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41.
Background: The lack of depth perception and spatial orientation in video vision are the drawbacks of laparoscopic surgery. The advent of a three-dimensional camera system enables surgeons to regain binocular vision and may be advantageous in complex laparoscopic procedures. Methods: We prospectively studied two groups of surgeons (with and without experiences in laparoscopic surgery) who performed a designated standardized laparoscopic task using a two-dimensional camera system (Olympus OTV-S4) vs a three-dimensional camera system (Baxter-V. Mueller VS7700) and compared their time performances. Results: The results suggested that only experience in laparoscopic surgery had significant effect on individual's performance. We could not demonstrate any superiority of the 3D system over the 2D system. However, two-thirds of the surgeons commented that the depth perception did improve. Conclusions: With further refinement of the technology, the 3D system may improve its potential in laparoscopic surgery.  相似文献   
42.
We reviewed 488 twin pregnancies that resulted in the birth of neonates weighing 1000 g or more. Complications were present in 56.7% of all pregnancies; most common were threat of premature labor (17.4%) and preeclampsia (14.5%). Perinatal mortality was 31.8 per thousand. Eighty percent of neonatal deaths in twin pregnancies involved newborns weighing less than 2000 g. Twin pregnancies are high risk pregnancies and benefit from early diagnosis, prevention and treatment of the threat of premature birth.  相似文献   
43.
Cognitive theory holds that dysfunctionalattitudes are important risk factors for depression.Critics have questioned this view, noting that, althoughdysfunctional attitudes are elevated in depression, they are not evident in vulnerable individualswho are asymptomatic. To deal with this criticism,Miranda and Persons (1988) have advanced the mood-statedependent hypothesis, which suggests that cognitive vulnerability factors are indeed present invulnerable individuals, but remain dormant untilactivated by negative mood. To test this hypothesis, 33women with and 67 women without histories of depression reported dysfunctional attitudes before andafter a film negative mood induction. As predicted,vulnerable subjects who reported increased negative moodreported increased dysfunctional attitudes.Unexpectedly, nonvulnerable subjects who reported increasednegative mood reported decreased dysfunctionalattitudes. These findings support the mood-statedependent hypothesis, and suggest that a deficit in theability to regulate negative emotions may be animportant feature of vulnerability todepression.  相似文献   
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Intravesical immunotherapy with bacillus Calmette-Guerin (BCG), Corynebacterium parvum (CP), keyhole limpet hemocyanin (KLH), and an extract of Allium sativum (AS) was studied in mice transplanted intravesically with mouse bladder tumor cells (MBT-2). Female C3H/He mice were anesthetized with sodium pentobarbital. Two X 10(5) MBT-2 cells were delivered into the bladder transurethrally using a small catheter, immediately after the posterior wall of the bladder had been electrocauterized. Bladder tumor became palpable or demonstrable microscopically in two weeks. Immunotherapy with BCG (2 X 10(6) CFU), CP (250 micrograms), KLH (50 micrograms), or AS (25 mg) was administered directly into the bladder via urethral catheter on day 1, day 6, or days 1 and 6. On day 21 the bladders and spleens were excised and weighed, and the bladders were examined macroscopically and microscopically for evidence of tumor. The results of the study showed that two treatments given one and six days after tumor transplant yielded the lowest tumor incidence and that CP and AS appeared equally effective or even slightly more effective than BCG in this model. These results suggest that clinical evaluation of CP or AS may be worthwhile.  相似文献   
47.
The effect of aqueous garlic extract on the macromolecular synthesis of Candida albicans was studied. Protein and nucleic acid syntheses were inhibited to the same extent as growth, but lipid synthesis was completely arrested. Blockage of lipid synthesis is likely an important component of the anticandidal activity of garlic.  相似文献   
48.
A prospective randomised clinical trial was conducted to examine the efficacy of 2 weeks pre-operative parenteral nutrition (PPN) for the prevention of complications following surgery for oesophageal cancer. Forty patients were studied, the diet of twenty being supplemented by pre-operative parenteral nutrition. There were no significant differences in age, nutritional status, tumour staging and histology between the two groups of patients. The use of PPN resulted in a significant gain in body weight and nitrogen but failed to produce an overall reduction in post-operative morbidity and mortality rates. However patients receiving PPN exhibited two types of changes in serum albumin levels. Those with a fall in serum albumin levels associated with an increase in body weight (indicating an expansion of extracellular volume) had a significantly higher incidence of post-operative pulmonary complications than the group exhibiting a rise in serum albumin levels concomitant with increase in body weight. These data suggested that two weeks PPN might not be adequate in certain patients and a longer period of PPN is required. They also show no clinical benefit from the routine use of pre-operative parenteral nutrition in all patients, but do not exclude benefit in selected groups.  相似文献   
49.
The virulence genotype profile and presence of a pathogenicity island(s) (PAI) were studied in 18 strains of F165-positive Escherichia coli originally isolated from diseased calves or piglets. On the basis of their adhesion phenotypes and genotypes, these extraintestinal pathogenic strains were classified into three groups. The F165 fimbrial complex consists of at least two serologically and genetically distinct fimbriae: F165(1) and F165(2). F165(1) is encoded by the foo operon (pap-like), and F165(2) is encoded by fot (sfa related). Strains in group 1 were foo and fot positive, strains in group 2 were foo and afa positive, and strains in group 3 were foo positive only. The strains were tested for the presence of virulence genes found mainly in extraintestinal pathogenic E. coli (ExPEC) strains. Although all the strains were positive for the papA variant encoding F11 fimbriae incD, traT, and papC, the prevalence of virulence genes commonly found in PAIs associated with ExPEC strains was highly variable, with strains of group 2 harboring most of the virulence genes tested. papG allele III was detected in all strains in group 1 and in one strain in group 3. All other strains were negative for the known alleles encoding PapG adhesins. The association of virulence genes with tRNA genes was characterized in these strains by using pulsed-field gel electrophoresis and DNA hybridization. The insertion site of the foo operon was found at the pheU tRNA locus in 16 of the 18 strains and at the selC tRNA locus in the other 2 strains. Furthermore, 8 of the 18 strains harbored a high-pathogenicity island which was inserted in either the asnT or the asnV/U tRNA locus. These results suggest the presence of one or more PAIs in septicemic strains from animals and the association of the foo operon with at least one of these islands. F165-positive strains share certain virulence traits with ExPEC, and most of them are pathogenic in piglets, as tested in experimental infections.  相似文献   
50.
A cross-sectional survey in individuals affected with the lysosomal storage disease Mucopolysaccharidosis VI (MPS VI) was conducted to establish demographics, urinary glycosaminoglycan (GAG) levels, and clinical progression of the disease. The survey evaluated 121 bona fide MPS VI-affected individuals over the age of 4 years from 15 countries across the Americas, Europe, and Australasia representing greater than 10% of the estimated world prevalence of the disease. A medical history, complete physical exam, urinary GAG determination, and assessment of several clinical measures related to physical endurance, pulmonary function, joint range of motion, strength, and quality of life were completed for each participant. Although a wide variation in clinical presentation was observed, several general findings were obtained reflecting progression of the disease. Impaired physical endurance, as measured by the distance achieved in a 6-min walk, could be demonstrated across all age groups of MPS VI-affected individuals. High urinary GAG values (>200 mug/mg creatinine) were associated with an accelerated clinical course comprised of age-adjusted short stature and low body weight, impaired endurance, compromised pulmonary function, and reduced joint range of motion. An unexpected result was the predominance of urinary GAG values <100 mug/mg creatinine for those participants over the age of 20 years. Pending the collection of longitudinal data, these results suggest that urinary GAG levels predict clinical morbidity, and longer-term survival is associated with urinary GAG levels below a threshold of 100 mug/mg creatinine.  相似文献   
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