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81.
Minimally invasive mitral valve surgery: from Port Access to fully robotic-assisted surgery 总被引:5,自引:0,他引:5
Currently, there is a growing interest in minimally invasive cardiac surgery, and despite early criticisms, it has become the preferred method of mitral valve repair and replacement in many institutions worldwide with excellent results. The interest in performing cardiac valve operations through minimal incisions was stimulated by Port Access technology and has evolved to include robotically assisted video-enhanced valve surgery. Robotic assistance has led to shorter operating times and represents an ideal tool to prepare for fully robotic-assisted cardiac procedures. This report will highlight minimally invasive mitral valve surgery with its evolution from Port Access techniques to fully robotic-assisted surgery. The nuances, strengths, and shortcomings, as well as the potential to enhance the valvular procedure, the promise to reduce hospital stay, earlier return to normal activity, less pain, better cosmesis, and the rethinking of surgical dogma that wide surgical exposure is essential for such complex intracardiac surgery are discussed. 相似文献
82.
83.
Salwa S. ELGENDI Sonya M. RASHAD Fatma H. MOHAMED Wafaa M. EL‐TOHAMY Ashraf A. EL‐SHAZLY Reda M. JELANY 《International journal of rheumatic diseases》2008,11(4):393-399
Background: Osteoporosis (OP) is a growing health problem not only in women but also in men. Subjects and methods: This study was carried out on 100 healthy men, age range 30–65 years (mean ± SD, 44.65 ± 8.3). All were randomly recruited from Assiut city during the period January 2005 to January 2006. Complete clinical history included occupational history, smoking habit, physical activity and calcium intake. Complete clinical examination and anthropometric measurments were done. Laboratory investigations for serum calcium, phosphorus and osteocalcin were performed. Bone mineral density (BMD) was measured by calcaneal ultrasound. Results: Sixty‐three percent of participants had normal BMD, 37% had low BMD, (26% had quantitative bone ultrasound [QUS] T‐score –1 to –2.5 and 11% had QUS T‐score ≤ –2.5). Smoking and low physical activity were risk factors for low BMD. Significant positive correlations were found between BMD and body mass index, serum calcium, and osteocalcin and negative correlation with phosphorus. We concluded that low BMD occurs with high frequency in Egyptian men. Smoking, physical inactivity and low body index are significant risk factors. Low serum calcium, low serum osteocalcin and high serum phosphorus are biochemical risk factors of low BMD in males. 相似文献
84.
Brunner G; Metz CN; Nguyen H; Gabrilove J; Patel SR; Davitz MA; Rifkin DB; Wilson EL 《Blood》1994,83(8):2115-2125
Basic fibroblast growth factor (bFGF) is a hematopoietic cytokine that stimulates stromal and stem cell growth. It binds to a glycosylphosphatidylinositol (GPI)-anchored heparan sulfate proteoglycan on human bone marrow (BM) stromal cells. The bFGF- proteoglycan complex is biologically active and is released by addition of exogenous phosphatidylinositol-specific phospholipase C. In this study, we show the presence of an endogenous GPI-specific phospholipase D (GPI-PLD) that releases the bFGF-binding heparan sulfate proteoglycan and the variant surface glycoprotein (a model GPI-anchored protein) from BM cultures. An involvement of proteases in this process is unlikely, because released proteoglycan contained the GPI anchor component, ethanol-amine, and protease inhibitors did not diminish the release. The mechanism of release is likely to involve a GPI-PLD and not a GPI-specific phospholipase C, because the release of variant surface glycoprotein did not reveal an epitope called the cross- reacting determinant that is exposed by phospholipase C-catalyzed GPI anchor cleavage. In addition, phosphatidic acid (which is specifically a product of GPI-PLD-catalyzed anchor cleavage) was generated during the spontaneous release of the GPI-anchored variant surface glycoprotein. We also detected GPI-PLD-specific enzyme activity and mRNA in BM cells. Therefore, we conclude that an endogenous GPI-PLD releases bFGF-heparan sulfate proteoglycan complexes from human BM cultures. This mechanism of GPI anchor cleavage could be relevant for mobilizing biologically active bFGF in BM. An endogenous GPI-PLD could also release other GPI-anchored proteins important for hematopoiesis and other physiologic processes. 相似文献
85.
The mean maximum nuclear diameter (Dmax) in 21 cases of non-Hodgkin's lymphoma (NHL) has been determined, using the Reichert-Jung (Kontron) MOP-AMO3 user-controlled image analyser. Nuclear diameters of high-grade malignancy NHL were found to be considerably greater than those of low-grade malignancy lymphomas, although there was some overlap of their ranges. These findings confirm objectively subjective estimates of nuclear size in NHL. The relative usefulness of the user-controlled (interactive) image analyser for the measurement of nuclei in tissue sections is compared with that of a fully automatic machine. 相似文献
86.
COX-2 inhibition with rofecoxib does not increase intestinal permeability in healthy subjects: a double blind crossover study comparing rofecoxib with placebo and indomethacin 总被引:5,自引:0,他引:5 下载免费PDF全文
BACKGROUND: Acute and chronic use of non-steroidal anti-inflammatory drugs can increase intestinal permeability. Rofecoxib, which selectively inhibits cyclooxygenase 2 (COX-2), is a novel anti-inflammatory drug with the potential to produce minimal gastrointestinal toxic effects while retaining clinical efficacy. AIMS: To assess the potential for rofecoxib to affect the intestine adversely, in comparison with placebo and indomethacin. SUBJECTS: Thirty nine healthy subjects (aged 24-30 years). METHOD: We performed a four period crossover trial to assess intestinal permeability before and after seven days of treatment. Permeability was measured by the urinary ratio of chromium-51 labelled ethylene diamine tetraacetate ((51)CrEDTA)/L-rhamnose (five hour collection). RESULTS: Indomethacin 50 mg three times daily produced greater increases in intestinal permeability compared with placebo or rofecoxib (25 or 50 mg) (p< or = 0.001); rofecoxib was not significantly different from placebo. Mean day 7 to baseline ratios (95% confidence intervals) for (51)CrEDTA/L-rhamnose were 0.97 (0.82, 1.16), 0.80 (0.68, 0.95), 0.98 (0.82, 1.17), and 1.53 (1.27, 1.85) for placebo, rofecoxib 25 mg, rofecoxib 50 mg, and indomethacin groups, respectively. Rofecoxib was generally well tolerated. CONCLUSION: In this study, treatment for one week with indomethacin 50 mg three times daily significantly increased intestinal permeability compared with placebo, while treatment with rofecoxib 25 mg or 50 mg daily did not. The absence of a significant effect of rofecoxib on intestinal permeability at doses at least twice those recommended to treat osteoarthritis was consistent with other studies that have demonstrated little or no injury to the gastrointestinal mucosa associated with rofecoxib therapy. 相似文献
87.
Boumsell L; Bernard A; Reinherz EL; Nadler LM; Ritz J; Coppin H; Richard Y; Dubertret L; Valensi F; Degos L; Lemerle J; Flandrin G; Dausset J; Schlossman SF 《Blood》1981,57(3):526-530
Tumor cells from eight adult patients with T-cell chronic malignancies were investigated with a series of monoclonal antibodies recognizing T- cell differentiation antigens. This series allowed definition of discrete subpopulations of mature T cells with functional specialization. All six patients with Sezary syndrome and one patient with T-chronic lymphocytic leukemia had cells with the same phenotype as normal helper/inducer T cells, whereas the other patient with T- chronic lymphocytic leukemia had cell with the same phenotype as normal cytotoxic/suppressor T cells. Some clinical manifestations observed in these patients may reflect retention of functional activities by their malignant cells. 相似文献
88.
Heterozygosity for a defective gene for CC chemokine receptor 5 is not the sole determinant for the immunologic and virologic phenotype of HIV-infected long-term nonprogressors. 下载免费PDF全文
O J Cohen M Vaccarezza G K Lam B F Baird K Wildt P M Murphy P A Zimmerman T B Nutman C H Fox S Hoover J Adelsberger M Baseler J Arthos R T Davey Jr R L Dewar J Metcalf D J Schwartzentruber J M Orenstein S Buchbinder A J Saah R Detels J Phair C Rinaldo J B Margolick A S Fauci et al. 《The Journal of clinical investigation》1997,100(6):1581-1589
HIV-1-infected long-term nonprogressors are a heterogeneous group of individuals with regard to immunologic and virologic markers of HIV-1 disease. CC chemokine receptor 5 (CCR5) has recently been identified as an important coreceptor for HIV-1 entry into CD4+ T cells. A mutant allele of CCR5 confers a high degree of resistance to HIV-1 infection in homozygous individuals and partial protection against HIV disease progression in heterozygotes. The frequency of CCR5 heterozygotes is increased among HIV-1- infected long-term nonprogressors compared with progressors; however, the host defense mechanisms responsible for nonprogression in CCR5 heterozygotes are unknown. We hypothesized that nonprogressors who were heterozygous for the mutant CCR5 gene might define a subgroup of nonprogressors with higher CD4+ T cell counts and lower viral load compared with CCR5 wild-type nonprogressors. However, in a cohort of 33 HIV-1-infected long-term nonprogressors, those who were heterozygous for the mutant CCR5 gene were indistinguishable from CCR5 wild-type nonprogressors with regard to all measured immunologic and virologic parameters. Although epidemiologic data support a role for the mutant CCR5 allele in the determination of the state of long-term nonprogression in some HIV-1- infected individuals, it is not the only determinant. Furthermore, long-term nonprogressors with the wild-type CCR5 genotype are indistinguishable from heterozygotes from an immunologic and virologic standpoint. 相似文献
89.
90.
Abdulbari BENER Omer F. EL‐RUFAIE Saadat KAMRAN Ana B. GEORGIEVSKI Abdulaziz FAROOQ Martin RYSAVY 《International journal of rheumatic diseases》2006,9(3):257-263
Objective: The aim of this study was to determine the prevalence of low back pain (LBP) in a primary care setting population and examine its association with the symptoms of depression and somatization. Methods: This is a cross‐sectional study, utilising a survey carried out in primary health care clinics (PHCs) in Al‐Ain, United Arab Emirates (UAE). A multistage stratified sampling design was used and a representative sample of 1304 UAE nationals aged 18–65 years who attended PHC clinics for any reason were included and 1103 (84.5%) subjects agreed to participate and responded to the questionnaire during a period from June 2001 to January 2002. A specially designed questionnaire with three parts was used for the data collection: socio‐demographic information of the studied subjects, modified version of the Roland‐Morris scale for evaluating back‐related functional disability and SCL‐90 R for depression and somatization subscales was used to assess depressive and somatic symptoms. Results: Of the total number of subjects surveyed (1103), 586 (53.1%) were men and 517 (46.9%) women. The mean age was 34.9 ± 13.4 years for men and 33.5 ± 11.8 years for women. The prevalence of LBP in the studied subjects was 64.7% (95% CI, 60.7–68.5] with 46.7% among men and 53.3% among women. There were a significant differences between the subjects with LBP and without LBP with respect to gender (P < 0.001), body mass index (BMI) (P < 0.001), occupational status (P < 0.001) and living environment (P = 0.016). Functional disability was higher in patients with LBP. Young patients in aged 15–34 years, patients with preparatory/secondary educational level and students showed higher depressive symptoms. A similar pattern was found in patients with somatic symptoms. Factor analysis revealed a strong association between depression and somatization in LBP patients. Conclusions: Functional disability was higher in with LBP. Furthermore, symptoms of depression and somatization are prevalent among LBP patients. 相似文献