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991.
992.
Hinged elbow external fixation for severe elbow contracture   总被引:2,自引:0,他引:2  
BACKGROUND: When it was first introduced, it was hoped that hinged external fixation with a built-in gear mechanism for applying passive motion and static progressive stretch by turning a dial would improve the arc of ulnohumeral motion, by gradually stretching contracted muscles, after open release of a severe elbow contracture. METHODS: Forty-two patients were evaluated at an average of thirty-nine months after operative release of a severe posttraumatic elbow contracture (defined as < or =40 degrees of motion). Twenty-three patients had been treated, during the early part of the study, with a hinged external fixator that incorporated a worm gear to apply static progressive stretch postoperatively. These patients were compared with nineteen patients who had been treated without hinged external fixation during the later part of the study, when the hinge was used less frequently. The operative techniques did not otherwise change during the study period. Demographic and injury characteristics as well as associated problems were comparable between the two groups. RESULTS: The average gain in the range of motion after the index procedure was 89 degrees in the patients treated with a hinge and 78 degrees in those treated without a hinge, an insignificant difference with the numbers available (p = 0.175). Complications associated with use of the hinge included five pin-track infections, one case of pin-track osteomyelitis, one ulnar fracture through a pin site, two broken Schanz screws, and two cases of irritation of the ulnar nerve. CONCLUSIONS: Open release of a severe elbow contracture results in a substantial gain in motion, with or without hinged elbow fixation. The slightly greater improvement in motion provided by the hinge does not justify the associated increase in risk, expense, and complications.  相似文献   
993.
BACKGROUND: Interleukin (IL)-12-producing dendritic cells (IL-12+DC) polarize T helper (Th) differentiation toward Th1, whereas IL-10+DC induce Th differentiation toward Th2. We investigated DC and plasma cytokine patterns early and late after transplantation. METHODS: Twenty-five hospitalized renal-transplant recipients without acute rejection or infection early (<40 days) posttransplant, 32 symptom-free outpatients with long-term functioning transplants (2,762+/-2,423 days posttransplant), and 17 healthy controls were studied. The intracellular production of IL-12 and IL-10 in CD11c+ CD83+ CD40+ DC was measured in freshly obtained whole blood using four-color fluorescence flow cytometry. In addition, plasma cytokine levels were investigated. RESULTS: Early and late posttransplant patients had significantly lower proportions of IL-12+DC (early: P=0.001; late: P=0.034) and lower ratios of IL-12+/IL-10+DC (early: P=0.0001; late: P<0.0001) than healthy controls. IL-10+DC (P=0.0004) and IL-12+DC (P=0.002) increased with time posttransplant in association with dose reductions of cyclosporine (IL-10+DC: P=0.003; IL-12+DC: P=0.005), methylprednisolone (IL-10+DC: P<0.0001; IL-12+DC: P=0.001) and mycophenolate mofetil (IL-10+DC: P<0.0001; IL-12+DC: P=0.004). Both IL-10+DC and IL-12+DC were associated with low plasma IL-10 (IL-10+DC: P=0.010; IL-12+DC: P=0.011) and high plasma IL-6 (IL-10+DC: P=0.001; IL-12+DC: P=0.009). IL-10+DC were also associated with high plasma levels of IL-3 (P=0.003), interferon (IFN)-gamma (P=0.014), and IL-2 (P=0.058). CONCLUSION: IL-10+DC and IL-12+DC in peripheral blood are associated with time after transplantation and dosage of immunosuppression. IL-10+DC dominate late posttransplant in the presence of Th1 plasma cytokines (high IFN-gamma and IL-2), high IL-3, and low IL-10. These findings could be a reflection of immunoregulatory processes favoring long-term allograft acceptance.  相似文献   
994.
BACKGROUND: Cytolytic induction therapy with anti-thymocyte globulin (ATG) should induce effective immunosuppression, with a low rate of rejection in the initial phase after heart transplantation. Induction therapy with ATG allows post-operative renal recovery without the negative effects of highly nephrotoxic cyclosporine levels. An increased rate of infection is a common problem, however, and has been associated with "over-immunosuppression" early after transplantation. Therefore, we investigated whether reduced T-cell-adapted ATG induction therapy could be performed without increasing the risk of graft loss by rejection and whether reductions in infection rates and costs are possible. METHODS: Between March 1999 and December 2002, T-cell-adapted ATG induction therapy with ATG (Sangstat) (1.5 mg/kg) was given to 62 heart transplant recipients (study group) starting on post-operative Days 1 to 6. T-lymphocyte sub-populations were screened daily using flow cytometry. If total lymphocytes were <100/microl (reference 1,300 to 2,300/microl), T-helper lymphocytes (CD4+) <50/microl (reference >500/microl) and T-suppressor cells (CD8+) <50/microl (reference >300/microl), then no ATG was given. Further immunosuppression was continued with triple therapy consisting of methylprednisolone, azathioprine and cyclosporine. An historic group of heart transplant recipients given a full-dose ATG regimen for 8 days served as controls. These recipients were treated with ATG (Merieux 1.5 mg/kg) until reaching monoclonal cyclosporine levels of >300 mg/dl. Additional immunosuppressive treatment did not differ. Patients in both groups received systemic antibiotics (Imipenem) peri-operatively. Results of routine endomyocardial biopsies and rates of infections were examined. RESULTS: Study group patients were older (52 +/- 10 vs 49 +/- 14 years). In the study group, mean cumulative ATG dose was reduced significantly to 596 +/- 220 mg (p < 0.05) for 3.9 +/- 1.6 days compared with 1,159 +/- 376 mg for 6.9 +/- 1.1 days in the control group. The rate of cytomegalovirus (CMV) seroconversion was 23% in the study group compared with 13% in the control group. Rate of deep sternal infections was lower in the study group (1.6% vs 3.2%). The mean rejection rate in the first 3 months was 0.4 +/- 0.7 for the study patients (185 biopsies) vs 1.1 +/- 1.7 for controls (237 biopsies). All biopsies with ISHLT Grade >2 were treated successfully with 1,000 mg of methylprednisolone intravenously for 3 days. Both groups showed a similar 1-year survival rate (study 88%, control 89%). CONCLUSIONS: T-cell-adapted ATG induction therapy can be a helpful tool for individualized immunosuppression. It is not associated with an increased rate of rejection. Lower doses of immunosuppression help to minimize the rates of infection. In addition, cytolytic induction therapy combined with reduced ATG results in significant cost reduction.  相似文献   
995.
996.
The prevention of new blood vessel growth is an increasingly attractive strategy to limit tumor growth. However, it remains unclear whether anti-angiogenesis approaches will impair wound healing, a process thought to be angiogenesis dependent. Results of previous studies differ as to whether angiogenesis inhibitors delay wound healing. We evaluated whether endostatin at tumor-inhibiting doses delayed excisional wound closure. C57/BL6J mice were treated with endostatin or phosphate-buffered solution 3 days prior to the creation of two full-thickness wounds on the dorsum. Endostatin was administered daily until wound closure was complete. A third group received endostatin, but also had daily topical vascular endothelial growth factor applied locally to the wound. Wound area was measured daily and the wounds were analyzed for granulation tissue formation, epithelial gap, and wound vascularity. Endostatin-treated mice showed a significant delay in wound healing. Granulation tissue formation and wound vascularity were significantly decreased, but reepithelialization was not effected. Topical vascular endothelial growth factor application to wounds in endostatin-treated mice resulted in increased granulation tissue formation, increased wound vascularity, and wound closure approaching that of control mice. This study shows that the angiogenesis inhibitor endostatin delays wound healing and that topical vascular endothelial growth factor is effective in counteracting this effect.  相似文献   
997.
BACKGROUND: Capsule endoscopy (CE) is a new device that enables visualization of areas of the small bowel that were previously inaccessible through other noninvasive procedures. The purpose of this study is to evaluate this new diagnostic tool and its efficacy in finding occult GI tract pathology. METHODS: A single-institution retrospective review was completed on patients undergoing CE from January 2002 to September 2004. Data evaluated included indications for CE, results of previous studies, CE findings, and complications of the CE study. RESULTS: A total of 702 CE studies in 652 patients were performed during the study period. Suspicious GI bleeding presenting as anemia, guaiac positive stools, or history of gross bleeding were the most common reasons to perform CE (75.8%). Other indications included abdominal pain (11.5%), diarrhea (3.1%), or others (9.5%). In studies performed for GI bleeding (N = 532), a source was found in 49.3% of CE studies. Arteriovenous malformation (AVM) was the most common reported finding (43.9%), followed by ulcer (24.1%), colon or gastric pathology (14.1%), mass/tumor (9.1%), and stricture (6.9%). Patients with abdominal pain (n = 81) had findings 46.9% of the time including edema/ulcer (47.4%), stricture (10.5%), mass/tumor (26.3%), gastric pathology (10.5%), AVM (2.6%), or sprue (2.6%). Patients with diarrhea (n = 22) had findings 45.5% of the time including edema/ulcer (75%), mass/tumor (12.5%), or sprue (12.5%). A total of 66 patients underwent operative exploration after a CE study at this institution either because of the observed findings or for other reasons. There were 12 (1.7%) CE studies in which the capsule was retained and required surgical removal. Pathology at the retention site included benign strictures or adhesions (n = 9, 75%), Crohn's stricture (n = 1, 8.3%) carcinoid tumor (n = 1, 8.3%), and villous adenoma (n = 1, 8.3%). CONCLUSIONS: CE is an accurate study to locate abnormalities in the GI tract that may have either been missed by previous diagnostic studies or cannot be observed through other non-invasive means. When used for diagnostic challenges such as GI bleeding with no apparent source, CE can be helpful in guiding surgical decisions in patients and thus should be integrated as part of the diagnostic workup.  相似文献   
998.
OBJECTIVE: The aim of this paper is to assess the accuracy of an algorithm implemented by PRAXIM in the SURGETICS navigation station for detection of the hip center. This study will assess the robustness and accuracy of the algorithm in various clinical situations such as those involving non-sphericity of the femoral head, motion of the pelvis during hip center detection, and restricted range of motion. MATERIALS AND METHODS: The localization of the hip center, based on kinematics, relies on the recording of n successive positions of the femoral rigid body in the localizer reference system during a passive circumduction motion of the hip joint. Therefore, the shape of the clouds of points acquired may vary from one acquisition to the next. To allow a comprehensive study of the consequences of these variations for hip center detection, we developed a simulator to generate numerous clouds of points. Results given subsequently for each test are the values of the difference between the femoral mechanical axis computed with C(c), the computed hip center, and the same axis computed with C(o), the reference hip center. RESULTS: Test 1: Sensitivity to noise. The errors ranged from 3.33 E - 12 (SD 3.29E - 12) for a noise of 0 mm to 8.18E - 1 (SD - 7.05E - 1) for a noise of 15 mm. Test 2: Sensitivity to the shape of the acquisition motion. All trajectories gave an error < 1 degrees . Test 3: Sensitivity to restricted range of motion. No value > 1 degrees was found during this test. Test 4: Sensitivity to the distance between two points of the cloud. No value > 0.5 degrees was found during this test. Test 5: Sensitivity to the number of points included in the cloud. No value > 1 degrees was found during this test. CONCLUSIONS: The Surgetics algorithm is robust to noise, can compensate for pelvic motion, and can be used even in the case of restricted range of motion.  相似文献   
999.
To evaluate the features of bone trephine biopsy involvement by non-Hodgkin lymphoma, 450 specimens were evaluated for percentage of marrow involvement, pattern of involvement, presence of germinal centers or follicular structures, and discordance with other involved sites. A subset of 197 cases was evaluated for evidence of concurrent peripheral blood involvement. Follicular grade 1 lymphoma (30.4%) was the most common type to involve the marrow, followed by diffuse large B-cell lymphoma (16.0%), mantle cell lymphoma (9.3%), low-grade B-cell lymphoma, not otherwise specified (8.7%), lymphoplasmacytic lymphoma (8.4%), follicular grade 2 lymphoma (7.1%), and mature T- and NK-cell lymphomas (6.4%). A mixed pattern of infiltration was most common, followed by paratrabecular, nodular, diffuse, and interstitial patterns. Greater than 90% of follicular lymphomas had at least a focal paratrabecular infiltration pattern, but this pattern was also seen with other lymphoma types. Interstitial disease infiltration tended to correlate with lymphoplasmacytic lymphoma but was also not specific. The presence of germinal centers or follicular structures was associated with follicular lymphoma in 88% of cases. Discordance between the bone marrow morphology and other tissue sites was observed in 24.9% of cases and was most often seen with follicular or diffuse large B-cell lymphoma. Peripheral blood involvement by lymphoma was observed in 29% of cases, found in all disease groups except for follicular grade 3 lymphoma. This study highlights the frequency of different lymphoma patterns in the marrow, limitations of primary lymphoma classification on biopsy material alone, and the relative frequency of marrow discordance and peripheral blood involvement by marrow lymphoma.  相似文献   
1000.
We assessed the long-term effect of thalamic deep brain stimulation (DBS) on motor symptoms and progression of Parkinson's disease (PD) in PD patients treated for resting and postural/action tremor. Thalamic DBS was performed in 17 patients with treatment-resistant resting and postural/action tremor. Nine patients were available for follow-up examination a mean of 5.5 years after surgery. Three had tremor-dominant PD. DBS produced marked improvement in resting and postural/action tremor in target upper extremity in all 9 patients, which persisted unchanged at the time of the last follow-up visit 5.5 years after surgery. PD severity with DBS 'on' and 'off' 1 year after surgery was compared to PD severity at the last follow-up visit using UPDRS (Unified Parkinson's Disease Rating Scale) III motor scores and individual motor item subscores. Patients were tested while on medication. There was no significant worsening of tremor, rigidity, speech, postural stability, gait, or axial bradykinesia with DBS either on or off at the last follow-up visit compared to the 12-month visit. UPDRS III motor scores were unchanged. However, global assessment of PD progression and increased mean L-dopa dose and L-dopa equivalent daily dose at the time of last follow-up visit indicated that a progression of PD had occurred.  相似文献   
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