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51.

Purpose

To directly compare the safety of fluoroscopic guided percutaneous thoracic pedicle screw placement between Caucasians and Asians.

Methods

This was a retrospective computerized tomography (CT) evaluation study of 880 fluoroscopic guided percutaneous pedicle screws. 440 screws were inserted in 73 European patients and 440 screws were inserted in 75 Asian patients. Screw perforations were classified into Grade 0: no violation; Grade 1: <2 mm perforation; Grade 2: 2–4 mm perforation; and Grade 3: >4 mm perforation. For anterior perforations, the pedicle perforations were classified into Grade 0: no violation, Grade 1: <4 mm perforation; Grade 2: 4–6 mm perforation; and Grade 3: >6 mm perforation.

Results

The inter-rater reliability was adequate with a kappa value of 0.83. The mean age of the study group was 58.3 ± 15.6 years. The indications for surgery were tumor (70.3 %), infection (18.2 %), trauma (6.8 %), osteoporotic fracture (2.7 %) and degenerative diseases (2.0 %). The overall screw perforation rate was 9.7 %, in Europeans 9.1 % and in Asians 10.2 % (p > 0.05). Grade 1 perforation rate was 8.4 %, Grade 2 was 1.2 % and Grade 3 was 0.1 % with no difference in the grade of perforations between Europeans and Asians (p > 0.05). The perforation rate was the highest in T1 (33.3 %), followed by T6 (14.5 %) and T4 (14.0 %). Majority of perforations occurred medially (43.5 %), followed by laterally (25.9 %), and anteriorly (23.5 %). There was no statistical significant difference (p > 0.05) in the perforation rates between right-sided pedicle screws and left-sided pedicle screws (R: 10.0 %, L: 9.3 %).

Conclusions

There were no statistical significant differences in the overall perforation rates, grades of perforations, direction of perforations for implantation of percutaneous thoracic pedicle screws insertion using fluoroscopic guidance between Europeans and Asians. The safety profile for this technique was comparable to the current reported perforation rates for conventional open pedicle screw technique.
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In a detailed study of inheritance of DNA sequence polymorphism in a large reference pedigree, an individual was identified with an apparent genetic recombination event within the human beta-globin gene cluster. Analysis of the haplotypes of relevant individuals within this pedigree suggested that the meiotic crossing-over event is likely to have occurred within a 19.8-kilobase-pair region of the beta-globin gene cluster. Analysis of other DNA markers closely linked to the beta-globin gene cluster--segment 12 of chromosome 11 (D11S12) and loci for insulin, the cellular oncogene c-Ha-ras, and preproparathyroid hormone--confirmed that a crossover event must have occurred within the region of chromosome 11 between D11S12 and the beta-globin gene cluster. It is suggested that the event observed has occurred within a DNA region compatible with recombinational "hot spots" suggested by population studies.  相似文献   
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We have isolated and characterized cDNA encoding a human 58-kDa protein kinase that is homologous to the cell division control (CDC) protein kinases. This protein kinase also contains a unique N-terminal domain that may potentially regulate its function. Due to its relatedness to p34CDC2, the human p58 cDNA was overexpressed in CHO cells to determine the effect on the cell cycle. Elevated expression of p58 in these cells resulted in prolonged late telophase and early G1 phase of the cell cycle. These p58 overexpressors showed a significantly increased frequency of tubulin midbodies as well as significant increases in mitotic abnormalities. Thus, proper regulation of p58 protein kinase is essential for normal cell cycle progression in these cells.  相似文献   
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Fine needle aspiration of the thyroid is suggested as an initial diagnostic procedure in the evaluation of thyroid nodules. Some proponents of the procedure, however, believe that fine needle aspiration should be restricted to centers in which each operator obtains at least 500 biopsy specimens annually. Reviewed were 155 biopsy specimens obtained over three and one-half years, and the sensitivity of fine needle aspiration was determined to be 100 percent, the specificity to be 47.4 percent, and the accuracy to be 73 percent. A review of the literature revealed the sensitivity in larger series to range between 92 and 98 percent, specificity to range between 52 and 99.5 percent, and accuracy to range between 56.1 and 91.3 percent. The surgical yield of carcinoma was 64 percent in patients evaluated with fine needle aspiration, whereas the yield was 26 percent in those who underwent surgery without fine needle aspiration. These results appear to justify the use of fine needle aspiration in the evaluation of nodular thyroid disease at average-sized health care centers.  相似文献   
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Many adolescents have chronic exposure to hazardous levels of alcohol. This is likely to be a significant predictor of health outcomes, including those related to immunity. We assessed substance use and biochemical immunological parameters in heavy drinking adolescents (meeting DSM-IV criteria for alcohol dependence) and light/nondrinking control adolescents in Cape Town. Lifetime alcohol dose, measured in standard units of alcohol, was orders of magnitude higher in alcohol-dependent (AD) participants than controls. All adolescent AD had a “weekends-only” style of alcohol consumption. The AD group was chosen to represent relatively “pure” AD, with minimal other drug use and no psychiatric diagnoses. With these narrow parameters in place, we found that AD adolescents were lymphopenic compared with controls, with significantly lower mean numbers of absolute circulating CD3+, CD4+, and CD8+ T-lymphocytes. On conclusion, we found that adolescent AD individuals with excessive alcohol intake, in a weekend binge-drinking style but without comorbid drug or psychiatric disorders, may be at increased risk of lymphopenia. This alcohol misuse may increase infectious disease susceptibility (including TB and HIV) by reducing immune system capabilities. Complex interactions of alcohol with other documented high-risk activities may further compound health risks.  相似文献   
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