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841.
Frazier Patricia; Keenan Nora; Anders Samantha; Perera Sulani; Shallcross Sandra; Hintz Samuel 《Canadian Metallurgical Quarterly》2011,100(4):749
[Correction Notice: An erratum for this article was reported in Vol 100(4) of Journal of Personality and Social Psychology (see record 2011-05716-005). There is an error on page 758. In the sentence “Present control predicted later event-specific distress in Sample 1( β = .17, p 相似文献
842.
TS Emory BW Scheithauer T Hirose M Wood BM Onofrio RB Jenkins 《Canadian Metallurgical Quarterly》1995,103(6):696-704
The nature of perineurioma, variably termed "localized hypertrophic neuropathy," "intraneural neurofibroma," and "hypertrophic interstitial neuritis" has long been an issue of contention. Most authors consider it a neoplasm, but some a reactive process. Eight clinically and morphologically typical perineuriomas were studied by histologic, immunohistochemical and ultrastructural methods. One perineurioma was subject to tissue culture and cytogenetic study and another to fluorescence in situ hybridization (FISH) analysis. The patients, 3 males and 5 females, ranged in age from 11 to 38 years. All tumors were intraneural, and involved extremities (2 sciatic, 1 median, 1 femoral, 1 peroneal, 1 brachial plexus, 1 ulnar, and 1 radial). Neurologic symptoms, motor in all cases and sensory in 4, were present from 1 month to 7 years (mean 1.2 years). Fusiform, segmental nerve enlargement was clinically apparent in only two patients, but was evident on MRI in five of eight patients. Lesion length ranged from 3.5 to 30 cm, the largest involving the sciatic nerve from the obturator foramen to the knee. One lesion involved two nerve roots, but no association with a phakomatosis was noted. Treatment consisted of biopsy in six cases and resection in two cases. Histologically, pseudo-onion bulbs composed of epithelial membrane antigen-reactive, S-100 protein-negative perineurial cells surrounded myelinated or nonmyelinated nerve fibers. Many were accompanied by their S-100 protein-positive Schwann sheaths. Some whorls lacked a central axon. A single mitosis was noted in one case. The MIB-1 antigen labelling index ranged from 4% to 17%. Staining for p53 antigen in six cases showed no (2 of 6), rare (2 of 6), or scattered (2 of 6) immunoreactive nuclei. Cytogenetic analysis in one case demonstrated a chromosomally abnormal clone. Each of 16 metaphases was abnormal; the tumor cells appeared to be homozygously deficient for the region 22q11.2qter. In another case, 53% of interphase nuclei showed three FISH signals with a chromosome 14/22 probe, thus suggesting either monosomy for the centromere of chromosome 14 or that of chromosome 22.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
843.
The purpose of this study was to document whether the technical qualities of a brachytherapy application impacts on the outcome of patients with locally advanced cervix cancer treated by definitive irradiation. A previous report from the patterns of care study demonstrated the importance of brachytherapy in the treatment of locally advanced cervix cancer. Locally advanced disease was defined as FIGO stages Ib (if tumor diameter was < or = 4 cm), IIb (if disease was bilateral or involved the lateral aspect of either parametrium), and III. Localization films from 128 patients with locally advanced squamous cell carcinoma of the cervix were reviewed by a radiation physicist and a radiation oncologist with expertise in gynecologic radiotherapy. All patients received external beam irradiation followed by one brachytherapy application (median point A dose = 8040 cGy; range, 4083-10,020 cGy). Brachytherapy parameters assessed were (a) the distance between the right colpostat source and the distal tandem source, (b) the distance between the left colpostat source and the distal tandem source, and (c) the symmetry of colpostat placement. Implants were scored as "ideal" (n = 8) when all three parameters were deemed satisfactory, "unacceptable" (n = 17) when none of the parameters was deemed satisfactory, and "adequate" (n = 41) in all other cases. Significantly improved 5-year local control was seen when comparing ideal and adequate placements to unacceptable placements (68% vs 34%, P = 0.02). A strong trend toward improved 5-year survival was also noted among the group with ideal and adequate implants as opposed to unacceptable implants (60% vs 40%). Multivariate analysis showed that the technical adequacy of the brachytherapy implant was the most important prognostic discriminant of local control. In conclusion, these analyses demonstrate the direct influence of competent technical implant performance on tumor control and even survival. While only a small fraction of implants for cervical cancer are performed poorly in the United States, there is a need for continued emphasis of the principles for proper implant technique. 相似文献
844.
BW Kong 《Canadian Metallurgical Quarterly》1997,8(4):409-415
BACKGROUND AND OBJECTIVE: Recent studies have sought to utilize diode laser "micropulsing" in order to preserve therapeutic efficacy of retinal photocoagulation while minimizing pain and subjacent tissue injury. A model for the transient thermal tissue response to continuous and micropulsed diode laser output is presented in order to understand the laser-tissue interactions and to generate optimum parameters for exploiting potential advantages of micropulsed application. STUDY DESIGN/MATERIALS AND METHODS: The tissue thermal response was calculated by convolving the analytical solution to the three-dimensional, isotropic heat conduction equation with a source term corresponding to the spot size of the laser incident on the absorbing retinal pigment epithelium (RPE) and choroid layers of the ocular fundus. Thermal localization is quantitated by comparing the temperature rise in the RPE (T(RPE) and deep choroid (T(Ch). A 1-watt (average power), 20-microns diameter, 100 ms pulse (continuous or micropulsed) of 810 nm radiation was modelled to be incident on a geometric idealization of the human retina and choroid. RESULTS: A temperature gradient is rapidly established with only modest temperature augmentation between 10 and 100 ms. At 100 ms T(RPE) and T(Ch) are 32 and 23 C, respectively, for continuous application, and 41 and 27 C for 2 ms on/off micropulsed application. For a duty factor (total laser "on" time divided by pulse length) of 50%, T(RPE)/T(Ch) is maximal for a micropulse on/off duration of 2 ms; however, the variation over micropulse durations from 200 microseconds to 50 ms is small. In addition, whereas end-pulse T(RPE)/T(Ch) is greater for 2 ms on/off application when compared with continuous delivery (1.53 vs. 1.39), thermal relaxation during pulse quiescence in the micropulsed mode allows for an early increase in deep choroidal temperature with respect to T(RPE). For ten 200 microseconds pulses equally separated over 100 ms (duty factor = 2%), T(RPE)/T(Ch) = 3.2. With more numerous, lower power micropulses, T(RPE)/T(Ch) decreases monotonically to 1.39 as the duty factor is increased to 100%. CONCLUSION: These modelling studies provide the first quantitative predictions of thermal localization achieved with diode laser micropulsing and demonstrate that short pulse lengths and low duty factors allow for maximum thermal localization. These studies will potentiate pulse-shape optimization strategies for diode laser retinal photocoagulation applications. 相似文献
845.
Observations with the light microscope and the scanning and transmission electron microscopes have shown that the anterior end of Monocotyle spiremae has 8 slit-like apertures on the ventrolateral margins at each side of the mouth. Gland cells located next to the pharynx produce rod-shaped secretory bodies that are conveyed in ducts that open on to the surfaces of rounded lobes inside "reservoirs" behind each ventral, slit-like aperture. Rod-shaped secretory bodies are extruded into the "reservoirs" and appear to combine and form a homogeneous secretion which may bond the ventrolateral regions of the head of the parasite to a substrate. At no stage, however, were intact rods observed outside the duct endings. Gland cells that produce an ovoid secretory body also supply the head of M. spiremae, but ducts from these open dorsal and anterior to the mouth in a region where the parasite is not known to attach. There appears to be little or no chance for the ventral rods and the dorsal ovoid secretion to mix. This is the first record of a monogenean parasite with a single type of secretion supplying the ventral surfaces of the anterior end. The rods in M. spiremae differ in some respects from the rod-shaped bodies recorded previously among gyrodactylid, dactylogyrid, capsalid and acanthocotylid monogeneans. 相似文献
846.
GE Glass W Livingstone JN Mills WG Hlady JB Fine W Biggler T Coke D Frazier S Atherley PE Rollin TG Ksiazek CJ Peters JE Childs 《Canadian Metallurgical Quarterly》1998,59(5):699-703
Flexor pulleys in the hindpaw digits of twenty-eight adult mixed-breed dogs were reconstructed in order to investigate the influence, on the reconstruction, of the source of the autogenous tissue (intrasynovial compared with extrasynovial tendon) and the tension applied during the repair. The ipsilateral peroneus longus tendon was used to reconstruct the A2 pulley with an around-the-bone technique in twenty-one digits; the graft was sutured at a tension of 0.49, 0.98, and 1.96 newtons in seven digits each. The flexor digitorum profundus tendon of an adjacent digit was used to reconstruct the A2 pulley, at a tension of 0.98 newton, in seven additional digits. The contralateral digits were used as controls for all twenty-eight treated digits. The digits were tested in a custom apparatus designed to measure the frictional force generated between the reconstructed pulley and the tendon beneath it. The frictional force did not differ significantly (p > 0.5) among the three groups repaired with peroneus longus tendon; however, the average value was more than five times that produced in the contralateral, control digits. The average frictional forces created by the flexor digitorum profundus grafts were similar to those in the contralateral, control digits. Reconstruction with the flexor digitorum profundus at a tension of 0.98 newton produced significantly less frictional force (p < 0.05) than that produced by the peroneus longus graft at the same tension. This in vitro model of reconstruction of the A2 pulley demonstrated that tendon from an intrasynovial source (the flexor digitorum profundus) produced less frictional resistance to gliding of the tendon than did tendon from an extrasynovial source (the peroneus longus). This result is consistent with previously published findings that intrasynovial tendons may make better grafts than extrasynovial tendons for the reconstruction of gliding flexor tendons because of decreased friction and better healing qualities. Intrasynovial tendons may also make better grafts for the reconstruction of flexor pulleys. 相似文献
847.
SH Travers JI Labarta SE Gargosky RG Rosenfeld BW Jeffers RH Eckel 《Canadian Metallurgical Quarterly》1998,83(6):1935-1939
In conditions associated with insulin resistance, insulin-like growth factor binding protein-I (IGFBP-I) levels have been shown to correlate inversely with insulin levels. Puberty is associated with insulin resistance and thus provides a model for comparing the relationship of IGFBP-I to both insulin levels and measures of insulin sensitivity. Our study population consisted of 104 healthy pubertal children, age 9.8-14.6 yr. Each subject had his/her insulin sensitivity (Si) assessed by the modified minimal model of Bergman, which employs a frequently sampled i.v. glucose tolerance test. Results showed that IGFBP-I levels were significantly higher in boys than in pubertally matched girls (P < 0.01). There was a strong positive correlation between IGFBP-I levels and Si (r = 0.65, P < 0.0001) and a weaker negative correlation with fasting insulin levels (r = -0.38, P < 0.0001). An inverse relationship was also found between IGFBP-I levels and body mass index (r = -0.46, P < 0.0001) and with IGF-I levels (girls only, r = -0.41, P < 0.003). Consequently, insulin sensitivity, obesity, and IGF-I are important predictors of IGFBP-I levels in pubertal children. It is possible that insulin-mediated suppression of IGFBP-I in obese children may increase free IGF-I levels and thus contribute to somatic growth. The same mechanism may operate in pubertal children, where insulin resistance and growth acceleration occur simultaneously. 相似文献
848.
RK Valicenti LG Gomella M Ismail SG Mulholland RO Petersen BW Corn 《Canadian Metallurgical Quarterly》1998,42(3):501-506
Glucocorticoids (GC) are potent anti-inflammatory and immunosuppressive agents that act on many cells of the body, including monocytes. Here we show that a 5-day course of high dose GC therapy differentially affected the CD14++ and the CD14+ CD16+ monocyte subpopulations in 10 patients treated for multiple sclerosis. While the classical (CD14++) monocytes exhibited a substantial increase from 495 +/- 132 to 755 +/- 337 cells/microl, the CD14+ CD16+ monocytes responded with a pronounced decrease from 36 +/- 15 to 2 +/- 3 cells/microl (P < 0.001). In 4/10 patients the CD14+ CD16+ monocytes fell below detection limits (<0.2 cells/microl). This observation was confirmed when the CD14+ CD16+ monocytes were identified by virtue of their low CD33 expression as these cells decreased as well. After discontinuation of GC therapy the CD14+ CD16+ monocytes reappeared and reached normal levels after 1 week. The profound depletion of CD14+ CD16+ monocytes by GC as described here is a novel effect of GC action in vivo and may contribute to GC-mediated immunosuppression. Determination of the number of this monocyte subset may also serve to monitor the effectiveness of GC therapy in patients requiring immunosuppressive treatment. 相似文献
849.
The photophysical characteristics of two second-generation PDT photosensitizers, tin ethyl etiopurpurin I (SnET2) and tin octaethylbenzochlorin (SnOEBC), have been measured in homogeneous solution and when bound to bovine serum albumin (BSA). The ground state and triplet state absorption spectra have been characterized, as have triplet lifetimes and quantum yields for intersystem crossing, singlet oxygen formation and photobleaching. In total, these parameters provide a complete set of data that can be used to quantitatively compare the photosensitizing efficiencies of these molecules. The photo-bleaching quantum yield of SnET2 is increased dramatically when it is bound to BSA, thus limiting the production of singlet oxygen at incident fluences above 1 J/cm2. In contrast, the quantum yield of photobleaching of SnOEBC is at least an order of magnitude lower than that of SnET2 under these conditions and does not significantly limit the photosensitization process for typical in vivo or in vitro fluences. This difference is expected to play a significant role in determining the relative photo-sensitizing ability of these compounds in vivo. 相似文献
850.
Reliability aspects of packaging and integration technology for microfluidic systems 总被引:1,自引:0,他引:1
This paper presents the reliability aspects of an integrated microfluidic-system-interface (MSI) technology for complex microfluidic systems. MSI technology provided three primary functional interface components: microfluidic interconnects, integrated microvalves, and optical windows. The microfluidic interconnects were designed to facilitate complex micro-to-macro fluid interfacing between the microsystem and the macro world in a single package. The functionality and reliability of the fluid interconnects were tested using standard capillary tubing. The pneumatic microvalves were integrated directly into the microfluidic interface. The valve leak-rate characteristics and the bonding stability between the integrated microfluidic interface and the microfluidic system were tested against the pneumatic-valve pressure. Use of the optical windows in the interface was demonstrated by enabling an on-chip infrared polymerase-chain-reaction (PCR) process. This paper demonstrates the use of MSI technology as a facile and reliable interface/packaging method for a complex microfluidic system. 相似文献