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41.
Tobias JD Holcomb GW Brock JW Morgan WM O'Dell N Lowe S Rasmussen GE 《The American journal of anesthesiology》1995,22(4):193-197
The authors prospectively evaluated the efficacy of caudal epidural block versus local infiltration combined with ilioinguinal/iliohypogastric block for analgesia after inguinal herniorrhaphy with laparoscopic inspection of the peritoneum. During standardized anesthetic care, 24 children were randomized to Group I (caudal epidural block with 1.2 mL/kg of 0.25% bupivacaine) or to Group II (local infiltration with an ilioinguinal/iliohypogastric block). Postoperative pain scores were significantly lower at all four evaluation points in Group I than in Group II. Patients in Group I had a significantly decreased requirement for supplemental intravenous fentanyl. Intra-operative requirements for isoflurane were decreased in Group I. The expired concentration of isoflurane was 0.4 +/- 0.1 (mean +/- SEM) in Group I and 1.5 +/- 0.3 in Group II. Time to extubation was 3.8 +/- 0.5 minutes in Group I and 8.2 +/- 1.1 minutes in Group II. The time from arrival in the postanesthesia care unit until discharge home was 113 +/- 3 minutes in Group I and 152 +/- 11 minutes in Group II. Caudal epidural block was more effective than local infiltration in controlling pain after herniorrhaphy with laparoscopy in children and resulted in earlier discharge home. 相似文献
42.
A random sample of students (N = 3,655) in Grades 7, 9, and 11 from 55 schools in Queensland (Australia) were surveyed about their sun protection knowledge, attitudes, and behaviors. An aggregate sun protection behavior index (SPBI) was developed from self-reported behaviors on a school day and a weekend day. Repeated measures regression analyses revealed that negative views of sun protection measures were associated with low scores on the SPBI, an association that was strongest among older students and in larger schools. Low perceived parental sun protective behaviors were associated with low SPBI ratings, and this association was greatest in small schools and on Saturdays. Older students had lower SPBI ratings, but their scores increased on Saturdays. Gender did not appear to be independently related to the SPBI after adjustment for the other variables. These findings reinforce the need for adolescent sun protection programs to address the complex interactions among psychological, social, and environmental factors that influence different subgroups of the student population. 相似文献
43.
The objective of this review is to evaluate the measurement tools currently used in the study of eccentric contraction-induced muscle injury, with emphasis on their usefulness for quantifying the magnitude and duration of the injury and as indicators of muscle functional deficits. In studies in humans, it was concluded that measurements of maximal voluntary contraction torque and range of motion provide the best methods for quantifying muscle injury. Similarly, in animal studies, the in vitro measurement of electrically elicited force under isometric conditions was considered to be the best of the measurement tools currently in use. For future studies, more effort should be put into measuring other contractile parameters (e.g. force/torque-velocity and force/torque-length relationships maximal shortening velocity and fatigue susceptibility) that may reflect injury-induced functional impairments. The use of histology, ratings of soreness and the measurement of blood or bath levels of myofibre proteins should be discouraged for purposes of quantifying muscle injury and/or functional impairment. 相似文献
44.
Lowe G Droz AS Vilaivan T Weaver GW Tweedale L Pratt JM Rock P Yardley V Croft SL 《Journal of medicinal chemistry》1999,42(6):999-1006
A range of (2,2':6',2'-terpyridine)platinum(II) complexes are shown to possess antiprotozoal activity in vitro against Leishmania donovani, Trypanosoma cruzi, and Trypanosoma brucei,the causative organisms of tropical diseases leishmaniasis and trypanosomiasis. The best compounds caused 100% and 78% inhibition of growth of the intracellular amastigote forms of L. donovani and T. cruzi, respectively, at a concentration of 1 microM and 100% inhibition of growth of the bloodstream trypomastigote forms of T. brucei at a concentration of 0.03 microM. The results obtained with complexes in which the fourth ligand to platinum(II) is capable of being substituted with a substitution inert hydroxyethanethiolate complex are compared. The ammine complexes show high antiprotozoal activity suggesting that the trans influence of the 2,2':6',2'-terpyridine ligand has a profound effect on the ease of displacement of the fourth ligand in (2,2':6',2' -terpyridine)platinum(II) complexes, although nonbonded interaction between the ammine ligand and the 6 and 6' ' hydrogens probably also weakens the ligation to Pt(II). 相似文献
45.
Devere White RW Deitch AD Tesluk H Blumensteinj B Lowe BA Sagalowsky AI Smith JA Schellhammer PF Stanisic TH Grossman HB Messing E Crissman JD Crawford ED 《Urologic oncology》1996,2(1):27-34
While 80% of transitional cell carcinomas (TCC) present as Ta Tl lesions, they account for only 15% of deaths caused by TCC. We have evaluated the ability of DNA ploidy analysis to predict outcome in 228 patients with Ta Tl TCC. All patients were judged to be at increased risk for tumor recurrence due to having two occurrences of Stage TI tumor within 56 weeks, or three or more tumors presenting simultaneously within 16 weeks of registration. Concurrent carcinoma in situ was acceptable. All patients were treated with either bacillus Calmette Guerin (BCG) immunotherapy or mitomycin-C (MMC) intravesical chemotherapy. Patients with nondiploid tumors had higher hazard rates for both tumor progression and death (p = 0.007 and p = 0.016, respectively); however, the prognostic information of DNA ploidy was not additive to tumor grade. 相似文献
46.
J M Enoch V Lakshminarayanan A Itzhaki B M Khamar K Landau T Lowe T Surendran J Comerford 《Optometry and vision science》1991,68(10):807-812
Three visual manifestations of Gilles de la Tourette syndrome (TS), a neuropsychiatric disorder, have been previously reported. In this paper we report anomalies in the measured kinetic paracentral visual field of TS patients and their family members. We found that 96% of TS patients exhibited paracentral kinetic visual field defects (nasal and temporal steps, enlargement, "ringing," and/or baring of the blind spot). Ninety-three percent of fathers of TS children and, surprisingly, about 80% of mothers exhibit these characteristic visual field anomalies. Sample data and examples of family studies are reported. 相似文献
47.
C A Toomer C H Schwalbe N S Ringan P A Lambert P R Lowe V J Lee 《Journal of medicinal chemistry》1991,34(7):1944-1947
Tazobactam (3, C10H12N4O5S) is an effective inhibitor of bacterial beta-lactamases. It crystallizes with unit cell dimensions a = 10.230 (2) A, b = 14.396 (2) A, and c = 17.291 (2) A in space group P2(1)2(1)2(1). Compared to the related inhibitor sulbactam (2), which lacks the triazole ring, crystalline tazobactam exhibits very similar beta-lactam geometry and the same S(1) envelope conformation of the thiazolidine ring. However, in both independent molecules of 3 a triazole ring nitrogen atom accepts an intermolecular hydrogen bond; similar interaction by this moiety of 3 with a hydrogen-bond donor on the enzyme, which is impossible for 2, could account for its enhanced inhibitory power. Semiempirical molecular orbital calculations show pronounced negative potential there. Molecular mechanics supports the hypothesis that the carboxyl group can rotate freely and the triazole ring can "flip". 相似文献
48.
Flow cytometry is a high-precision technique for rapid analysis and sorting of cells and particles. In theory, it can be used to measure any cell constituent, provided that a fluorescent tracer is available that reacts specifically and stoichiometrically with that constituent. The technique provides statistical accuracy, reproducibility, and sensitivity and allows simultaneous measurement of several constituents on a cell-to-cell basis. The main drawback of flow cytometry is the lack of visual control and structural information in solid tissues. Careful sample preparation, quality control of all staining and instrumentation procedures, and the use of immunohistologic or cytologic controls are essential for high-quality flow cytometric analysis. The technique has been used successfully for simultaneous measurement of DNA and tumor-associated antigens, oncogene products, proliferation markers, and markers for multidrug resistance in cultured cell lines and in cell suspensions prepared from solid tumors and cervical smears. Flow cytometry has the potential to play an important role in the study of carcinogenesis. With an appropriate panel of monoclonal antibodies, the technique can be used for screening, "biochemical" diagnosis of neoplasia, and rapid drug, hormone, and radiotherapy sensitivity tests. 相似文献
49.
T. Peter Lowe Rey C. Stendell 《Archives of environmental contamination and toxicology》1991,20(4):519-522
American kestrels (Falco sparverius) were fed diets containing 3 g/g Aroclor® 1 1248 or control diets from mid-January until July. Eggs were removed from first clutches 2 to 4 days after laying ceased and shell thickness and shell dimensions were measured. Contents of the third egg of each clutch, the carcasses of all adults that received Aroclor® 1248 and of three males and three females that received the control diet were analyzed for DDE, Aroclors® 1248, 1254 and 1260, and dieldrin. Concentrations of PCBs, DDE and dieldrin were significantly higher (P < 0.03) in eggs and carcasses from treated adults than in controls. Shell thickness and shell thickness index of eggs from treated adults were reduced 5.0% (P < 0.0001) and 4.8% (P < 0.0001), respectively, from those of controls. 相似文献
50.
Fannon D Chitnis X Doku V Tennakoon L O'Ceallaigh S Soni W Sumich A Lowe J Santamaria M Sharma T 《The American journal of psychiatry》2000,157(11):1829-1834
OBJECTIVE: Structural magnetic resonance imaging (MRI) studies that focus on first-episode psychosis avoid some common confounds, such as chronicity of illness, treatment effects, and long-term substance abuse. However, such studies may select subjects with poor short-term treatment response or outcome. In this study, the authors focus on structural brain abnormalities in never or minimally treated patients who underwent MRI scanning early in their first episode of psychosis. METHOD: The authors examined 37 patients (13 medication naive, 24 previously treated) who were experiencing their first episode of psychosis; the mean duration of symptoms was short (31 weeks). These patients were comparable in age, gender, handedness, ethnicity, and parental socioeconomic status to a group of 25 healthy comparison subjects. A three-dimensional, inversion recovery prepared, fast spoiled gradient/recall in the steady state scan of the whole brain that used 1.5-mm contiguous sections was performed to acquire a T(1)-weighted data set. Human ratings of volumetric measurement of brain structures were performed with stereological techniques on three-dimensional reconstructed MRIs. RESULTS: The patient group had significant deficits in cortical gray matter, temporal lobe gray matter, and whole brain volume as well as significant enlargement of the lateral and third ventricles. Structural deviations were found in both treatment-naive and minimally treated subjects. No relationships were found between any brain matter volumes and positive or negative symptoms. CONCLUSIONS: Structural brain abnormalities were distributed throughout the cortex with particular decrement evident in gray matter. This feature is consistent with altered cell structure and disturbed neuronal connectivity, which accounts for the functional abnormality of psychosis. 相似文献