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11.
1,6—二磷酸果糖对手术后应激病人应用全肠外营养支持效果的影响 总被引:3,自引:1,他引:2
本文在胃癌行全胃或胃大部切除术引起的中等程度应激病人,随机分组对比观察了全肠外营养或TPN加用1,6-二磷酸果糖的效果。结果显示,与单纯TPN相比,TPN加用FDP后血清皮质醇和胰高血糖素等应激激素水平有所下降,尿中3-甲基组氨酸排出减少,累积氮平衡增加。 相似文献
12.
本文在国内首次报道了纤维素固相RIA法测定甲胎蛋白。本法简便灵敏,快迅稳定,平均回收率95.7±8.08%,批间变异系数r=7.8±1.7%,批内变异系数r=5.8±2.6%,线性关系较好(r=0.999),灵敏度比液相RIA提高6倍,32份血样品用双位点夹心法和试剂盒的液相RIA进行比较,结果经统计学处理,相关系数分别为r=0.82,r=0.80,均具有显著相关性。 相似文献
13.
Mutation spectrum and genotype-phenotype analyses in Cowden disease and Bannayan-Zonana syndrome, two hamartoma syndromes with germline PTEN mutation 总被引:22,自引:1,他引:22
Marsh DJ; Coulon V; Lunetta KL; Rocca-Serra P; Dahia PL; Zheng Z; Liaw D; Caron S; Duboue B; Lin AY; Richardson AL; Bonnetblanc JM; Bressieux JM; Cabarrot-Moreau A; Chompret A; Demange L; Eeles RA; Yahanda AM; Fearon ER; Fricker JP; Gorlin RJ; Hodgson SV; Huson S; Lacombe D; Eng C 《Human molecular genetics》1998,7(3):507-515
The tumour suppressor gene PTEN , which maps to 10q23.3 and encodes a 403
amino acid dual specificity phosphatase (protein tyrosine phosphatase;
PTPase), was shown recently to play a broad role in human malignancy.
Somatic PTEN deletions and mutations were observed in sporadic breast,
brain, prostate and kidney cancer cell lines and in several primary tumours
such as endometrial carcinomas, malignant melanoma and thyroid tumours. In
addition, PTEN was identified as the susceptibility gene for two hamartoma
syndromes: Cowden disease (CD; MIM 158350) and Bannayan-Zonana (BZS) or
Ruvalcaba-Riley-Smith syndrome (MIM 153480). Constitutive DNA from 37 CD
families and seven BZS families was screened for germline PTEN mutations.
PTEN mutations were identified in 30 of 37 (81%) CD families, including
missense and nonsense point mutations, deletions, insertions, a
deletion/insertion and splice site mutations. These mutations were
scattered over the entire length of PTEN , with the exception of the first,
fourth and last exons. A 'hot spot' for PTEN mutation in CD was identified
in exon 5 that contains the PTPase core motif, with 13 of 30 (43%) CD
mutations identified in this exon. Seven of 30 (23%) were within the core
motif, the majority (five of seven) of which were missense mutations,
possibly pointing to the functional significance of this region. Germline
PTEN mutations were identified in four of seven (57%) BZS families studied.
Interestingly, none of these mutations was observed in the PTPase core
motif. It is also worthy of note that a single nonsense point mutation,
R233X, was observed in the germline DNA from two unrelated CD families and
one BZS family. Genotype-phenotype studies were not performed on this small
group of BZS families. However, genotype-phenotype analysis inthe group of
CD families revealed two possible associations worthy of follow-up in
independent analyses. The first was an association noted in the group of CD
families with breast disease. A correlation was observed between the
presence/absence of a PTEN mutation and the type of breast involvement
(unaffected versus benign versus malignant). Specifically and more
directly, an association was also observed between the presence of a PTEN
mutation and malignant breast disease. Secondly, there appeared to be an
interdependent association between mutations upstream and within the PTPase
core motif, the core motif containing the majority of missense mutations,
and the involvement of all major organ systems (central nervous system,
thyroid, breast, skin and gastrointestinal tract). However, these
observations would need to be confirmed by studying a larger number of CD
families.
相似文献
14.
Dynamic CT features of hepatic abscesses 总被引:31,自引:0,他引:31
Forty hepatic abscesses were examined with dynamic computed tomography (CT). A "double target sign," consisting of a hypodense central area surrounded by first a hyperdense ring and then a hypodense zone, seems to be highly suggestive of abscess formation. In 12 cases, the hepatic parenchyma surrounding the lesion demonstrated transient hyperdensity after contrast injection, possibly due to localized hepatic venous obstruction secondary to acute hepatic inflammation. This is similar to the appearance of an arterioportal fistula. 相似文献
15.
Salvatore Cicciarello Guglielmo Borgia Jane Crowell Rocco Ciampi Raimondo Cerini Raffaele Orlando Michelina Mainolfi Laura Reynaud Michele Milano Marcello Piazza 《European journal of epidemiology》1997,13(1):49-54
HCV is ubiquitous. In 50% of all cases it causes chronic hepatitis that often evolves into liver cirrhosis and hepatocellular carcinoma. Recently HCV has been classified in 5 genotypes by Okamoto. The purpose of this study is to evaluate the prevalence of 5 genotypes in Campania, a region of Southern Italy, where the prevalence of anti-HCV antibodies ranges from 0.87 to 4%, and to evaluate the correlation between the HCV genotypes and the severity of histological damage. One hundred and thirty-five anti-HCV positive patients were enrolled and tested by PCR to identify HCV-RNA. One hundred and twenty-four patients resulted HCV-RNA positive. Genotyping was performed as described by Okamoto et al. with minor modifications of the specific primer to type III proposed by Silini et al. Eight patients were negative for all genotypes. Eight patients were positive for type I(1a), 61 for type II(1b), 39 for type III(2a), 11 for type IV(2b) and 1 for type V(3a). In 4 cases two different genotypes were present in the same sample [II(1b)-IV(2b), III(2a)-II(1b) twice, III(2a)-IV(2b)]. Histological evaluation of liver damage showed: CPH (22 cases), minimal CAH (56), severe CAH (31) and liver cirrhosis (15). There was no statistically significant correlation between the 5 genotypes and the severity of histological damage. Data on the prevalence of genotype II(1b) in Italy are similar to those reported for other European countries. The prevalence of genotypes in Southern Italy is similar to that reported in the population of Northern Italy. 相似文献
16.
Alan P. Brown Debra L. Kirchner Robert L. Morrissey Saroj R. Das Robert L. Fitzgerald James A. Crowell Barry S. Levine 《Drug development research》2003,58(2):169-178
Cancer chemoprevention is the use of pharmacologic agents to inhibit the development of cancer. The adrenal steroid dehydroepiandrosterone (DHEA) has demonstrated chemopreventive efficacy in animal models of tumorigenesis. However, due to DHEA's undesirable hormonal actions, the fluorinated analog fluasterone (fl‐DHEA), which also has chemopreventive characteristics, was synthesized as a potential alternate agent. It is not known whether fl‐DHEA has hormonal actions. The endocrinologic effects of DHEA and fl‐DHEA in adult male and female Fischer 344 rats were examined following 28 days of daily oral treatment. Initial doses tested were 30 and 300 mg/kg/day for each drug (n=12/sex/group), which are equivalent to 104 and 1,042 µmoles/kg/day DHEA, and 103 and 1,034 µmoles/kg/day fl‐DHEA. However, due to weight loss at the high dose, doses were lowered to 150 mg/kg/day for each drug (521 and 517 µmoles/kg/day DHEA and fl‐DHEA, respectively). Administration of DHEA resulted in dose‐dependent increases in plasma DHEA and DHEA‐S 1 h after dosing in week 4. DHEA produced an estrogenic effect in female rats expressed as decreased plasma FSH and LH, inhibition of ovulation, prolonged estrus, and increased uterine estrogen receptors. DHEA also increased plasma levels of androstenedione in males and females. Administration of fl‐DHEA increased the estrus cycle length due to a prolonged diestrus II phase and decreased the weights of the uterus, prostate, seminal vesicles, and testes. In addition, fl‐DHEA decreased plasma FSH, LH, and tissue estradiol, and increased plasma dihydrotestosterone levels in both sexes. These results indicate that fl‐DHEA is hormonally active and additional studies are warranted to further describe its endocrinologic effects. Drug Dev. Res. 58:169–178, 2003. © 2003 Wiley‐Liss, Inc. 相似文献
17.
OBJECTIVE: The ketogenic diet is a high-fat, low-protein, low-carbohydrate diet developed in the 1920s for the treatment of children with difficult to control seizures. Despite advances in both the pharmacotherapy and the surgery of epilepsy, many children continue to have difficult-to-control seizures. This prospective study sought to determine the ketogenic diet's effectiveness and tolerability in children refractory to today's medications. METHODS: One hundred fifty consecutive children, ages 1 to 16 years, virtually all of whom continued to have more than two seizures per week despite adequate therapy with at least two anticonvulsant medications, were prospectively enrolled in this study, treated with the ketogenic diet, and followed for a minimum of 1 year. Seizure frequency was tabulated from patients' daily seizure calendars and seizure reduction calculated as percentage of baseline frequency. Adverse events and reasons for diet discontinuation were recorded. RESULTS: The children (mean age, 5.3 years), averaged 410 seizures per month before the diet, despite an exposure to a mean of 6.2 antiepileptic medications. Three months after diet initiation, 83% of those starting remained on the diet and 34% had >90% decrease in seizures. At 6 months, 71% still remained on the diet and 32% had a >90% decrease in seizures. At 1 year, 55% remained on the diet and 27% had a >90% decrease in seizure frequency. Most of those discontinuing the diet did so because it was either insufficiently effective or too restrictive. Seven percent stopped because of intercurrent illness. CONCLUSIONS: The ketogenic diet should be considered as alternative therapy for children with difficult-to-control seizures. It is more effective than many of the new anticonvulsant medications and is well tolerated by children and families when it is effective. 相似文献
18.
We report a case of an assisted pregnancy in an asymptomatic woman who was found to have an extrauterine mass on ultrasound and MRI. This complex mass had equivocal imaging features and was found to be a ruptured ovarian ectopic pregnancy at surgery. This case illustrates that vigilance is required regarding the possibility of coexisting ectopic and intrauterine pregnancy following assisted conception, even in entirely asymptomatic cases. 相似文献
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