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91.
Twelve polymorphic microsatellite loci were isolated and characterized for one subspecies of the Xantus’s murrelet (Synthliboramphus hypoleucus scrippsi), a threatened seabird. Using blood samples obtained from 40 birds captured at Santa Barbara Island, California, in April–May 1996, 3–14 alleles per locus were detected, and expected heterozygosity ranged from 0.25 to 0.90. Genotype frequencies showed no departures from Hardy–Weinberg expectations. Linkage is suspected in one pair of loci.  相似文献   
92.
We prospectively evaluated 59 eyes following uneventful phacoemulsification and intraocular lens implantation with optic coherence tomography at one and seven postoperative days (POD). Acute vitreomacular traction was observed in two eyes (3.3%) at the first POD. Spontaneous resolution occurred in both eyes within one week. The temporary visual loss associated with acute vitreomacular traction syndrome may go unnoticed as visual acuity rapidly improves.  相似文献   
93.
目的:比较泪道探通治疗对三个年龄组的先天性鼻泪管阻塞患者的成功率。方法:共180例先天性鼻泪管阻塞患者根据年龄分为3组, I组(4 ~6mo), II组(7 ~12mo)和III组(13 ~24mo),均行泪道探通治疗。症状体征均消失为治疗成功的标准。用卡方检验分析结果。结果:I组治疗成功率为100.0%, II组治疗成功率为88.5%,III组治疗成功率为82.3%,总的治愈率为90.7%。结论:泪道探通治疗的有效性随着年龄的增加降低。在6mo时行泪道探通治疗的孩子成功率最高,能完全消除症状。  相似文献   
94.
Sumatriptan, a 5-HT(1B/1D/1F) receptor agonist, is used to relieve migraine headache. Sumatriptan contracts some arteries either directly or after modest precontraction with non-serotonergic agonists. Sumatriptan can cause myocardial ischaemia and myocardial infarction. While previous in-vitro studies have shown that sumatriptan has no or only weak contractile activity in human omental arteries, recent clinical studies suggest that sumatriptan may induce mesenteric ischaemia. The aim of this study was to investigate the presence of contractile 5-HT(1B) receptors in the human mesenteric artery and to establish whether the weak sumatriptan-induced contractions are amplified by precontraction with various contractile substances. The study was performed in organ baths using endothelium-denuded isolated human mesenteric arteries. Sumatriptan induced concentration-dependent contractions in some mesenteric arteries [ E(max) 61+/-10% of the maximum contraction induced by 80 mM KCl, pD(2) (-log(10)EC(50)) 6.56+/-0.20, n=9]. In the other mesenteric arteries, sumatriptan induced only very weak ( E(max) <5%) or no contraction ( n=13). GR127935 (3 nM), a selective 5-HT(1B) receptor antagonist, antagonized sumatriptan-induced contractions insurmountably in sumatriptan-sensitive arteries. When the resting tension of the arterial rings was increased moderately by threshold concentrations (EC(10)-EC(20) of maximum contraction induced by 80 mM KCl) with the non-5-HT receptor agonists phenylephrine (10-100 nM), histamine (100 nM-1 microM) or the depolarizing agent KCl (4-10 mM), 5-HT(1B) receptor-mediated responses were amplified in sumatriptan-insensitive arteries (with phenylephrine E(max) 82+/-17%, pD(2) 6.64+/-0.20, n=7; with histamine E(max) 107+/-26%, pD(2) 6.16+/-0.14, n=6; with KCl E(max) 78+/-16%, pD(2) 6.45+/-0.15, n=7). These results show that sumatriptan induced concentration-dependent contractions in sumatriptan-sensitive mesenteric arteries and that 5-HT(1B) receptors were present and active in these vessels. However, in sumatriptan-insensitive arteries, precontraction is required for sumatriptan to induce concentration-dependent contractions. These findings suggest that sumatriptan may induce ischaemia in human mesenteric vasculature directly or in the presence of precontractile risk factors.  相似文献   
95.
The development of resistance to current antifungal therapeutics drives the search for effective new agents. The fact that some acetophenone-derived Mannich bases had shown antifungal activities in our previous studies led us to design and synthesize acetophenone-derived bis Mannich bases, B1-B5, bis(beta-aroylethyl)methylamine hydrochlorides, to evaluate their antifungal activity. These bis Mannich bases were then converted to the corresponding piperidinols, C1-C5, which are structural isomers of bis derivatives, 3-aroyl-4-aryl-1-methyl-4-piperidinol hydrochlorides, to see alterations in biological activity. A stability study of B1 and Cl was also carried out to estimate whether they alkylate the thiols. All compounds studied have shown antifungal activity, especially against dermatophytes (Trichophyton rubrum, Trichophyton mentagrophytes, Trichophyton tonsurans, and Microsporum canis), in the concentration range studied (2-128 microng/ml). The activity was especially apparent against T. tonsurans. All compounds had at least equal antifungal activity compared with the reference compound amphotericin-B against T. tonsurans. Bis Mannich bases were generally found to be more potent compounds than their structural isomer piperidinols. The results of our stability studies suggest that thiol alkylation may contribute to the antifungal activity of the Mannich bases synthesized. Even though all compounds showed antifungal activity against dermatophytes, bis Mannich bases B1, B2, B4, and B5 appear to have potential for developing novel antifungal agents against dermatophytes.  相似文献   
96.
HYPOTHESIS: Various forms of electrical stimulation can improve wound healing in different tissues, but their application to gastrointestinal tract healing has not been investigated. We assumed that positively charged diethylaminoethyl cross-linked dextran bead (diethylaminoethyl Sephadex [DEAE-S]) particles would have a beneficial effect on the healing of colonic anastomoses. DESIGN: Experimental animal study. SETTING: Animal research laboratory of a university hospital. ANIMALS: Forty female Wistar albino rats. INTERVENTIONS: Right colonic transection and anastomosis was performed in 5 animal groups. The control group received no treatment; the placebo group, methylcellulose gel; and the DEAE-S group, DEAE-S in methyl cellulose gel applied topically around the anastomoses. The fecal peritonitis (FP) group underwent cecal ligation and perforation simultaneously with the anastomosis to cause FP; the FP + DEAE-S group also received DEAE-S applied around the anastomoses. MAIN OUTCOME MEASURES: After the completion of postoperative day 4, all rats were killed. Anastomotic bursting pressures and hydroxyproline concentrations in perianastomotic tissue were measured and compared. RESULTS: Mean bursting pressures were 115.1 mm Hg in the control group, 113.6 mm Hg in the placebo group, 159.4 mm Hg in the DEAE-S group, 62.8 mm Hg in the FP group, and 121.1 mm Hg in the FP + DEAE-S group (P =.001, 1-way analysis of variance [ANOVA]). The differences between the control vs DEAE-S groups, placebo vs DEAE-S groups, and FP vs FP + DEAE-S groups were significant (P<.05, t test). Mean hydroxyproline concentrations were 5.2 microg/mg in the control group, 4.9 microg/mg in the placebo group, 5.6 microg/mg in the DEAE-S group, 4.5 microg/mg in the FP group, and 5.4 microg/mg in the FP + DEAE-S group (P =.09, 1-way ANOVA). The difference between the FP and FP + DEAE-S groups was significant (P =.04, t test). CONCLUSIONS: A positively charged particle, DEAE-S, improves healing of colonic anastomoses in healthy rats and in rats with FP. This inexpensive, nontoxic material is easily applied and deserves further evaluation in gastrointestinal tract healing.  相似文献   
97.
Weight loss in response to caloric restriction is variable. Because skeletal muscle mitochondrial proton leak may account for a large proportion of resting metabolic rate, we compared proton leak in diet-resistant and diet-responsive overweight women and compared the expression and gene characteristics of uncoupling protein (UCP)2 and UCP3. Of 1,129 overweight women who completed the University of Ottawa Weight Management Clinic program, 353 met compliance criteria and were free of medical conditions that could affect weight loss. Subjects were ranked according to percent body weight loss during the first 6 weeks of a 900-kcal meal replacement protocol. The highest and lowest quintiles of weight loss were defined as diet responsive and diet resistant, respectively. After body weight had been stable for at least 10 weeks, 12 of 70 subjects from each group consented to muscle biopsy and blood sampling for determinations of proton leak, UCP mRNA expression, and genetic studies. Despite similar baseline weight and age, weight loss was 43% greater, mitochondrial proton leak-dependent (state 4) respiration was 51% higher (P = 0.0062), and expression of UCP3 mRNA abundance was 25% greater (P < 0.001) in diet-responsive than in diet-resistant subjects. There were no differences in UCP2 mRNA abundance. None of the known polymorphisms in UCP3 or its 5' flanking sequence were associated with weight loss or UCP3 mRNA abundance. Thus, proton leak and the expression of UCP3 correlate with weight loss success and may be candidates for pharmacological regulation of fat oxidation in obese diet-resistant subjects.  相似文献   
98.
Gulácsi L 《Orvosi hetilap》2002,143(14):707-712
The history of the evidence based medicine, health technology assessment, health economics and quality improvement proved to be a success story in developed countries. It is partly due to that change in the attitude towards health care occurred in the past ten or fifteen years. Two major factors played important roles in this process. On the one hand, the booming health care costs in developed countries, and on the other, the health benefit was not proportional to costs. First, governments around the world applied the tool of cutting costs, which proved to be uneffective even in mid-term. It was soon revealed that people prefer good-quality health care rather than the cheap one. These disciplines are having a more and more considerable influence on medical care and nursing. However, impacts on health care are not automatic and can be most different regarding both their quantity and nature. They may result in a significant improvement in prevention, diagnostics, cure and care, and may yield a more appropriate use of ever-limited resources.  相似文献   
99.
Valproic acid is commonly used in the management of childhood epilepsy. The known hematologic side effects of the drug are hemorrhagic diatheses, thrombocytopenia, and hypofibrinogenemia. We studied coagulation parameters in 29 epileptic children receiving valproic acid for at least 6 months. Their ages ranged between 2 and 18 years (10.2 +/- 4.9 years). The total valproic acid dose was 250 to 1000 mg/day equivalent to 20 to 30 mg/kg/day. Treatment duration ranged from 6 to 57 months. These children had not previously had a hemostatic defect and had no family history of bleeding disorders. Platelet count, prothrombin time, activated partial thromboplastin time, bleeding time, fibrinogen, platelet aggregation assays, and ristocetin cofactor activity levels were determined in all of the patients, but von Willebrand's factor antigen levels could be determined in only 14 patients. The values of von Willebrand's factor antigen ranged from 53 to 218% (104.1 +/- 42.3), and ristocetin cofactor activity levels ranged from 11.5 to 218% (94.5 +/- 43.1). Six of the 29 children (20.7%) had decreased values of ristocetin and cofactor activity and were considered to have acquired von Willebrand's disease. The decreases in coagulation parameters were not dependent on either valproic acid dose or treatment duration. Two patients with low ristocetin cofactor activity values had mild epistaxis, which did not require discontinuation of therapy. In patients receiving valproic acid therapy, this side effect must be considered, especially before surgical intervention and serious traumatic conditions.  相似文献   
100.
BACKGROUND AND PURPOSE: Patients referred to tertiary care centers frequently arrive with images obtained at outside institutions; these images require reinterpretation. We assessed the clinical value of reinterpreting cross-sectional imaging studies of patients with head and neck cancer, in the setting of a multidisciplinary cancer center. METHODS: Outside CT and MR images of 136 patients with known or presumed head and neck cancer were reinterpreted by a neuroradiologist. Clinical history and findings on physical examination were available. Reinterpretation was performed before review of outside reports, which were subsequently compared with those generated at the cancer center. Changes in interpretation were noted, and their effects on TNM staging, patient care, and prognosis were assessed. Reliability and statistical significance of rates of change in diagnosis were analyzed with 95% confidence intervals (CIs) and the sign test, respectively. Verification of change in diagnosis was confirmed by pathologic analysis (75%), characteristic radiologic findings (18%), or clinical and imaging follow-up (7%). RESULTS: Change in interpretation occurred in 56 patients (41%) (95% CI: 33-49%, P <.001). Forty-six patients (34%) had a change in T, N, and/or M staging (26-42%, P <.001). Change in T stage occurred in 27 cases (20%) (13-27%, P <.001) (upstaged in 22, downstaged in five), and a change in N stage in 26 cases (19%) (12-26%, P <.001) (upstaged in 20, downstaged in six). Two patients (1.5%) had missed systemic metastases. Three patients with an initial diagnosis of cancer were found to be cancer-free, and six patients had a diagnosis of new second primary cancers that were missed at original interpretation. One patient had a missed middle cerebral artery aneurysm. Changes in image interpretation altered treatment in 55 (98%) of 56 patients and affected prognosis in 53 patients (95%) (P <.001). CONCLUSION: Reinterpretation of cross-sectional images in the setting of a multidisciplinary cancer center has a significant effect on staging, management, and prognosis in patients with head and neck cancer.  相似文献   
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