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101.
Wroblewski BM Siney PD Fleming PA Bobak P 《The Journal of bone and joint surgery. British volume》2000,82(6):842-845
The calcar femorale is a vertical plate of bone lying deep to the lesser trochanter and is formed as a result of traction of the iliopsoas which separates the femoral cortex into two distinct layers, the calcar femorale and the medial femoral cortex. They fuse together proximally to form the medial femoral neck. A stem placed centrally will abut against the calcar femorale with little or no space for cement. Clearing of the calcar will offer space for a cement layer, which will support the stem proximally on the posterior aspect. We compared two consecutive groups of Charnley low-friction arthroplasties, with and without clearing of the calcar. In 330 patients who had an arthroplasty without clearing the calcar, there were ten revisions for aseptic loosening of the stem and six other stems were considered 'definitely loose', giving a rate of failure of 4.8%. In 111 patients in whom the calcar was cleared there was only one revision for aseptic loosening and no stems were classed as 'definitely loose', giving a rate of failure of 0.9%. Survivorship analysis has again shown the need for long-term follow-up; the differences became clear after ten years but because of the relatively small numbers, statistical analysis is not yet applicable. We now clear the calcar femorale routinely and advocate optimal access to the medullary canal and insertion of the stem in the area of the piriform fossa. 相似文献
102.
Declining incidence of episodes of asthma: a study of trends in new episodes presenting to general practitioners in the period 1989-98 总被引:4,自引:2,他引:2 下载免费PDF全文
BACKGROUND: A study was undertaken to determine trends in the incidence of new episodes of asthma presented to general practitioners participating in the Weekly Returns Service of the Royal College of General Practitioners, comprising 92 practices with a registered population of approximately 680 000 persons well distributed throughout England and Wales. These practices monitor the morbidity presented at every consultation, distinguishing between new episodes of illness and ongoing consultations. METHODS: Age specific weekly rates of new episodes of asthma (and of acute bronchitis) presenting to the general practitioners over the years 1989-98 were examined in four week blocks and analysed by multiple regression, separating secular from seasonal trends. RESULTS: Quadratic trends in episodes of asthma were evident in each of the age groups with peaks in 1993/4. Corresponding analyses for acute bronchitis disclosed similar trends generally peaking in the winter of 1993/4. Mean weekly incidence data (all ages combined) decreased in all quarters since 1993. Regional analysis (North/Central/South) showed similar decreases. CONCLUSIONS: There has been a gradual decrease in the incidence of asthma episodes and of acute bronchitis presenting to general practitioners since 1993. The trend of an increase before 1993 followed by a decrease cannot be explained by changes in the patterns of health care usage or diagnostic preference of doctors. 相似文献
103.
The diagnosis of vascular cell tumors of the upper limb in children can be extremely difficult. There is considerable variation in their presentation and natural history. In most instances, the correct diagnosis can be achieved after a careful history and examination. Almost invariably, they are benign lesions and, of these, hemangiomas and vascular malformations account for more than 90%. Worrying tumors of the intermediate and malignant grade are rare. Any atypical, rapidly growing tumor with superficial ulceration and bony destruction on radiology should be regarded as malignant. Histologic differentiation of all problematic vascular swellings requires the services of an experienced pediatric vascular pathologist. In the future, specific cellular marker profiles of individual lesions may simplify the diagnosis. Conservative, symptomatic management is the first line of treatment for almost every vascular swelling. Intervention is reserved for swellings complicated by ulceration, uncontrollable rapid growth, coagulopathies, cardiovascular compromise, or the possibility of malignancy. Small lesions may generally be simply excised, whereas larger lesions often remain a problem. 相似文献
104.
Identification and validation of genes involved in the pathogenesis of colorectal cancer using cDNA microarrays and RNA interference. 总被引:47,自引:0,他引:47
Noelle Sevilir Williams Richard B Gaynor Shane Scoggin Udit Verma Tunc Gokaslan Clifford Simmang Jason Fleming Denise Tavana Eugene Frenkel Carlos Becerra 《Clinical cancer research》2003,9(3):931-946
PURPOSE: The purpose of this study was to profile gene expression changes in colorectal tumors to identify new targets and strategies for the management of this disease. EXPERIMENTAL DESIGN: cDNA microarray analysis was used to detect differences in gene expression between normal tissue and colon tumors and polyps isolated from 20 patients. To identify genes that are important in regulating the growth properties of colorectal cancer, RNA interference (RNAi) was used to disrupt expression of several of the overexpressed genes in a colon tumor cell line, HCT116, which showed similar patterns of gene expression as many of the patient tumors. RESULTS: Expression changes of > or =2-fold in approximately one-third of the patients were consistently observed for 2632 of a total of 9592 genes (574 up-regulated genes and 2058 down-regulated genes). Subsequent analysis of 13 genes by quantitative real-time PCR confirmed the reliability of this analysis. RNAi-mediated disruption of the expression of one of these genes, survivin, a potent inhibitor of apoptosis, severely reduced tumor growth both in vitro and in an in vivo xenograft model. CONCLUSIONS: The combined use of microarray analysis and RNAi provides an excellent system to define the role of specific genes that are up-regulated in cancer lead to the increased in vitro and in vivo growth of colon tumors. 相似文献
105.
Abstract: Haemoptysis in otherwise healthy children is an uncommon event. Two cases of massive haemoptysis, subsequently requiring lobectomy, are discussed. In each case, foreign vegetable matter was identified despite previously normal bronchoscopy and minimal changes on chest radiograph. 相似文献
106.
Non-invasive detection of fecal protein kinase C betaII and zeta messenger RNA: putative biomarkers for colon cancer 总被引:2,自引:0,他引:2
Davidson LA; Aymond CM; Jiang YH; Turner ND; Lupton JR; Chapkin RS 《Carcinogenesis》1998,19(2):253-257
We have developed a non-invasive method utilizing feces, containing
sloughed colonocytes, as a sensitive technique for detecting diagnostic
colonic biomarkers. In this study, we used the rat colon carcinogenesis
model to determine if changes in fecal protein kinase C (PKC) expression
have predictive value in monitoring the neoplastic process. Weanling rats
were injected with saline or azoxymethane (AOM) and 36 weeks later fecal
samples and mucosa were collected, poly A+ RNA isolated, and quantitative
RT-PCR performed using primers to PKC betaII and zeta. Fecal PKC betaII and
zeta mRNA levels were altered by the presence of a tumor, with
tumor-bearing animals having a 3-fold higher (P < 0.05) PKC betaII
expression as compared with animals without tumors. In addition,
AOM-injection increased mucosal PKC betaII mRNA expression compared with
saline controls. No effect of tumor incidence on mucosal PKC betaII
expression was observed. In contrast, fecal PKC zeta expression was
2.5-fold lower (P < 0.05) in animals injected with azoxymethane versus
saline. Since tumor incidence exerts a reciprocal effect on fecal PKC
betaII and zeta mRNA expression, data were also expressed as the ratio
between PKC betaII and zeta. The isozyme ratio was strongly related to
tumor incidence, i.e. ratio for animals with tumors was 2.18 +/- 1.25,
animals without tumors was 0.50 +/- 0.16, P = 0.025. We demonstrate that
the expression of fecal PKC betaII and zeta may serve as a noninvasive
marker for development of colon tumors. A sensitive technique for the
detection of colon cancer is of importance since early diagnosis can
substantially reduce mortality.
相似文献
107.
108.
Cytoreductive surgery with intraperitoneal hyperthermic chemotherapy for disseminated peritoneal cancer of gastrointestinal origin 总被引:11,自引:0,他引:11
No standard effective treatment exists for peritoneal carcinomatosis of gastrointestinal origin. The pharmacokinetic advantage of intraperitoneal chemotherapy and the synergy of heat and certain anticancer agents have prompted researchers to investigate intraperitoneal hyperthermic chemotherapy in treating disseminated peritoneal cancers. We have conducted a large Phase II trial to determine the safety and efficacy of aggressive cytoreductive surgery and intraperitoneal hyperthermic chemotherapy (IPHC) in treating peritoneal carcinomatosis of gastrointestinal origin. Patients with disseminated peritoneal carcinomatosis of gastrointestinal origin with or without malignant ascites were eligible. After aggressive surgical debulking, patients were administered a 2-hour heated (40.5 degrees C) intraperitoneal perfusion with mitomycin C. The major response variable monitored was overall survival. Patients were assessed for toxicity after IPHC administration using the National Cancer Institute Common Toxicity Criteria. Eighty-four patients with peritoneal carcinomatosis of gastrointestinal origin were evaluated for survival and toxicity (colon, n = 38; appendix, n = 22; stomach, n = 19; other gastrointestinal, n = 5). Thirty-nine (46%) patients had malignant ascites at the time of therapy. The operative mortality (30-day) was 6 per cent. Hematologic toxicity was the most common toxicity but was of mild to moderate severity (7 and 4% of patients had grade 3/4 white blood cell or platelet toxicity, respectively). The overall median survival was 14.3 months. The median survival of patients with peritoneal carcinomatosis of appendiceal, colorectal, and gastric origins were 31.1+, 14.6, and 10.1 months, respectively. Significant differences in median survival were seen in patients without and with malignant ascites (27.7 vs 7.6 months; P = 0.0004) and R0/R1 (complete gross tumor resection) versus R2 (gross residual tumor) surgical resection status (28.5+ vs 10.8 months, P = 0.0002). These data suggest that aggressive cytoreductive surgery with IPHC using mitomycin C is safe and effective in treating peritoneal carcinomatosis of gastrointestinal origin. Additional studies and broader applications of this treatment are encouraged. 相似文献
109.
Michael J Barsoom Amy McEntaffer Alfred Fleming Henry C Nipper 《The journal of maternal-fetal & neonatal medicine》2006,19(7):443-444
Severe preeclampsia rarely occurs prior to 20 weeks of gestation except in pregnancies with triploidy. The patient reported herein is a 29-year-old primigravida who developed severe preeclampsia at 20 weeks of gestation. Evaluation of the pregnancy demonstrated a markedly abnormal quadruple screen. Amniocentesis demonstrated a fetus with triploidy, despite a normal appearance. 相似文献
110.
Louise Burke Douglas B Flieder Donald G Guinee Elizabeth Brambilla Andrew N Freedman William P Bennett Raymond T Jones Andrew Borkowski Neil A Caporaso Marian Fleming Victor Trastek Peter Pairolero Henry Tazelaar David Midthun James R Jett Lance A Liotta William D Travis Curtis C Harris 《Clinical cancer research》2005,11(1):232-241
PURPOSE: Many studies have highlighted the aberrant expression and prognostic significance of individual proteins in either the Rb (particularly cyclin D1, p16INK4A, and pRb) or the p53 (p53 and p21Waf1) pathways in non-small cell lung cancer. We hypothesize that cumulative abnormalities within each and between these pathways would have significant prognostic potential regarding survival. EXPERIMENTAL DESIGN: Our study population consisted of 106 consecutive surgically resected cases of predominantly early-stage non-small cell lung cancer from the National Cancer Institute-Mayo Clinic series, and assessment of proteins involved both immunohistochemical (cyclin D1, p21Waf1, pRb, p16INK4A, and p53) and mutational analysis (p53) in relationship to staging and survival. RESULTS: Cyclin D1 overexpression was noted in 48% of the tumors, p16INK4A negative in 53%, pRb negative in 17%, p53 immunopositive in 50%, p53 mutation frequency in 48%, and p21(Waf1) overexpression in 47%, none with prognostic significance. Cyclin D1 overexpression in pRb-negative tumors revealed a significantly worse prognosis with a mean survival of 2.3 years (P = 0.004). A simultaneous p53 mutation dramatically reduced the mean survival time to 0.9 years (P = 0.007). Cyclin D1 overexpression with either a p53 mutation or a p53 overexpression was also associated with a significantly poorer prognosis (P = 0.0033 and 0.0063, respectively). CONCLUSIONS: Some cumulative abnormalities in the Rb and p53 pathways (e.g., cyclin D1 overexpression and p53 mutations) significantly cooperate to predict a poor prognosis; however, the complexity of the cell cycle protein interaction in any given tumor warrants caution in interpreting survival results when specific protein abnormalities are taken in isolation. 相似文献