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1.
Membrane fluidity and adrenergic receptor binding were studied in platelets of depressed patients before and during treatment with desmethylimipramine to investigate the relationship between the alpha 2-adrenergic receptor and its membrane environment in depression. Most samples came from a previous study in which we observed higher 3H-para-aminoclonidine (3H-PAC) binding in platelets from depressed patients compared to healthy subjects. Fluidity was measured by steady state diphenylhexatriene (DPH) anisotropy in both purified plasma membranes and in intracellular membrane preparations from platelets. No differences were observed in DPH membrane fluidity, per se, indicating that fluidity changes probably do not underlie either the increased alpha 2-adrenergic receptor binding in depression or the normalization of binding during treatment. However, lower intracellular membrane fluidity was correlated with higher binding to 3H-PAC site-1 in healthy subjects, but not in depressed patients. Thus, during depression there may be a disruption in the normal relationship between the adrenergic receptor and its membrane environment. 相似文献
2.
The efficacy of two dry cow treatment (DCT) regimens for subclinical Staphylococcus aureus mastitis was evaluated in naturally infected dairy cows. At dry‐off, cows were assigned to two treatment groups by randomized blocks on the basis of parity and somatic cell count (SCC). Two antibiotic DCT regimens were used, namely: (1) a single intramammary infusion containing sodium nafcillin, procaine benzylpenicillin and dihydrostreptomycin; and (2) systemic cefquinome administered intramuscularly, twice at a 24‐h interval. In the intramammary (IMM) treatment group, the S. aureus intramammary infection (IMI) rate was reduced from 40% (56/140 quarters) before dry‐off to 20% (28/140) after calving. Seventy per cent (39/56) of the S. aureus‐positive quarters were negative after calving, and 13% (11/84) of the negative quarters were positive after calving. In the systemic treatment group, the S. aureus IMI rate increased from 39% (29/74 quarters) before dry‐off to 55% (41/74) after calving. Twenty‐eight per cent (8/29) of the S. aureus‐positive quarters were negative after calving and 45% (20/45) of the negative quarters were positive after calving. The odds ratio of an S. aureus‐positive quarter being negative after calving in the IMM group relative to the systemic therapy group was 44.6 (95% confidence interval = 2.1–909.1, P < 0.01). Parity, quarter, milk SCC and N‐acetyl‐β‐D‐glucosaminidase were tested in the model, and were found to have no significant effect on S. aureus cure rates or new IMI rates. The IMM treatment resulted in a higher cure rate compared with that observed in previous studies. The very low cure rate after systemic cefquinome treatment was comparable to the spontaneous cure rate observed in untreated controls in previous studies. The unfavourable results of the cefquinome systemic DCT might reflect inadequate pharmacokinetic properties of the drug regarding poor udder penetration in subclinical mastitis and short antimicrobial effect compared with the IMM treatment. 相似文献
3.
To assess its reliability as a marker of cardiomegaly in elderly patients, we compared a clinical assessment of heart size with that calculated from chest radiography. In 100 hospitalized subjects of median age 78 years, the apex beat was palpable in only 35% and its palpability declined with increasing age. Even when palpable, the apex beat had low specificity (74%) and sensitivity (69%) as a marker of cardiomegaly and its positive predictive value (69%) and negative predictive value (74%) were poor. The clinical assessment of heart size in elderly hospitalized patients should be interpreted with caution. 相似文献
4.
Martin C Saran R Leavey S Swartz R 《ASAIO journal (American Society for Artificial Internal Organs : 1992)》2002,48(6):640-644
Continuous renal replacement therapy (CRRT), such as continuous venovenous hemofiltration, has theoretical advantages over intermittent hemodialysis (IHD) that are related to cardiorespiratory stability, metabolic control, and fluid balance allowing nutritional supplementation. However, retrospective and controlled studies fail to show these advantages because of comorbidity associated with triage to CRRT. To compare outcomes using IHD versus CRRT, we applied published risk stratification models (Cleveland Clinic Foundation, Lohr index, and APACHE II) to the 349 patients with acute renal failure requiring renal replacement therapy at University of Michigan over the 2 year period including 1995 and 1996. The Cleveland Clinic Foundation model best predicted overall mortality, but our CRRT patients had excess, unpredicted mortality that was particularly prominent in the lower risk categories. The Lohr clinical score predicted mortality less accurately but also was associated with higher, unpredicted mortality at lower risk scores among the CRRT patients. APACHE II scores did not predict mortality very well among IHD, CRRT, or the combined group of patients. We conclude that the need for CRRT itself predicts mortality over and above that included in published risk models. Either CRRT is associated with some unidentified morbidity (e.g., treatment associated infection) or, more likely, triage to CRRT is associated with as yet unspecified comorbidity not detected in existing risk stratification schemes. It will be important to address these issues in any future studies evaluating outcome or comparing renal replacement therapy modalities among patients with severe acute renal failure. 相似文献
5.
Selection by phage display of llama conventional V(H) fragments with heavy chain antibody V(H)H properties 总被引:4,自引:0,他引:4
Tanha J Dubuc G Hirama T Narang SA MacKenzie CR 《Journal of immunological methods》2002,263(1-2):97-109
A llama single domain antibody (dAb) library designed and constructed to contain only heavy chain antibody variable domains (V(H)Hs) also contained a substantial number of typical conventional antibody heavy chain variable sequences (V(H)s). Panning the library against two carbohydrate-specific antibodies yielded anti-idiotypic dAbs and enriched solely for sequences from the V(H) subpopulation of the library. The conventional antibody origin of these V(H)s was confirmed by using oligonucleotide probes, specific for the enriched V(H)s, to identify the parental sequences in the message employed in library construction. Surprisingly, these V(H) dAbs, which are produced in high yield in Escherichia coli, are highly soluble, have excellent temperature stability profiles and do not display any aggregation tendencies. The very close similarity of these molecules to human V(H)s makes them potentially very useful as therapeutic dAbs. 相似文献
6.
Pulmonary tuberculosis among contacts of patients with tuberculosis in an urban Indian population. 总被引:1,自引:0,他引:1
R A Kumar M Saran B L Verma R N Srivastava 《Journal of epidemiology and community health》1984,38(3):253-258
The study was conducted among 1810 contacts of 50 index "cases"/"suspects" of pulmonary tuberculosis including 312 household and 1498 neighbourhood contacts in the Jhansi city of Uttar Pradesh. The overall prevalence of radiologically active and bacteriologically confirmed tuberculosis was 2.9% and 1.1%. The prevalence rates of radiologically active and bacteriologically confirmed disease, although comparatively high in both the contact groups, were significantly higher in household (5.4% and 2.6%) than in neighbourhood contacts (2.3% and 0.8%). Significant differences in distribution of secondary cases among clusters were observed. Although higher prevalence rates were found in contacts of sputum positive source than in contacts of sputum negative source in both the contact groups, the statistical difference was observed to be insignificant. Case yield among contact symptomatics was 80.0% (30.8% cases and 49.2% suspects). 相似文献
7.
The purpose of this study was to investigate the ultrastructural changes taking place in the testicular tissue of adult male Wistar rats following exposure to cigarette smoke. Twenty rats were exposed to smoke in a smoking machine for 2 h daily for 60 days; 10 control rats were placed in the machine for the same amount of time but were exposed to room air. After ether anesthesia and dissection of the animals, the testes were removed and fixed in 2.5% glutaraldehyde. The sections were examined under a transmission electron microscope. Evident degeneration and dissociation of the spermatogenetic cells were common findings. Basal lamina of the tubuli seminiferi contorti was thickened and significantly irregular. Cigarette smoke inhalation damaged the seminiferous epithelium. The primary spermatocytes as well as Sertoli cells appeared to be targets for the smoke. The results indicated that cigarette smoke inhalation could cause specific lesions in the development of spermatozoon, and it might be either directly or indirectly toxic to spermatogenesis. 相似文献
8.
Effect of genetic modification of acute inflammatory responsiveness on tumorigenesis in the mouse 总被引:1,自引:3,他引:1
9.
We report a case of unilateral cataract with a posterior located central opacity greater than 3 mm in diameter, which resolved without surgical intervention in an otherwise healthy child. 相似文献
10.
Mohammad Mozafar Khashayar Atqiaee Hamidreza Haghighatkhah Morteza Sanei Taheri Ali Tabatabaey Saran Lotfollahzadeh 《Lasers in medical science》2014,29(2):765-771
Endovenous laser therapy (EVLT) for greater saphenous vein (GSV) insufficiency is a relatively new method of treatment only recently made available in Iran. This is the first long-term randomized trial comparing EVLT with high ligation of saphenous vein (HLS) in the Iranian population. Sixty-five patients met the inclusion criteria and were divided into homogenous treatment groups of EVLT (n?=?30) or HLS (n?=?35). Clinical severity, etiology, anatomy, pathophysiology (CEAP) classification and Aberdeen Varicose Vein Symptom Severity Scores (AVSS) were used to determine disease severity and symptoms before and after the procedure in both groups. Outcome was measured by the rate of recurrence as shown in Doppler ultrasonography evaluation. Follow-up was conducted 1 week and 3, 6, 12, and 18 months after the intervention. The occlusion rate of GSV was similar in both groups (93.6 % for EVLT, 88.3 for HLS) at 18 months of follow-up. The median CEAP score showed a dramatic decrease in both groups after 1 week which was sustained for the rest of the study. The Aberdeen Varicose Vein Symptom Severity score was significantly lower in the EVLT group at 12 and 18 months of follow-up. There was no significant difference in patient satisfaction in both groups. Our findings show that EVLT may offer a better long-term relief of symptoms. This, alongside its better cosmetic outcome, and less invasive anesthesia requirements may make it the favorable choice for treatment of GSV insufficiency. 相似文献