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71.
复方栀子冲剂栀子甙薄层扫描测定 总被引:11,自引:0,他引:11
应用薄层扫描法测定了复方栀子冲剂中栀子甙的含量,对实验条件,以正交试验法进行优选,确定了最佳方案,排除了干扰,得到了满意的效果。 相似文献
72.
A Joseph S Abraham S Bhattacharji J Muliyil K R John N Ethirajan K George K S Joseph 《World health forum》1988,9(3):336-340
A study was made on the causes of unsatisfactory progress in immunization coverage in an area of Tamil Nadu, southern India. The findings led to the appointment of additional community health workers (CHW), improvement in supervision, the enhancement of accessibility to services through an increase in the number of peripheral clinics and the organizing of temporary clinics, and the concentration of effort on underprivileged groups. As a result, immunization coverage was more than doubled. The Community Health and Development Project, a primary health care program serving 68 villages since 1981 with a population of about 80,000 was the site of the study which was conducted by discussions with staff and various members of the community. Issues explored were nonacceptance or dropout reasons, and specific factors affecting immunization coverage. A special effort was made to obtain the views of staff working at the periphery, particularly CHWS. The service area was divided into 4 sectors and the CHWS, auxiliary nurse midwives, community health nurses and other development staff in each were brought together for discussions. Views were also solicited from mothers' clubs and youth groups and in meetings with village leaders. Issues raised were further considered by supervisory staff. Statistical studies and other studies were done to clarify doubtful issues and test hypotheses emerging from the discussion. Poor immunization coverage was linked to inadequate supervision of CHWs, scattered communities (village with houses clustered together had better acceptance rates), difficulty of access to health services (distance factors), and low economic and educational status. In light of the study findings, community health workers were increased from 42 in 1984 to 57 in 1987 to cover all the villages, with modifications in selection method to make the worker acceptable to all sections of the villages; abolishment of the auxiliary nurse midwife and addition of a new category, health aide, to link the CHW and the community health nurse, increase of peripheral clinics from 37 to 75 and holding of more temporary clinics, more efforts to reach all socioeconomic groups and increased health education through film shows, drama, and work with village groups. 相似文献
73.
Joseph Leighton 《Methods in Cell Science》1992,14(4):201-207
Summary Formation of epithelial tissues in culture so that they become facsimiles in their structure of such tissues in nature requires procedures that comply with several spatial imperatives: a) three-dimensional growth; b) histophysiologic conditions that provide, concurrently, gradients of maturation and of diffusion of metabolites; and c) growth as layers of cells without free edges. Many steps have been required in the evolution of these methods. Two systems are described here in sufficient detail to serve as a manual. Three-dimensional growth of masses of epithelial tissue is accomplished in matrix culture using Gelfoam sponge and collagen-coated cellulose sponge. Radial gradient culture, a recent development, provides conditions that comply with the requirements of histophysiologic gradients and of epithelial tissue growth in layers without interruption in their continuity. 相似文献
74.
Jeffrey A. Gray Stephen N. Mitchell Michael H. Joseph Grigory A. Grigoryan Sharon Dawe Helen Hodges 《Drug development research》1994,31(1):3-17
Data are reviewed, largely from experiments in the authors'laboratory, that suggest three modes of action of systemic nicotine in producing three different types of effect upon behavior and cognitive function. (1) Preexposure of a stimulus without consequence makes it harder subsequently to form associations to that stimulus, a form of selective attention known as latent inhibition. Latent inhibition is blocked by nicotine, an effect that is apparently mediated by a nicotine-induced increase in dopamine release in the nucleus accumbens. (2) A single dose of nicotine proactively increases the partial reinforcement extinction effect measured several weeks later: that is, resistance to extinction is decreased by nicotine in animals that have been trained on a continuous reinforcement schedule, and increased in animals trained on a partial reinforcement schedule. This effect appears to be due to increased synthesis of tyrosine hydroxylase in the cell bodies of noradrenergic neurons in the locus coeruleus, followed by axonal transport to the hippocampus and increased synthesis and release of noradrenaline in that structure. (3) Nicotine improves vigilance in animals with cognitive deficits due to destruction of the forebrain cholinergic projection system, either as a consequence of excitotoxic lesions of the nuclei of origin of this system or after prolonged alcohol consumption; and also in human subjects with Alzheimer's disease (in which this system undergoes degeneration). This effect is most likely due to an action at denervated cholinergic synapses in the hippocampus and neocortex. © 1994 Wiley-Liss, Inc. 相似文献
75.
For the treatment of intraabdominal infection, single-agent antimicrobial regimens such as β-lactams with good antianaerobic activity are frequent alternatives to combination regimens such as aminoglycosides or aztreonam plus an antianaerobic agent such as clindamycin or metronidazole. The major issues in selecting a regimen are relative efficacy, potential for adverse drug effects, and cost. Single agents are clearly equivalent to combinations in preventing infectious complications after penetrating abdominal trauma and in treating established intraabdominal infections of mild to moderate severity or in relatively low-risk patients. A few trials demonstrated their equivalency in patients at high risk of mortality, although experience is limited. Single-agent regimens may reduce the risks of adverse drug effects compared with combination regimens, but they are not always less expensive. 相似文献
76.
Dr. Joseph A. Paladino Pharm.D. Dr. Miguel A. Rainstein M.D. FACS Mrs. Deborah J. Serrianne R.N. Dr. John E. Przylucki M.D. FACS Dr. Lynda S. Welage Pharm.D. Dr. Mario L. Collura M.D. FACS Dr. Jerome J. Schentag Pharm.D. FCCP 《Pharmacotherapy》1994,14(6):734-739
This double-blind study compared ampicillin-sulbactam 3 g versus cefoxitin 2 g in 136 adult patients at risk for developing an infection after abdominal surgery. Separate randomization schedules were used for colorectal, upper gastrointestinal/biliary, and other abdominal procedures. Study antibiotics were administered within 30 minutes before incision and repeated 6 hours later. Patients having colorectal surgery received a third dose of antibiotic 6 hours after the second. Efficacy evaluations were made on 123 patients, 62 in the ampicillin-sulbactam group and 61 in the cefoxitin group. The overall postoperative infection rates were 12.9% for ampicillin-sulbactam and 9.8% for cefoxitin (p>0.05); one wound infection occurred in each group. Adverse events were experienced by 13.2% of the ampicillin-sulbactam and 19.1% of the cefoxitin recipients (p>0.05). Cost-minimization analysis revealed that ampicillin-sulbactam was a cost-effective alternative to cefoxitin for the prevention of infection after abdominal surgery. 相似文献
77.
Robert C. Flanigan Joseph H. Saiers Michael Wolf Eric H. Kraut Anthony Y. Smith Brent Blumenstein E. David Crawford 《Investigational new drugs》1994,12(2):147-149
Summary The Southwest Oncology Group (SWOG) studied the response rate and toxicity of merbarone (1,000 mg/m2 IV continuous infusion days 1–5, q 21 days) in patients with advanced metastatic renal cell carcinoma. Among 36 eligible patients, there was one partial response for a response rate of 3% (95% C.I. 0.1–15%). There were no mixed responses. There were no treatment related deaths or adverse drug reactions. Significant anemia, diarrhea, and hypercalcemia were observed. Mild to moderate degrees of malaise/fatigue/lethargy, dizziness/vertigo, hyperglycemia, creatinine increase, nausea, vomiting, weight loss, pedal edema, dyspnea, and granulocytopenia were noted. Merbarone does not have significant activity as a single agent in advanced renal cell carcinoma. 相似文献
78.
The electrophysiological effects of dicentrine on the conduction system of rabbit heart. 总被引:3,自引:2,他引:1 下载免费PDF全文
1. The electrophysiological effects of dicentrine, an aporphine alkaloid isolated from the root of Lindera megaphylla, were examined in the Langendorff perfused rabbit heart and rabbit isolated cardiac cells. 2. Standard electrophysiological characters were measured in the Langendorff perfused rabbit heart (control study) and after 5 min exposure to 1, 3 and 9 microM of dicentrine and during the subsequent recovery phase sequentially (n = 7). The same study protocols were performed in 0.5 to 4.5 microM quinidine (n = 7), 18 to 162 microM procainamide and N-acetylprocainamide (n = 7) for comparison. 3. The results showed that the spontaneously beating heart rate and the sinoatrial (SA) and atrioventricular nodal (AH) conduction time were not significantly affected by dicentrine but were significantly suppressed by the higher doses of quinidine (4.5 microM) and procainamide (162 microM). 4. The His-Purkinje conduction time was significantly increased by the higher dose of dicentrine, quinidine and procainamide. 5. The ventricular repolarization time and its effective refractory period were significantly increased by the higher dose of dicentrine and the other agents. 6. The effective refractory period of the atrium, AV node and His-Purkinje system were also significantly increased by dicentrine and the other agents. 7. A voltage clamp study revealed that the prolongation of atrial action potential duration by dicentrine (9 microM) was associated with a significant inhibition of the transient potassium outward current. As well as inhibition of the transient outward current, a significant inhibition of the sodium inward current by dicentrine was found.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
79.
Dr. Andrew G. Bostom M.D. Dr. Anne L. Hume Pharm.D. Dr. Charles B. Eaton M.D. Dr. Joseph P. Laurino Ph.D. Ms. Lisa R. Yanek B.A. Ms. Mary S. Regan B.S. Mr. William H. McQuade M.P.H. Dr. Wendy Y. Craig Ph.D. Ms. Gayle Perrone M.B.A. Dr. Paul F. Jacques Sc.D. 《Pharmacotherapy》1995,15(4):458-464
Study Objective . To determine the efficacy of high-dose ascorbate supplementation in lowering lipoprotein(a) [Lp(a)] levels in patients with premature coronary heart disease (CHD). Design . Randomized, double-blind, placebo-controlled trial. Setting . Outpatient clinic. Patients . Forty-four patients with documented premature CHD. defined as confirmed myocardial infarction and/or angiographically determined stenosis of 50% or greater in at least one major coronary artery before age 60 years. Interventions . Patients were block randomized on the basis of age, gender, and screening Lp(a) concentrations to receive ascorbate 4.5 g/day or placebo for 12 weeks. Measurements and Main Results . High-dose ascorbate was well tolerated and produced a marked elevation in mean plasma ascorbate levels (+1.2 mg/dl; p<0.001). Multiple linear regression analysis revealed no significant effect of supplementation on postintervention Lp(a) levels (p=0.39) in a model that included treatment group assignment, and baseline Lp(a) levels. Conclusions . Our findings do not support a clinically important lowering effect of high-dose ascorbate on plasma Lp(a) in patients with premature CHD. 相似文献
80.
Alex Westerband Joseph L. Mills Scott S. Berman Glenn C. Hunter 《Annals of vascular surgery》1997,11(1):14-19
n = 69) normal; Group B (n= 29), abnormal, severe defects; Group C (n= 56), abnormal, mild–moderate defect. RCA detected 32 defects in Group B: 10 internal carotid (ICA), seven endpoint flaps,
two kinks, one dissection; 16 external carotid (ECA), 10 severe endpoint defects and six total occlusion; six common carotid
(CCA), five irregular proximal shelfs, one web. Thirty of 32 defects were successfully repaired as confirmed by normal repeat
RCA studies; one ECA defect was not repaired and the ICA dissection was irreparable. In Group C, 67 mild–moderate defects
were identified, but not corrected. These included <30% stenosis in the ICA (12), ECA (18), CCA (24), and vein patch corrugation
or irregularity (13). For the entire series the postoperative ICA occlusion rate was 2% (3/154), stroke rate 2.6% (4/154),
and a subsequent >50% restenosis rate of 7% (11/154). The yield from routine carotid completion arteriograms was significant,
with 19% of studies identifying a severe defect that required repair. Although the difference in stroke rates and restenosis
between the different groups did not reach statistical significance, patients with normal intraoperative arteriograms initially
or after correction of a significant RCA defect had no early carotid occlusion (p= 0.05, Fisher's exact test) compared to patients with residual RCA defects. All early carotid occlusions occurred in patients
with unrepaired defects. We conclude that RCA is an important method of quality control after CEA and exerts a subtle, but
real, reduction in postoperative complications. 相似文献