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41.
42.

Purpose  

High-energy photons are most commonly used in radiotherapy to treat cancer. Wedge filters are required to obtain homogeneous dose distribution in the patient. Different wedge filter types create different surface doses. In this study, the effect of the virtual and physical wedge filters on the surface and build-up region doses was examined for 6- and 18-MV high-energy photon beams.  相似文献   
43.
The plantar areas of the foot have specific biomechanical characteristics and play a distinct role in balance and standing. For the forefoot surgeon, knowledge of the variations in the anatomy of communicating branches is important for plantar reconstruction, local injection therapy and an excision of interdigital neuroma. The anatomy of the communicating branches of the plantar nerves between the fourth and third common plantar digital nerves in the foot were studied in 50 adult men cadaveric feet. A communicating branch was present between the third and fourth intermetatarsal spaces nerves in all eight left feet and in six right feet (overall, 28%), and absent in 36 (72%). A communicating branch was found in 14 ft. Ten of the 14 communications were from the lateral to the medial plantar nerve. The length of the communicating branch ranged from 8 to 56 mm (average 16.4 mm) and its diameter was 0.2–0.6 times of the fourth common plantar digital nerve. The angle of the communicating branch with the common plantar digital nerve from which it originated was less than 30° in 11 ft, 30–59° in 27 ft, 60–80° in 8 ft, and more than 80° in 4 ft. Classification of the branch is based on the branching pattern of the communicating branch and explains variations in plantar sensory innervations. We think that the perpendicular coursing communicating branch is at higher risk to be severed during surgery.  相似文献   
44.

Objective

The aim of this study was to investigate bone protective effects of risedronate, atorvastatin, raloxifene and clomiphene citrate in ovariectomized rats.

Methods

Our study was conducted on 63 rats at Experimental Research Center of Celal Bayar University. Six-month-old rats were divided into seven groups. There were five drug administered ovariectomized groups, one ovariectomized control group without drug administration and one non-ovariectomized control group without drug administration. Eight weeks postovariectomy, rats were treated with the bisphosphonate risedronate sodium, the statin atorvastatin, the estrogen 17β-estradiol and the selective estrogen receptor modulators (SERMs) raloxifene hydrochloride and clomiphene citrate by gavage daily for 8 weeks. At the end of the study, rats were killed under anesthesia. For densitometric evaluation, left femurs and tibiae were removed. Left femurs were also used to measure bone volume. Right femurs were used for three-point bending test.

Results

Compared to ovariectomized group, femur cortex volume increased significantly in non-ovariectomized group (p = 0.016). Compared to non-ovariectomized group, distal femoral metaphyseal and femur midshaft bone mineral density values were significantly lower in ovariectomized group (p = 0.047). In ovariectomy + atorvastatin group, whole femur and femur midshaft bone mineral density and three-point bending test maximal load values were significantly higher than ovariectomized group (p = 0.049, 0.05, and 0.018). When compared to the ovariectomized group, no significant difference was found with respect to femoral maximum load values in groups treated with risedronate, estrogen, raloxifene and clomiphene (p = 0.602, 0.602, 0.75, and 0.927). In ovariectomy + risedronate group, femur midshaft bone mineral density values were significantly higher than the values in ovariectomized group (p = 0.023). When compared to ovariectomized group, no significant difference was found with respect to femur midshaft bone mineral density values in groups treated with estrogen, raloxifene and clomiphene (p = 0.306, 0.808, and 0.095).

Conclusions

While risedronate sodium prevented the decrease in bone mineral density in ovariectomized rats, atorvastatin maintained mechanical characteristics of bone and also prevented the decrease in bone mineral density as risedronate sodium.  相似文献   
45.
S S Bilge  J C Vary  Jr  S F Dowell    P I Tarr 《Infection and immunity》1996,64(11):4795-4801
Shiga-toxigenic Escherichia coli strains belonging to serotype O157 are important human pathogens, but the genetic basis of expression of the O157 antigen and the role played by the lipopolysaccharide O side chain in the adherence of this organism to epithelial cells are not understood. We performed TnphoA mutagenesis on E. coli O157:H7 strain 86-24 to identify a mutant (strain F12) deficient in O-antigen expression. Nucleotide sequence analysis demonstrated that the transposon inserted within an open reading frame with significant homology to rfbE of Vibrio cholerae O1 (U. H. Stroeher, L. E. Karageorgos, R. Morona, and P. A. Manning, Proc. Natl. Acad. Sci. USA 89:2566-2570, 1992), which is postulated to encode perosamine synthetase. This open reading frame was designated rfbE(EcO157:H7). The guanine-plus-cytosine fraction (0.35) suggests that rfbE(EcO157:H7) may have originated in a species other than E. coli. rfbE(EcO157:H7) is conserved in nontoxigenic E. coli O157 strains expressing a variety of other flagellar antigens but is not found in E. coli O55:H7 strains, which are more closely related to E. coli O157:H7. Strain F12 was significantly more adherent to HeLa cells in a quantitative adherence assay than was its E. coli O157:H7 parent, but they did not differ in other phenotypes. Restoration of the expression of the O side chain by complementation of the TnphoA mutation in strain F12 by a plasmid expressing intact rfbE(EcO157:H7) reduced the adherence of the hyperadherent strain F12. We conclude that rfbE(EcO157:H7) is necessary for the expression of the O157 antigen, that acquisition of E. coli rfb genes occurred independently in E. coli O157:H7 and unrelated O157 strains, and that the O side chain of E. coli O157:H7 lipopolysaccharide interferes with the adherence of E. coli O157:H7 to epithelial cells.  相似文献   
46.
Despite the reports of dysfunction of the lytic abilities of CD8(+) T cells during human immunodeficiency virus-1 (HIV-1) disease progression, the effects of infection on the noncytolytic functions of CD8(+) T cells have not been well characterized to date. We examined the effect of HIV-1 infection on the cytokine and chemokine responses of peripheral blood-derived CD8(+) T cells in an in vitro system. Activation of HIV-1-infected CD8(+) T cells with phytohemagglutinin resulted in a 4- to 8-fold increase in the production of macrophage inflammatory protein (MIP)-1α, MIP-1β, regulated on activation normal T-cell expressed and secreted, and interleukin (IL)-16. Treatment of activated HIV-1-infected CD8(+) T cells with anti-CD3 monoclonal (M) antibody (Ab) and IL-15 induced strong production of interferon-γ (IFN-γ). Treatment of cells with anti-IL-12 MAb and IL-4 to induce a Tc1-to-Tc2 shift resulted in no change in viral production levels or IFN-γ production within the HIV-1-infected CD8(+) T cell population. Initiation of a Tc2-to-Tc1 shift resulted in a 6-fold increase in HIV-1 replication and 2- to 3-fold higher levels of IFN-γ, demonstrating that infection can protect against a Tc1-to-Tc2 shift in CD8(+) T cells.  相似文献   
47.
Background/aim The aim of this study was to assess the reliability and validity of Turkish version of the Xerostomia Inventory XI in patients with primary Sjögren’s syndrome (pSS).Materials and methods A cross-sectional survey study design and analysis were used to assess the reliability and validity of the Xerostomia Inventory XI. A total of 69 patients with pSS (5 males, 64 females; mean age = 54.81 ± 8.77 years) were included. The Xerostomia Inventory XI (TR) was applied twice at an interval of 15 days. The test-retest reliability was assessed with the intraclass correlation coefficient (ICC), and the internal consistency of multiitem subscales by calculating Cronbach’s alpha values. The correlations between ESSPRI, basal and stimulated salivary flow (BSF-SSF), Oral Health Impact Profile-14 (OHIP-14) and Oral Health-Related Quality of Life-UK (OHRQoL-UK) Questionnaire were evaluated to determine the construct validity.Results The ICC value for test/retest reliability of the Xerostomia Inventory XI (TR) was 0.993. The internal consistency was 0.869. There were low to high correlations between Xerostomia Inventory XI (TR) and ESSPRI, BSF, SSF, OHIR-14 total and OHRQoL-UK total.Conclusion The Turkish version of the Xerostomia Inventory XI was found to be clinically valid and reliable to be used in clinical evaluations and rehabilitation interventions in patients with pSS.  相似文献   
48.
The authors describe a technique for performing a safe and controlled continuous curvilinear capsulorhexis (CCC) in white cataracts using the contrast-enhancing effect of green light from an endoillumination probe. After attaching a green filter to the endoillumination unit of the vitrectomy set, a CCC was performed under the green light of the endoillumination probe, which was placed on the periphery of the cornea in a manner that followed the tearing edge of the capsulorhexis. This technique may be an alternative to capsular dyes in performing a safe and controlled CCC in white cataracts.  相似文献   
49.
Congenital arteriovenous fistula (CAVF) is a rare cardiac lesion. Angina pectoris is uncommon in younger patients with CAVF. Fistula-related symptoms, complications of this anomaly and surgical complications have a strong correlation with the age of the patient. A ten-year-old male patient with angina pectoris in whom the diagnosis of CAVF was established, and who, following surgical ligation recovered, is presented.  相似文献   
50.
Saddle nose reconstruction is based on the use of support grafts to manage aesthetic and functional problems. Bone (calvarial, iliac crest, costal, nasal hump, ulnar, and heterogeneous origin), cartilage (septal, costal, heterogeneous), and synthetic materials (silicon, silastic, polyethylene) were used as support grafts. Three patients have been included in this study to define the surgical management and long-term aesthetic and functional results of patients undergoing rhinoplasty with support grafts for a saddle nose deformity. Open rhinoplasty was employed. Both the lower turbinates were excised and the bone dissected from the soft tissues in two cases and in one case, only mucosa was removed. The amount of support needed was measured by using bone wax. The bone was used shaped in layers, according to the defect, and sutured to each other by vycril suture, and wrapped around by surgicell. The graft was then inserted in its place and fixed with external prolene sutures. Results were satisfactory in both function and aesthetics. Ten to 16-month follow-ups had no complications. Saddle nose surgery basically requires the use of a support graft to repair the nasal dorsum. A lower turbinate bone graft procedure has some advantages: it is cheap and safe, it is ready to use and not time-consuming, there is no donor area and no additional donor site morbidity, and it enlarges the airway and the passage to prevent nasal airway obstruction.  相似文献   
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