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91.
BACKGROUND: Retrograde intramedullary nailing is an established procedure for tibiotalocalcaneal arthrodesis. This study was conducted to see whether, and if so to what extent, nail design modifications would influence the risk to anatomic structures and the bony coverage of the nail base. METHODS: Six pairs of thawed fresh-frozen cadaver legs received two different intramedullary nails (N1: straight nail, lateral-medial tip locking; N2: valgus-curved nail, medial-lateral tip locking) under simulated operative conditions. The specimens were dissected; distances between the at-risk structures and the hardware were measured. The hindfoot axis and the volume of the intracalcaneal nail portion were determined with CT. RESULTS: At the plantar entry site, N2 was significantly farther from the flexor hallucis longus tendon (p=0.047), the medial plantar artery (p=0.026), and the lateral plantar nerve (p=0.026) than N1. The lateral-medial calcaneal locking screw of N1 damaged significantly more often the peroneus brevis tendon (p=0.03) than N2. The proximal tip-locking screw, N2, was significantly farther from the anterior tibial artery (p=0.075) and the deep (p=0.047) and superficial peroneal nerves (p=0.009) than N1; N1 was significantly farther from the great saphenous vein (p=0.075) than N2. The distal tip-locking screw, N1. damaged significantly more often the extensor digitorum longus (p=0.007), the anterior tibial artery(p = 0.04), and the deep and superficial peroneal nerves (p=0.03) than N2. CT did not show any significant changes in the hindfoot axis with either device; intracalcaneal nail volumes were similar. CONCLUSIONS: A curved nail can increase the distance to at-risk plantar structures. Medial-lateral nail-tip locking appears to have less risk to neurovascular structures. CLINICAL RELEVANCE: Safer retrograde intramedullary nailing for tibiotalocalcaneal fusion requires knowledge of the structures at risk and appropriate operative technique.  相似文献   
92.
OBJECTIVE: To investigate the age-stratified prevalence of erectile dysfunction (ED) and its comorbidities, and to assess the population's knowledge, utilization, and general attitude towards the treatment for ED. SUBJECTS AND METHODS: In all, 10 000 men received a 35-item questionnaire including the International Index of Erectile Function (IIEF) and sociodemographic questions regarding life style, comorbidities, quality of sexual life and knowledge or experience of ED therapy. In all, 3124 responses were included (31.2%), 2499 men lived in well established partnerships and were assessed as the basic study group. RESULTS: In the entire population the prevalence rate of ED was 40.1%. However, although known, medical treatment for ED is used only by a minority of affected men. The prevalence of ED was independently associated with age, peripheral arterial occlusive disease, hypertension, ischaemic heart disease, diabetes mellitus, and liver diseases. Correlations between sexual quality of life (QoL) and ED were statistically significant (P < 0.01) and moderate to strong (absolute values: Spearman's rho 0.35-0.76). Although 96% of the study population knew at least one phosphodiesterase type 5 (PDE5) inhibitor by name, only 53% considered taking the medication and only 9% of the men with ED had had experience with available PDE5 inhibitors. CONCLUSIONS: The sexual QoL was significantly reduced by ED. Despite high levels of awareness and general acceptance of oral medication for ED, experience with PDE5 inhibitors was low. Further investigation is required to evaluate the general impact of ED on sexual QoL and the need or wish for treatment.  相似文献   
93.
This case report assessed quality of life, activities of daily living, motor symptoms, functional ability, neuromuscular parameters and mRNA expression of selected genes related to muscle protein synthesis and degradation in a patient with Multiple System Atrophy (MSA). The patient underwent resistance training with instability devices (i.e., bosu, dyna disk, balance disk, Swiss ball) for six months twice a week. After the six months training, the patient’s left and right quadriceps muscle cross-sectional area and leg press one-repetition maximum increased 6.4%, 6.8%, and 40%, respectively; the patient’s timed up and go, sit to stand, dynamic balance, and activities of daily living improved 33.3%, 28.6%, 42.3%, and 40.1%, respectively; the patient’s severity of motor symptoms and risk of falls decreased 32% and 128.1%, respectively. Most of the subscales of quality of life demonstrated improvements as well, varying from 13.0% to 100.0%. mRNA expression of mechanogrowth factor and mammalian target of rapamycin increased 12.7-fold and 1.5-fold, respectively. This case report describes likely the first nonpharmacological therapeutic tool that might be able to decrease the severity of motor symptoms and risk of falls, and to improve functional ability, neuromuscular parameters, and quality of the life in a patient with MSA.

Key points

  • Six months of resistance training with instability alleviate the MSA-related effects and improve the quality of life in a patient with MSA.
  • High complexity exercise intervention (i.e., resistance training with instability) may be very beneficial to individuals with impaired motor control and function as MSA patients.
  • Caution should be exercised when interpreting our findings as they cannot be generalized to the entire MSA population and they do not allow establishing causal conclusions on the effects of this mode of exercise on MSA.
Key words: Exercise training, risk of falls, motor symptoms, cross-sectional area  相似文献   
94.
OBJECTIVE: The purpose of this study was to compare mangafodipir trisodium-enhanced MR imaging performed with a phased array coil and contrast-enhanced single-detector helical CT for accuracy in the detection and local staging of pancreatic adenocarcinoma and in the differentiation between cancer and focal pancreatitis. SUBJECTS AND METHODS: Forty-two patients with suspected pancreatic masses underwent contrast-enhanced helical CT and mangafodipir trisodium-enhanced MR imaging at 1.5 T. The images were assessed for the presence or absence of tumors; characterization of masses; and presence of vascular invasion, lymph node metastases, or liver metastases. Imaging findings were correlated with findings at laparotomy, laparoscopy, biopsy, or follow-up. RESULTS: Focal masses were present in 36 patients (cancer, n = 26; focal pancreatitis, n = 7; other, n = 3). The sensitivity for lesion detection of MR imaging was 100% and of CT, 94%. Two small malignant lesions were missed on CT. For the diagnosis of tumor nonresectability, the sensitivity of MR imaging and CT was 90% and 80%, respectively. Liver metastases were missed on MR imaging in one of the eight patients and on CT in four. For differentiation between adenocarcinoma and nonadenocarcinoma, the sensitivity of MR imaging was 100% (positive predictive value, 90%; negative predictive value, 100%), and the sensitivity of CT was 92% (positive predictive value, 80%; negative predictive value, 67%). Receiver operating characteristic analysis revealed that the mean area under the curve for MR imaging was 0.920 and for CT, 0.832 (not significant). CONCLUSION: Mangafodipir trisodium-enhanced MR imaging is as accurate as contrast-enhanced helical CT for the detection and staging of pancreatic cancer but offers improved detection of small pancreatic metastases and of liver metastases compared with CT.  相似文献   
95.
96.
Background: Cerebrovascular carbon dioxide reactivity during high-dose remifentanil infusion was investigated in volunteers by measurement of regional cerebral blood flow (rCBF) and mean CBF velocity (CBFv).

Methods: Ten healthy male volunteers with a laryngeal mask for artificial ventilation received remifentanil at an infusion rate of 2 and 4 [mu]g [middle dot] kg-1 [middle dot] min-1 under normocapnia, hypocapnia, and hypercapnia. Stable xenon-enhanced computed tomography and transcranial Doppler ultrasonography of the left middle cerebral artery were used to assess rCBF and mean CBFv, respectively. If required, blood pressure was maintained within baseline values with intravenous phenylephrine to avoid confounding effects of altered hemodynamics.

Results: Hemodynamic parameters were maintained constant over time. Remifentanil infusion at 2 and 4 [mu]g [middle dot] kg-1 [middle dot] min-1 significantly decreased rCBF and mean CBFv. Both rCBF and mean CBFv increased as the arterial carbon dioxide tension increased from hypocapnia to hypercapnia, indicating that cerebrovascular reactivity remained intact. The average slopes of rCBF reactivity were 0.56 +/- 0.27 and 0.49 +/- 0.28 ml [middle dot] 100 g-1 [middle dot] min-1 [middle dot] mmHg-1 for 2 and 4 [mu]g[middle dot]kg-1[middle dot]min-1 remifentanil, respectively (relative change in percent/mmHg: 1.9 +/- 0.8 and 1.6 +/- 0.5, respectively). The average slopes for mean CBFv reactivity were 1.61 +/- 0.95 and 1.54 +/- 0.83 cm [middle dot] s-1 [middle dot] mmHg-1 for 2 and 4 [mu]g [middle dot] kg-1 [middle dot] min-1 remifentanil, respectively (relative change in percent/mmHg: 1.86 +/- 0.59 and 1.79 +/- 0.59, respectively). Preanesthesia and postanesthesia values of rCBF and mean CBFv did not differ.  相似文献   

97.
Prolactin modulates survival and cellular immune functions in septic mice   总被引:2,自引:0,他引:2  
BACKGROUND: The immunomodulatory properties of the pituitary hormone prolactin have been demonstrated. It was proposed that prolactin is important in maintaining normal immune response in several pathological states. We investigated the effect of prolactin administration on the survival and cellular immune functions during systemic inflammation. MATERIALS AND METHODS: Male NMRI mice were subjected to laparotomy (LAP) or sepsis induced by cecal ligation and puncture (CLP). Mice were treated with either saline (LAP/saline; CLP/saline) or prolactin (LAP/PRL, CLP/RPL; 4 mg/kg s.c.). Survival of septic mice was determined 24 and 48 h after CLP. Forty-eight hours after the septic challenge, the proliferative capacity, cytokine release (IL-2, IL-6, IFN-gamma) and apoptosis of splenocytes were determined. Additionally, monitoring of circulating leukocyte distribution was performed (WBC; CD3+, CD4+, CD8+, B220+, NK1.1+, F4/80+ cells by FASCan). RESULTS: CLP was accompanied by a mortality of 47% and induced a decrease in splenocyte proliferation and apoptosis rate. Administration of prolactin significantly increased the mortality of septic mice (81%). This was paralleled by a further decrease of splenocyte proliferation and an increased splenocyte apoptosis. In addition, administration of prolactin augmented the sepsis-induced inhibition of IL-2 release, attenuated the sepsis-induced inhibition of IFN-gamma release, and did not affect the release of IL-6. However, prolactin did not affect the sepsis-induced changes of circulating leukocyte subpopulations. CONCLUSIONS: We conclude that prolactin has profound immunomodulatory properties and that administration of prolactin in pharmacological doses is associated with a decreased survival and an inhibition of cellular immune functions in septic mice.  相似文献   
98.
The American Society of Colorectal Surgeons (ASCRS) recently endorsed low-molecular-weight heparin and low-dose heparin as primary prophylaxis for venous thromboembolism (VTE) in highest-risk patients. Our study evaluates the feasibility of sequential compression device (SCD) use for VTE prophylaxis in these patients. Computerized databases of discharge diagnoses from three hospitals were reviewed. All patients with colorectal cancer or inflammatory bowel disease during a 7-year period were identified. Those who underwent major abdominal surgery and received VTE prophylaxis exclusively with SCDs were selected for the study. Patients diagnosed with postoperative VTE were identified through review of the three databases and of patient records for 90 days after surgery. One thousand two hundred eighty-one patients classified as highest-risk under the published ASCRS parameters underwent major abdominal surgery and received SCDs perioperatively. The incidence of clinically detectable postoperative VTE was 0.78 per cent. There were trends toward lower incidence among patients with malignancy (0.53%) compared with inflammatory bowel disease (1.48%, P = 0.09), and those with abdominal compared to pelvic procedures (0.62% vs. 1.04%, P = 0.41). Prophylaxis for perioperative VTE solely with SCD is a viable option for patients classified as highest-risk under ASCRS parameters.  相似文献   
99.
Cellular mechanisms of ischemia-reperfusion injury   总被引:17,自引:0,他引:17  
As of yet, only a few strategies to prevent myocardial reperfusion injury have been tested clinically. In the first minutes of reperfusion, the myocardium can be damaged by contracture development, causing mechanical stiffness, tissue necrosis, and the "stone heart" phenomenon. Reperfusion-induced contracture can have two different causes, namely, Ca2+overload-induced contracture or rigor-type contracture. Ca2+ contracture results from rapid re-energization of contractile cells with a persistent Ca2+ overload. Strategies to prevent this type of injury are directed at cytosolic Ca2+ control or myofibrillar Ca2+ sensitivity. Rigor-contracture occurs when re-energization proceeds very slowly. It does not depend on Ca2+ overload. It may be prevented by strategies improving early mitochondrial reactivation  相似文献   
100.
Autoantibodies against CD38 (adenosine-5'-diphosphate[ADP]-ribosyl cyclase/cyclic ADP-ribose hydrolase) have been described in 10-12% of patients with type 2 diabetes. In human islets, anti-CD38 autoantibodies (CD38Abs) acutely stimulate insulin release (IR) and increase the cytosolic calcium concentration ([Ca(2+)](i)). Whether CD38Abs affect human islet cell function and survival upon prolonged in vitro exposure is not known. We cultured human islets for up to 7 days in the presence of sera from 10 patients with type 2 diabetes that had neither CD38Ab- nor [Ca(2+)](i)-mobilizing activity (-/-), sera from 6 patients with type 2 diabetes that was CD38Ab-positive and had [Ca(2+)](i)-mobilizing activity (+/+), or no sera (control). At baseline, +/+ sera caused a significant (P < 0.002) acute stimulation of IR (IR at 3.3 mmol/l glucose was 45 +/- 19, 84 +/- 24, and 34 +/- 12 micro U/ml in control, +/+, and -/- sera, respectively; the corresponding IR at 16.7 mmol/l glucose was 72 +/- 25, 204 +/- 56, and 80 +/- 32 micro U/ml). At 3 days, IR at 3.3 mmol/l glucose was 42 +/- 18, 27 +/- 11, and 43 +/- 24 micro U/ml (P = 0.0003) for control, +/+, and -/- sera, respectively, whereas at 16.7 mmol/l glucose, it was 95 +/- 76, 45 +/- 35, and 76 +/- 42 micro U/ml, respectively. After 7 days of exposure, the corresponding IR at 3.3 mmol/l glucose was 40 +/- 11, 28 +/- 12, and 35 +/- 15 micro U/ml, respectively, whereas at 16.7 mmol/l glucose it was 79 +/- 39, 39 +/- 17, and 62 +/- 39 micro U/ml. At both 3 and 7 days, IR still increased when switching from 3.3 to 16.7 mmol/l glucose (P < 0.0003), and incubation with +/+ sera induced a significant decrease in the insulin response (P < 0.002). At 7 days, the number of dead cells (as evaluated by an enzyme-linked immunosorbent assay technique) differed significantly between control (1.2 +/- 0.3 OD units) cells, islets exposed to -/- sera (1.4 +/- 0.1), and islets coincubated with +/+ sera (1.9 +/- 0.4, P < 0.01). We conclude that prolonged exposure of human islets to sera positive for the presence of CD38Abs with [Ca(2+)](i)-mobilizing activity impairs beta-cell function and viability in cultured human pancreatic islets.  相似文献   
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