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41.
During a longitudinal study of vector biology and malaria transmission in western Venezuela, adult mosquitoes were collected by different methods and their efficiency was compared with human landing catches. CDC light traps, a double-net, a calf-baited trap and collection of resting mosquitoes on vegetation were tested. These methods did not prove to be effective substitutes for human landing catches. 相似文献
42.
43.
A conjugative aminoglycoside resistance plasmid pST2 has been isolated from Escherichia coli K-12 14R525, which was mated with a clinical isolate of Salmonella typhimurium S24. A novel resistance gene of aminoglycoside 6'-N-acetyltransferase[AAC(6')] was cloned from plasmid pST2 on a 1,393 kilobase (kb) of SphI-SalI fragment into vector pACYC184 and pUC18. This novel AAC(6') gene in plasmid pST2 acetylated kanamycin, amikacin, dibekacin, tobramycin, gentamicin, netilmicin, and sisomicin. The complete nucleotide sequence of the novel AAC(6') gene and its neighboring sequences were also determined. Minicell experiments detected only one protein of 24.7 kilodaltons (kDa) translated from an open reading frame of the 618 base pairs (bp) gene. 相似文献
44.
Tucker Joan S.; Friedman Howard S.; Tsai Catherine M.; Martin Leslie R. 《Canadian Metallurgical Quarterly》1995,10(1):3
Models of the relations between contact with pets and better health are examined in an archival prospective study using data derived from the longitudinal study initiated by Terman in 1921 (current N?=?343 men, 300 women) . In survival analyses of documented longevity, playing with pets in 1977 (M age?=?67 years) was not associated with mortality risk through 1991 for the total sample nor for those who were unmarried or those who were less satisfied with their human relationships. Playing with pets was not associated with health-prone attributes or healthy behaviors such as personality, social ties, education, and smoking. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
45.
Tsai Jeanne L.; Miao Felicity F.; Seppala Emma; Fung Helene H.; Yeung Dannii Y. 《Canadian Metallurgical Quarterly》2007,92(6):1102
Previous studies have found that in American culture high-arousal positive states (HAP) such as excitement are valued more and low-arousal positive states (LAP) such as calm are valued less than they are in Chinese culture. What specific factors account for these differences? The authors predicted that when people and cultures aimed to influence others (i.e., assert personal needs and change others' behaviors to meet those needs), they would value HAP more and LAP less than when they aimed to adjust to others (i.e., suppress personal needs and change their own behaviors to meet others' needs). They test these predictions in 1 survey and 3 experimental studies. The findings suggest that within and across American and Chinese contexts, differences in ideal affect are due to specific interpersonal goals. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
46.
CF Verkoelen BG van der Boom FH Schr?der JC Romijn 《Canadian Metallurgical Quarterly》1997,15(4):229-235
Large bone flaps for free transfer can be successfully and safely harvested based on the deep branch of the superior gluteal artery. The anatomy is consistent, the vessels are large, and the complications of this technique are minimal. 相似文献
47.
Hyperdynamic circulation of cirrhotic rats: role of substance P and its relationship to nitric oxide
CJ Chu FY Lee SS Wang FY Chang YT Tsai HC Lin MC Hou SL Wu CC Tai SD Lee 《Canadian Metallurgical Quarterly》1997,32(8):841-846
BACKGROUND: It has been suggested that excessive formation of nitric oxide (NO) is responsible for the hyperdynamic circulation observed in portal hypertension. Substance P is a neuropeptide partly cleared by the liver and causes vasodilatation through the activation of the endothelial NO pathway. However, there are no previously published data concerning the plasma level of substance P in cirrhotic rats and its relationship to NO. METHODS: Plasma concentrations of substance P and nitrate/nitrite (an index of NO production) were determined in control rats and cirrhotic rats with or without ascites using an enzyme-linked immununosorbent assay and a colorimetric assay, respectively. In addition, systemic and portal hemodynamics were evaluated by a thermodilution technique and catheterization. RESULTS: Cirrhotic rats with and without ascites had a lower systemic vascular resistance (2.6 +/- 0.2 and 3.9 +/- 0.4 mmHg ml(-1) x min x 100 g body weight, respectively) and higher portal pressure (14.6 +/- 0.6 and 11.3 +/- 1.8 mmHg) than control rats (6.5 +/- 0.3 mmHg x ml(-1) x min x 100 g BW and 6.8 +/- 0.2 mmHg, respectively, P < 0.05), and cirrhotic rats with ascites had the lowest systemic vascular resistance. Plasma levels of nitrate/nitrite progressively increased in relation to the severity of liver dysfunction (control rats, 2.7 +/- 0.5 nmol/ml; cirrhotic rats without ascites, 5.6 +/- 1.3 nmol/ml; cirrhotic rats with ascites, 8.3 +/- 2.2 nmol/ml; P < 0.05). Cirrhotic rats with ascites displayed higher plasma values of substance P (57.7 +/- 5.9 pg/ml) than cirrhotic rats without ascites (37.9 +/- 3.1 pg/ml, P < 0.05) and control rats (30.1 +/- 1.0 pg/ml, P < 0.05). There was no significant difference in plasma substance P values between control rats and cirrhotic rats without ascites (P > 0.05). No correlation was found between plasma levels of substance P and nitrate/nitrite (r = 0.318, P > 0.05). CONCLUSIONS: Excessive formation of NO may be responsible, at least partly, for the hemodynamic derangements in cirrhosis. Although substance P may not participate in the initiation of a hyperdynamic circulation in cirrhosis, it may contribute to the maintenance of the hyperdynamic circulation observed in cirrhotic rats with ascites. 相似文献
48.
CE Alpers CC Tsai KL Hudkins Y Cui L Kuller RE Benveniste JM Ward WR Morton 《Canadian Metallurgical Quarterly》1997,13(5):413-424
Focal and segmental glomerulosclerosis (FSG) with endothelial tubuloreticular inclusions (TRIs) is the typical lesion of human HIV-associated glomerulopathy. Autopsy studies showed the presence of FSG in 3 of 15 macaques dying 15-120 weeks after experimental infection with a simian immunodeficiency virus (SIVMne). Ultrastructural studies generally revealed numerous endothelial TRIs (also present in normals), mesangial expansion, and evidence of mesangial cell injury. One additional animal had a small-vessel polyarteritis with a proliferative and focally crescentic glomerulonephritis; seven animals had mild, multifocal interstitial nephritis. All animals had documented viremia after infection; 14 of 15 developed antibodies to SIV postinoculation. Additional postmortem findings included severe enterocolitis, encephalitis, and opportunistic infections. In contrast, autopsy studies of macaques infected with a type D simian retrovirus (SAIDS-D/Washington, SRV-2) for similar periods of time (n = 40) showed no evidence of FSG. One SRV-infected animal had a mild proliferative glomerulonephritis. These studies indicate SIV-infected primates may provide a relevant model for study of human HIV-associated nephropathy. They also indicate the variable pathology that can be seen in primate infections of distinct retrovirus types, each of which produces a simian immunodeficiency state that resembles human AIDS. 相似文献
49.
Sperm from the American lobster (Homarus americanus) are normally nonmotile. However, during fertilization, the sperm undergo a calcium-dependent acrosome reaction that propels them forward about 18 microns. The reaction occurs in two phases, eversion and ejection, which take place too quickly to permit analysis by direct observation. The purposes of this study were to examine the structural changes occurring in sperm during the normal acrosome reaction and to determine the rate of the reaction using video microscopy. The reaction was induced in vitro by ionophore A23187 and recorded using a video system attached to a Nikon Nomarski interference microscope. Videotapes were played back frame by frame (30 frames/sec), and images of reactions from 10 sperm were analyzed. The acrosome reaction, including the eversion of the acrosomal vesicle and ejection of the subacrosomal material and nucleus, can be divided into 4 steps: (1) expansion of the apical cap followed by expansion of the remainder of the acrosomal cylinder; expansion of the cylinder begins at its apical end and proceeds toward its base, (2) eversion of the apical half of the acrosomal vesicle and initial contraction of the apical cap, (3) eversion of the basal half of the acrosomal vesicle, continued contraction of the apical cap, and ejection of the subacrosomal material and nucleus, and (4) final contraction of the apical cap and ejection of the acrosomal filament. During steps 2, 3, and 4, the mean forward movement of sperm is 12.7, 3.9, and 1.1 microns, respectively.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
50.
The prevalence of preferential nasal breathing was studied in an awake adult population. One hundred and ninety-four people consented to gentle manual compression of the nostrils. They were advised to 'breathe in and out', but no further information regarding breathing was given to avoid influencing the patient. One hundred and eighty patients (92.8%) commenced immediate regular relaxed breathing. Fourteen patients (7.2%) had difficulty with oral breathing which ranged from irregular mouth breathing associated with distress to no spontaneous respiration. The prevalence of preferential nasal breathing was strongly associated with increasing age (chi 2 for trend, P = 0.007). In addition, a weakly significant association was demonstrated between a history of asthma and this phenomenon (P = 0.047). These findings suggest a tendency for the elderly person to revert to the infant pattern of obligate nasal breathing. Physicians should be aware of this possibility in the elderly patient, especially prior to any procedure which may induce nasal obstruction. 相似文献