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排序方式: 共有793条查询结果,搜索用时 15 毫秒
1.
T W Mattox R O Brown B A Boucher E A Buonpane T C Fabian R W Luther 《JPEN. Journal of parenteral and enteral nutrition》1988,12(6):592-596
The purpose of this study was to evaluate the use of serum fibronectin and serum somatomedin-C as nutritional markers during enteral nutrition support (ENS) of critically ill, traumatized patients using an enteral product containing high concentrations of branched-chain amino acids. Twelve critically injured patients received a standard enteral formula with 30 g of a 44% branched-chain amino acid supplement added to each liter of formula. Fibronectin concentration, somatomedin-C concentration, and nitrogen balance were measured on study days 1, 4, 7, 14, 21, 28 or until adequate oral intake began. Both fibronectin and somatomedin-C concentrations increased significantly from baseline by day 7 of ENS. Nitrogen balance increased significantly from baseline by day 4. On days 14 and 21, only somatomedin-C and nitrogen balance increased significantly from baseline. Nitrogen balance was significantly correlated with somatomedin-C concentration (r = 0.53, p less than 0.01), cumulative caloric intake (r = 0.68, p less than 0.01), and cumulative nitrogen intake (r = 0.72, p less than 0.01). The results of this study suggest that serum somatomedin-C is useful and serum fibronectin has potential in monitoring nutrition support response in critically ill, traumatized patients. 相似文献
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3.
Recognition of the many benign and malignant tumors that occur in the skull base is now simple, given three-dimensional CT scanning and MRI with enhancement. Recent developments in surgical technique have allowed these tumors to be approached, but only in the past two to three years has radical surgery been possible. 相似文献
4.
The facial nerve presents a significant obstacle to adequate surgical exposure of lesions involving the skull base. The evolution of various surgical approaches to the jugular foramen, petrous apex, and lateral facial approaches to the skull base aimed at preserving the seventh cranial nerve are reviewed. Methods and techniques in management of the intratemporal and extratemporal facial nerve are discussed. 相似文献
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6.
P E Pepe K L Mattox R P Fischer C M Matsumoto 《The Journal of trauma》1990,30(9):1125-31; discussion 1131-2
The purpose of this study was to investigate the distribution of various mechanisms of injury and the relative severity of such injury cases throughout the different geographic zones of a large urban area using a computerized emergency medical services (EMS) dispatch/patient record database. The study city (population, 2 million residents) was divided into 156 geographic grids (each 4.5 by 3 miles) and the incidence and relative severity of various injury mechanisms were determined for each zone. Results: In one year (1988), there were more than 115,000 separate EMS incidents involving more than 150,000 patients, 26,000 of whom were transported for injuries incurred in 10,064 motor vehicle accidents, 4,587 falls, 4,015 lacerations/stabwounds, 1,796 beatings, 1,270 gunshots, and 952 auto-pedestrian accidents. Analysis of the 156 zones showed a disproportionate number of EMS responses in the city center with two centralmost grids accounting for about 25% of all responses. Call volume then progressively diminished toward the periphery of the city. However, with some very minor exceptions, the relative incidence and severity of the various injury mechanisms remained proportionally uniform within each zone, regardless of geographic location. Therefore, contrary to popular notoriety, the incidence and associated severity of any given injury type generally was not necessarily predicted by any particular neighborhood predilection for it, but rather by the overall demand for EMS in that zone of the city. 相似文献
7.
Evaluation of three substitutes for Percoll in sperm isolation by density gradient centrifugation 总被引:9,自引:4,他引:9
Silane-coated silica particle solutions (ISolate(TM) and PureSperm)TM)) and
iodixanol (OptiPrep(TM)) were compared to polyvinylpyrrolidone (PVP)-coated
silica particles (Percoll(TM)) in their efficacy to recover spermatozoa by
gradient centrifugation for use in assisted reproductive procedures.
Efficacy was assessed in terms of percentages of sperm recovery, sperm
vitality and motility, normal sperm morphology and normal sperm chromatin
condensation. No significant difference was found in the recovery of
spermatozoa for men with both normal sperm counts and oligozoospermia,
between PVP-coated and silane-coated particle solutions. Iodixanol had
significantly lower sperm recovery compared to the other products. Sperm
vitality, progressive motility, normal morphology and normal chromatin
condensation did not differ significantly between any of the sperm
isolation products.
相似文献
8.
Suppression of vasomotor and vulvovaginal symptoms with continuous oral 17beta-estradiol 总被引:1,自引:0,他引:1
OBJECTIVES: To evaluate the efficacy and safety of different doses of 173-estradiol for the treatment of vasomotor and vulvovaginal symptoms. DESIGN: This was a randomized, double-blind, multicenter, parallel-group study. One hundred forty-five subjects, including naturally postmenopausal women aged 40-60 (who had not experienced menses for at least 12 months), women who had undergone hysterectomy, and women aged 25-60 who had undergone bilateral oophorectomy with or without hysterectomy were studied. Either placebo or 17beta-estradiol (1 mg or 0.5 mg) was given orally every day for 12 weeks, and vasomotor symptoms and vaginal epithelial cytology were evaluated. RESULTS: There were significant differences between placebo and the active treatments in the percentage change from baseline in the number of hot flushes (all hot flushes, 1 mg vs. placebo, p < 0.00 1; 0.5 mg vs. placebo, p = 0.007), with a more substantial proportion of subjects responding in the 1-mg group (mean change in mean number of hot flushes of 83.2%). Both doses were also more effective than placebo in increasing the proportion of mature vaginal cells (end-of-treatment mean values of 0%, 78.5%, and 21.5% for parabasal, intermediate, and superficial cells, respectively, in the 1-mg group; mean values of 0.3%, 80.8%, and 18.9% in the 0.5-mg group; and mean values of 15.2%, 74.7%, and 10.2% in the placebo group). The proportion of subjects reporting no vaginal dryness was greatest in the 1-mg group (mean percentage of days without dryness of 86.1% at weeks 9-12). CONCLUSIONS: For the relief of vasomotor and vulvovaginal symptoms, 17beta-estradiol I mg is effective and has an excellent safety profile. 相似文献
9.
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
10.
Evaluation of a "shotgun" regimen for sudden hearing loss 总被引:3,自引:0,他引:3
One hundred nine patients with idiopathic sudden hearing loss were treated with a "shotgun" regimen that included dextran, histamine, Hypaque, diuretics, steroids, vasodilators, and carbogen inhalation. Thirty-three patients received the entire protocol and 76 patients received most, but not all, of the protocol drugs. Some improvement of hearing (greater than 10 dB in pure-tone average) was seen in 52% of patients treated with the complete protocol and in 54% of patients who received the partial protocol. All patients were analyzed for potential prognostic indicators. Patients with thresholds at 8000 Hz better than at 4000 Hz fared better than the group as a whole. Vertigo at the time of onset of hearing loss was a sign of poor prognosis. There was no correlation between hearing improvement and the age of the patient or the sedimentation rate. Most importantly, there was no statistically significant difference in outcome between patients treated with the complete protocol and those who received only part of the protocol. Furthermore, when the effect of each drug was examined individually, there was no significant difference between those patients receiving and not receiving treatment. The results suggest that this "shotgun" approach for treatment of sudden hearing loss offers no better outcome than is reported in the literature for spontaneous recovery. 相似文献