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排序方式: 共有754条查询结果,搜索用时 8 毫秒
141.
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143.
P. DE LA SALMONIÈRE M. JANIER J. GILQUIN A. CARLOTTI L. SUTTON † V. LEBLOND† F. DANIEL 《Clinical and experimental dermatology》1994,19(6):505-506
Lymphoid neoplasia is now well known to occur in patients with human immunodeficiency virus (HIV) infection but the first case of acute monocytic leukaemia in an HIV-seropositive man has been only recently described. We report the case of an HIV-infected patient who simultaneously developed skin lesions of acute monocytic leukaemia and chicken pox. We suggest that HIV may produce a malignant transformation of monocytic cells. 相似文献
144.
145.
The pulse-sequence equations for spin-echo magnetic resonance imaging were used to determine interpulse delay times that give the highest signal-to-noise ratio from a single tissue. This theoretical result was then verified experimentally using 1-, 2-, and 5-mM/l copper sulfate solutions imaged on a 0.15-T resistive system. Theoretical analysis determined the spin-echo interpulse delay times that maximize the signal-to-noise ratio from a single tissue as TEopt = TEmin, the minimum echo delay time permitted by the system, and, to a good approximation, TRopt = 1.27 T1 + 1.90 TEmin, with T1 the longitudinal magnetic relaxation time of the tissue. Phantom measurements of the signal-to-noise ratio in a typical imaging system confirmed the theoretically determined TRopt values to within 7%. 相似文献
146.
Determination of sibship in any two persons 总被引:4,自引:0,他引:4
BACKGROUND: Parentage testing laboratories may be asked to provide genetic evidence that two persons are or are not related, when no other relatives are available for study. Simple methods using autosomal, codominant, unlinked genetic systems can determine if two people are blood relatives (e.g., siblings). STUDY DESIGN AND METHODS: The odds ratios (full sibship index) of true sibling pairs were determined from two-child paternity cases and compared with regionally and racially matched control pairs of unrelated children. The sharing of two, one, or no alleles was observed in pairs of children at three independent, polymorphic VNTR (variable number of tandem repeat) sequences loci. The sibship index was calculated as (the chance that an observation would occur if two children were siblings) divided by (the chance that it would occur if the two were unrelated). Sibship indices and the frequencies of shared alleles were determined for 20 sibling pairs and 20 control pairs. RESULTS: Sibship index values were less than 1 in all 20 pairs of unrelated children. Sibship index values were greater than 100 in nine pairs of siblings (45%), between 10 and 100 in five pairs (25%), between 1 and 10 in four pairs (20%), and less than 1 in two pairs (10%). Siblings shared two alleles in 17 of 60 observations (28.3%); controls shared two alleles in 0 of 60 observations (0%). CONCLUSION: The sharing of one allele and the sharing of no alleles at a polymorphic locus of high heterozygosity provide limited information for and against sibship, respectively. The sharing of two alleles produces strong evidence favoring sibship. In a given case, the study of more than three polymorphic loci of high heterozygosity may be needed to develop the evidence that two people are siblings. The general logic and methods used for siblings apply to kinship analyses of other two-person pedigrees. 相似文献
147.
Introduction: Temporary GES (tempGES) can improve both gastric emptying and symptoms in post-surgical gastroparesis (PS-GP). (SSAT 2004). Long-term effects on GI symptoms and gastric emptying are unknown. Since many PS-GP patients have non-delayed emptying, the long-term effect on baseline normal or rapid emptying is also unknown.
Patients: 36 pts (6 M, 30 F, mean age 42 years) with post-surgical: Bilroth I ( n = 11), Bilroth II ( n = 4), other gastric surgery ( n = 21) disordered gastric emptying were evaluated.
Methods: GI symptoms (vomiting = V, Total = TSS), and solid meal gastric emptying (GET) at 1 and 4 h, were compared at baseline (Base), after temporary (tempGES) and permanent (permGES) gastric electrical stimulation as previously described (NGM, 2004; 16: 635.) Long-term follow-up for permanent GES ranged from 6 month to 10 years. Results were compared by t-tests, and are reported as means ± SEM.
Results: 29 of the 36 patients were able to tolerate food for baseline quantitative gastric emptying testing. 20 patients had delayed and 9 patients had non-delayed gastric emptying, with 7/9 being rapid. With both tempGES and permGES, GI symptoms improved (p < 0.05). Both tempGES and permGES showed accelerated GET for delayed patients and generally slowed GET for non-delayed (p < 0.05 for 1 h values). See tables below.
Conclusions: In a large group of post-surgical GP patients, temporary and permanent gastrointestinal electrical stimulation improved GI symptoms independent of gastric emptying and for a prolonged time. GES improves symptoms independent of baseline gastric emptying, and improves GET dependent on the baseline gastric emptying.
Patients: 36 pts (6 M, 30 F, mean age 42 years) with post-surgical: Bilroth I ( n = 11), Bilroth II ( n = 4), other gastric surgery ( n = 21) disordered gastric emptying were evaluated.
Methods: GI symptoms (vomiting = V, Total = TSS), and solid meal gastric emptying (GET) at 1 and 4 h, were compared at baseline (Base), after temporary (tempGES) and permanent (permGES) gastric electrical stimulation as previously described (NGM, 2004; 16: 635.) Long-term follow-up for permanent GES ranged from 6 month to 10 years. Results were compared by t-tests, and are reported as means ± SEM.
Results: 29 of the 36 patients were able to tolerate food for baseline quantitative gastric emptying testing. 20 patients had delayed and 9 patients had non-delayed gastric emptying, with 7/9 being rapid. With both tempGES and permGES, GI symptoms improved (p < 0.05). Both tempGES and permGES showed accelerated GET for delayed patients and generally slowed GET for non-delayed (p < 0.05 for 1 h values). See tables below.
Conclusions: In a large group of post-surgical GP patients, temporary and permanent gastrointestinal electrical stimulation improved GI symptoms independent of gastric emptying and for a prolonged time. GES improves symptoms independent of baseline gastric emptying, and improves GET dependent on the baseline gastric emptying.
148.
Benzimra RE; Antao AJ; Donovan KL; Williams AJ 《QJM : monthly journal of the Association of Physicians》1998,91(6):417-422
Haemolytic uraemic syndrome (HUS) and thrombotic thrombocytopenic purpura
(TTP) are conditions in which thrombocytopenia and microangiopathic
haemolytic anaemia are associated with organ damage due to thrombotic
microangiopathy (TMA). The prognosis for adults with HUS is variable, with
some patients presenting with an acute illness from which a full recovery
is made, whilst others develop irreversible renal failure. Evidence of
retinal ischaemia was noted on presentation in a normotensive patient with
irreversible renal failure due to HUS. This study examined prospectively
the optic fundi of all patients who subsequently presented to a single
adult renal unit (catchment population approximately 700,000) with HUS.
Eleven patients presented with HUS over 12 years (1985-1997). Six patients
with irreversible renal failure had retinal abnormalities either at the
time or within a few days of initial presentation. The other five patients
whose renal function recovered did not develop retinal changes during the
course of their illness. Retinal ischaemia associated with TMA is a poor
prognostic sign in adults with HUS.
相似文献
149.
JOSEPH PALADINO CHRISTOPHE THURIEAU ANGELA D. MORRIS NATHALIE KUCHARCZYK NOUREDDINE ROUISSI DOMENICO REGOLI JEAN-LUC FAUCHRE 《Chemical biology & drug design》1993,42(3):284-293
A series of pseudopeptide analogs of the substance P-like hexapeptide Ava-Phe-Phe-Gly-Leu-Met-NH2 was produced by Nα-protection, introduction of the thiomethylene bond, of d - and non-proteinogenic amino acids, and alteration of the side chain of tryptophan. Synthesis of the pseudopeptides on a solid phase was successfully improved by direct formation of the CH2—S bond on the resin. However, while thiomethylene formation between leucine and norleucine led to the expected SS diastereoisomer, the major product of the similar coupling between two phenylalanines was the SR isomer. An improved resistance of the analogs to proteolysis was observed, which could be related to the structural changes. Interestingly, these modifications led to three water-soluble and potent neurokinin antagonists on classical in vitro bioassays. 相似文献
150.