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51.
Summary Quantitative finger nailfold capillary microscopy was performed in 25 patients with type I diabetes and in 27 healthy control subjects. In the last consecutive 6 patients and 7 controls of these populations, finger nailfold biopsies were taken. Measurements of loop width as an in vivo parameter for deformities of the capillary loops showed significantly higher values in diabetic patients than in controls. Histopathological examination showed markedly and significantly increased deposition of collagen in nailfold dermal papillae of the diabetic patients. The deposition of collagen was positively correlated with the number of capillary endothelial cells in the nailfold dermal papillae and with the size of the papillae in diabetic patients. It is concluded that, in addition to deformity of nailfold capillaries, collagen deposition may also be a sign of metabolic disturbance and perhaps of proliferation of capillary endothelial cells in diabetic microangiopathy.Supported by the Swiss National Fund for Scientific Research, grant number 3.904-0.86  相似文献   
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香烟烟雾提取物致小鼠生殖细胞的遗传学损伤   总被引:5,自引:1,他引:4  
目的:研究香烟烟雾提取物对小鼠生殖细胞染色体和精子的影响,方法:给雄性小鼠腹腔注射不同剂量的香烟烟雾提取物,观察其精原细胞染色体畸变及精子畸形的情况,结果:精原细胞染色体畸变率及精子畸形率均增高,精子畸形率增高的程度大于精原细胞染色体畸变率。结论:香烟烟雾提取物可致雄性小鼠生殖细胞染色体畸变和精子畸形。  相似文献   
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BackgroundPatients with adverse spinopelvic mobility have higher complication rates following total hip arthroplasty (THA). Risk factors include a stiff lumbar spine, standing posterior pelvic tilt ≤ ?10°, and a severe sagittal spinal deformity (pelvic incidence minus lumbar lordosis mismatch ≥20°). The purpose of this study is to define the spinopelvic risk factors and quantify the prevalence of risk factors for pathologic spinopelvic mobility.MethodsA retrospective cohort analysis from January 2014 to February 2020 was performed on a multicenter series of 9414 primary THAs by 168 surgeons, all with preoperative spinopelvic measurements in the supine, standing, and flex-seated positions. All patients were included. The prevalence of adverse spinopelvic mobility and frequency of each spinopelvic risk factor was calculated.ResultsThe cohort was 52% female, 48% male, with an average age of 65 years. Thirteen percent of patients exhibited adverse spinopelvic mobility and 17% had one or more of the 3 risk factors. Adverse mobility was found in 35% of patients with at least 1 risk factor, 47% with at least 2 risk factors, and 57% with all 3 risk factors.ConclusionForty-six percent of patients had spinopelvic pathology driven by one or more of the risk factors. Number of risk factors present and risk of adverse spinopelvic mobility were positively correlated, with 57% of patients with all 3 risk factors exhibiting adverse spinopelvic mobility. Although this study defines the prevalence of these risk factors in this highly selected cohort, it does not report incidence in a general THA population.Level of EvidencePrognostic Level IV.  相似文献   
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BackgroundThe present article analyzes the association of the functional anterior cruciate ligament (ACL) status and the overall varus deformity and coronal tibiofemoral subluxation (CTFS) in varus OA of the knee.MethodsOne hundred consecutive knees with varus OA in 84 patients were prospectively included. Knees were divided into two groups, in accordance with the ACL status (functionally sufficient or insufficient). All included patients were potential candidates for unicompartmental knee arthroplasty with predominantly medial compartment OA. Knees with Kellgren/Lawrence ≥ grade 3 in the lateral compartment were excluded leaving 79 knees to be included in this study. Mechanical varus deformity and CTFS were evaluated on AP radiographs and valgus stress radiographs, and compared between the two groups.ResultsKnees with a functionally insufficient ACL had significantly more varus deformity on hip-to-ankle AP standing radiographs (P = .001) and on valgus stress radiographs (P = .017). CTFS on AP standing radiographs was significantly higher (P = .045) in knees with a functionally insufficient ACL. Seventy-three percent (8/11) of the ACL-insufficient knees had a varus deformity of ≥10° and 64% (7/11) of ACL-insufficient knees had CTFS ≥ 6mm. By contrast, only one patient (2%, 1/41) with an insufficient ACL had< 10° varus deformity and a CTFS of < 6mm.ConclusionFunctional ACL insufficiency in osteoarthritic varus knees is associated with greater varus deformity and more advanced CTFS. Seventy-three percent of ACL-insufficient knees had a varus deformity of ≥10° and 64% of ACL-insufficient knees a CTFS of ≥ 6mm. In the work-up for medial unicompartmental knee arthroplasty, functional ACL insufficiency is likely in knees with varus deformity of ≥10° and CTFS of ≥ 6mm.  相似文献   
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BackgroundPatients with a preoperative varus deformity >8 degrees are at increased risk of aseptic loosening after total knee arthroplasty. This study analyzes the effect of a tibial stem on the rate of aseptic loosening in patients with a severe preoperative varus deformity.MethodsPatients with a preoperative varus deformity of >8 degrees and 2-year minimum follow-up with a stemmed tibial component (n = 67) were matched 1:2 to patients with a similar preoperative varus deformity with a standard tibial component (n = 134). Radiolucent lines were measured on the tibia at 6 weeks, 1 year, and 2 years postoperatively using the Knee Society Radiographic Evaluation System. Failure was defined as revision due to aseptic loosening of the tibial component. Outcomes were evaluated using Student’s t-tests and log-rank tests.ResultsPatients with tibial stems had greater preoperative deformity (12.9 vs 11.3 degrees, P = .004). There was no difference in postoperative alignment (1.7 vs 2.1 degrees varus, P = .25) or tibial component angle (1.8 vs 2.1 degrees varus, P = .33). Patients with stems were more likely to have more constraint (44.8% vs 1.5%, P < .001). Progression of radiolucent lines >2 mm was observed in 17.6% (23/134) vs 5.97% (4/67) of patients in the stem group (P = .03). Rates of aseptic loosening were lower in the stem group (0% vs 5.15%, P = .05).ConclusionDespite worse preoperative deformity and higher utilization of constraint, tibial stem use in patients with severe preoperative varus deformity resulted in lower rates of aseptic loosening. Prophylactic use of stems in these patients may help increase implant survival.  相似文献   
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BackgroundInjuries involving upper cervical spine are serious and fatal injuries which are associated with alteration of normal occipital–cervical anatomy. These injuries may result in permanent neurologic deficits or neck deformity if not treated in a timely and appropriate manner.ObjectiveTo evaluate the outcomes of neglected upper cervical spine injuries treated by various methods.Study designRetrospective study.Materials and methodsTwelve patients attending ER or OPD with a history of neck trauma and who were diagnosed with fractures and fracture dislocations C1 and C2 were included in the study. Fresh injuries sustained within a week were excluded from study. The outcomes were measured in terms of improvement in VAS, ODI Scores and correction of the neck deformity. Surgical parameters like duration of surgery and blood loss were also observed.ResultsEleven males and one female. The mean age was 40.9 ± 16.9 (07–67 years). Eleven patients underwent posterior instrumentation, while one patient was treated anteriorly. The mean delay in presentation was 28 ± 8.67 days (15–42 days). The mean duration of surgery was 188.3 ± 34.35 min (120–240 min), average blood loss was 350 ± 111.8 ml (150–600 ml). The mean VAS improved from 8.45 ± 0.89 to 3.9 ± 0.51 (p < 0.05). The mean ODI Pre-operatively was 88.45 ± 5.89 which improved to 31.9 ± 4.01 (p < 0.05). The neck deformity/torticollis was corrected in all the patients.ConclusionsNeglected upper cervical spine injuries are difficult to treat and a posterior approach is helpful in reducing the subluxations indirectly and to obtain a posterior fusion.  相似文献   
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《Neuro-Chirurgie》2021,67(2):152-156
IntroductionComplex spinal surgery is known to be at risk of complications. Surgical site infection is a serious complication in spine surgery and its frequency is significantly increased in adult spinal deformity correction. The aim of this study is to identify patients’ characteristics and risk factors of surgical site infection (SSI) following an osteotomy.MethodsThis is a single-center retrospective study of patients who underwent an osteotomy between January 2015 and December 2017. Surgical site infection diagnosis was based upon patient's clinical evidence of infection, biologic parameters, microbiological criteria and/or image findings.ResultsIn total, 102 patients were eligible and 70 were women (68.6%). Mean age was 65 years old (27–83 years) and mean body mass index (BMI) was 26.14 kg.m−2 (18.4–44.1). Eleven patients were in the SSI group and 91 in the No-SSI group. The mean Schwab grade was 1.5 (1–4) in the SSI group vs. 1.4 (1–5) in the No-SSI group (P = 0.435). The mean operative time was on 201.9 minutes (67–377). Mean length of stay was 20.6 days (10–73) in the SSI group vs. 15 days (5–44) in the No-SSI group (P = 0.041). Favorable outcome was found in 10 patients (90.9%) in the SSI group.ConclusionCorrection surgery for adult spinal deformity with osteotomies carries a high risk of complications specially SSI. Identification of risk factors, prevention and medical management of SSI should be well assessed.  相似文献   
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