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41.
Parathyroid carcinoma (PC) is a rare malignancy that poses a diagnostic challenge on histologic examination. We analyzed various clinicopathologic features of PC. Pathology reports and slides were reviewed to evaluate the diagnostic histopathologic features of archived cases of PC from the years of 2004–2018. The study cohort comprised twenty cases of PC. The median age was 49 years (range 21–73 years) with equal gender distribution (M:F = 1:1). Most patients presented with symptoms of hypercalcemia (n = 7, 54%). Serum calcium and serum parathyroid hormone were elevated in all but one patient. The right inferior parathyroid was commonly involved (n = 8/14, 57%). The mean tumor size was 2.4 cm (range 0.8–3.5 cm). On frozen section examination, PC was diagnosed in 8 out of 9 cases. Vascular (n = 19/20, 95%) and soft tissue invasion (n = 10/20, 50%) were the most common characteristic histologic findings. Capsular invasion was identified in all cases. Perineural invasion or metastasis at presentation was absent in all cases. Other histological features noted were intratumoral fibrous bands (70%), nodular growth pattern (70%), moderate nuclear atypia (30%), prominent nucleoli (20%), and necrosis (20%). Regional lymph nodes were negative for metastatic disease in all cases (n = 10). Eight out of 16 patients received adjuvant radiotherapy. Follow-up was available in 16 cases (median 21.5 months). Two patients died of disease. Vascular and soft tissue invasion are the most common diagnostic histologic features of PC. Capsular invasion is important to distinguish PC from its benign counterparts. Intraoperative frozen section examination can be used for accurate diagnosis and surgical management.  相似文献   
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Employment of geriatric nurse practitioners (GNPs) is one strategy to improve nursing home care. The effects of GNPs on costs and profitability of nursing homes and on costs of patient medical service use outside the nursing home are examined. Employment of GNPs does not adversely affect nursing home costs or significantly affect profits. There is some evidence of cost savings in medical service use for newly admitted patients but no evidence of savings for continuing residents. GNPs reduce the use of hospital services for both groups, and the reduction is statistically significant for newly admitted patients.  相似文献   
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This review first describes the preclinical findings with sertindole, a novel phenyl indole derivative antipsychotic agent. Second, a summary is provided of the major clinical trials conducted to date. Based on these findings, sertindole appears to be an effective antipsychotic agent for the treatment of positive and negative symptoms of schizophrenia, with efficacy that is clearly superior to placebo. Sertindole is as effective as haloperidol, however, is much better tolerated with significantly fewer adverse neurologic effects across a wide dosage range of both drugs. Sertindole is associated with a significant mean prolongation of the QT and QTc intervals of 3 - 6% from baseline in placebo-controlled studies. This potential adverse effect should be taken into account when treating specific patients with known risk factors for ventricular arrhythmias. Sertindole should prove to be a very useful addition to the therapeutic options available for the treatment of psychotic disorders.  相似文献   
46.
In this prospective, randomized study, 23 patients having spinal anaesthesia for transurethral prostatectomy (TURP) were evaluated for the adequacy of their block using a visual analog pain score (V4 PS). Each patient with a “standard”(≥T10) block level (n = 5) or “intermediate” (L1 or T12) block level (n = 5) found the block adequate. Sixty-two percent (8/13) of patients with a “low”-L3) block level found their block adequate. The VAPS was assessed every five minutes or whenever pain abruptly increased during TURP; an “inadequate block” was defined as a V4 PS ≥ 5 /10 during prostatic resection. Intravesical pressure was monitored and kept <15 mmHg to distinguish between pain from bladder distension and from prostatic resection. “Low” block patients (LBP) who found their block inadequate (n = 5) received supplemental intrathecal local anaesthetic given through a spinal catheter. The subsequent L1 block level was adequate for TURP. In LBP, who found their block adequate (n = 8), a higher (P < 0.01) VAPS was observed than in patients with a “standard” block level. However, a smaller (P < 0.05) maximum percent decrease in diastolic blood pressure was found in LBPs, than in “intermediate” or “standard” block patients. It is concluded that a spinal block ≥L1) is adequate during TURP when bladder pressure is monitored and kept low. Mid-lumbar block levels should be reserved for patients in whom the benefit of minimizing haemodynamic changes outweighs the risk of a “less complete” anaesthetic.  相似文献   
47.
A practice analysis, in which an appropriate sample of professionals is asked to describe what they do in their practices, is considered an essential part of the content-related validity evidence for licensure and certification tests. This article examines the precision of estimates of the mean frequencies for categories of activities in an activity inventory administered on two occasions about 6 weeks apart. In particular, it explores the variability in estimates of the mean frequencies for categories due to the sampling of respondents, activity statements, and occasions. The results suggest that samples of 200 respondents, about 10 to 20 activity statements per category, and one occasion are adequate for estimating the mean frequency for each category.  相似文献   
48.
Ras proteins (H-, K-, and N-p21ras) play critical roles in the control of normal and neoplastic cell growth. To date, however, little is known about the role of p21ras in regulating mitogen-induced smooth muscle and, specifically, human airway smooth-muscle (HASM) cell growth. We postulate that p21ras is a critical signaling event regulating mitogen-induced HASM cell proliferation. Growth-arrested, confluent HASM cells were treated for 1 h with 10 ng/ml epidermal growth factor (EGF), 1 U/ml thrombin, or 5 microM bradykinin, then cell lysates were immunoprecipitated using anti-p21ras antibody. Immunoblot analysis using a pan p21ras antibody, which recognizes H-, K-, and N-p21ras, found no significant difference in p21ras expression in HASM after stimulation with either agent, as compared with control. In parallel experiments, we characterized that HASM cells express K- and N-p21ras, but not H-p21ras. Further, there was no difference between the levels of each p21ras isoform after stimulation with any of the agonists. The time course of p21ras activation, however, was markedly different among agonists. EGF rapidly activated p21ras within 30 s and was sustained for up to 30 min. Although thrombin also induced a rapid rise in p21ras activity after 2.5 min, the activation was transient. In contrast, bradykinin, which is nonmitogenic for HASM cells, did not activate p21ras. Using single-cell microinjection, the role of p21ras activation in modulating mitogen-induced HASM DNA synthesis was determined by 5-bromo-2'-deoxyuridine (BrdU) incorporation and anti-BrdU immunofluorescent staining. Thrombin- and EGF-induced DNA synthesis in cells microinjected with Y13-259, a neutralizing p21ras antibody, was significantly inhibited as compared with those microinjected with isotype-matched rat immunoglobulin G(1) or a vehicle control. These data suggest that activation of p21ras appears to be necessary for EGF and thrombin-induced HASM cell proliferation and that activation of K- and N-p21ras, but not H-p21ras, mediates smooth-muscle cell growth.  相似文献   
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50.
Sixty-six patients had surgery for an intramedullary nerve sheath tumour under the care of one surgical team in a 16-year period. Surgery concentrated on radical intra- and extradural excision combined if necessary with vertebral column reconstruction. Ninety procedures were used in 35 males and 30 females with an age range 12-81 years. Forty-five per cent were located in the cervical, 26% in the thoracic and 29% in the lumbosacral region. Eighteen patients had NF1 and two patients NF2. Sixty-five per cent were schwannomas, 27% were mixed histology and 6% malignant. In terms of functional outcome, 37 patients improved by one or more Frankel grades, three deteriorated by one Frankel grade and no one who presented with symptoms alone deteriorated. There were no operative deaths; no instrumentation failures and five patients developed a CSF leak.  相似文献   
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