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61.
To elucidate the role of catecholamines in attention deficit disorder, the authors conducted an open 8-week trial of L-tyrosine in 12 adults with attention deficit disorder, residual type. Eight showed marked to moderate clinical response in 2 weeks; at 6 weeks these eight developed tolerance, suggesting that L-tyrosine is not useful in attention deficit disorder, residual type. 相似文献
62.
A modified formulation of inhaled salbutamol and a new inhaler device were studied in a group of 11 moderate-to-severe asthmatic patients. Changes in airway calibre (FEV1, Vmax30) were measured before and after inhalation of the new formulation, and compared with changes following inhalation of conventional salbutamol. A standard Rotahaler was used as a reference for the new inhaler. The study was conducted as a two-part randomized, double-blind cross-over trial. We found a significantly greater bronchodilatation of the larger airways using the modified drug in the Rotahaler. The new inhaler did not show any superiority over the Rotahaler, contrary to expectations from in vitro work. A slightly shorter model may better reflect the in vitro results. The study has implications for inhalation therapy in general. 相似文献
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Bruce G. Haffty M.D. Peter L. Perrotta M.D. † Barbara Ward M.D. ‡ Meena Moran M.D. Malcolm Beinfield M.D. ‡ Charles McKhann M.D. ‡ Diana Fischer Ph.D. Darryl Carter M.D. † 《The breast journal》1997,3(1):7-14
Abstract: Between 1970 and 1990, 1,008 patients with early-stage breast cancer were treated by conservative surgery without axillary dissection followed by radiation therapy to the intact breast in the Department of Therapeutic Radiology at Yale-New Haven Hospital. The patient population, broken down by histologic subtype, was as follows: 761 patients presented with infiltrating ductal carcinoma, 70 patients with pure intraductal, 38 intraductal with focal invasion, 54 infiltrating lobular, 21 tubular, 17 medullary, 16 mucinous, and 29 with other various histologic subtypes. Patients were followed on a regular basis by the referring physicians and radiation oncologists. Diagnostic studies for distant metastases were performed as clinically indicated. Annual mammography was a routine component of the follow-up program. As of 3/96, with a median follow-up of 10.5 years, 83 patients developed an ipsilateral breast tumor recurrence, and 109 patients developed distant metastases resulting in an overall 10-year breast recurrence-free rate of 84%, and a 10-year distant metastasis-free rate of 78%. There were significant differences in clinical stage, pathological nodal involvement, and administration of systemic therapy between various histologic subtypes. As expected, those patients with histologies of low metastatic potential (such as intraductal, tubular, and mucinous) had significantly superior distant recurrence-free survival rates. With respect to breast relapse rates, there were no statistically significant differences in the 5- and 10-year breast recurrence-free rates between any of the histologic subtypes. Patients with intraductal carcinoma with or without focal invasion had similar breast relapse rates as those with other histologic subtypes. Patients with lobular carcinoma in situ as a histologic component also had a similar overall breast relapse-free recurrence rate. In conclusion, long-term follow-up of conservatively treated breast cancer patients demonstrates no significant differences in ipsilateral breast tumor recurrence rates between various histologic subtypes. There are no histologies which had a statistically significantly higher breast-relapse rate than infiltrating ductal carcinomas and therefore no primary histologic subtype represents a relative contraindication to breast conservation therapy. 相似文献
65.
An ex vivo model of hemodialysis was used to evaluate the effect of dialysis membranes on phagocytic cell function. Blood was withdrawn continuously from healthy, non-uremic donors, heparinized, and pumped, single pass, through membrane modules under conditions which simulated normal dialysis conditions. The membrane modules contained membranes of cellulose, DEAE-substituted cellulose, or polysulfone. Blood was obtained from the module outlets for determination of complement activation, phagocyte elastase release, zymosan-induced phagocyte chemiluminescence, and monocyte interleukin-1 production. Significantly less complement activation occurred with the polysulfone and DEAE-substituted cellulose membranes than with cellulose membranes. Normal monocyte interleukin-1 production was not stimulated by any of the membranes used. In contrast, the cellulosic, but not the polysulfone, membranes primed the oxidative burst of the phagocytes and caused them to release elastase. DEAE-substituted cellulose had a lesser effect on elastase release than did cellulose and elastase release correlated significantly with the degree of complement activation. However, the correlation between complement activation and priming of phagocyte oxidative burst was weak, suggesting that membranes affect phagocyte oxidative metabolism through more than one mechanism. We conclude that some dialysis membranes stimulate the bacteriacidal functions of normal phagocytic cells, in part through complement-dependent mechanisms. 相似文献
66.
Jonathan H. Waters MD Timothy B. Watson MD Michael G. Ward MD 《Journal of clinical anesthesia》1996,8(8):656-658
Multiple reports of cauda equina syndrome and transient radicular nerve root irritation have suggested that lidocaine spinal anesthesia may be responsible. In this case report, a patient with a preexisting diabetic neuropathy received a partial block following a tetracaine spinal, which was followed by a lidocaine spinal. Following block resolution, a new conus medullaris syndrome was diagnosed. Because of the close proximity of the cauda equina and the conus medullaris, differentiation between these syndromes can be difficult. The preexisting diabetic neuropathy may have predisposed this patient to neurologic injury. The choice of a different local anesthetic drug with less neurotoxic potential such as bupivacaine may have prevented this injury. 相似文献
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Margret S. Magid Wallace G. Campbell Jr MD Sutini Ngadiman Thomas A. Godwin MD Robert Ward 《Fetal and pediatric pathology》1997,17(2):303-314
We report a case of an infantile myofibromatosis with hemangiopericytoma-like features arising in the tongue of a 5-month-old female infant. Many authors now classify neoplasms as infantile myofibromatosis that were previously called infantile hemangiopericytoma. The ultrastructural features of our tumor illustrate its biphasic nature and provide a possible explanation for its histogenesis. Infantile myofibromatosis, including those diagnosed as infantile hemangiopericytomas, rarely arise in any intraoral location. Despite the generally good prognosis associated with these neoplasms, complete surgical excision is recommended to avoid recurrences. 相似文献