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101.
Fast CT-PRESS-based spiral chemical shift imaging at 3 Tesla.   总被引:2,自引:0,他引:2  
A new sequence is presented that combines constant-time point-resolved spectroscopy (CT-PRESS) with fast spiral chemical shift imaging. It allows the acquisition of multivoxel spectra without line splitting with a minimum total measurement time of less than 5 min for a field of view of 24 cm and a nominal 1.5x1.5-cm2 in-plane resolution. Measurements were performed with 17 CS encoding steps in t1 (Deltat1=12.8 ms) and an average echo time of 151 ms, which was determined by simulating the CT-PRESS experiment for the spin systems of glutamate (Glu) and myo-inositol (mI). Signals from N-acetyl-aspartate, total creatine, choline-containing compounds (Cho), Glu, and mI were detected in a healthy volunteer with no or only minor baseline distortions within 14 min on a 3 T MR scanner.  相似文献   
102.
Costimulatory signals regulate T-cell activation. To investigate the role of costimulation in autoimmunity and transplantation, we studied the BB rat model of type 1 diabetes. Diabetes-prone BB (BBDP) rats spontaneously develop disease when 55–120 days of age. We observed that two anti-CD28 monoclonal antibodies (mAb) with different functional activities completely prevented diabetes in BBDP rats. Anti-CD154 mAb delayed diabetes, whereas treatment with CTLA4-Ig or anti-CD80 mAb accelerated disease. Anti-CD86 or anti-CD134L mAbs had no effect. Diabetes resistant BB (BBDR) rats are disease-free, but >95% of them develop diabetes after treatment with polyinosinic-polycytidylic acid and an mAb that depletes Treg cells. In the induced BBDR model, anti-CD154 mAb delayed onset of diabetes, whereas CTLA4-Ig, anti-CD134L or either of the anti-CD28 mAbs had little or no effect. In contrast, blockade of the CD134-CD134L pathway was highly effective for preventing autoimmune recurrence against syngeneic islet grafts in diabetic BBDR hosts. Blockade of the CD40-CD154 pathway was also effective, but less so. These data suggest that the effectiveness of costimulation blockade in the treatment of type 1 diabetes is dependent on both the costimulatory pathway targeted and the mechanism of induction, stage, intensity and duration of the pathogenic process.  相似文献   
103.
Although surgical lung resection could improve prognosis in some patients with multidrug-resistant tuberculosis (MDR-TB), there are no reports on the optimal candidates for this surgery. The aim of the present study was to elucidate the prognostic factors for surgery in patients with MDR-TB. Patients who underwent lung resection for the treatment of MDR-TB between March 1993 and December 2004 were included in the present study. Treatment failure was defined as greater than or equal to two of the five cultures recorded in the final 12 months of treatment being positive, any one of the final three cultures being positive, or the patient having died during treatment. The variables that affected treatment outcomes were identified through univariate and multivariate logistic regression analysis. In total, 79 patients with MDR-TB were included in the present study. The treatment outcomes of 22 (27.8%) patients were classified as failure. A body mass index <18.5 kg x m(-2), primary resistance, resistance to ofloxacin and the presence of a cavitary lesion beyond the range of the surgical resection were associated with treatment failure. Low body mass index, primary resistance, resistance to ofloxacin and cavitary lesions beyond the range of resection are possible poor prognostic factors for surgical lung resection in multidrug-resistant tuberculosis patients.  相似文献   
104.
Generally, a computed tomography scan is conducted for the diagnosis of stroke in the emergency department, because these scans are easier and faster in the detection of stroke. If there are no signs of hemorrhage on computed tomography scan, an ischemic stroke is diagnosed and treated accordingly. A magnetic resonance imaging scan may be taken in order to verify ischemic stroke. This process may lead to improper treatment and is time consuming. To address this situation, case studies are presented in which magnetic resonance imaging diffusion-weighted imaging and gradient recalled echo were performed to detect hemorrhagic and ischemic stroke and particularly, subarachnoid hemorrhage, which is undetectable with a computed tomography scan.  相似文献   
105.
106.
BACKGROUND: We hypothesized that the incidence of hypotension during total knee replacement (TKR) surgery is lower in patients given combined spinal-epidural (CSE) anesthesia vs those receiving epidural anesthesia alone. METHODS: In a prospective study, 80 American Society of Anesthesiologists I-II patients (aged 40-80 yr), undergoing elective TKR surgery were randomly assigned to either CSE anesthesia (CSE, n = 40) or epidural anesthesia alone (Epidural, n = 40). Hemodynamic measurements included oscillometric mean arterial blood pressure (MAP), heart rate (HR), and cardiac index (CI) as determined by thoracic bioimpedance; systemic vascular resistance (SVR) was calculated. Our primary endpoint (outcome) was the number of hypotension episodes (defined as MAP < 70 mmHg). RESULTS: Using univariate analysis, we found no differences between the groups in regards to MAP, HR, CI, or SVR during the perioperative period. The incidence of hypotension was similar in both groups (two patients in each group), as was the incidence of bradycardia (12 patients in CSE, 7 in Epidural; P = 0.2). There were no differences between groups in other hemodynamic measurements including CI and calculated SVR. Analgesia supplementation with fentanyl was more frequently required in the Epidural group (20 vs 6 patients - P = 0.03). CONCLUSION: Combined spinal-epidural anesthesia and epidural anesthesia alone during TKR surgery are associated with the same incidence of hypotension with statistically and clinically similar hemodynamic responses.  相似文献   
107.
Twenty-five women receiving sedation for outpatient hysteroscopic polypectomy were injected with 0.25% bupivacaine 10 mL (paracervical group) and another 25 received the same volume of saline (control group) at the cervical fornix. Both groups were given target-controlled propofol sedation during the procedure. More propofol (mg/min) was needed for adequate anesthesia in the control group compared to the paracervical group (6.5 versus 4.6). In addition, the postoperative pain scores were lower in the paracervical group than in the control group. Hemodynamic changes and postoperative side effects were similar in the two groups. This prospective, randomized, double-blind, placebo-controlled study confirmed the effective use of paracervical blocks. This approach has the effect of reducing the amount of intraoperative propofol and decreasing postoperative pain in outpatient hysteroscopic surgery.  相似文献   
108.
BACKGROUND CONTEXT: Substantial variation exists regarding the use of sedation before interventional spine techniques. Patient preference should play an important role in decision making regarding the need for sedation. However, little is known about patients' anxiety levels before spinal injections and their perceptions about the necessity of sedation. PURPOSE: To determine patient perception for need for sedation before epidural steroid injections and zygapophyseal joint injections. STUDY DESIGN/SETTING: Survey of consecutive spinal injection patients in an outpatient spine center. PATIENT SAMPLE: 500 consecutive lumbar, thoracic, and cervical patients receiving spinal injections. OUTCOME MEASURES: A 12-item questionnaire assessing patients' perceived anxiety before to a spinal injection. METHODS: Subjects were given the questionnaire after their spinal injection. Percentages requesting sedation for a first and potential second procedure were assessed. Additionally, anxiety level and pain rating, location of injection, age, sex, and other medication use were analyzed to determine the effect on the request for sedation. RESULTS: 17% of patients questioned requested sedation before an injection, and 28% would request sedation if they were to have a second injection. CONCLUSIONS: Routine sedation before diagnostic and therapeutic injections is not necessary as the majority of patients would not request sedation before the procedure when given the option. However, in some patients sedation is indicated, and all patients would benefit from educational material on sedation before the injection.  相似文献   
109.
Muscarinic receptors play key roles in the control of gastrointestinal smooth muscle activity. However, specific physiological functions of each subtype remain to be determined. Single cell RT-PCR experiments showed that all five subtypes of muscarinic receptors were present in circular smooth muscle cells of the guinea-pig gastric antrum. Nonselective cation channels (NSCC) activated by ACh or CCh are coupled to pertussis toxin (PTX)-sensitive Go protein through m4 subtype as well as m2 and m3 subtypes in guinea-pig stomach. CCh-activated currents (I(CCh)), especially the steady-state I-V relationship of I(CCh) showed a chracteristic U-shaped curve; reversal potential of around 0 mV and inward rectification at around +15 mV and a negative slope conductance at negative potential range. Under physiological conditions, the measured single channel conductance of NSCC was approximately 25 pS. The single channel conductance was modulated by external monovalent and divalent cations including Na+, Cs+, Li+, and Ca2+ through changing both the open probability and unitary conductance. Through the NSCC, Ca2+ can move into the cell from extracellular solution as well as Na+. Calculated fractional Ca2+ current of I(CCh) (f(Ca)) was around 1% at the 2 mM [Ca2+]o and at the 4 mM [Ca2+]o, f(Ca) was 2.3%. Quinidine blocked I(CCh) potently in a reversible manner; IC50 was 0.25 microM. There were two kinds of I(CCh) modulations through Ca(2+)-dependent pathways in guinea-pig gastric smooth muscle cells; 1) Facilitation of I(CCh) via Ca2+/CaM-dependent MLCK pathway, 2) Desensitization of I(CCh) via Ca(2+)-dependent PKC pathway. In the mouse stomach, all seven types of TRPC mRNA were detected with RT-PCR. On the basis of electrophysiological, pharmacological, and molecular biological experiments, we reported the mTRPC5 as a candidate for the NSCC activated by muscarinic stimulation in mouse stomach.  相似文献   
110.
This article describes a modified suture technique designed for the vertical repair of the anterior horn of the meniscus after arthroscopic decompression of a large meniscal cyst. This procedure comprises of three steps: first, the meniscus was pierced vertically using a suture hook and a No. 0 PDS suture. Second, both ends of the No. 0 PDS on the femoral and tibial surfaces of the meniscus were pulled to the outside of the joint capsule using a spinal needle preloaded with suture material. Finally, a skin incision was made adjacent to the suture materials, and both ends were tied. We recommend this technique not only for the vertical repair of the anterior horn of the meniscus after decompression of large meniscal cyst, but also to repair a longitudinal tear of the meniscus.  相似文献   
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