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1.
PURPOSE: The aim of this study was to determine if the concomitant use of ketorolac 0.4% and cyclosporin-A improves patient comfort during the induction phase in treating chronic dry eye disease. METHODS: Patients (n = 52) with clinically diagnosed dry eye were randomized to receive either cyclosporin-A monotherapy twice-daily (BID) or a BID adjunctive regimen of ketorolac, followed by the instillation of cyclosporin-A 10 min later. Study visits were at baseline, week 2, and week 6. At each study visit, patients underwent an evaluation for corneal staining, Schirmer's scores, and tear break-up time tests. Patients were asked to rate ocular comfort on a 4-point scale and to complete the ocular surface disease index (OSDI). Changes from baseline readings were recorded at week-2 and week-6 visits, and final patient success on treatment regimen was evaluated at week 6. RESULTS: After 6 weeks, the mean ocular comfort score of adjunctive patients improved 2.55 +/- 0.95 points, versus 1.53 +/- 0.91 points for monotherapy (P = 0.309). The adjunctive regimen provided significantly greater corneal staining reductions versus monotherapy, mean reduction in staining of 1.74 +/- 0.9, versus 1.27 +/- 0.56 (P = 0.044). CONCLUSIONS: Concurrent ketorolac 0.4% use with cyclosporin-A significantly reduced corneal staining and increased comfort in the induction phase.  相似文献   
2.
Piroximone (MDL 19,205), a new imidazolone derivative, was given intravenously to 14 patients with congestive heart failure (NYHA class II-III), while under constant daily doses of digitalis and diuretics. In the first 3 patients, we determined the dose safely eliciting a favorable hemodynamic response. The subsequent 11 patients received 1 mg/kg of piroximone intravenously, and the hemodynamic effects were compared with those of sodium nitroprusside (SN) at a dose-lowering mean blood pressure by 10-20 mm Hg. Piroximone increased heart rate (13.2 +/- 2.0 beats/min, mean +/- SEM) and lowered mean arterial pressure (9 +/- 2.3 mm Hg). Both agents reduced similarly wedge pressure (6.5 +/- 2.9 and 9 +/- 2.9 mm Hg, respectively, for SN and piroximone) and total peripheral resistance. Cardiac index was increased less by SN (15%) than piroximone (48%) (p less than 0.001), and stroke work index significantly enhanced only by piroximone (p less than 0.001). The changes in loading conditions induced by the two agents being similar, it is likely that piroximone not only acts by peripheral vasodilation, but also possesses positive inotropic properties. Myocardial oxygen demand, assessed indirectly by tension-time index, was not affected by piroximone. Thus, piroximone appears to combine well-balanced vasodilator and inotropic properties which make this new agent potentially very useful for the management of congestive heart failure.  相似文献   
3.
The main features of central 5-HT1 receptors   总被引:1,自引:0,他引:1  
The 5-HT1 receptor family comprises five different pharmacologic subtypes, designated 5-HT1A, 5-HT1B, 5-HT1C, 5-HT1D, and 5-HT1E, whose common property is to bind 5-HT with nanomolar affinity. Recent investigations with molecular biology approaches led to the cloning and sequencing of 5-HT1A receptors in the rat and in the human, and of the 5-HT1C receptor in the rat. Although the 5-HT1A and 5-HT1C protein binding subunits exhibit the same structure with seven hydrophobic transmembrane domains, an extracellular N terminal and an intracellular C tail, their respective amino-acid sequences are markedly different. Indeed, a higher degree of sequence homology is found between the 5-HT1C and 5-HT2 receptors than between the former and 5-HT1A receptors, suggesting that the 5-HT1C subtype in fact belongs to the 5-HT2 class of central 5-HT receptors. All other 5-HT1 receptor subtypes are negatively coupled to adenylyl cyclase, whereas the 5-HT1C subtype, like 5-HT2 receptors, is positively coupled to phospholipase C. The respective regional distributions and regulatory properties, as well as pending questions regarding the ultrastructural localization, synthesis, mutual interactions, and axonal flow of 5-HT1 receptor subtypes, are also discussed.  相似文献   
4.
During 1989, 316 members of a cohort of homosexual men were tested for HIV-specific DNA by the polymerase chain reaction (PCR) using a pair of gag-region primers. Of 125 HIV-seronegative subjects, 123 (98.4%) were PCR-negative while 158 (82.7%) of 191 HIV-seropositive subjects were PCR-positive. Fewer of the 33 subjects who were seropositive and PCR-negative were at Centers for Disease Control (CDC) stage IV than the seropositive, PCR-positive subjects (6 versus 25%; P = 0.030). The seropositive, PCR-negative group had higher mean CD4 counts (640 versus 490 x 10(6) cells/l; P = 0.006), higher CD4: CD8 ratios (0.92 versus 0.64; P = 0.004), lower immunoglobulin (Ig) G levels (1290 versus 1645 mg/dl; P = 0.002), lower IgA levels (168 versus 251 mg/dl; P less than 0.001), and lower C1q binding activity (8 versus 14%; P = 0.010) than the seropositive, PCR-positive subjects. The median rate of CD4 cell decline in the 3 years preceding the PCR sample was less marked in the seropositive, PCR-negative group than the seropositive, PCR-positive group (-58 versus -77 x 10(6) cells/l per year; P = 0.028). To control for duration of infection, we restricted the analysis to the subgroups of 11 seropositive, PCR-negative subjects and 34 seropositive, PCR-positive subjects who had seroconverted earlier in the cohort study. Both subgroups had similar durations of infection, yet the same pattern of differences persisted.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
5.
背景:长寿个体年龄相关疾病的发病率较低且发病时凤明显后延,其家族成员可能遗传有某些调节衰老过程或疾病敏感性的因子。  相似文献   
6.
The drug discrimination paradigm (DD) was used to evaluate behavioral differences of rats selectively bred for differential ethanol drinking preferences. Seventh-generation high alcohol-drinking (HAD) and low alcohol-drinking (LAD) rats were trained to discriminate between ethanol (0.5 g/kg, IP) and saline vehicle, following a 2-min presession interval (PI), using an FR-10 schedule of reinforcement. The HAD line was more responsive than the LAD line to the stimulating effect of ethanol as measured by total response rates. ED50 values of 0.239 and 0.244 g/kg for the HAD and LAD lines, respectively, do not reflect any difference in the discriminative effects of ethanol. Response rates during DD indicated a dissociation of rate-increasing effects and discriminative performance following ethanol. In addition to differential drinking preference, these data suggest that selective breeding for the HAD and LAD animals also involves the stimulant action of ethanol but not on the discriminative effects.  相似文献   
7.
C M Hall  N Schechter 《Neuroscience》1991,41(2-3):695-701
Goldfish retinal explants were used to study optic tectum participation in the regulation of intermediate filament protein synthesis in retinal ganglion cells during optic nerve regeneration. Retinas were explanted at various times after removal of the contralateral optic tectum. The synthesis of the intermediate filament proteins ON1 and ON2 in the cultures was quantitated by labeling with [35S]methionine, followed by two-dimensional gel electrophoresis, autoradiography, and densitometry. Neuritic growth from the explants was quantitated based on fiber length and density. In retinal explants placed in culture after 23 days of optic nerve regeneration, the synthesis of ON1 and ON2 was reduced when the tectum had been ablated. In contrast, synthesis of these proteins in explants placed in culture at an earlier stage of regeneration was not affected by tectal ablation. At all time points tested, neuritic outgrowth from retinal explants was stimulated by tectal ablation. These findings indicate that the synthesis of the ON1 and ON2 intermediate filament proteins during regeneration is not directly regulated by axonal volume. Further, our findings suggest that interaction between growing axons and tectum is important for sustained expression of these proteins during the later stages of optic nerve regeneration.  相似文献   
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Isoniazid chemoprophylaxis is not recommended for all persons infected with tubercle bacilli. Because of the small but significant risk of isoniazid hepatotoxicity, chemoprophylaxis is reserved for only those at the highest risk of tuberculosis activation. To evaluate this policy, we performed a cost-effectiveness analysis of isoniazid chemoprophylaxis for two populations with positive tuberculin skin tests: recent tuberculin converters, who are at high risk for activation, and older tuberculin reactors, who have a low risk for activation and for whom chemoprophylaxis is not now recommended. The cost-effectiveness ratios found were stable, despite wide variations in model assumptions and probability estimates. For high-risk tuberculin reactors, chemoprophylaxis resulted in net medical care monetary savings, extended life expectancy, and fewer fatal illnesses. For low-risk tuberculin reactors, chemoprophylaxis resulted in positive, but small, health effects. Because the cost to gain these positive effects were also small, the resulting cost-effectiveness ratios were reasonable and in the realm of accepted prevention strategies: $12,625 to gain one year of life and $35,011 to avert one death. These findings suggest that the current policy is too restrictive and that many in the large population of low-risk tuberculin reactors should be considered for isoniazid chemoprophylaxis.  相似文献   
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