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11.
Rafael T Mikolajczyk Maren Bredehorst Nadia Khelaifat Claudia Maier Annette E Maxwell 《BMC public health》2007,7(1):21
Background
The prevalence of depression is increasing not only among adults, but also among adolescents. Several risk factors for depression in youth have been identified, including female gender, increasing age, lower socio-economic status, and Latino ethnic background. The literature is divided regarding the role of acculturation as risk factor among Latino youth. We analyzed the correlates of depressive symptoms among Latino and Non-Latino White adolescents residing in California with a special focus on acculturation. 相似文献12.
We use pulmonary function measurements on pre-adolescent children and indoor air pollution measurements in the homes of these children to illustrate estimation techniques for linear regression models containing independent variables measured with error. In our data set, replicate measures of indoor air pollutant concentrations provide one method of estimating measurement error variances. Surrogate information in the form of cigarettes smoked is also available for the pollutant of interest. Several estimation procedures are presented, and we combine two estimators, one based on surrogate information and one based on replication information, using generalized least squares. 相似文献
13.
Collateral airway resistance was measured during inflation of an excised lung lobe or a segment within the lobe. Gas blown into the outer lumen of a double lumen catheter (Vcoll) inflated the segment and exited via collateral airways. Pressure at the catheter tip (Pct) was measured through the inner lumen of the catheter, and transpulmonary pressure (Pao) was measured at the lobar bronchus. A pleural capsule measured pressure in the segmental subpleural alveoli (Ps). The segment was inflated with helium (He), air, or sulfurhexafluoride; the lobe was ventilated with air. Collateral airway resistance [Rcoll = (Pct-Pao)/Vcoll], intrasegmental airway resistance [Rs = (Pct-Ps)/Vcoll], and resistance of airways passing through the segment-lobar interface [Ri = (Ps-Pao)/Vcoll] were calculated. Rcoll, Rs, and Ri were decreased by lobar inflation and increased by segment inflation. The latter increase was due to nonlaminar flow in intrasegmental airways. The major resistance was Ri when Vcoll was laminar or transitional. Moody plots suggested that lobar inflation caused intrasegmental airway dilation whereas segment inflation did not affect segment airway geometry. 相似文献
14.
Production of murine hybrid-hybridomas secreting bispecific monoclonal antibodies for use in urease-based immunoassays 总被引:1,自引:0,他引:1
To produce bispecific antibodies (BiAbs) for enzyme immunoassay (EIA) to replace antibody-enzyme conjugates, we developed a panel of 8-azaguanine/ouabain-resistant anti-urease variant hybridoma cell lines for use in hybridoma-hybridoma fusions. These variants represent mouse immunoglobulin subclasses IgM, IgG1, IgG2a, and IgG2b and have growth rates equal to those of the parental hybridomas. We fused an anti-urease-secreting variant hybridoma with an anti-human choriogonadotropin (hCG)-secreting hybridoma (both of IgG1 subclass) and selected the desired product with growth media containing hypoxanthine-aminopterin-thymidine (HAT) and ouabain. Over 95% of the resulting hybrids secreted anti-urease, and 60% of these secreted anti-hCG. The bispecific nature of secreted antibodies was demonstrated in a simultaneous EIA where BiAbs, hCG, and urease (EC 3.5.1.5) were incubated together in anti-hCG-coated microwells. As little as 25 int. units of hCG per liter could be reliably detected, which is equivalent to that for antibody-enzyme conjugates in EIA. 相似文献
15.
PURPOSE: To describe a patient diagnosed with pheochromocytoma in the third trimester of pregnancy and discuss the perioperative and anesthetic management. CLINICAL FEATURES: A 32-yr-old previously healthy woman (gravida 4, para 2) presented to our tertiary care obstetrical hospital at 34 weeks five days gestation with a history of labile blood pressure and severe hypertension. A week prior to admission she began having episodes of severe headache, dizziness, sweating and nausea. On a routine obstetric visit she was noted to be severely hypertensive with a blood pressure of 200/120 mmHg. Biochemical investigations confirmed the diagnosis of pheochromocytoma and magnetic resonance imaging demonstrated a 3 cm x 3 cm right adrenal mass. The patient was invasively monitored in the intensive care unit and treated with alpha- followed by beta-blockade with phenoxybenzamine and metoprolol. A multidisciplinary conference was organized involving endocrinology, anesthesiology, general surgery and obstetrics to determine the most appropriate management of the patient. An uncomplicated laparoscopic adrenalectomy was performed following a period of recovery after an uneventful elective Cesarean delivery. CONCLUSIONS: The primary goals in the management of pheochromocytoma in pregnancy are early diagnosis, avoidance of a hypertensive crisis during delivery and definitive surgical treatment. Timing of surgical resection will depend on the gestational age at which diagnosis is made. Cesarean section is the preferred mode of delivery when the tumour is still present. This case illustrates that with antenatal diagnosis, advanced methods of tumour localization, adequate preoperative adrenergic blockade and team planning, pheochromocytoma in pregnancy can be treated successfully. 相似文献
16.
Subclinical peripheral nerve involvement in AIDS: an electrophysiological and pathological study. 下载免费PDF全文
G N Fuller J M Jacobs R J Guiloff 《Journal of neurology, neurosurgery, and psychiatry》1991,54(4):318-324
Thirty patients with AIDS without symptoms or signs of peripheral neuropathy were compared electrophysiologically with 23 age and sex matched healthy controls. The patients had a mean reduction in the amplitude of common peroneal compound muscle action potentials of 37% (95% CI 11-70%) and of sural sensory action potentials of 34% (CI 18-49%). Mean conduction velocity of both motor and sensory nerves was reduced by between 1 and 7 m/s, with a prolongation of F waves corrected for height of 5% in the arms and 13% in the legs. The distal motor latencies were unchanged. These changes did not correlate with the duration of AIDS, degree of immunosuppression (CD4 count), Body Mass Index, albumin or vitamin B12 level. Four patients had subclinical mononeuropathies. Sural nerve taken at necropsy from five asymptomatic AIDS patients had evidence of axonal degeneration without inflammation or demyelination. There was a mean reduction in myelinated fibre density of 30.5% (CI 10-51%) compared with eight age matched sudden death controls (p = 0.01). This loss principally affected the larger fibres. The pathological and electrophysiological changes indicate axonal degeneration and are similar to those seen in other chronic disorders and in normal ageing. It is concluded that this axonal degeneration is not specific to HIV. 相似文献
17.
18.
We have measured sequentially the concentrations of ethoxzolamide (6-ethoxybenzothiazole-2-sulfonamide) in ocular tissues following its intravenous or topical administration to normal albino rabbits. This was done in parallel with determinations of intraocular pressure (IOP) measured by tonometer or direct manometry. Ethoxzolamide was used because of its very high activity against carbonic anhydrase and experience showing that there is little or no other receptor in tissues. During the course of these experiments it was discovered that the lipid-soluble ethoxzolamide is converted in vivo to a water-soluble metabolite, while retaining high activity against the enzyme. Presumably this is the 6-O-glucuronide adduct. At the minimal dose for maximal effect (4 mg kg-1 i.v. at 45 min) the IOP lowering was 4.2 mmHg, the concentration in anterior uvea was 2.5 mumol kg-1, and the fractional inhibition of the enzyme (i) was 0.9995. The effect of free drug in the anterior uvea and other tissues. Following topical administration i was measured as a function of drug and enzyme in ciliary process. IOP lowering at 1 hr was -1.9 mmHg and i = 0.9993. By 4 hr i = 0.9980 and the pharmacological effect disappeared. At 8 hr the concentration of ethoxzolamide in the ciliary process is 0.4 mumol kg-1, essentially that of enzyme, with no free drug present: drug is now a marker for enzyme. Ethoxzolamide also labels the red cell carbonic anhydrases in the rabbit as well as other species including man. There appears to be no ethoxzolamide receptor other than carbonic anhydrase.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
19.
Joachim Schofer Rolf Spielmann Florence H. Sheehan Maren Lampe Michael Schlüter Detlef G. Mathey 《The International Journal of Cardiac Imaging》1988,3(4):203-208
In 32 patients with acute myocardial infarction, who had undergone successful intracoronary thrombolysis, the results of regional wall motion measured from contrast cineangiograms 10 to 21 days after thrombolysis were related to the results of thallium single-photon emission computed tomography (SPECT) after intravenous dipyridamole. Wall motion was measured by means of the centerline method, and thallium defect size was estimated by comparing the patient's circumferential profile with that of 20 normals. No correlation was found between ejection fraction or regional wall motion and thallium defect size. The time from symptom onset to thrombolysis was inversely correlated with the degree of hypokinesis (r=–0.51) but not with thallium defect size. In patients treated within 3 hours, hypokinesis was significantly less than in patients treated later (–1.1±0.6 SD vs –2.2±0.8 SD, p<0.01) whereas thallium defect size was not significantly different in both groups. It is concluded that, in patients after thrombolysis, thallium defect size determined by SPECT does not reflect the degree of left ventricular dysfunction. 相似文献
20.
Objective: Aprotinin is widely used in heart surgery for reduction of intraoperative blood loss. But recent reports presenting results from rat aorta experiments claimed that aprotinin selectively impairs endothelium-dependent relaxation (EDR) as well as basal NO availability in concentrations similar to doses routinely used in cardiovascular surgery. An impairment of coronary EDR by aprotinin would be a great danger for any cardiothoracic intervention. We therefore tested the influence of aprotinin in the coronary arteries of a non-rodent species. Methods: Fresh coronary arteries of pigs were obtained from the local slaughterhouse and transported to our laboratory in cold oxygenated Krebs–Henseleit solution. Five-millimeter long rings were consecutively tested with or without aprotinin in concentrations of 500 KIU/ml (n = 7) or 1000 KIU/ml (n = 6) in oxygenated normothermic Krebs–Henseleit solution. PGF2 (10 μmol/l) was used for inducing contraction and substance P (10 nmol/l) for inducing EDR, which was calculated in percentage of the precontraction. Indomethacin (10 μmol/l) was added in all measurements to eliminate the influence of prostaglandins. In additional similar experiments (n = 5), the influence of 1000 KIU/ml aprotinin on the EDR caused by the endothelium-derived hyperpolarizing factor (EDHF) was tested using l-NNA (300 μmol/l) to block all NO formation. Results: The EDR of pig coronaries (82 ± 5% or 80 ± 5% of the precontraction in the control tests before and after aprotinin exposure) was not significantly changed by 500 KIU/ml aprotinin (78 ± 7%). A small, but significant reduction of less than 1/10 of the EDR was induced by 1000 KIU/ml aprotinin (74 ± 5%). After accounting for l-NNA for NO blockage, no aprotinin-related difference remained (59 ± 6% vs 60 ± 6% in controls). Conclusion: For clinically relevant concentrations of aprotinin up to 500 KIU/ml, no significant reduction of the EDR can be found in epicardial coronary arteries of the pig. For higher doses of 1000 KIU/ml, a reduction in NO production seems to be the cause of the small but significant reduction of the EDR by aprotinin. Therefore, danger for impairment of coronary EDR by aprotinin at clinical dosage levels, as suggested by studies on rat aortas, seems to be absent in coronary arteries of a large mammalian model. 相似文献