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排序方式: 共有2435条查询结果,搜索用时 171 毫秒
961.
962.
WT Carpenter RW Buchanan B Kirkpatrick AF Breier 《Canadian Metallurgical Quarterly》1999,156(2):299-303
OBJECTIVE: Therapeutic intervention at the earliest phase of symptom exacerbation in schizophrenia is an important clinical need, but specific pharmacotherapeutic interventions for this phase of illness have not been established. This study examined diazepam efficacy for this phase of treatment. METHOD: A double-blind, randomized clinical trial with 53 schizophrenic patients compared diazepam with placebo (with fluphenazine treatment for a comparison group). Treatment was initiated at the earliest signs of exacerbation, and symptom progression was the dependent measure used to evaluate efficacy. RESULTS: Diazepam was statistically superior to placebo in preventing symptom progression and was comparable to fluphenazine. CONCLUSIONS: Efficacy data support the use of diazepam in treating prodromal and early warning signs of symptom exacerbation in schizophrenia. This therapeutic strategy may be especially important for patients who refuse antipsychotic drugs or as a supplemental approach in a treatment plan that emphasizes low-dose antipsychotic therapy. 相似文献
963.
JO Brubaker Q Li AO Tzianabos DL Kasper RW Finberg 《Canadian Metallurgical Quarterly》1999,162(4):2235-2242
Bacteroides fragilis, a Gram-negative colonic bacterium, induces the formation of abscesses associated with intra-abdominal sepsis in humans. The singular ability of this organism to modulate abscess formation in experimental rodent models resides in the structurally distinct and ionically charged capsular polysaccharides A (PS A) and B (PS B). The regulation of abscess formation in animals is dependent on T lymphocytes. However, the manner in which PS A interacts with T cells remains unknown. We therefore tested the T cell stimulatory capacity of purified PS A on mouse and rat lymphocytes in cellular proliferation assays and found that the PS A molecule possesses mitogenic characteristics distinguishable from those of the polyclonal B cell activator LPS, the T cell mitogen Con A, and staphylococcal enterotoxin A superantigen. Further, PS A stimulated proliferation of normal mouse and rat lymphocytes differentially. Mouse B cells responded to PS A in a fashion that did not require exogenous APC function, while rat T lymphocyte responses to PS A required APC function derived from autologous or xenogenic feeder cells. Cellular depletion experiments showed that the CD4+ subset of rat spleen cells was the primary responder cell type to PS A in vitro. The differential stimulatory effects of PS A on mouse and rat lymphocytes may reflect its ability to stimulate different lymphocyte subsets in vivo through the activities of receptor/counter-receptor pairs present on responder lymphocytes and cognate APC. 相似文献
964.
EJ Geigel RW Hyde IB Perillo A Torres PT Perkins AP Pietropaoli LM Frasier MW Frampton MJ Utell 《Canadian Metallurgical Quarterly》1999,86(1):211-221
This report describes methods for measuring nitric oxide production by the lungs' lower alveolar airways (VNO), defined as those alveoli and bronchioles well perfused by the pulmonary circulation. Breath holding or vigorous rebreathing for 15-20 s minimizes removal of NO from the lower airways and results in a constant partial pressure of NO in the lower airways (PL). Then the amount of NO diffusing into the perfusing blood will be the pulmonary diffusing capacity for NO (DNO) multiplied by PL and by mass balance equals VNO, or VNO = DNO(PL). To measure PL, 10 normal subjects breath held for 20 s followed by exhalation at a constant flow rate of 0.83 +/- 0.14 (SD) l/s or rebreathed at 59 +/- 15 l/min for 20 s while NO was continuously measured at the mouth. DNO was estimated to equal five times the single-breath carbon monoxide diffusing capacity. By using breath holding, PL equaled 2.9 +/- 0.8 mmHg x 10(-6) and VNO equaled 0.39 +/- 0.12 microl/min. During rebreathing PL equaled 2.3 +/- 0.6 mmHg x 10(-6) and VNO equaled 0.29 +/- 0.11 microl/min. Measurements of NO at the mouth during rapid, constant exhalation after breath holding for 20 s or during rebreathing provide reproducible methods for measuring VNO in humans. 相似文献
965.
Medicare coverage falls short of its original mandate of access to modern medicine and protection against the high costs of medical care. These shortfalls destabilize both health outcomes and the economic viability of older adults and their families. Our proposed revisions would promote, rather than discourage, optimal care for beneficiaries. By replacing incentives for fragmented, episodic care with an orientation toward functional status, care management, and integration with long-term care, we can make an invaluable investment in a successfully aging society. 相似文献
966.
JJ Weis BA McCracken Y Ma D Fairbairn RJ Roper TB Morrison JH Weis JF Zachary RW Doerge C Teuscher 《Canadian Metallurgical Quarterly》1999,162(2):948-956
A spectrum of disease severity has been observed in patients with Lyme disease, with approximately 60% of untreated individuals developing arthritis. The murine model of Lyme disease has provided strong evidence that the genetic composition of the host influences the severity of arthritis following infection with Borrelia burgdorferi: infected C3H mice develop severe arthritis while infected C57BL/6N mice develop mild arthritis. Regions of the mouse genome controlling arthritis severity and humoral responses during B. burgdorferi infection were identified in the F2 intercross generation of C3H/HeNCr and C57BL/6NCr mice. Rear ankle swelling measurements identified quantitative trait loci (QTL) on chromosomes 4 and 5, while histopathological scoring identified QTL on a unique region of chromosome 5 and on chromosome 11. The identification of QTL unique for ankle swelling or histopathological severity suggests that processes under distinct genetic control are responsible for these two manifestations of Lyme arthritis. Additional QTL that control the levels of circulating Igs induced by B. burgdorferi infection were identified on chromosomes 6, 9, 11, 12, and 17. Interestingly, the magnitude of the humoral response was not correlated with the severity of arthritis in infected F2 mice. This work defines several genetic loci that regulate either the severity of arthritis or the magnitude of humoral responses to B. burgdorferi infection in mice, with implications toward understanding the host-pathogen interactions involved in disease development. 相似文献
967.
AF Rosenbaum AJ McGoron RW Millard M Gabel D Biniakiewicz RA Walsh MC Gerson 《Canadian Metallurgical Quarterly》1999,34(2):91-98
RATIONALE AND OBJECTIVES: Direct comparison of myocardial perfusion tracers has been made difficult by variability in experimental models, and by a virtual absence of data comparing tracer uptake to myocardial blood flow under conditions of increased myocardial oxygen consumption, similar to what occurs with dynamic exercise. METHODS: Tracer uptake versus myocardial blood flow was evaluated for thallium-201 (201TI) and six technetium-99m (99mTc) myocardial-imaging agents in 24 open-chest canines with an occluded left-anterior descending coronary artery during dobutamine infusion. Data were fitted to the exponential model y = ax(1 - exp[-PSc/x]), where y is the tissue tracer/g normalized to normal (activity at 1 mL/minute/g) and x is the blood flow measured by the radioactive microsphere method. RESULTS: With dobutamine, myocardial tracer uptake was linear across a wide range of ischemic and hyperemic flows for each tracer. Based on the permeability surface area product, 201TI and 99mTc Q3 provided the best tracer estimate of myocardial blood flow (5.30+/-0.86 mL/minute/g, r = 0.91; 5.46+/-0.58 mL/minute/g, r = 0.94, respectively). Correlation coefficient (r) values for other tracers studied were 99mTc Q4 (r =0.93), 99mTc Q12 (r = 0.93), 99mTc sestamibi (r = 0.90), 99mTc tetrofosmin (r = 0.96), and 99mTc-N-Noet (r = 0.82). CONCLUSIONS: Of the 99mTc tracers examined under conditions of dobutamine-altered myocardial contractility, the myocardial uptake properties of 99mTc Q3 were most similar to those of 201TI. 相似文献
968.
TH Mallory AV Lombardi RA Fada SM Herrington RW Eberle 《Canadian Metallurgical Quarterly》1999,(358):166-172
The three basic surgical approaches used most commonly in total hip arthroplasty are transtrochanteric, posterior, and anterolateral. Complications related to each of these surgical approaches have been reported including dislocation, trochanteric nonunion, heterotopic ossification, neurovascular damage, postoperative limp, and implant malalignment. The anterolateral abductor split approach previously has been reported to allow ease of access into the hip joint, optimum joint visualization, protection of neurovascular structures of the hip, and predictable results for postoperative hip function restoration. Reviewing a large consecutive series of primary total hip arthroplasty cases (1518), the authors report an overall dislocation rate less than 1% (12:1518; 0.79%). Stratified by preoperative diagnosis, patients undergoing total hip arthroplasty after trauma, or presenting with congenital dysplastic hip are at the highest risk for postoperative dislocation. Primary total hip arthroplasty using the anterolateral, abductor split approach can minimize the rate of postoperative dislocation in the prevailing preoperative diagnostic categories. 相似文献
969.
970.
A major problem with treating patients with cancer by traditional chemotherapeutic regimes is that their tumors often develop a multidrug resistant (MDR) phenotype and subsequently become insensitive to a range of different chemotoxic drugs. One cause of MDR is overexpression of the drug-effluxing protein, P-glycoprotein. It is now apparent that P-glycoprotein may also possess a more generic antiapoptotic function that protects P-glycoprotein-expressing cancer cells and normal cells from cell death. Herein we show that cells induced to express P-glycoprotein either by drug selection or by retroviral gene transduction with MDR1 cDNA are resistant to cell death induced by a wide range of death stimuli, such as FasL, tumor necrosis factor (TNF), and ultraviolet (UV) irradiation, that activate the caspase apoptotic cascade.However, P-glycoprotein-expressing cells were not resistant to caspase-independent cell death mediated by pore-forming proteins and granzyme B.MDR P-glycoprotein-expressing cells were made sensitive to caspase-dependent apoptosis by the addition of anti-P-glycoprotein antibodies or verapamil, a pharmacological inhibitor of P-glycoprotein function. Clonogenic assays showed that P-glycoprotein confers long-term resistance to caspase-dependent apoptotic stimuli but not to caspase-independent cell death stimuli. This study has confirmed a potential novel physiological function for P-glycoprotein and it now remains to dissect the molecular mechanisms involved in the inhibition of capsase-dependent cell death by P-glycoprotein. 相似文献