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排序方式: 共有812条查询结果,搜索用时 953 毫秒
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PC Chamyal A Mehta SL Ojha JR Bhardwaj 《Indian journal of otolaryngology and head and neck surgery》1991,43(1):26-27
Primary tuberculous pathology in nasolpolypi is a rare condition. A case of bilateral ethmoidal polypi with tubercular lesion diagnosed on histopathologlcal examination is being reported and the available relevant literature has been reviewed. 相似文献
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目的:对临床确诊糖尿病患同时测定血清葡萄糖(Glu)及糖化血清蛋白(GSP)的含量,观察二的关系,以及糖化血清蛋白水平对于评价近期(2—3周)糖尿病患血糖在体内变化的临床意义进行了观察。方法:血清葡萄糖、糖化血清蛋白测定均采用酶法测定。结果:178例糖尿病患Glu、GSP均正常3l例占17.4%;Glu、GSP均增高107例占60.1%;Glu正常、GSP增高15例占8.43%;Glu增高、GSP正常25例占14%。结论:糖化血清蛋白的含量不受即时血糖的影响,二的变化不成比例性,对评价糖尿病患2~3周病情的控制是一项灵敏可靠的指标,尤其对于住院病人的治疗与监控有一定的意义。 相似文献
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J E Azevedo M A Fernandez D San Roman E Torrecilla R Esturau J Hernandez T Echeverria A Burgueno J L Delcan 《Revista portuguesa de cardiologia》1992,11(6):531-537
AIM OF STUDY: Evaluation by transesophageal echocardiography of the effect on the characteristics of physiological regurgitant jets (JF) resulting from prosthetic disfunction due to pathologic regurgitation (JF). PATIENTS AND METHODS: We studied 69 consecutive patients with the diagnosis of prosthesis in mitral position using transesophageal echocardiography and color doppler codification. The patients were divided in two groups (N and D groups) according to the presence of prosthesis disfunction by pathologic regurgitation. In each patient we determined planimetric areas and atrial peak depth of each JF and also the sum of JF planimetric areas of each mitral prosthesis. When pathological regurgitation was present we calculated the highest planimetric area, severity degree and atrial peak depth in each JP. RESULTS: The planimetric area in each JF of group N was 330 +/- 167 mm2 and in group D 117 +/- 116 mm2 (p less than 0.001). The sum of the areas of JF in group N was 474 +/- 204 mm2 and in group D 254 +/- 176 mm2 (p less than 0.01). The atrial depth of JF in group was 32 +/- 15 mm and in group D 26 +/- 18 mm (p less than 0.01). In group D 29% of the patients had mild pathological regurgitation, 10% moderate and 61% severe. The maximum planimetric area of JP in group D was 1078 +/- 1007 mm2 with atrial depth of 37 +/- 28 mm. CONCLUSION: The pathological regurgitation in disfunction prosthesis in mitral position has a significant reduction effect in the dimension of prosthesis physiologic regurgitation jets. This transesophageal echocardiographic observation makes it possible to characterize and clarify more precisely the different types of mitral prosthesis jets. 相似文献
5.
C Sanjurjo A R Dawidowsky M S Cameo F Gonzalez Echeverria J A Blaquier 《Journal of andrology》1990,11(5):476-483
A polyclonal antiserum directed against human sperm coating proteins of epididymal origin (anti-KCl) was tested for its ability to alter sperm function. Spermatozoa from normal ejaculates were selected by swim-up separation and capacitated by overnight incubation at room temperature. Exposure of these cells to anti-KCl (0.39 mg protein/ml), prior to their use in the hamster ova penetration test, reduced the penetration of denuded oocytes by 65% (P less than 0.005). Significant inhibitions of lesser magnitude were observed at lower serum concentrations (to 0.098 mg/ml). In an effort to understand the mechanism of this inhibition, other sperm function parameters thought to be related to oocyte penetration were studied. The inhibitory effect was exerted without noticeable changes in sperm motility (determined by the percentage of motile cells and their linear velocity), and in the absence of major sperm agglutination. Anti-KCl did not inhibit the occurrence of spontaneous or induced (by human follicular fluid) acrosome reaction in capacitated spermatozoa. In contrast, exposure to anti-KCl reduced the ability of capacitated spermatozoa to bind tightly to the hamster oolemma. None of these effects were elicited by a control preparation obtained from pre-immune rabbit sera. Exposure of zona-free oocytes to the antiserum did not alter their penetrability by normal sperm. These results suggest that the antigens recognized by anti-KCl participate in some specific step of the sperm-ovum interaction. 相似文献
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Isolation and nucleotide sequence determination of a gene encoding a heat-stable enterotoxin of Escherichia coli. 总被引:56,自引:16,他引:56
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A gene encoding a heat-stable enterotoxin (ST) from an Escherichia coli strain isolated from a human with diarrhea was cloned and characterized by nucleotide sequence analysis. The gene was found to be partially homologous to a previously characterized ST gene from an E. coli strain of bovine origin. Hybridization studies showed that most ST-producing strains of E. coli isolated from humans with diarrhea possess genes highly homologous to either the ST gene from the bovine strain or the ST gene characterized in the present study. 相似文献
9.
Day DJ; Speiser PW; Schulze E; Bettendorf M; Fitness J; Barany F; White PC 《Human molecular genetics》1996,5(12):2039-2048
Steroid 21-hydroxylase deficiency is among the most common inborn errors of
metabolism in man. Characterization of mutations in the 21- hydroxylase
gene (CYP21) has permitted genetic diagnosis, facilitated by the polymerase
chain reaction (PCR). The most common mutation is conversion of an A or C
at nt656 to a G in the second intron causing aberrant splicing of mRNA.
Homozygosity for nt656G is associated with profoundly deficient adrenal
cortisol and aldosterone synthesis, secondary hypersecretion of adrenal
androgens, and a severe form of congenital adrenal hyperplasia (CAH)
characterized by ambiguous genitalia and/or sodium wasting in newborns.
During the course of genetic analysis of CYP21 mutations in CAH families,
we and others have noticed a number of relatives genotyped as nt656G
homozygotes, yet showing no clinical signs of disease. A number of lines of
evidence have led us to propose that the putative asymptomatic nt656G/G
individuals are incorrectly typed due to dropout of one haplotype during
PCR amplification of CYP21. For prenatal diagnosis, we recommend that
microsatellite typing be used as a supplement to CYP21 genotyping in order
to resolve ambiguities at nt656.
相似文献
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