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51.
The plasma clotting factors used to treat hemophiliacs who have developed inhibitory antibodies have a shared history of limited clinical safety and utility. To improve on existing bypass factors, we have developed a reversibly acylated form of human plasma factor Xa capable of providing a time-dependent release of procoagulant activity. Factor Xa was treated with p-amidinophenyl p'-anisate to generate anisoyl Xa. The chemical modification of the protein involves acylation of the active site serine residue of factor Xa. Anisoyl Xa deacylated in a time, pH, and temperature-dependent manner. Active factor Xa generated on deacylation of anisoyl Xa exhibited amidolytic and prothrombinase complex activities in in vitro assays, the level being comparable to those of untreated factor Xa. When Anisoyl Xa was infused into rabbits, active factor Xa was generated on deacylation of the acylated enzyme, which shortened the activated partial thromboplastin time (APTT) in a dose-dependent manner. The duration of effect on rabbit APTT could be directly correlated to the level of human plasma factor Xa. Because anisoyl Xa bypasses the "tenase" complex that is compromised in hemophilia A and B and is unaffected by inhibitory antibodies, it has the potential to be used as an effective bypass therapy. 相似文献
52.
Intracranial neurenteric cysts: a report of two cases 总被引:7,自引:0,他引:7
Neurenteric or enterogenous cysts are rare, congenital, benign lesions of the central nervous system. Not more than 35 case reports of neurenteric cysts occurring in the cranial cavity have been documented. We describe two cases of intracranial neurenteric cysts. 相似文献
53.
Restless legs syndrome (RLS) is one of the commonest movement disorders affecting sleep and also daytime functioning. The prevalence may be 8%–10% of the white Caucasian population. The diagnosis is simple and is based on a well-validated clinical questionnaire, yet misdiagnosis is common and the condition remains underdiagnosed and consequently inappropriately treated, often causing great distress to the sufferers. In spite of robust evidence for effective treatment of RLS, patients may often be told to “put up with the symptoms” and suffer the consequence of years of poor sleep which may lead to major lifestyle changes. This review addresses the diagnostic issues, the differential diagnosis, and the evidence base for treatment of the common condition. 相似文献
54.
Chatzizacharias NA Vaidya A Sinha S Smith R Jones G Sharples E Friend PJ 《Clinical transplantation》2011,25(5):E509-E515
Chatzizacharias NA, Vaidya A, Sinha S, Smith R, Jones G, Sharples E, Friend PJ. Renal function in type 1 diabetics one year after successful pancreas transplantation.Clin Transplant 2011: 25: E509–E515. © 2011 John Wiley & Sons A/S. Abstract: The effect of pancreas transplantation on renal function remains a matter of debate. The purpose of this retrospective, single‐unit study is a preliminary analysis of renal function one yr after pancreas transplant (pancreas alone [PTA] or pancreas after kidney [PAK]). Fifty‐nine patients were included. Serum creatinine and estimated glomerular filtration rate (eGFR) levels were compared three, six, and 12 months post‐transplantation for the whole sample and separately for PTA and PAK and high (>45 mL/min/1.73 m2) and low (≤45 mL/min/1.73 m2) pre‐transplant eGFR subgroups. Overall, eGFR did not change significantly (p = 0.228) at the end of the first year post‐transplant, with patients of low initial eGFR presenting a more prominent trend toward stable or improved levels. In the PAK subgroup, eGFR was significantly improved (p = 0.035). High eGFR subgroup demonstrated no significant deterioration in renal function, while patients with low initial eGFR had significantly higher levels 3 (p = 0.012) and six months (p = 0.009) post‐transplant. Our study shows that renal function did not deteriorate significantly one yr after pancreas transplant (PTA or PAK), even in patients with substantial pre‐existing renal dysfunction. Evaluation at a wider scale and identification of risk factors for potential deterioration are challenges for future research. 相似文献
55.
Background:
Patellar dislocations are either due to superolateral contracture of the soft tissue or imbalance of the power between the vastus medialis (VM) and the vastus lateralis (VL). The imbalance of muscle power as an etiology of patellar dislocation has not been studied. Hence, we studied the recurrent, habitual and permanent dislocations of the patella with an electromyogram (EMG) of the vastus medialis, vastus lateralis, and pes anserinus, before and after realignment operations, to document the muscle imbalance and effectiveness of the realignment operation.Materials and Methods:
An electromyographic investigation was carried out on the vastus medialis and vastus lateralis in nine recurrent, 20 habitual, and 13 permanent dislocations of the patella, before and after their realignment operations. Pes anserinus transposition, which acted as a medial stabilizer of the patella, was also investigated with an EMG study, to understand its role on patellar stability at 0°, 30°, 60°, 90°, 120°, 150°, and full flexion of the knee. The age of the patients varied from nine to 30 (mean 15) years. There were 24 males and 18 females. Twenty-six patellar dislocations were on the right and 16 were on the left side.Results:
Electromyographic pictures reveal subnormal activity of the vastus medialis in all types of dislocations and similar activities of the vastus lateralis in permanent and habitual dislocations recorded pre operatively, which recovered to almost normal values postoperatively, at the mean one-year follow-up. Pes anserinus, which was used for medial stabilization of the patella after its realignment, maintained normal EMG activity before and after the operation.Conclusion:
This study is significant for understanding the imbalance of muscle activities in patients with an unstable patella, which can be rectified without recurrence after pes anserinus transposition. 相似文献56.
STUDY DESIGN: The first reported case of multiple intradural, extramedullary spinal metastasis from sinonasal undifferentiated carcinoma is presented. OBJECTIVES: To elucidate the mechanisms by which metastatic disease invades the spinal axis, and to discuss the possibility of spinal drop metastasis from head and neck tumors that invade the dura. SUMMARY OF BACKGROUND DATA: Sinonasal undifferentiated carcinoma is a rare yet aggressive neoplasm of the upper airways and anterior skull base. This neoplasm is known to invade the cranial vault and brain locally. However, it has not previously been reported to seed the cerebrospinal fluid or result in drop metastasis. Such drop metastasis may result in significant neurologic deficit if not diagnosed and treated in a timely manner. METHODS: This report is based on a single patient treated by a multidisciplinary team from the departments of neurosurgery, otolaryngology, and radiation oncology at the University of Southern California School of Medicine. RESULTS: This patient initially underwent resection and local radiation therapy for sinonasal undifferentiated carcinoma of the anterior skull base. At the time of surgery, the tumor was noted to violate the dura and arachnoid along the subfrontal plane. At 11/2 years after the initial treatment, a bandlike distribution developed at T2 as well as paresthesias and numbness below that level. Imaging of the spine showed an intradural, extramedullary tumor at T2 consistent with a schwannoma or meningioma. The patient underwent a laminectomy and tumor resection, which showed poorly differentiated sinonasal carcinoma. Local radiation therapy was administered, and the patient experienced complete recovery of neurologic function. Bilateral leg pain and weakness developed 14 months later. Magnetic resonance imaging of the spine showed a new intradural, extramedullary lesion at T12, remote from the first lesion. This second metastasis was managed with surgical resection and adjuvant radiation therapy. CONCLUSIONS: This is the first reported case of a sinonasal carcinoma leading to intradural extramedullary metastasis. The primary tumor likely seeded the cerebrospinal fluid, thus resulting in drop metastasis. Patients with sinonasal undifferentiated carcinoma that invades the dura should be monitored closely for evidence of metastasis before symptoms develop. 相似文献
57.
Lein M Jung K Elgeti U Petras T Stephan C Brux B Sinha P Winkelmann B Schnorr D Loening S 《European urology》2001,39(1):57-64
OBJECTIVE: To evaluate the diagnostic utility of free prostate specific antigen (fPSA), alpha-1- antichymotrypsin-bound PSA (PSA-ACT), complexed PSA (cPSA), and including their associated ratios to total PSA (tPSA) in serum for discrimination between prostate cancer (PCa) and benign prostatic hyperplasia (BPH). METHODS: A total of 166 white men (age: 65-88 years) with a tPSA between 2 and 20 microg/l were retrospectively analysed. Serum concentrations of tPSA, fPSA, PSA-ACT and cPSA were measured in 118 untreated PCa patients and 48 patients with BPH. The tPSA and cPSA concentrations were measured with the Bayer Immuno 1 system (Bayer Diagnostics, Tarrytown, USA). The Elecsys system 2010 (Roche Diagnostics, Mannheim, Germany) was used for determination of tPSA and fPSA. The PSA-ACT assay is a newly, developed prototype assay on the ES system (Roche Diagnostics, Mannheim, Germany). RESULTS: For statistical analysis only patients with tPSA between 2 and 20 microg/l were enrolled. The median concentrations of tPSA (Bayer: PCa 7.36 microg/l, BPH 4.03 microg/l; Roche: PCa 7.75, BPH 4.13), PSA-ACT (PCa 6.98, BPH 3.18) and cPSA (PCa 6.46, BPH 3.20) were significantly different. The median ratios of fPSA/tPSA (PCa 12.8 vs. BPH 22.4%), PSA-ACT/tPSA (PCa 89.8 vs. BPH 76.1%) and cPSA/tPSA (PCa 90.5 vs. BPH 81.7%) were significantly different between PCa and BPH patients. Using the areas under the curves, receiver operating characteristics analysis (tPSA: 2-20 microg/l) for discrimination between PCa and BPH showed that the ratios fPSA/tPSA (area under the curve: 0.77), PSA-ACT/tPSA (0.72) and cPSA/tPSA (0.78) were significantly different from tPSA (Bayer: 0.53; Roche: 0.55). PSA-ACT (0.64) and cPSA (0.59) alone were not significantly different from tPSA. The calculated ratios fPSA/tPSA, PSA-ACT/tPSA and cPSA/tPSA were not significantly different. CONCLUSION: The determination of PSA-ACT or cPSA and the associated ratios do not improve the diagnostic impact to discriminate between PCa and BPH compared to fPSA/tPSA ratio. The ratios PSA-ACT/tPSA or cPSA/tPSA can be considered to be alternative tools of fPSA/tPSA. 相似文献
58.
Mary Courtney Moore Marta S. Smith Vikram P. Sinha John M. Beals M. Dodson Michael Scott J. Jacober Alan D. Cherrington 《Diabetes》2014,63(2):494-504
The impact of the novel basal insulin LY2605541 (LY) on hepatic and nonhepatic glucose uptake (non-HGU) was evaluated. Conscious dogs underwent euglycemic clamps with tracer and hepatic balance measurements. Clamp period infusions were peripheral venous regular insulin (0.1 nmol ⋅ kg−1 ⋅ h−1 [control], n = 6) or LY (bolus [nmol/kg], continuous [nmol ⋅ kg−1 ⋅ h−1]: 0.5, 0.5 [n = 6]; 0.375, 0.375 [n = 5]; 0.25, 0.25 [n = 4]), somatostatin, and glucose, as well as intraportal glucagon (basal). During the clamp, the dogs switched from net hepatic glucose output to uptake (rates reached 2.1 ± 1.2, 0.9 ± 2.1, 8.6 ± 2.3, and 6.0 ± 1.1 µmol ⋅ kg−1 ⋅ min−1 within 5 h in control, LY0.25, LY0.375, and LY0.5, respectively). Non-HGU in LY increased less than in control; the ratio of change from basal in non-HGU to change in net hepatic glucose balance, calculated when glucose infusion rates (GIRs) were ~20 µmol ⋅ kg-1 ⋅ min−1 in all groups, was higher in control (1.17 ± 0.38) versus LY0.25 (0.39 ± 0.33), LY0.375 (−0.01 ± 0.13), and LY0.5 (−0.09 ± 0.07). Likewise, the change from baseline in glucose Rd-to-Ra ratio was greatest in control (1.4 ± 0.3 vs. 0.6 ± 0.4, 0.5 ± 0.2, and 0.6 ± 0.2 in LY0.25, LY0.375, and LY0.5, respectively). In contrast to exogenously administered human insulin, LY demonstrated preferential hepatic effects, similar to endogenously secreted insulin. Therefore, the analog might reduce complications associated with current insulin therapy. 相似文献
59.
Objectives
Nephrolithiasis has been reported in 20-28% of patients, of whom 50% are symptomatic for stone disease and 20% require definite urologic intervention. The management of nephrolithiasis includes oral alkali dissolution therapy, extracorporeal shock wave lithotripsy and surgical treatment. In such patients, percutaneous nephrolithotomy (PNL) as a method of stone treatment has been reported in few cases with limited experience. The aim of this study is to present our experience of PNL in autosomal dominant polycystic kidney disease (ADPKD) and assessing the outcome results.Material and Methods
From 2002 to 2011, 22 patients (26 renal units) suffering from ADPKD with stone were managed by PNL. Demographic characteristics, operative parameters and postoperative complications were recorded and analysed.Result
The overall success rate of PNL was 82.1% and PNL with extracorporeal shock wave lithotripsy for clinically significant residual fragments was 92.85% respectively. The hematuria required blood transfusion (n = 9), postoperative fever due to cyst infection (n = 4) and paralytic ileus (n = 3) were recorded.Conclusion
The PNL in ADPKD PNL is safe and effective but have more postoperative complications such as bleeding requiring transfusions, fever due to cyst infection and paralytic ileus.Key Words: Percutaneous nephrolithotomy, Nephrolithiasis, Autosomal dominant polycystic kidney disease 相似文献60.
The hemolytic plaque assay technique can be used to detect specific hormone release from single pituitary cells. Using antisera raised against murine GH or rat PRL, we have enumerated the active lactotropes and somatotropes from male and female rat pituitary glands. These studies reveal sex-related differences in the number of cells exporting GH and PRL among anterior pituitary cells in culture. In the presence of human GH-releasing factor (hGRF), the mean percentage of GH cells was 53% in males and 30% in females (P less than 0.005). The mean percentage of PRL cells was 15% in males and 39% in females (P less than 0.008). These values were not significantly altered when hGRF was omitted. The sum of GH and PRL cells identified in separate plaque assays significantly exceeds the number obtained when GH and PRL cells were determined concurrently with a simultaneous plaque assay for both hormones. This difference is dependent on the presence of hGRF, since there was no difference when hGRF was omitted. These data identify the mammosomatotrope in numbers lower than previous reports. By this approach, the mammosomatotrope subpopulation numbers about 5% of all cells in culture. In summary, we demonstrate a sex-related difference in the number of cells exporting GH or PRL among pituitary cells in culture. This difference corresponds with and may underly sex-related differences in the responsiveness of GH and PRL secretion from the pituitary gland. Furthermore, a minor subpopulation of normal pituitary cells appears capable of simultaneous secretion of both GH and PRL. 相似文献