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31.
32.
Pulivarthi H Rao Charles P Harris Xin Yan Lu Xiao-Nan Li Samuel C Mok Ching C Lau 《Genes, chromosomes & cancer》2002,33(2):123-132
We applied multicolor spectral karyotyping (SKY) to decipher the chromosomal complexity of a panel of seven cell lines and four primary tumors derived from patients with high‐grade serous adenocarcinoma of the ovary. By this method we identified a total of 188 unbalanced translocations, nine reciprocal translocations [t(2;15)(q13;q23), t(7;17) (q32;q21), t(8;22)(p11;q11), t(8;22) (q24;q13), t(10;19) (q24;q13.2), t(11;19) (q13;p11), t(12;21)(q13;q22),t(18;20) (q?11;q?11), t(18;22)(q?11;q?13)], 6 isochromosomes [i(1q), i(7q), i(8q), i(9p), i(17q), i(21q)], and 23 deletions. By detailed mapping of rearrangement breakpoints, it was possible to identify several recurring breakpoint clusters at chromosomal bands 1p36, 2p11, 2p23, 3p21, 3q21, 4p11, 6q11, 8p11, 9q34, 10p11, 11p11, 11q13, 12p13, 12q13, 17q21, 18p11, 18q11, 20q11, and 21q22. Recurrent interstitial deletion of chromosomal bands 8p11, 11p11, and 12q13 and a recurrent unbalanced translocation—der(6)t(6;8)(q11;q11)—were also identified. In addition, a homogeneously staining region localized in one cell line to 11q13 was found using SKY to be derived from genetic material originating from chromosome 12. Subsequent comparative genomic hybridization (CGH) studies on this tumor revealed the amplification of DNA sequences derived from the short arm of chromosome 12 at the 12p11.2 region. These studies demonstrate the power of SKY, CGH, and G‐banding to resolve the full spectrum of chromosomal rearrangements in serous ovarian adenocarcinoma. © 2002 Wiley‐Liss, Inc. 相似文献
33.
Kim SH Shin JW Park SA Kim YK Park MS Mok JM Yang WI Lee JW 《Journal of biomedical materials research. Part B, Applied biomaterials》2004,68(1):69-74
The purpose of this study is to determine the efficacy of bioactive calcium phosphate obtained from porcine cancellous bone for the treatment of bone defects and nonunion. Porcine cancellous bone blocks were heat treated at 1300 degrees C for 2 h. The chemical composition, calcium-to-phosphate ratio, and microstructure of the porcine bone blocks were examined. For in vivo implantation, bone defects were created on the anteromedial aspect of the proximal tibia in seven beagle dogs and the xenograft bone blocks were placed into these defects. Plain radiographs were taken at 2-week intervals for roentgenographic evaluation. At 12 weeks, the specimens were stained with hematoxylin and eosin (H&E). The composition and morphology of heat-treated porcine cancellous bone were found to be similar to heat-treated human cancellous bone. Radiographs showed union between the host bone/bone-block interfaces. At 12 weeks, uniform and substantial new bone formation was observed. It is concluded that heat-treated porcine cancellous bone demonstrated effective osteoconductivity. This high-temperature heat-treatment technique has several advantages, including decreased risk of disease transmission and immunoreactivity, while also offering excellent biocompatibility. 相似文献
34.
Ultrastructure of preimplantation human embryos co-cultured with human ampullary cells 总被引:2,自引:2,他引:2
H Sathananthan A Bongso S C Ng J Ho H Mok S Ratnam 《Human reproduction (Oxford, England)》1990,5(3):309-318
Ova with two pronuclei were co-cultured with established human ampullary cell lines and various stages of preimplantation embryonic development were monitored by Nomarski optics and then assessed by transmission electron microscopy (TEM). Fifteen embryos ranging from the 2-cell stage to blastocyst hatching were examined for normal and abnormal features. Their ultrastructure was similar to that of embryos cultured in Whittingham's T6 medium, reported previously. Seven embryos were evidently morphologically normal and showed good organization of fine structure. Most cellular organelles underwent progressive changes during early development. There was evidence of enhanced embryonic genome activation at the 8-cell stage. Invariably, all embryos had few too many fragments, some internalized, which were later segregated into the blastocoele or found outside the trophoblast of the late morula and blastocysts. Six grossly 'normal' embryos assessed by Nomarski had multiple nuclei of various dimensions, which highlights the subjectivity of embryo assessment in the IVF laboratory. Incomplete incorporation of chromatin into nuclei and formation of micronuclei were evident in some blastomeres. The results are discussed in relation to early embryonic loss, prevalent in IVF. Significant events reported include the detection of centrioles at the 8-cell stage, cavitation of the early blastocyst and the initiation of blastocyst hatching visualized by TEM. 相似文献
35.
Mina Ben-bassat Diana Braslavsky Danny Lotan Bella Eisenstein Miriam Davidovitz Harry Stark 《Ultrastructural pathology》1988,12(1):1-16
In an attempt to recognize early stages of focal segmental glomerulosclerosis (FSGS) in patients with a clinical course suggesting a diagnosis other than minimal change disease (MCD) and normal histology, or minor, nondiagnostic changes on light microscopy (LM), we used a protocol for systematic and extensive electron microscopy (EM) examination of kidney biopsies obtained from such patients. By this method ultrastructural pathology was found in 8 patients. These changes were localized, involving only portions of single glomerular segments. The findings included mild to moderate increase of the mesangial matrix, focal wrinkling of the capillary basement membrane, and early obliteration of the normal architecture of individual capillary loops, as well as electron-dense deposits in a mesangial and subendothelial distribution. Of these 8 patients, 2 are at present in remission without therapy (in 1, following therapy with cyclophosphamide); 3 are in remission on steroid therapy; 1 developed massive proteinuria during pregnancy, after a spontaneous remission lasting almost 2 years; 1 patient advanced to terminal renal failure 3 1/2 years after biopsy; and 1 died of sepsis 1 month after biopsy. We believe that the ultrastructural changes found may represent early or mild FSGS and that the protocol described can add valuable information in clinically worrisome patients in whom renal histology appears normal. 相似文献
36.
Michael W. O'Hara Claudia J. French Ellen M. Zekoski Danny J. Neunaber Gary W. Schroeder 《Cognitive therapy and research》1985,9(3):267-275
According to the reformulated learned helplessness model of depression, causal attributions are an important mediator of the effects on mood of positive and negative experiences. Adaptive attributions for negative events are assumed to be external, unstable, and specific. In the present study, subjects exposed to one of two attribution training procedures or a control condition made attributions for hypothetical events under neutral and adaptive instructional sets. Attributions were rated by subjects and coders blind to the purpose of the study. Results indicated that subjects' views of adaptive causal attributions were congruent with predictions from the learned helplessness model. The ratings of the objective coders indicated that subjects' attributions really did change in response to the adaptive instructions in the predicted direction. Implications of these results for the reformulated learned helplessness model and depression therapies that include an attribution retraining component are discussed.The authors would like to thank Dan Russell for his very helpful comments on earlier drafts of this paper. 相似文献
37.
Mok N 《Proceedings of the National Academy of Sciences of the United States of America》1986,83(8):2288-2290
Let X = Ω/Γ be a compact quotient of an irreducible bounded symmetric domain Ω of rank ≥2 by a discrete group ω of automorphisms without fixed points. It is well known that the Kähler-Einstein metric g on X carries seminegative curvature (in the sense of Griffiths). I show that any Hermitian metric h on X carrying seminegative curvature must be a constant multiple of g. This can be applied to prove rigidity theorems of holomorphic maps from X into Hermitian manifolds (Y, k) carrying seminegative curvature. These results are also generalized to the case of quotients of finite volume. On the other hand, let (Xc, gc) be an irreducible compact Hermitian symmetric manifold of rank ≥2. Then gc is Kähler and carries semipositive holomorphic bisectional curvature. I prove that any Kähler h on Xc carrying semipositive holomorphic bisectional curvature must be equal to gc up to a constant multiple and up to a biholomorphic transformation of Xc. 相似文献
38.
In the in vivo system, cancer metastasis is a complex multi-step process. We have utilized an in vitro three-dimensional system to study the initial stages of tumour cell invasion. In this communication, the sequence of events in interactions between B16 melanoma cells and normal mouse skin fibroblasts are described. It is proposed that tumour cells produce a "retractive factor" which induces the underlying fibroblasts to retract so as to facilitate invasion and metastasis. 相似文献
39.
Risk factors for postoperative ileus after oblique lateral interbody fusion: a multivariate analysis
Sung Cheol Park Sam Yeol Chang Sujung Mok Hyoungmin Kim Bong-Soon Chang Choon-Ki Lee 《The spine journal》2021,21(3):438-445
Background ContextOblique lateral interbody fusion (OLIF)–has become a widely used, efficient surgical tool for various degenerative lumbar conditions. Postoperative ileus (POI) is a relatively common complication after anterior lumbar interbody fusion due to the manipulation of the intestine during the surgical approach. However, to our knowledge, little is known about POI following OLIF even though it also involves bowel manipulation during a surgical procedure.PurposeTo assess the incidence of POI and identify independent risk factors for POI development after OLIF.Study Design/SettingRetrospective cohort study.Patient SampleAll consecutive patients who underwent OLIF and percutaneous pedicle screw instrumentation from August 2012 until October 2019 at a single institutionOutcome MeasuresPatient demographics (sex, age, body weight, height, and body mass index), comorbidities (diabetes mellitus, gastroesophageal reflux disease, antithrombotic medication, previous abdominal surgery, and previous lumbar surgery), and perioperative details (preoperative diagnosis, number of levels fused, inadvertent endplate fracture during cage insertion, type of interbody graft, intraoperative estimated blood loss, duration of surgery and anesthesia, the amount of intraoperative remifentanil and propofol used as anesthetic agents, the total postoperative retroperitoneal closed-suction drainage output, and the cumulative opioid dosage administered in the first 72 hours postoperatively).MethodsPOI was defined as 2 or more of the following at 72 hours postoperatively: (1) ongoing nausea or vomiting postoperatively, (2) the absence of flatus over last 24-hour period, (3) inability to tolerate an oral diet over last 24-hour period, (4) ongoing abdominal distention postoperatively, and (5) radiological confirmation. The subjects were divided into 2 groups: patients with POI and those without POI. Binary logistic regression analyses were performed on demographics, comorbidities, and perioperative factors to identify independent risk factors for POI.ResultsEighteen (3.9%) of 460 patients experienced POI after OLIF and percutaneous pedicle screw instrumentation. Patients with POI had a significantly longer postoperative length of hospital stay than those without POI (8.61 ± 2.66 vs 6.48 ± 2.64, p = .001). Multivariate logistic regression analysis identified inadvertent endplate fracture (adjusted odds ratio = 6.017, p = .001) and the amount of intraoperative remifentanil (adjusted odds ratio = 1.057, p = .024) as independent risk factors for the occurrence of POI following OLIF.ConclusionThis study identified inadvertent endplate fracture and the amount of intraoperative remifentanil as independent risk factors for the development of POI after OLIF. 相似文献
40.
The skeleton as a unique environment for breast cancer cells 总被引:5,自引:0,他引:5
Bone is a favored location for several cancer metastases especially breast, prostate and myeloma. This review evaluates various
properties of the skeleton that contribute to its successful colonization by breast cancer cells. The first consideration
is the unique aspects of the vasculature of metaphyseal bone, which may account for the initial lodging of breast cancer cells
in specific regions of the skeleton. Metasphyseal bone, found at the ends of long bone, in ribs and in vertebrae, is comprised
of trabecular bone interspersed with marrow and a rich vasculature. The chemotactic factors that arise from bone marrow and
bone cells are discussed in terms of cancer cell migration out of the vasculature and entry of cancer cells into the marrow
cavity. Once the breast cancer cells have migrated into the metaphysis, they interact both directly and indirectly with bone
cells and other cells in the marrow. As tumor growth progresses, functional bone cells are lost, most likely through apoptosis.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献