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71.
Diagnosis of gastrointestinal stromal tumors: A consensus approach   总被引:258,自引:0,他引:258  
As a result of major recent advances in understanding the biology of gastrointestinal stromal tumors (GISTs), specifically recognition of the central role of activating KIT mutations and associated KIT protein expression in these lesions, and the development of novel and effective therapy for GISTs using the receptor tyrosine kinase inhibitor STI-571, these tumors have become the focus of considerable attention by pathologists, clinicians, and patients. Stromal/mesenchymal tumors of the gastrointestinal tract have long been a source of confusion and controversy with regard to classification, line(s) of differentiation, and prognostication. Characterization of the KIT pathway and its phenotypic implications has helped to resolve some but not all of these issues. Given the now critical role of accurate and reproducible pathologic diagnosis in ensuring appropriate treatment for patients with GIST, the National Institutes of Health convened a GIST workshop in April 2001 with the goal of developing a consensus approach to diagnosis and morphologic prognostication. Key elements of the consensus, as described herein, are the defining role of KIT immunopositivity in diagnosis and a proposed scheme for estimating metastatic risk in these lesions, based on tumor size and mitotic count, recognizing that it is probably unwise to use the definitive term "benign" for any GIST, at least at the present time.  相似文献   
72.
Background  Clinical diagnosis of acute bacterial sinusitis (ABS) is a concern when a patient presents with nasal discharge of recent onset together with facial pain or pressure. Given this presentation, the doctor would benefit from having access to software that specifies, first, what diagnostic indicators experts typically use in that diagnosis and then, upon entry of those facts, what experts' typical probability of ABS is in such a case.
Methods  We specified a set of 23 hypothetical presentations of this type by patients 20–75 years of age, involving a comprehensive set of clinical-diagnostic indicators. Members of an international expert panel independently set the probability of ABS in each of these cases. A logistic function of the diagnostic indicators was fitted to the medians of the probabilities.
Results  The fitting led to an expression of the experts' median probability of ABS as a joint function of the duration of the patient's facial pain/pressure, and indicators of the location(s) of this; indicators of exacerbation of the pain/pressure on bending forward, nasal obstruction, maxillary and/or frontal tenderness, pus from middle meatus, purulent postnasal drip, and fever; and indicators of recent upper respiratory tract infection, nasal polyposis and status post sinus surgery. This probability function is accessible at http://www.evimed.ch/ABS .
Interpretation  That probability function, made readily accessible, provides for expertly probability setting in clinical diagnosis of ABS, relevant for decisions about further diagnostics or treatment without further tests.  相似文献   
73.
A patient who had endometritis confirmed by endometrial biopsy and acute salpingitis confirmed by laparoscopy is reported. Chlamydia trachomatis and herpes simplex virus type two were isolated from the endometrial cavity and the fallopian tube. The histopathologic findings of the endometritis were similar to those frequently seen in chronic chlamydial eye disease or chlamydial cervicitis.  相似文献   
74.
Prevalence and manifestations of endometritis among women with cervicitis   总被引:7,自引:0,他引:7  
Thirty-five women referred from a clinic treating sexually transmitted diseases, because of suspected cervicitis, were studied for the presence of endometritis by transcervical endometrial biopsies and cervical and endometrial cultures. Fourteen (40%) of the patients had histologic evidence of endometritis. Findings that significantly correlated with endometritis included a history of intermenstrual vaginal bleeding, the presence of Chlamydia trachomatis, Neisseria gonorrhoeae, or Streptococcus agalactiae in the cervix, and the presence of serum antibodies to C. trachomatis or to Mycoplasma hominis.  相似文献   
75.
Undesired bone loss around implants is considered to occur mainly because of a stress-shielding phenomenon. Bone surrounding the total knee arthroplasty (TKA) adjusts its mineral density and structure to meet new mechanical demands. Immobilization, in combination with local operative trauma to the bone and soft tissues, has an additional impact on bone loss. The clinical survival of TKA is associated with the quality and quantity of the surrounding bone environment. Poor bone quality and quantity may predispose to aseptic implant loosening and periprosthetic fractures. We investigated the efficacy of oral bisphosphonate (alendronate, Fosamax) with calcium (Calcichew) for the inhibition of early bone mineral density (BMD) loss after TKA in a prospective, randomized, one-year follow-up study. Periprosthetic BMD changes were measured with fan-beam dual-energy X-ray absorptiometry (DXA) in 19 patients with knee osteoarthrosis. Patients (n = 8) treated with 10 mg alendronate and 500 mg calcium daily maintained distal femoral BMD values close to the baseline values (P > 0.04), while patients receiving only 500 mg of calcium daily (n = 11) showed significant bone loss during the one-year follow-up (P < 0.015). The treatment groups differed significantly in metaphyseal anterior, posterior, diaphyseal, and metaphyseal total regions of interest (ROIs) (repeated measures ANOVA analyses, P = 0.019, P = 0.010, P = 0.022, and P = 0.024, respectively). Our results indicate that oral alendronate reduces early postoperative periprosthetic bone loss significantly. This therapeutic strategy may improve the results and longevity of primary total knee arthroplasties.  相似文献   
76.
Both fragile X mental retardation protein (FMRP) and brain-derived neurotrophic factor (BDNF) are implicated in the maturation of neurons and in the higher cognitive functions. We have investigated whether FMRP and BDNF are reciprocally regulated in neurons. Exposure of cultured hippocampal neurons to BDNF, but not to NT-3, reduced FMR1 mRNA levels to 84.8% of control at 4 h and the levels were back to baseline by 24 h or 4 days. Furthermore, expression of FMR1 mRNA was reduced (82.4% of control) in vivo in the hippocampus of transgenic mice overexpressing TrkB receptors, and a small but significant (5.1%) decrease was also detected in FMRP protein levels. In contrast, the expression patterns of BDNF and TrkB mRNAs were not altered in FMRP-deficient mice compared to wild-type mice. Our data provide evidence that BDNF via TrkB signaling decreases FMRP expression and suggest a role for FMRP in BDNF-induced synaptic plasticity.  相似文献   
77.
Screening for lung cancer   总被引:3,自引:0,他引:3  
Screening for lung cancer serves to prevent deaths from this disease insofar as earlier resections are associated with higher rates of cure. There is good reason to believe that this is the case: in stage I, the 5-year survival rate with resection is 70%, whereas without resection the corresponding rate is only 10%. Before this evidence emerged, various authoritative organizations and agencies in North America advised against screening for lung cancer on the grounds of the results of several RCTs. As for CXR, I argue that the study results are consistent with up to 40% reduction in the fatality rate. Moreover, modern helical CT screening provides for detecting much smaller tumors than were detected in those studies. It is time to revoke the conclusion that screening for lung cancer does not serve to prevent deaths from this disease, and to quantify the usefulness of CT screening in particular. As for the requisite research, the prevailing orthodoxy has it that RCTs are to be used, but I argue that more meaningful results are obtainable, more rapidly and much less expensively, by the use of noncomparative (and hence unrandomized) studies.  相似文献   
78.
79.
The amygdalo-piriform transition area is a poorly defined region in the temporal lobe that is heavily connected with the olfactory system. As part of an ongoing project aimed at understanding the neuronal pathways that provide sensory information to the amygdala, we investigated the cytoarchitectonic and chemoarchitectonic features of the amygdalo-piriform transition area and its connections to the amygdaloid complex in 13 rats by using the anterograde tracer, Phaseolus vulgaris-leucoagglutinin. Our analysis indicates that the amygdalo-piriform transition area has medial (rostral and caudal portions) and lateral parts. The rostromedial part projects heavily to the intermediate and lateral divisions of the central nucleus, whereas the caudomedial part projects mainly to the medial division. The lateral part of the amygdalo-piriform transition area projects heavily to the capsular and lateral divisions of the central nucleus. Electron microscopic analysis revealed that the projection to the lateral division of the central nucleus forms asymmetric contacts with the spines and shafts of postsynaptic neurons and, therefore, is assumed to be excitatory. The amygdalo-piriform transition area also projects moderately to other amygdaloid nuclei, including the parvicellular division of the basal nucleus, the anterior cortical nucleus, and the nucleus of the lateral olfactory tract. The lateral and medial parts of the amygdalo-piriform transition area also project to the distal temporal CA1 and distal temporal subiculum, respectively. Unlike the adjacent entorhinal cortex, the amygdalo-piriform transition area does not project to the dentate gyrus. These data suggest that the amygdalo-piriform transition area is a region that influences both emotional and memory processing in parallel by means of pathways to the amygdala and the hippocampus, respectively.  相似文献   
80.
Weaver  DA; Hei  TK; Hukku  B; McRaven  JA; Willey  JC 《Carcinogenesis》1997,18(6):1251-1257
To establish a cell culture model for lung carcinogenesis, independent populations of the human papillomavirus 18-immortalized human bronchial epithelial cell line BEP2D were treated with high linear energy transfer radon-simulated alpha-particles, expanded and xenotransplanted into Nu/Nu mice. Six independent cell lines were established from tumors that developed from three separate radiation treatments as follows: treatment (Tx) 1 (30 cGy--two doses), H2BT, Tx 2 (30 cGy-- single dose), R30T1L, R30T2 and R30T3L, Tx 3 (30 cGy--single dose), H1ATN and H1ATBA1. Cytogenetic analysis revealed common changes in all tumor lines: loss of the Y chromosome (ch), one of three copies of ch8, one of three copies of ch14, and one of two copies of ch4p16-pter and ch11p15-pter. Analysis of polymerase chain reaction-amplified short tandem repeats of informative loci confirmed the loss of chY in all lines and loss of heterozygosity (LOH) at eight loci spanning the length of ch8 in all lines from Tx's 1 and 2. Our data support previous studies indicating the presence of tumor suppressor genes on ch8. LOH also was confirmed on ch14 at locus D14S306 in all cell lines from Tx 2 and in one of two lines from Tx 3. This region, 14q12-q13, may contain changes in one of the five known somatostatin receptor genes (SSTR1). No LOH was detected at any of the informative loci tested for on ch4 or ch11.   相似文献   
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