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In this paper a method of semiquantitative cysteine determination is presented, which is based on the formation of a red cysteine-Na-nitroprusside salt. The method is a suitable rapid test for checking the process of ascorbic acid therapy in cystinuria and cystine urolithiasis patients. It guarantees acceptable reproducibility of values and can be easily carried out in every clinicochemical laboratory. With the K2CO3/nitroprusside test described and an additional cystine rapid test (Ni2+/S2O4(2-) tablet reagency) a separate semiquantitative differentiation of cysteine and cystine in fresh (!) urine is possible.  相似文献   
103.
Social stress associated with the formation of a new group of rhesus monkeys resulted in increased basal cortisol secretion and significant decreases in immunological parameters. Eight adult female rhesus monkeys, all of which had been raised in social groups, but with no common social history, were simultaneously introduced into an outdoor enclosure along with an adult male. Behavioral data were collected during the introduction and over 9 weeks thereafter. Blood samples were collected prior to and at intervals for 9 weeks following formation. The establishment of a dominance hierarchy, apparent within 48 h, was accomplished with no serious fighting and a complete absence of wounding or trauma. Overall, the group showed a significant increase in cortisol and a significant decrease in the absolute number of total lymphocytes and CD4+ and CD8+ T cells at 24 h postformation, but not thereafter. However, when partitioned into high and low dominance rank, differences in CD4+ and CD8+ T cells were evident for up to 9 weeks with low ranking subjects showing significantly lower values. The housing condition of the subjects immediately prior to introduction, either indoors in individual caging or outdoors in social groups, may have influenced behavior, rank acquisition, and possibly differences in immune parameters. These data demonstrate that social group formation is a potent psychosocial stressor in primates, since stress-sensitive changes were observed in the absence of serious aggression and wounding.  相似文献   
104.
Taxonomic classification of hepatitis A virus   总被引:13,自引:0,他引:13  
Sufficient data have accumulated to permit the ICTV Ad Hoc Study Group on the Taxonomy of Hepatitis Viruses to recognize hepatitis A virus as a picornavirus. Within the family Picornaviridae, hepatitis A virus closely resembles members of the genus Enterovirus.  相似文献   
105.
The aim of this study was to evaluate the results of open reduction and internal fixation through the extended lateral approach (ELA) in displaced intra-articular calcaneal fractures and to determine whether this approach should remain part of standard therapy. This retrospective cohort study included 60 patients with 64 displaced intra-articular calcaneal fractures who underwent surgical treatment through the ELA. Outcome measures were the visual analog scale foot and ankle (VAS FA), the American Orthopedic Foot and Ankle Society (AOFAS) score, surgical site infections (SSIs), and reoperations. We determined the AOFAS score for 40 patients with 42 fractures, and 42 patients with 44 fractures completed the VAS FA questionnaire. The mean VAS FA score was 61.0 ± 23.4 and the median AOFAS score was 83 (range 33 to 100), with 55% good to excellent scores. We found 10.9% superficial SSIs successfully treated with antibiotics. In 4.7% of patients a deep SSI was diagnosed, wherefore premature implant removal was necessary. Patients with an SSI did not have significantly lower VAS FA or AOFAS scores than did patients without an SSI (p = .318 and p = .766, respectively). Implant removal in absence of SSIs was necessary in 17 patients because of pain, and 3 patients needed secondary arthrodesis because of persistent pain. We concluded that the ELA proved to be a safe procedure, and moreover the most common complications did not influence the long-term outcomes of patients. However, recent literature demonstrates that less invasive techniques seem to exceed the ELA with respect to wound complications.  相似文献   
106.
N,N'-Dialkyl-1,2-bis(2,6-dichloro-4-hydroxyphenyl)ethylenediamines show structural analogy with estrogens and selective estrogen receptor modulators. Because the vasodilator properties of these compounds are unknown, we investigated their potential to relax porcine coronary arteries and determined the mechanism(s) of relaxation. Isolated porcine coronary arterial rings were suspended in organ chambers, precontracted with KCl (30 mM), and the relaxant response was determined by measurement of changes in isometric force. Dependent on the chemical structure, the drugs induced concentration-dependent relaxation in rings with and without endothelium. N,N'-Dipropyl-1,2-bis(2,6-dichloro-4-hydroxyphenyl)ethylenediamine (8) was most potent and showed a 12- to 15-fold higher vasodilatory effect than 17beta-estradiol (E2). The vasorelaxation was independent of endothelium. Calcium concentration-dependent contractions in high-potassium depolarizing medium were insurmountably inhibited by 8. The effect of the L-type Ca2+ channel activator (S)-(-)-Bay K 8644 [(S)-(-)-1,4-dihydro-2,6-dimethyl-5-nitro-4-[2-(trifluoromethyl)phenyl]-3-pyridine-carboxylic acid methyl ester], which induced a leftward shift of Ca2+ contraction, was blocked by 8. The relaxant response to 8 was unaffected by the estrogen receptor antagonist ICI 182,780 (7alpha-[9-[(4,4,5,5,5-pentafluoropentyl]-sulfinyl]nonyl]-estra-1,3,5(10)-triene-3,17beta-diol) and K+ channel blockers, i.e., TEA, glibenclamide, and 4-aminopyridine. Furthermore, the vasodilatory effect of 8 was unaffected by the adenylyl cyclase inhibitor SQ 22536 [9-(tetrahydro-2-furanyl)-9H-purin-6-amine], the guanylyl cyclase inhibitor ODQ [1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one], the protein kinase A inhibitor KT 5720 [(9S,10S,12R)-2,3,9,10,11,12-hexahydro-10-hydroxy-9-methyl-1-oxo-9,12-epoxy-1H-diindolo[1,2,3-fg: 3',2',1'-kl]pyrrolo[3,4-i][1,6]benzodiazocine-10-carboxylic acid hexyl ester], the protein kinase G inhibitor KT 5823 [(9S,10R,12R)-2,3,9,10,11,12-hexahydro-10-methoxy-2,9-dimethyl-1-oxo-9,12-epoxy-1H-diindolo[1,2,3-fg:3',2',1'-kl]pyrrolo[3,4-i][1,6]benzodiazocine-10-carboxylic acid methyl ester], and the p38 mitogen-activated protein kinase (MAPK) inhibitor SB 203580 [4-(4-fluorophenyl)-2-(4-methylsulfinylphenyl)-5-(4-pyridyl)-1H-imidazole]. Western blot analysis demonstrated that 8, unlike E2, raloxifene, and tamoxifen, failed to stimulate p38 MAPK. It is concluded that N,N'-dipropyl-1,2-bis(2,6-dichloro-4-hydroxyphenyl)ethylenediamine induces endothelium-independent relaxation of coronary arteries; the mechanism apparently involves inhibition of L-type Ca2+ channels. The drug may be protective against cardiovascular diseases.  相似文献   
107.
The polypeptides of hepatitis A virus.   总被引:8,自引:0,他引:8  
Hepatitis A virus was purified from fecal specimens obtained from 3 patients with naturally acquired hepatitis A, by a process of differential centrifugation, chloroform extraction, column chromatography, and isopycnic ultracentrifugation. Analysis of purified virus by discontinuous SDS-PAGE revealed three major polypeptides with molecular weights of 34,000, 25,500, and 23,000 daltons. These polypeptides appear to be specific for hepatitis A virus and have similar molecular weights to three of the four major polypeptides reported for members of the genus Enterovirus within the family Picornaviridae.  相似文献   
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