process is initiated by spin coating 30–50 μm of SU-8 directly on a graphite membrane. The SU-8 is then
patterned using a UV mask. Gold-on-nickel absorber structures are electroplated directly onto the SU-8 covered graphite. Once
the remaining SU-8 is removed, attaching the graphite membrane to a frame completes the mask.
To test the performance of the mask, a nickel mold insert was fabricated. A sheet of PMMA 500 μm in thickness was bonded to
a nickel substrate, then exposed to X-rays through the mask, and developed. Electroplating nickel into the patterned PMMA
sheet produced a mold insert. SEM pictures taken of the SU-8, the X-ray mask, and the mold insert are shown. This method of
rapidly producing an inexpensive X-ray mask for LIGA resulted in a mold insert with smooth, vertical sidewalls whose dimensions
were within two micrometers of the UV mask dimensions.
Received: 12 December 1998/Accepted: 2 February 1999 相似文献
1000.
Injection molding of polymeric LIGA HARMs 总被引:1,自引:0,他引:1
The primary goal of an ongoing research effort at LSU is to develop the three-step LIGA process to inexpensively manufacture
high aspect ratio microstructures (HARMs). The first two steps of the process (lithography and electroplating) produce a metallic
mold insert that can be used as a template for molding microstructures. The final step of LIGA is molding. This paper focuses
on injection molding of thermoplastics to produce surfaces covered with HARMs. The resulting microstructures are hundreds
of micrometers in height, tens of micrometers in width, and separated by gaps on the order of tens of micrometers. Injection
molding experiments using high density polyethylene were performed using a commercially available injection molding machine.
Experimental variables included injection speed, the tool temperature, and air pressure in the mold cavity. Elevating the
tool temperature above the melting point ensured that the polymer completely filled the mold, producing microstructures with
the desired geometry. As the temperature of the mold was reduced, higher injection speeds did not necessarily ensure filling
of the mold cavity. The cycle time is shorter than the values previously reported in the literature [Madou (1996)].
Received: 30 March 1999 / Accepted: 12 April 1999 相似文献