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51.
The aim of this study was to investigate the loading demands placed on the intact limb in terms of joint moments and power for active trans-femoral and trans-tibial amputees in comparison to a group of able-bodied subjects. Four (4) trans-tibial, 4 trans-femoral amputees and 10 able-bodied subjects walked at 1.2m.s(-1) along a walkway whilst kinematic data from both the intact and prosthetic limbs, and kinetic data from the intact limb only were collected. A Panasonic VHS video camera was used to film subjects walking in the sagittal plane with simultaneous force data collected from a Kistler force platform. The amputees were found to compensate for the functional loss of one or more joints by increasing net joint moments and power output on their intact limb compared to able-bodied subjects. At the intact limb ankle, the range of motion, peak dorsiflexor moment and power generation at toe-off increased. At the intact limb knee, power generation during stance and extensor moments and power absorption at toe-off increased. At the intact limb hip, extensor moment and power absorption during stance, and hip flexor moment and power generation at toe-off increased. These findings were partly attributed to the prostheses used but mainly to adaptation mechanisms displayed by trans-femoral and trans-tibial amputees. They have implications for the mobility of amputees and the long term health of their joints. It was recommended that prosthesis design, prosthesis fitting and training in the use of the prosthesis were all factors which could be investigated with a view to minimising intact limb loading.  相似文献   
52.
Predictive testing for BRCA1 and 2 mutations: a male contribution.   总被引:1,自引:0,他引:1  
BACKGROUND: Management strategies for women carrying BRCA1 and 2 mutations are becoming clearer and predictive testing for a known family mutation is commonly undertaken. Implications for men are not as clear and they participate less frequently. PATIENTS AND METHODS: Twenty-six men from 10 extended families underwent predictive testing. Their motivation, reaction and outcome were studied. Subjects had appropriate pre- and post-test counselling. Informed consent was obtained before predictive testing for known deleterious mutations. DNA analysis followed standard procedures. RESULTS: Eighteen tested positive and eight negative. Four had adverse psychological reactions and three reneged on their commitments to impart results. The spouse of another man had an adverse psychological reaction to the disclosure of his positive result. Two, already suffering from prostate cancer, were phenocopies and paternal lineage transmission was unexpectedly determined in another. Risk was removed from 33 offspring and confirmed for 56. CONCLUSIONS: Complex themes associated with genetic testing are confirmed and the spectrum extended. Men appear to understand the importance of participating in this process. Methods of avoiding adverse reactions merit further study along with other aspects of the process.  相似文献   
53.
Accepted 12 September 1996
OBJECTIVE—To evaluate the impact of childhood atopic eczema on families and assess the personal financial cost of its management.
DESIGN—Cross sectional survey.
SETTING—Paediatric dermatology and paediatric diabetology outpatient clinics.
PATIENTS—Parents of 48 randomly selected children with atopic eczema and 46 with insulin dependent diabetes mellitus.
MAIN OUTCOME MEASURES—The impact on family score, the reported cost of relevant medical treatments, medical consultations, relevant hospitalisation, and income loss.
RESULTS—Families of children with moderate or severe atopic eczema had a significantly higher impact on family score than families of diabetic children. A conservative estimate of the annual personal financial cost of managing mild, moderate, and severe eczema was Aus$330, 818, and 1255, respectively. The financial cost to the community for the management of atopic eczema in the study groups was greater. The personal financial cost of managing eczema was greater than for asthma.
CONCLUSION—Childhood atopic eczema has a profound impact on the social, personal, emotional, and financial perspectives of families.

  相似文献   
54.
Type I insulin-like growth factor receptor function in breast cancer   总被引:6,自引:0,他引:6  
Experimental evidence suggests an important role of the type I IGF receptor (IGF-IR) in breast cancer development. Breast tumors and breast cancer cell lines express the IGF-IR. IGF-IR levels are higher in cancer cells than in normal breast tissue or in benign mammary tumors. The ligands of the IGF-IR are potent mitogens promoting monolayer and anchorage-independent growth of breast cancer cells. Interference with IGF-IR activation, expression, or signaling inhibits growth and induces apoptosis in breast cancer cells. In addition, recent studies established the involvement of the IGF-IR in the regulation of breast cancer cell motility and adhesion. We have demonstrated that in MCF-7 cells, overexpression of the IGF-IR promotes E-cadherin-dependent cell aggregation, which is associated with enhanced cell proliferation and prolonged survival in three-dimensional culture.The expression or function of the IGF-IR in breast cancer cells is modulated by different humoral factors, such as estrogen, progesterone, IGF-II, and interleukin-1. The IGF-IR and the estrogen receptor (ER) are usually co-expressed and the two signaling systems are engaged in a complex functional cross-talk controlling cell proliferation.Despite the convincing experimental evidence, the role of the IGF-IR in breast cancer etiology, especially in metastatic progression, is still not clear. The view emerging from cellular and animal studies is that abnormally high levels of IGF-IRs may contribute to the increase of tumor mass and/or aid tumor recurrence, by promoting proliferation, cell survival, and cell-cell interactions. However, in breast cancer, except for the well established correlation with ER status, the associations of the IGF-IR with other prognostic parameters are still insufficiently documented.  相似文献   
55.
Enteroclysis is now widely used for examining the jejunum and ileum. The technique is ideal for demonstrating the extent and severity of disorders that cause morphological changes to the small intestine. In this review many non-neoplastic small intestinal disorders as demonstrated by enteroclysis are described and illustrated. Received: 22 June 1999; Accepted: 28 July 1999  相似文献   
56.
BACKGROUND: Altered transendothelial migration and delayed apoptosis of neutrophils (PMN) have been implicated as contributing to infection in patients with gram-negative sepsis. Macrophage inflammatory protein 2 (MIP-2) signals PMN immigration and may alter other PMN functions. We tested the hypothesis that sequential endotoxin challenge in vivo alters PMN apoptosis and chemotactic responses. MATERIALS AND METHODS: Endotoxemia was induced in male Wistar rats (250 g) via intraperitoneal (IP) administration of LPS (4 mg/kg). After 18 h, intratracheal (IT) injection of LPS (400 microg/kg) was performed. Control animals received saline injections. Four hours after IT-LPS, circulating and bronchoalveolar lavage (BAL) PMN were isolated. PMN yields were calculated, and apoptosis was quantified after 18 h in culture by annexin V-fluorescein isothiocyanate FACS analysis. BAL MIP-2 concentrations were determined by ELISA. PMN chemotaxis to MIP-2 and IL-8 was determined using a fluorescent in vitro migration assay. RESULTS: Endotoxemia (IP-LPS) significantly decreases BAL PMN yield in response to an in vivo IT-LPS challenge. IT-LPS inhibits BAL PMN apoptosis to the same extent as sequential IP/IT-LPS. Alveolar MIP-2 concentrations are similar in the two groups. In vitro migration to IL-8 and MIP-2 was inhibited in PMN from endotoxemic versus control animals. CONCLUSIONS: These data demonstrate that endotoxemia inhibits PMN migration despite similar MIP-2 concentrations in the alveolus. Sequential insults do not affect the inhibition of apoptosis. In vitro, PMN from endotoxemic animals display impaired chemotaxis to MIP-2 and interleukin-8. This may result in an inadequate host defense that contributes to increased ICU-acquired pneumonia in septic patients.  相似文献   
57.
To determine whether the percentage calculated by dividing the amplitude of postexcision direct facial nerve stimulus responses (at pontomedullary junction) by the amplitude of distal ipsilateral transcutaneous (stylomastoid region) maximal stimulus responses and response amplitude progression by increasing stimulus intensities have predictive value for determining normal or near-normal (House-Brackmann Grade 1 or 2) immediate postoperative facial nerve function. STUDY DESIGN: Intraoperative recordings of three muscle groups: 1) frontalis, 2) orbicularis oculi, and 3) orbicularis oris. Postexcision direct facial nerve stimulation at the pontomedullary junction and transcutaneous maximal facial nerve stimulation at the ipsilateral stylomastoid region and their associated response amplitudes were recorded. SETTING: Tertiary referral center. PATIENTS AND METHODS: Patients who underwent acoustic neuroma surgery from January 2004 to March 2006 with intraoperative facial nerve monitoring and an intact facial nerve after tumor excision were included. Recordings were available for 38 patients. RESULTS: With a stimulus intensity of 0.3 mA at the root exit zone, there was an 81% positive predictive value in patients that exhibited a compound action potential of greater than 20% of maximum (sensitivity, 81%). This increased to 93% when the compound action potential was greater than 50% of maximum. When the amplitude increase was greater than 5 microV, there was a 77% positive predictive value (sensitivity, 87%). CONCLUSION: The percentage of the response amplitude of direct facial nerve stimulation at the pontomedullary junction when compared with the maximum response amplitude of ipsilateral transcutaneous stimulation at the stylomastoid foramen is a good predictor of normal to near-normal immediate postoperative facial nerve function. Progression of amplitude response also seems to be a good predictor of normal to near-normal immediate postoperative facial nerve function.  相似文献   
58.
Thrombotic thrombocytopenic purpura (TTP) is an acute, life‐threatening illness with disseminated platelet‐rich thromboses of small vessels that variably presents with the classic clinical “pentad” of microangiopathic hemolytic anemia, thrombocytopenia, fever, altered mental status, and acute kidney injury. Most cases are caused by an acquired autoantibody to ADAMTS13, a metalloproteinase that cleaves large von Willebrand Factor (vWF) multimers. The mainstay of treatment is daily therapeutic plasma exchange (TPE), sometimes with adjunctive pharmacologic immunosuppression. TPE is generally continued until the platelet count is greater than 150 × 103/µL and the lactate dehydrogenase is near normal for 2‐3 consecutive days. Unfortunately, there is no clear guidance for when thrombocytopenia is refractory for a prolonged period of time. The following case describes such a scenario in which consecutive ADAMTS13 activity and inhibitor levels were used to guide the decision to stop treatment with TPE in a patient who failed to recover their platelet count.  相似文献   
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