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131.
132.
Derivatives of apomorphine and of N-n-propylnorapomorphine were prepared to obtain modified pharmacological activity and enhanced chemical stability. Mouse profile and dog emesis screens were performed, and the activity of various N-substituted derivatives and their esters was evaluated and compared to the parent compounds. The N-n-propyl diacetate derivative and N-methyl and N-n-propyl ascorbate salts were remarkably stable to air: apomorphine etherate was no more stable than the free base. The dimers, the major products formed during the acid-catalyzed rearrangement of morphines to apomorphines, were all potent emetics. Additionally, two showed a significant antagonism to morphine in mice and dogs.  相似文献   
133.
In evaluating the pregnant patient with abdominal pain, the physician is presented with a wide range of diagnostic possibilities, including disorders that can occur in nonpregnant individuals and disorders that are unique to pregnancy. The development of modern laboratory testing methods and diagnostic imaging techniques has led to a decline in the morbidity and mortality from many of these disorders. With an understanding of the physiologic changes occurring during pregnancy, a careful history and physical examination, and judicious use of laboratory tests and imaging studies, the physician should be able to determine the cause of the patient's pain in the great majority of cases and, in the words of Babler, avoid "the mortality of delay."  相似文献   
134.
OBJECTIVES: To determine a mechanism by which nitric oxide alters induction of stress-induced endothelial cell apoptosis in vitro. Apoptosis is a form of cellular suicide that has been implicated in the pathogenesis of multiple organ dysfunction syndrome. DESIGN: Prospective, controlled trial. SETTING: Research laboratory of a large, academic medical center. SUBJECTS: Cultured primary porcine aortic endothelial cells. INTERVENTIONS: Cells were treated with a range of doses of agents that either spontaneously generate nitric oxide (S-nitroso-N-acetyl-D,L-penicillamine [SNAP] or (Z)-1-[2-(2-aminoethyl)-N-(2-ammonioethyl)amino]diazen-1- ium-1,2-diolate [DETA-NO]) or block nitric oxide production (Nomega-methyl-L-arginine [L-NMA]). The ability of these agents to alter the rate of cell death by apoptosis (induced by the sequence stimuli lipopolysaccharide [LPS] followed by sodium arsenite) was measured. Mechanistic studies included examining the ability of: a) nitric oxide "donors" to alter nuclear factor kappa B (NF-kappaB) DNA binding activity and the level of IkappaBalpha accumulation; and b) a stable cyclic guanosine monophosphate (cGMP) analog (8-bromo-cGMP) to mimic the effect of nitric oxide donors. MEASUREMENTS AND MAIN RESULTS: The sequence LPS/sodium arsenite increased the rate of endothelial cell apoptosis (47.4%, p< .05 vs. control), as measured by fluorescent-activated cell scanning using annexin V/propidium iodide staining. DETA-NO generated nitric oxide (as indicated by an increase in the concentration of the stable end-products of nitric oxide metabolism) and decreased the rate of endothelial cell apoptosis (20.6% at a dose of 2 mM, p=.0001 vs. control). DETA-NO also decreased NF-kappaB DNA binding activity and the apparent accumulation of its endogenous inhibitor, IkappaBalpha. The 8-bromo-cGMP did not mimic the effects of nitric oxide donors (DETA-NO) on apoptosis. CONCLUSIONS: These data suggest that exogenous nitric oxide can block stress-induced endothelial cell apoptosis in vitro. The mechanistic studies are consistent with our hypothesis that inhibitors of NF-kappaB DNA binding activity are associated with protection against apoptosis-inducing stimuli. The results do not support a role for cGMP in mediating the protective effect of DETA-NO in our model.  相似文献   
135.
Regardless of the primary care model used in the long-term care facility, each of the three approaches offers quality care improvement and greater consistency for residents at reduced costs. Of the three, an all licensed nursing staff model could best meet the higher acuity levels of residents and the disintegrating availability of qualified nursing assistants. If nurses are unable to "sell" this model to administration, it may be helpful to pilot the concept one one unit for a period of time and compare resident, family, and staff satisfaction with that of a similar unit. Also, it is critical to compare the financial implications, including cost per resident per day and rate of staff turnover, to weigh the model's effectiveness. This small sampling of five facilities indicates the average cost per resident per day is $10 less when using either the primary team or all licensed staff models than in facilities of comparable size. Hospitals have already passed the time when they have had to work smarter, leaner, and more efficiently. Can long-term care facilities afford not to do the same?  相似文献   
136.
针对传统的两温区气相合成高纯HgI2多晶体方法(工艺1)原料损失多、产量低等缺点,通过工艺优化,采用单温区安瓿旋转高温合成工艺(工艺2)合成了HgI2多晶粉体.对比了两种工艺条件下合成产物的物相和杂质含量,结果表明:相对于工艺1,工艺2中由于安瓿旋转和反应温度高,原料反应充分,HgI2多晶体的产量从占合成产物总量的309/6增大到90%.工艺2中杂质总量在10×10^-6以下,达到HgI2单晶体生长要求.  相似文献   
137.
以枯草芽孢杆菌(Bacillus subtilis)和蜡状芽孢杆菌(Bacillus cereus)为出发菌株,采用紫外诱变的方法获得了2株木聚糖酶高产菌株,酶活分别是原来的17.50倍和17.20倍。选取酶活最高的菌株进行发酵条件的研究。  相似文献   
138.
This paper analyzes the results of 1093 transesophageal (TEE) and transthoracic echocardiographic (TTE) studies made in patients with various cardiovascular diseases in December 1989 to November 1996. The investigation was undertaken to define indications for TEE. Undoubtedly, TEE has some advantages over TTE in diagnosing abnormalities of the descending aorta, thromboses of the left atrium, small vegetations of cardiac valves, insignificant atrial septal defects and in evaluating excursions and systolic thickening of middle and basal segments of the left ventricular anterior wall. However, detection of thrombosis of the left ventricular apex remains to be priority in TTE. TEE was found to supplement TTE and considerably improves the diagnostic quality in cardiovascular diseases.  相似文献   
139.
OBJECTIVE: Our aim was to determine the performance and clinical feasibility of telesonography for the interpretation of fetal anatomic scans sent from a remote location compared with those obtained at a tertiary care prenatal ultrasonography center. STUDY DESIGN: Routine ultrasonographic studies from 35 patients were remotely interpreted. Evaluation included a blinded comparison of the sonographer's assessment of 38 fetal structures with that of the physician at the tertiary care center. Technical evaluation included system reliability and the number of digital telephone lines required for adequate real-time visualization. RESULTS: The mean gestational age at the time of the ultrasonography was 25.84 +/- 6.8 weeks (range 14 to 38). There was complete consistency of interpretation for 25 of 38 (66%) fetal structures. Thirteen structures had discrepancies in visualization, reflecting a difference in the adequacy of visualization, not the normalcy or identity of the structures. Three digital (integrated switching digital network, ISDN) telephone lines were required for real-time visualization. CONCLUSION: Our preliminary experience supports telesonography as a clinically useful tool for remote interpretation of fetal ultrasonographic examinations. Further studies are warranted for the continued evaluation of this emerging technology.  相似文献   
140.
A reversed-phase HPLC method was developed for the kinetic investigation of the acidic hydrolysis of prazepam which was carried out in hydrochloric acid solutions of 0.01, 0.1 and 1.0 M. In addition, a fourth-order derivative method for monitoring the parent compound itself was proposed and evaluated. One intermediate was observed by HPLC, which should be formed from breakage of the azomethine linkage. Further slow hydrolysis of the amide bond led to the benzophenone product that was isolated and identified. The mechanism of hydrolysis was biphasic, showing a consecutive reaction with a reversible step. Relative standard deviation was less than 2% for HPLC and less than 5% for the derivative method. Detection limits were 1.2 x 10(-7) M for the former method and 6.7 x 10(-7)M for the latter. Accelerated studies at higher temperatures were employed. Results of HPLC and fourth-order derivative methods were statistically the same.  相似文献   
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