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101.
A young male presenting with cutaneous papules and plaques in a segmental distribution in the pelvic girdle area is reported. The clinical features were suggestive of naevus lipomatosus cutaneous superficialis, but diagnostic biopsy is essential to demonstrate the typical histopathological features and exclude important differential diagnoses such as segmental neurofibromatosis.  相似文献   
102.
Elimination of S100B and renal function after cardiac surgery   总被引:8,自引:0,他引:8  
OBJECTIVES: To determine the biologic half-life of the S100B protein and to investigate if the elimination of S100B depends on glomerular filtration rate (GFR). DESIGN: Prospective human study. SETTING: University hospital. PARTICIPANTS: Sixteen patients who underwent cardiac surgery with cardiopulmonary bypass. INTERVENTIONS: Shed mediastinal blood (autotransfusion) was returned to the patients postoperatively and used to study the kinetics of S100B. Iohexol was infused simultaneously to estimate GFR. S100B was measured at 0, 20, 40, 60, and 180 minutes after infusion. Iohexol was measured at 180 and 240 minutes after infusion. MEASUREMENTS AND MAIN RESULTS: S100B followed first-order kinetics, and the biologic half-life for S100B was determined to be 25.3 +/- 5.1 minutes. GFR was determined to be 63.8 +/- 34.4 mL/min. No correlation was found between GFR and S100B half-life. CONCLUSIONS: The elimination of S100B after cardiac surgery is faster than reported earlier and not affected by a moderate decrease in GFR. This finding is important when evaluating S100B levels after cardiac surgery.  相似文献   
103.
PURPOSE: To evaluate the relationship between posterior capsule folds and an ophthalmic viscosurgical device (OVD) during cataract surgery. SETTING: Parkland Memorial Hospital, Dallas, Texas, USA. METHODS: A prospective observational study of 91 consecutive uneventful cataract extractions by phacoemulsification was performed. The presence or absence of posterior capsule folds was noted immediately after intraocular lens (IOL) implantation and after OVD removal. RESULTS:Posterior capsule folds were present in 21 of 49 cases (43%) with an MA60BM lens (Alcon Laboratories) and in 1 of 42 cases (2%) with an SA30AL lens. In the MA60BM group with folds, the folds were noted before OVD removal in 14 cases and after OVD removal in 16 cases. There was no significant difference in age, sex, axial length, horizontal corneal diameter, or IOL power between groups with and without posterior capsule folds. CONCLUSIONS: The presence of posterior capsule folds does not reliably signify the complete removal of OVDs.  相似文献   
104.
Glioblastomas (GBs) are malignant CNS tumors often associated with devastating symptoms. Patients with GB have a very poor prognosis, and despite treatment, most of them die within 12 months from diagnosis. Several pathways, such as the RAS, tumor protein 53 (TP53), and phosphoinositide kinase 3 (PIK3) pathways, as well as the cell cycle control pathway, have been identified to be disrupted in this tumor. However, emerging data suggest that these aberrations represent only a fraction of the genetic changes involved in gliomagenesis. In this study, we have applied a 32K clone-based genomic array, covering 99% of the current assembly of the human genome, to the detailed genetic profiling of a set of 78 GBs. Complex patterns of aberrations, including high and narrow copy number amplicons, as well as a number of homozygously deleted loci, were identified. Amplicons that varied both in number (three on average) and in size (1.4 Mb on average) were frequently detected (81% of the samples). The loci encompassed not only previously reported oncogenes (EGFR, PDGFRA, MDM2, and CDK4) but also numerous novel oncogenes as GRB10, MKLN1, PPARGC1A, HGF, NAV3, CNTN1, SYT1, and ADAMTSL3. BNC2, PTPLAD2, and PTPRE, on the other hand, represent novel candidate tumor suppressor genes encompassed within homozygously deleted loci. Many of these genes are already linked to several forms of cancer; others represent new candidate genes that may serve as prognostic markers or even as therapeutic targets in the future. The large individual variation observed between the samples demonstrates the underlying complexity of the disease and strengthens the demand for an individualized therapy based on the genetic profile of the patient.  相似文献   
105.
106.
In the troposphere, methanol (CH3OH) is present ubiquitously and second in abundance among organic gases after methane. In the surface ocean, methanol represents a supply of energy and carbon for marine microbes. Here we report direct measurements of air–sea methanol transfer along a ∼10,000-km north–south transect of the Atlantic. The flux of methanol was consistently from the atmosphere to the ocean. Constrained by the aerodynamic limit and measured rate of air–sea sensible heat exchange, methanol transfer resembles a one-way depositional process, which suggests dissolved methanol concentrations near the water surface that are lower than what were measured at ∼5 m depth, for reasons currently unknown. We estimate the global oceanic uptake of methanol and examine the lifetimes of this compound in the lower atmosphere and upper ocean with respect to gas exchange. We also constrain the molecular diffusional resistance above the ocean surface—an important term for improving air–sea gas exchange models.  相似文献   
107.
108.
We describe maternal childbirth goals among women planning either cesarean or vaginal birth. Women in the third trimester planning cesarean or vaginal birth were asked to report up to five childbirth goals. Goal achievement was assessed postpartum. Based on free-text responses, discrete goal categories were identified. Goals and goal achievement were compared between the two groups. Satisfaction was rated on a visual analogue scale and was compared with goal achievement. The sample included 163 women planning vaginal birth and 69 women planning cesarean. Twelve goal categories were identified. Only women planning vaginal birth reported a desire to achieve fulfillment related to childbirth. Women planning cesarean were less likely to express a desire to maintain control over their own responses during childbirth and more likely to report a desire to avoid complications. The 72 women who achieved all stated goals reported significantly higher mean satisfaction scores than the 94 women reporting that at least one goal was not achieved (P = 0.001). Goal achievement was higher among women planning cesarean than among those planning vaginal birth (52.2% versus 23.1%, P < 0.001). This research furthers our understanding of women's attitudes regarding cesarean childbirth and definitions of a successful birth experience.  相似文献   
109.

Background  

The role of both microglial activation and alpha-synuclein deposition in Parkinson's disease remain unclear. We have tested the hypothesis that if microglia play a primary role in Parkinson's disease pathogenesis, the microglial "activated" phenotype should be associated with histopathological and/or clinical features of the disease.  相似文献   
110.
Beran  M; McCredie  KB; Keating  MJ; Gutterman  JU 《Blood》1988,72(2):728-738
The effect of recombinant human tumor necrosis factor alpha (rTNF- alpha) on human myelogenous leukemia clonogenic cells growing either in semisolid media or in suspension cultures was studied and compared with the effect on normal granulocyte-macrophage progenitors (GM-CFC). Exposure of cells to a range of rTNF-alpha doses including pharmacologically achievable plasma concentrations revealed a large heterogeneity in the response of leukemic clonogenic growth to rTNF- alpha. Only one of 13 specimens was highly resistant to rTNF-alpha. Eight of ten leukemic samples were significantly more sensitive than were normal GM-CFC, particularly within the in vivo achievable dose range (1 x 10(0) to 1 x 10(2) ng/mL). No significantly increased inhibition of either normal or leukemic clonogenic growth could be achieved by increasing the rTNF-alpha concentration above 250 ng/mL. Proliferation of leukemic clonogenic cells (L-CFC) was studied in suspension cultures. In five cases the clonogenic cells were significantly inhibited by rTNF-alpha while in one case no inhibition was observed. The inhibition of L-CFC growth by rTNF-alpha was dose dependent between 1 x 10(0) and 1 x 10(2) ng/mL. In suspension cultures, the TNF effect on L-CFC was a function of time of exposure, particularly with low concentrations of TNF. A remarkably higher inhibition of L-CFC as compared with the total leukemic population was observed in suspension cultures. Stimulation of L-CFC growth by rTNF- alpha was not observed. Normal GM-CFC were inhibited by alpha and gamma interferons (INF-alpha, -gamma) in a dose-related manner, with higher sensitivity of colonies than clusters. The response of GM-CFC to combination of recombinant IFNs and TNF was influenced by the size of clones scored and the source of colony-stimulating activity. The response of L-CFC to recombinant IFN-alpha and/or -gamma was highly variable, and sensitivity to one of the lymphokines did not predict for sensitivity to another. The response of L-CFC to combinations of rTNF- alpha and either IFN-alpha or IFN-gamma was complex, varying from synergistic to additive and indifferent. In three of six specimens, IFN- gamma acted antagonistically with rTNF-alpha, a phenomenon not observed with IFN-alpha. These observations suggest that the action of rTNF- alpha in acute myelogenous leukemia could be exploited therapeutically and the dose-time-response relationship should be considered in designing treatment schedules.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
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