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121.
The patellofemoral (PF) joint plays an essential role in knee function, but little is known about the in vivo loading conditions at the joint. We hypothesized that the forces at the PF joint exceed the tibiofemoral (TF) forces during activities with high knee flexion. Motion analysis was performed in two patients with telemetric knee implants during walking, stair climbing, sit‐to‐stand, and squat. TF and PF forces were calculated using a musculoskeletal model, which was validated against the simultaneously measured in vivo TF forces, with mean errors of 10% and 21% for the two subjects. The in vivo peak TF forces of 2.9–3.4 bodyweight (BW) varied little across activities, while the peak PF forces showed significant variability, ranging from less than 1 BW during walking to more than 3 BW during high flexion activities, exceeding the TF forces. Together with previous in vivo measurements at the hip and knee, the PF forces determined here provide evidence that peak forces across these joints reach values of around 3 BW during high flexion activities, also suggesting that the in vivo loading conditions at the knee can only be fully understood if the forces at the TF and the PF joints are considered together. © 2011 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 30:408–415, 2012  相似文献   
122.
AIM:To evaluate changes in colorectal cancer(CRC) survival over the last 20 years.METHODS:We compared two groups of consecutive CRC patients that were prospectively recruited:Group Ⅰincluded 1990 patients diagnosed between 1980 and 1994.GroupⅡincluded 871 patients diagnosed in 2001.RESULTS:The average follow up time was 21 mo(1-229)for GroupⅠand 50 mo(1-73.4)for GroupⅡ.Overall median survival was significantly longer in Group Ⅱthan in GroupⅠ(73 mo vs 25 mo,P<0.001)and the difference was significant for all ...  相似文献   
123.
BackgroundIn high-income settings, delays from breast cancer (BC) diagnosis to initial treatment worsen overall survival (OS). We examined how time to BC treatment initiation (TTI) impacts OS in South Africa (SA).MethodsWe evaluated women enrolled in the South African BC and HIV Outcomes study between July 1, 2015 and June 30, 2019, selecting women with stages I-III BC who received surgery and chemotherapy. We constructed a linear regression model estimating the impact of sociodemographic and clinical factors on TTI and separate multivariable Cox proportional hazard models by first treatment (surgery and neoadjuvant chemotherapy (NAC)) assessing the effect of TTI (in 30-day increments) on OS.ResultsOf 1260 women, 45.6% had upfront surgery, 54.4% had NAC, and 19.5% initiated treatment >90 days after BC diagnosis. Compared to the surgery group, more women in the NAC group had stage III BC (34.8% vs 81.5%). Living further away from a hospital and having hormone receptor positive (vs negative) BC was associated with longer TTI (8 additional days per 100 km, P = .003 and 8 additional days, P = .01, respectively), while Ki67 proliferation index >20 and upfront surgery (vs NAC) was associated with shorter TTI (12 and 9 days earlier; P = .0001 and.007, respectively). Treatment initiation also differed among treating hospitals (P < .0001). Additional 30-day treatment delays were associated with worse survival in the surgery group (HR 1.11 [95%CI 1.003-1.22]), but not in the NAC group.ConclusionsDelays in BC treatment initiation are common in SA public hospitals and are associated with worse survival among women treated with upfront surgery.  相似文献   
124.
Aneurysmal bone cyst (ABC) is a benign lesion that often starts off the metaphysis of long bones and which, as it grows, may blow out bone. Only 3%-6% of cases are located in the skull. Spontaneous recovery has been reported. These cases occur more often in adults and in pelvic locations. Spontaneous regression at the skull level remains a very rare entity and few cases were described in the literature. Here, the authors report another case of spontaneous rapid regression of ABC of the skull in a 7-year-old boy revealed by gradually increasing painless hard swelling in the right frontal bone region with rapid spontaneous regression within 15 days. The authors will also proceed with an overview concerning this rare entity.  相似文献   
125.
As cardiovascular pathology grows in numbers, research into the discovery of new chemokine biomarkers should not be neglected, as they seem to be paramount in atherosclerosis prevention and its early detection. Chemokines attract and activate leukocytes and are well recognized in the environment of inflammatory response. MCP-1 is a valuable chemokine whose potential to become a new crucial atherosclerosis marker is surely worth investigating. Since quantities of MCP-1 found in lesions are as low as immeasurable, we propose the use of an immunohistochemical method for the quantification of MCP-1 levels in atherosclerotic lesions. Additionally, serum levels of MCP-1 can be measured by commercially available immunoassays. Proposed MCP-1 concentration increase may explain the acceleration in lesion’s atherosclerosis progression as chemokine activation occurs once they bind to specific ligands. If proven, this hypothesis would indicate the need for further studies in order to objectively link the increased MCP-1 expression with carotid restenosis.  相似文献   
126.
AIM: To investigate the clinical impact of capsule endoscopy (CE) after an obscure gastrointestinal bleeding (OGIB) episode, focusing on diagnostic work-up, follow-up and predictive factors of rebleeding.METHODS: Patients who were referred to Hospital del Mar (Barcelona, Spain) between 2007 and 2009 for OGIB who underwent a CE were retrospectively analyzed. Demographic data, current treatment with non-steroid anti-inflammtory drugs or anticoagulant drugs, hemoglobin levels, transfusion requirements, previous diagnostic tests for the bleeding episode, as well as CE findings (significant or non-significant), work-up and patient outcomes were analyzed from electronic charts. Variables were compared by χ2 analysis and Student t test. Risk factors of rebleeding were assessed by Log-rank test, Kaplan-Meier curves and Cox regression model.RESULTS: There were 105 patients [45.7% women, median age of 72 years old (interquartile range 56-79)] and a median follow-up of 326 d (interquartile range 123-641) included in this study. The overall diagnostic yield of CE was 58.1% (55.2% and 63.2%, for patients with occult OGIB and overt OGIB, respectively). In 73 patients (69.5%), OGIB was resolved. Multivariate analysis showed that hemoglobin levels lower than 8 g/dL at diagnosis [hazard ratios (HR) = 2.7, 95%CI: 1.9-6.3], patients aged 70 years and above (HR = 2.1, 95%CI: 1.2-6.1) and significant findings in CE (HR = 2.4, 95%CI: 1.1-5.8) were independent predictors of rebleeding.CONCLUSION: One third of the patients presented with rebleeding after CE; risk factors were hemoglobin levels < 8 g/dL, age ≥ 70 years or the presence of significant lesions.  相似文献   
127.
128.
Malignancy is one of the comorbidities linked to golimumab, a biological TNF-α blocker. In this systematic review and meta-analysis, we searched different databases and analyzed original publications to elucidate the remaining open question about the real association of malignancies with golimumab therapy. The most frequent cancer in patients treated with golimumab, in association or not with methotrexate, is the lung adenocarcinoma. However, lymphoma is not very commonly represented in these patients. We show that there is no major and evident risk of malignancies associated with golimumab in current scientific literature. An increased risk of malignancies may be associated with golimumab, but this warrants further clinical confirmation. Also, this risk mentioned in different studies must be taken with caution because of number of limits and biases.  相似文献   
129.
130.
Background: About 30–50 % of rosacea patients have ocular involvement. The symptoms range from a foreign‐body sensation to conjunctivitis or blepharitis and may even include severe corneal ulcerations. Systemic treatment is generally with tetracycline. Side effects can occur with the usual antimicrobial dose. Patients and Methods: In a retrospective study, seven patients were evaluated who had been treated for ocular rosacea with a sub‐antimicrobial dose of doxycycline 40 mg in a slow‐release form (Oraycea®). The responses were evaluated on the basis of clinical findings. Results: Seven patients with an average age of 63 took slow release doxycycline 40 mg every day for at least two months. In five patients, other systemic drugs had already failed. All patients experienced a clear improvement in their ocular rosacea after an average of 2.29 months of treatment. One patient had complete clearance and another had almost complete clearance. None of the patients experienced side effects. Conclusions: A sub‐antimicrobial dose of slow release doxycycline 40 mg daily is an effective long‐term therapy for ocular rosacea. It is not associated with the side effects of long‐term antibiotic therapy or the risk of resistance.  相似文献   
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