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71.
目的 探讨股骨近端锁定加压钢板(LCP)内固定治疗股骨转子间骨折的临床疗效.方法 采用股骨近端LCP治疗23例股骨转子间骨折的患者.随访观察骨折愈合时间,按Harris评分标准评价疗效.结果 23例均获随访,时间6~12(9±1.4)个月.骨折愈合时间14~20(17±1.7)周.髋关节Harris评分:优13例,良9例,一般1例.结论 股骨近端LCP内固定治疗股骨转子间骨折创伤小、出血少、对骨膜影响小,符合解剖形态,临床疗效满意.  相似文献   
72.
OBJECTIVE: To estimate the frequency of conditions associated with lower urinary tract symptoms (LUTS, typically included when assessing benign prostatic hyperplasia, BPH), as other causes of LUTS should be excluded when diagnosing BPH, using data from the Olmsted County Study of Urinary Symptoms and Health Status among Men. SUBJECTS AND METHODS: During 1989-91, Caucasian men aged 40-79 years were randomly selected from the Olmsted County population. Before contact, eligibility was determined by reviewing the community medical records. Baseline exclusion criteria included comorbid pre-existing conditions or treatments, e.g. prostate, bladder or lower back surgery, bladder neck contracture or cancer, diabetes with lower extremity amputation, and neurological diseases, including Parkinson's disease, amyotrophic lateral sclerosis, multiple sclerosis, tabes dorsalis and stroke. Men with these conditions were excluded from the Olmsted County Study at baseline, because these conditions are potentially associated with LUTS. RESULTS: Of the 5100 randomly sampled men, 13.4% met at least one of the pre-existing exclusion criteria. Individually, the frequency of exclusions was 7.8% for prostate cancer or surgery, 4.8% for back surgery, 1.3% for bladder surgery and 1.4% for neurological conditions. All other conditions represented <1.0% of the study exclusions. Older men were more likely to meet at least one of the exclusion criteria, with men in their fifth to eighth decade having a total exclusion frequency of 1.4%, 5.4%, 8.5% and 32.8%, respectively. The most common reason for men in their fifth decade to be excluded was lower back surgery (0.9%), whereas the most common reason in the eighth was prostate surgery (21.8%). CONCLUSIONS: In men, conditions that may contribute to LUTS, other than BPH, are prevalent in the community and increase in frequency with age. It is important that other conditions associated with LUTS be excluded before a definitive diagnosis of BPH. Any oversight in this initial evaluation can potentially result in misclassification bias, misdiagnosis and incorrect treatment of patients.  相似文献   
73.
The September 11, 2001, terrorist attacks on the World Trade Center (WTC) in New York City (9/11) had health-related consequences, including posttraumatic stress disorder (PTSD). PTSD is associated with functional impairment, which varies by symptom severity and other factors. This study aimed to identify predictors of functional impairment in individuals with low versus high PTSD symptom severity levels. WTC Health Registry enrollees exposed to 9/11 were surveyed four times between 2003 and 2015; cumulated data for individuals who endorsed at least one symptom on the PTSD Checklist–Civilian Version (PCL-C) at Wave 4 (2015–2016) were included (N = 30,287) and examined cross-sectionally. Individuals were classified based on PCL-C scores as having low/no (2–29) or high levels of PTSD symptom severity (≥ 44). Functional impairment was defined as subsequent difficulties in daily living. Among low/no PTSD severity participants, adjusted odds ratios (aORs) for the associations between functional impairment and poor self-rated health (vs. good), low social support (vs. high), and no physical activity (vs. active) were 1.23–1.92. In the same group, low versus high household income was associated with more functional impairment, aOR = 1.34, 95% CI [1.13, 1.59]. Among participants with high-level PTSD symptoms, women, aOR = 1.70, 95% CI [1.31, 2.20], and Hispanic enrollees, aOR = 1.76, 95% CI [1.31, 2.36], were more likely to report an absence of impairment. Self-rated health, social support, and physical activity emerged as important predictors of PTSD-related functional impairment across PTSD symptom severity levels, supporting clinical interventions targeting these factors.  相似文献   
74.

Objectives

The purpose of this study is to assess mIBG uptake in scar border zone and its relation with ventricular arrhythmia (VA) inducibility on electrophysiology (EP) testing using I-123 mIBG SPECT and resting Tc-99m SPECT myocardial perfusion imaging (MPI).

Methods

Forty-seven patients from a previous clinical trial were retrospectively analyzed. These patients underwent I-123 mIBG and resting Tc-99m tetrofosmin SPECT, and EP testing. Twenty-eight patients were positive (EP+) and 19 patients were negative (EP?) for inducibility of sustained (>30 seconds) VA on EP testing. MPI scar extent, border zone extent, and mIBG uptake in border zone were used to predict VA inducibility on EP testing, respectively.

Results

There was no significant difference in scar extent between the EP+ and EP? groups. The EP+ group had significantly larger border zone and lower mIBG uptake ratio in the border zone than the EP? group. Receiver operating characteristic (ROC) curve analysis showed that the prediction accuracy for border zone extent (area under ROC = 0.75) was better than scar extent (area under ROC = 0.66). The prediction accuracy was further improved (area under ROC = 0.78), when assessing mIBG uptake in the border zone.

Conclusion

A new tool has been developed to measure scar and border zone and to assess mIBG uptake in scar and border zone from combined I-123 MIBG SPECT and resting Tc-99m SPECT MPI. The mIBG uptake in the border zone predicted VA inducibility on EP testing with a promising accuracy.  相似文献   
75.
Tendon injury frequently results in the formation of adhesions that reduce joint range of motion. To study the cellular, molecular, and biomechanical events involved in intrasynovial tendon healing and adhesion formation, we developed a murine flexor tendon healing model in which the flexor digitorum longus (FDL) tendon of C57BL/6 mice was transected and repaired using suture. This model was used to test the hypothesis that murine flexor tendons heal with differential expression of matrix metalloproteases (MMPs), resulting in the formation of scar tissue as well as the subsequent remodeling of scar and adhesions. Healing tendons were evaluated by histology, gene expression via real-time RT-PCR, and in situ hybridization, as well as biomechanical testing to assess the metatarsophalangeal (MTP) joint flexion range of motion (ROM) and the tensile failure properties. Tendons healed with a highly disorganized fibroblastic tissue response that was progressively remodeled through day 35 resulting in a more organized pattern of collagen fibers. Initial repair involved elevated levels of Mmp-9 at day 7, which is associated with catabolism of damaged collagen fibers. High levels of Col3 are consistent with scar tissue, and gradually transition to the expression of Col1. Scleraxis expression peaked at day 7, but the expression was limited to the original tendon adjacent to the injury site, and no expression was present in granulation tissue involved in the repair response. The MTP joint ROM with standardized force on the tendon was decreased on days 14 and 21 compared to day 0, indicating the presence of adhesions. Peak expressions of Mmp-2 and Mmp-14 were observed at day 21, associated with tendon remodeling. At day 28, two genes associated with neotendon formation, Smad8 and Gdf-5, were elevated and an improvement in MTP ROM occurred. Tensile strength of the tendon progressively increased, but by 63 days the repaired tendons had not reached the tensile strength of normal tendon. The murine model of primary tendon repair, described here, provides a novel mechanism to study the tendon healing process, and further enhances the understanding of this process at the molecular, cellular, and biomechanical level. © 2008 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 27: 833–840, 2009  相似文献   
76.
OBJECTIVE. The objective was to determine the MR imaging findings that differentiate intact anterior cruciate ligament reconstruction graft, partial-thickness tear, and full-thickness tear, using arthroscopy as the gold standard. MATERIALS AND METHODS. Sixteen consecutive MR imaging examinations were retrospectively and independently evaluated by two musculoskeletal radiologists for primary signs (graft signal, orientation, fiber continuity, complete discontinuity, and thickness) and secondary signs (anterior tibial translation, uncovered posterior horn lateral meniscus, posterior cruciate ligament hyperbuckling, and abnormal posterior cruciate ligament line) of anterior cruciate ligament reconstruction graft tear in 15 patients with follow-up arthroscopy. Results were compared with arthroscopy, and both receiver operating characteristic curves and kappa values for interobserver variability were calculated. RESULTS. Arthroscopy revealed four full-thickness graft tears, seven partial-thickness tears, and five intact grafts. Of the primary signs, graft fiber continuity in the coronal plane and 100% graft thickness in the sagittal or coronal plane were most valuable in excluding full-thickness tear. Complete discontinuous graft in the coronal plane also was valuable in diagnosis of full-thickness tear. Of the secondary signs, anterior tibial translation and uncovered posterior horn lateral meniscus assisted in differentiating graft tear (partial or full thickness) from intact graft. The other primary and secondary signs were less valuable. Kappa values were highest for graft fiber continuity and graft discontinuity in the coronal plane. CONCLUSION. Full-thickness anterior cruciate ligament graft tear can be differentiated from partial-thickness tear or intact graft by evaluating for graft fiber continuity (coronal plane), complete graft discontinuity (coronal plane), and graft thickness (coronal or sagittal plane).  相似文献   
77.

OBJECTIVE

To determine the normal values for the presumed circle area ratio (PCAR) in a group of community‐based men, and to determine whether PCAR is associated with specific urological outcomes.

PATIENTS AND METHODS

The study was a cross‐sectional analysis among 328 Caucasian men (94% participation) residing in Olmsted County, Minnesota, USA. The PCAR was measured during prostatic ultrasonography. Lower urinary tract symptoms (LUTS) were measured using the American Urologic Association Symptom Index. The peak urinary flow rate was measured by a uroflowmeter, and the postvoid residual volume (PVR) was assessed using the BladderScanTM BVM 6500 (Verathon, Bothell, WA, USA). Correlations between PCAR and presence of LUTS, peak urinary flow rate, and PVR were determined using Spearman correlation coefficients. Unadjusted and adjusted odds ratios (ORs) were calculated using logistic regression to determine the associations between PCAR thresholds and categorical urological outcomes.

RESULTS

The median (interquartile range) PCAR was 0.85 (0.81–0.88). After adjusting for age and total prostate volume, men who had PCARs of >0.90 were more likely to have elevated overall and obstructive symptom scores (OR 2.95, 95% confidence interval 1.39–6.25, and 3.47, 1.63–7.39, respectively).

CONCLUSION

PCAR might add further information beyond total prostate volume when predicting the development of obstructive LUTS.  相似文献   
78.
OBJECTIVE—To determine the contribution of liver and viscera to splanchnic cortisol production in humans.RESEARCH DESIGN AND METHODS—D4 cortisol was infused intravenously; arterial, portal venous, and hepatic venous blood was sampled; and liver and visceral fat were biopsied in subjects undergoing bariatric surgery.RESULTS—Ratios of arterial and portal vein D4 cortisol/cortisoltotal (0.06 ± 0.01 vs. 0.06 ± 0.01) and D4 cortisol/D3 cortisol (1.80 ± 0.14 vs. 1.84 ± 0.14) did not differ, indicating that no visceral cortisol production or conversion of D4 cortisol to D3 cortisol via 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD-1) occurred. Conversely, ratios of both D4 cortisol to cortisoltotal (0.05 ± 0.01; P < 0.05) and D4 cortisol to D3 cortisol (1.33 ± 0.11; P < 0.001) were lower in the hepatic vein than in the portal vein, indicating production of both cortisol and D3 cortisol by the liver. The viscera did not produce either cortisol (−8.1 ± 2.6 μg/min) or D3 cortisol (−0.2 ± 0.1 μg/min). In contrast, the liver produced both cortisol (22.7 ± 3.90 μg/min) and D3 cortisol (1.9 ± 0.4 μg/min) and accounted for all splanchnic cortisol and D3 cortisol production. Additionally, 11β-HSD-1 mRNA was approximately ninefold higher (P < 0.01) in liver than in visceral fat. Although 11β-HSD-2 gene expression was very low in visceral fat, the viscera released cortisone (P < 0.001) and D3 cortisone (P < 0.01) into the portal vein.CONCLUSIONS—The liver accounts for all splanchnic cortisol production in obese nondiabetic humans. In contrast, the viscera releases cortisone into the portal vein, thereby providing substrate for intrahepatic cortisol production.Although it has been long known that glucocorticoids are potent regulators of glucose, fat, and protein metabolism, glucocorticoids have not been thought to cause insulin resistance in either obese or diabetic individuals because plasma concentrations do not differ from those present in lean nondiabetic subjects. However, extra-adrenal conversion of cortisone to cortisol via 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD-1) can result in high local concentrations of cortisol. This observation focused attention on the possibility that tissue-specific synthesis of glucocorticoids may contribute to the pathogenesis of insulin resistance and other components of the so called “metabolic syndrome” (1). The enzyme 11β-HSD-2 (which converts cortisol to cortisone) is present primarily in the kidney, whereas 11β-HSD-1 (which converts cortisone to cortisol) is present in both liver and adipose tissue with in vitro activity being greater in omental than subcutaneous fat deposits (25). Inhibition (6) or knockout (79) of 11β-HSD-1 in mice improves hepatic insulin action and protects against obesity and hyperglycemia. Conversely, selective overexpression of 11β-HSD-1 in adipose tissue in mice results in development of visceral obesity, hyperglycemia, hyperlipidemia, and hypertension (711).Using a novel tracer infusion method, Andrew et al. (12) demonstrated that infusion of [9,11,12,12-2H4] cortisol (D4 cortisol) in fasting, nondiabetic humans resulted in the formation of measurable amounts of plasma [9,12,12-2H3] cortisol (D3 cortisol). Because conversion of D4 cortisol to D3 cortisone by 11β-HSD-2 results in the loss of the 11 α-deuterium and the generation of D3 cortisone that in turn forms D3 cortisol when D3 cortisone is converted back to cortisol, this observation provides strong experimental evidence that the conversion of cortisone to cortisol occurs in humans (12). More recently, we used the same method in combination with the hepatic venous and leg catheterization techniques to determine the site(s) of conversion of cortisone to cortisol. Those studies (13) led to the discovery that rates of splanchnic cortisol production in healthy nondiabetic individuals equaled or even exceeded those produced by extrasplanchnic tissues (e.g., the adrenals). However, because concomitant uptake of cortisol also occurred within the splanchnic bed, only a small net amount of cortisol was released into the systemic circulation.Because portal venous blood was not sampled in those studies, we could not determine the individual contributions of the viscera and the liver to splanchnic cortisol production. We therefore addressed this question in a chronically catheterized conscious dog model that permitted simultaneous selective sampling of blood from an artery, the portal vein, and the hepatic vein during intravenous infusion of D4 cortisol (14). Surprisingly, we showed that the liver accounted for all of the splanchnic cortisol production in the dog without discernable release by the viscera. However, the dogs were lean, and it is unknown if the pattern of splanchnic cortisol production in dogs reflects that in humans. Therefore, it remained possible that visceral fat releases cortisol into the portal vein in obese humans, thereby exposing the liver to high local glucocorticoid concentrations.The present experiments addressed this question by selectively obtaining simultaneous samples of arterial, portal venous, and hepatic venous blood during a D4 cortisol infusion in severely obese subjects undergoing bariatric surgery. In addition, mRNA for the glucocorticoid receptor (NR3C1), 11β-HSD-1, and 11β-HSD-2 was measured in liver and visceral fat obtained during surgery. We report that the liver accounts for all of the splanchnic cortisol production in obese nondiabetic humans. In contrast, there was no detectible release of cortisol into the portal vein by the viscera. On the other hand, although the mRNA for 11β-HSD-2 in visceral fat was very low, the viscera released cortisone into the portal vein, thereby providing the liver with substrate for intrahepatic cortisol production.  相似文献   
79.

Purpose

To assess the potential for regeneration of the hamstring tendons after harvesting for various soft tissue reconstructive procedures, this study uses dynamic, high-resolution ultrasound to evaluate the presence of any tissue in the harvest gap and to characterize tissue functionality.

Methods

Patients who underwent ACL reconstruction using ipsilateral hamstring autograft were identified in the database of a single surgeon. Dynamic 12-MHz sonographic imaging was used to evaluate the ipsilateral and contralateral (control) semitendinosus tendons from their insertion sites to proximal muscle bellies. The presence or absence and echogenicity of tissue in the harvest defect, tissue appearance, degree of retraction of the proximal tendon stump, thickness of gap tissue, and motion of the proximal tendon stump were recorded. Data were analysed with Wilcoxon–Mann–Whitney, sign or binomial tests, with significance of P < 0.05.

Results

Eighteen knees in 15 patients (aged 17–51 years) were studied. The proximal amputated stump was retracted an average of 9.0 ± 7.6 cm (range, 0–18 cm; P = 0.0063). With dynamic testing, 9 of 15 knees demonstrated decreased excursion of the proximal tendon stump when compared to the native, contralateral muscle–tendon unit (P = 0.0039). Tissue was detected in the harvest gap in nine knees, five of which had harvest gap tissue with a disorganized appearance compared to the native tendon (P < 0.0001). Six of these nine knees had tissue in the gap demonstrating either less or no excursion with active knee flexion when compared to the native, contralateral side (P = 0.0313).

Conclusions

The presence of tissue in the harvest gap after ACL reconstruction is variable. When tissue is present, there is proximal retraction of the musculotendinous junction and disorganized appearance of the tissue that does not demonstrate normal excursion or physiological function similar to the native muscle-tendon unit.

Level of evidence

Case series, Level IV.  相似文献   
80.
BackgroundPET myocardial perfusion imaging (MPI) holds several advantages over SPECT for diagnosing coronary artery disease. The short half-lives of prevailing PET-MPI agents hamper wider clinical application of PET in nuclear cardiology; prompting the development of novel PET-MPI agents. We have previously reported on the potential of radiolabeled ammonium salts, and particularly on that of [11C]dimethyl-diphenyl-ammonium ([11C]DMDPA), for cardiac PET imaging. This study was designed to improve the radiosynthesis and increase the yield of [11C]DMDPA, characterize more meticulously the kinetics of radioactivity distribution after its injection via micro-PET/CT studies, and further explore its potential for PET-MPI.MethodsThe radiosynthetic procedure of [11C]DMDPA was improved with respect to the previously reported one. The kinetics of radioactivity distribution following injection of [11C]DMDPA were investigated in juvenile and young adult male SD rats using microPET/CT, and compared to those of [13N]NH3. Furthermore, the metabolic fate of [11C]DMDPA in vivo was examined after its injection into rats.ResultsFollowing a radiosynthesis time of 25–27 min, 11.9 ± 1.1 GBq of [11C]DMDPA was obtained, with a 43.7% ± 4.3% radiochemical yield (n = 7). Time activity curves calculated after administration of [11C]DMDPA indicated rapid, high and sustained radioactivity uptake in hearts of both juvenile and young adult rats, having a two-fold higher cardiac radioactivity uptake compared to [13N]NH3. Accordingly, at all time points after injection to both juvenile and young adult rats, image quality of the left ventricle was higher with [11C]DMDPA compared to [13N]NH3. In vivo stability studies of [11C]DMDPA indicate that no radioactive metabolites could be detected in plasma, liver and urine samples of rats up to 20 min after injection, suggesting that [11C]DMDPA is metabolically stable in vivo.ConclusionsThis study further illustrates that [11C]DMDPA holds, at least in part, essential qualities required from a PET-MPI probe. Owing to the improved radiosynthetic procedure reported herein, [11C]DMDPA can be produced in sufficient amounts for clinical use.  相似文献   
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