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81.
A 42-year-old woman, with a previously resected jejunal leiomyoblastoma, was first seen with liver metastases 31/2 years after the tumor resection. Intractable malignant hypercalcemia appeared eight months later, together with renal insufficiency. No osteolytic lesions were detected. Levels of parathyroid hormone, cyclic adenosine monophosphate, and 1,25-dihydroxycholecalciferol (1,25[OH]2D) were not useful in distinguishing between the hypercalcemia of malignancy and concurrent hyperparathyroidism. Despite renal insufficiency, hypercalcemia, and subtotal parathyroidectomy, the 1,25(OH)2D levels remained elevated, consistent with the speculation that a tumor product stimulated 1-alpha-hydroxylation of 25-hydroxycholecalciferol. Phenytoin and phenobarbital (enzyme induction therapy), in combination with phosphorus and glucocorticoids, appeared to be useful in controlling the hypercalcemia.  相似文献   
82.
A group of unique Epstein-Barr virus-containing cell lines was derived from the bone marrow of three patients with X-linked agammaglobulinemia. Efforts to obtain cell lines from the peripheral blood of these patients were uniformly unsuccessful. Immunofluorescence analyses as well as biosynthetic studies with [(35)S]methionine indicated unusual patterns of Ig synthesis in many of these bone marrow derived lines. Seven of the lines were of particular interest in that two produced no Ig of any type; two others showed no Ig by fluorescence but small amounts by [(35)S]methionine labeling; one expressed only cytoplasmic μ chains without any evidence of light chain synthesis, and two produced primarily μ chains with only slight amounts of light chains. One of the lines without membrane or cytoplasmic Ig studied in detail grew like a typical lymphoid line and was carried in intermittent culture over a period of 2 yr without Ig expression. One line grew quite differently and resembled the round cell type described previously, which has been obtained from a variety of sources. The cell line with cytoplasmic μ chains and no light-chain expression had the characteristic properties of pre-B cells. Three normal type Ig-producing cell lines also were obtained from the patients. The accumulated evidence obtained in the present study indicates that these unusual cell lines represent normal precursor cells of the B-cell lineage; these grew out in these cases because of the virtual absence of mature B cells that ordinarily overgrow the culture system. However, the possibility that in certain instances they reflect abnormal Ig synthesis characteristic of the disease has not been ruled out.  相似文献   
83.
Cholesterol ester-rich (CER) VLDL accumulate rapidly in the plasma of rabbits fed cholesterol-enriched diets. However, the major loci of enhanced synthesis of subfractions of CER-VLDL, their interaction with macrophages, and their relative contribution to atherogenesis have not yet been elucidated. To determine whether anabolism is hepatic or intestinal, subfractions of CER-VLDL were characterized at selected intervals from day 0 to 60 of cholesterol feeding. Rate zonal ultracentrifugation of CER-VLDL from rabbits fed cholesterol for 4 and 60 d demonstrated an early increase of the proportion of cholesterol carried in the intestinally-derived fraction (designated as Fx-I) of VLDL compared with that in hepatically-derived particles (Fx-H). Quantification by size exclusion HPLC also demonstrated that Fx-I was a prominent CER-VLDL component at day 4, while Fx-H particles became increasingly prominent with further cholesterol feeding. At both 4 and 60 d Fx-I stimulated cholesterol esterification and intracellular cholesterol content in macrophages more than the corresponding Fx-H did. In fact, Fx-H harvested at 4 d produced no cholesterol ester deposition. In contrast, Fx-H harvested at 60 d markedly stimulated cholesterol esterification and intracellular cholesterol content. Thus, both compositional and metabolic characteristics of CER-VLDL changed as a function of the duration cholesterol feeding.  相似文献   
84.
Patient centeredness is an increasingly recognized aspect of quality health care. The application of this framework to contraceptive counseling and care has not been well described. We propose a definition of patient-centered contraceptive counseling that focuses on and prioritizes each patient’s individual needs and preferences regarding contraceptive methods and the counseling experience. Guided by this definition, we review recent research that has advanced our understanding of how patient-centered contraceptive counseling can be delivered in practice, focusing on how women decide on a contraceptive method, their preferences for counseling, and their experiences with counseling. This research provides evidence that women have diverse preferences around attributes of their contraceptive methods and value personal, supportive relationships with their family planning providers that focus on their individual preferences. We discuss the implications of this research for practice and review recent interventions that incorporate patient centeredness to varying degrees.  相似文献   
85.
Plasmids containing the inosine monophosphate dehydrogenase gene CaIMH3 from Candida albicans strain ATCC 32354 transform their host to resistance against mycophenolic acid (MPA). The transformants maintain the plasmids at a high copy number (20–40 per cell) and express the CaIMH3 gene at very high levels relative to untransformed controls. The plasmid copy number can be controlled by the concentration of MPA in the media. The transformation procedure is reproducible and the efficiency of transformation is high, up to 15,000 per microgram. Unrearranged plasmids are readily recovered by transforming total DNA from transformants back into Escherichia coli. C. albicans genes cloned into the plasmid are expressed at elevated levels relative to untransformed controls. A derivative vector containing the CaMAL2 promoter and termination sequences expresses the CaERG11 ORF at high levels and confers moderate resistance to fluconazole. These shuttle vectors should facilitate global genomics approaches in C. albicans that have been hampered by its diploid genome.  相似文献   
86.
Nonobese diabetic (NOD) mice develop multi-organ autoimmune diseases, including type 1 diabetes. We hypothesized that backcrossing the MHC region from SJL (H-2(s)) mice, which have an endogenous PLP(139-151)-reactive repertoire, onto the background of autoimmune-prone NOD mice would result in a mouse strain that is highly susceptible to experimental autoimmune encephalomyelitis (EAE). Unexpectedly, although we detected an endogenous PLP(139-151) repertoire in the NOD.S mice, they did not develop spontaneous EAE and were relatively resistant to PLP(139-151)-induced EAE when compared to SJL mice. This resistance was associated with lower production of proinflammatory cytokines and a decreased expansion of PLP(139-151)-specific CD4(+) T cells after immunization and restimulation with PLP peptide in vitro. V(beta) chain usage among PLP(139-151)-reactive T cells differed between SJL and NOD.S mice. Furthermore, NOD.S mice were resistant to the development of insulitis and cyclophosphamide-induced diabetes, but not sialadenitis. Altogether, even though NOD mice develop spontaneous autoimmune diseases, they become relatively resistant to induction of EAE even when they express the EAE-permissive class II molecule I-A(s). Our data show that certain combinations of otherwise susceptibility-conferring MHC and non-MHC genes can mediate autoimmune-disease resistance when they are paired together. These findings do not support the "shared autoimmune gene" hypothesis.  相似文献   
87.
Predominance of null mutations in ataxia-telangiectasia   总被引:15,自引:4,他引:15  
Ataxia-telangiectasia (A-T) is an autosomal recessive disorder involving cerebellar degeneration, immunodeficiency, chromosomal instability, radiosensitivity and cancer predisposition. The responsible gene, ATM, was recently identified by positional cloning and found to encode a putative 350 kDa protein with a Pl 3-kinase-like domain, presumably involved in mediating cell cycle arrest in response to radiation-induced DNA damage. The nature and location of A-T mutations should provide insight into the function of the ATM protein and the molecular basis of this pleiotropic disease. Of 44 A-T mutations identified by us to date, 39 (89%) are expected to inactivate the ATM protein by truncating it, by abolishing correct initiation or termination of translation, or by deleting large segments. Additional mutations are four smaller in-frame deletions and insertions, and one substitution of a highly conserved amino acid at the Pl 3-kinase domain. The emerging profile of mutations causing A-T is thus dominated by those expected to completely inactivate the ATM protein. ATM mutations with milder effects may result in phenotypes related, but not identical, to A-T.   相似文献   
88.
The study presented here was performed in order to create a rule that identifies subjects at high risk for invasive candidiasis in the intensive care setting. Retrospective review and statistical modelling were carried out on 2,890 patients who stayed at least 4 days in nine hospitals in the USA and Brazil; the overall incidence of invasive candidiasis in this group was 3% (88 cases). The best performing rule was as follows: Any systemic antibiotic (days 1–3) OR presence of a central venous catheter (days 1–3) AND at least TWO of the following—total parenteral nutrition (days 1–3), any dialysis (days 1–3), any major surgery (days −7–0), pancreatitis (days −7–0), any use of steroids (days −7–3), or use of other immunosuppressive agents (days −7–0). The rate of invasive candidiasis among patients meeting the rule was 9.9%, capturing 34% of cases in the units, with the following performance: relative risk 4.36, sensitivity 0.34, specificity 0.90, positive predictive value 0.01, and negative predictive value 0.97. The rule may identify patients at high risk of invasive candidiasis. Results of this project were partially presented at Focus on Fungal Infections 14, New Orleans, LA, USA, 2004. Abstract no. 51.  相似文献   
89.

Background

Most consider Twitter as a tool purely for social networking. However, it has been used extensively as a tool for online discussion at nonmedical and medical conferences, and the academic benefits of this tool have been reported. Most anesthetists still have yet to adopt this new educational tool. There is only one previously published report of the use of Twitter by anesthetists at an anesthetic conference. This paper extends that work.

Objective

We report the uptake and growth in the use of Twitter, a microblogging tool, at an anesthetic conference and review the potential use of Twitter as an educational tool for anesthetists.

Methods

A unique Twitter hashtag (#WSM12) was created and promoted by the organizers of the Winter Scientific Meeting held by The Association of Anaesthetists of Great Britain and Ireland (AAGBI) in London in January 2012. Twitter activity was compared with Twitter activity previously reported for the AAGBI Annual Conference (September 2011 in Edinburgh). All tweets posted were categorized according to the person making the tweet and the purpose for which they were being used. The categories were determined from a literature review.

Results

A total of 227 tweets were posted under the #WSM12 hashtag representing a 530% increase over the previously reported anesthetic conference. Sixteen people joined the Twitter stream by using this hashtag (300% increase). Excellent agreement (κ = 0.924) was seen in the classification of tweets across the 11 categories. Delegates primarily tweeted to create and disseminate notes and learning points (55%), describe which session was attended, undertake discussions, encourage speakers, and for social reasons. In addition, the conference organizers, trade exhibitors, speakers, and anesthetists who did not attend the conference all contributed to the Twitter stream. The combined total number of followers of those who actively tweeted represented a potential audience of 3603 people.

Conclusions

This report demonstrates an increase in uptake and growth in the use of Twitter at an anesthetic conference and the review illustrates the opportunities and benefits for medical education in the future.  相似文献   
90.
Bacterial vaginosis (BV) is the most common gynecological infection in the United States. Diagnosis based on Amsel''s criteria can be challenging and can be aided by laboratory-based testing. A standard method for diagnosis in research studies is enumeration of bacterial morphotypes of a Gram-stained vaginal smear (i.e., Nugent scoring). However, this technique is subjective, requires specialized training, and is not widely available. Therefore, a highly accurate molecular assay for the diagnosis of BV would be of great utility. We analyzed 385 vaginal specimens collected prospectively from subjects who were evaluated for BV by clinical signs and Nugent scoring. We analyzed quantitative real-time PCR (qPCR) assays on DNA extracted from these specimens to quantify nine organisms associated with vaginal health or disease: Gardnerella vaginalis, Atopobium vaginae, BV-associated bacteria 2 (BVAB2, an uncultured member of the order Clostridiales), Megasphaera phylotype 1 or 2, Lactobacillus iners, Lactobacillus crispatus, Lactobacillus gasseri, and Lactobacillus jensenii. We generated a logistic regression model that identified G. vaginalis, A. vaginae, and Megasphaera phylotypes 1 and 2 as the organisms for which quantification provided the most accurate diagnosis of symptomatic BV, as defined by Amsel''s criteria and Nugent scoring, with 92% sensitivity, 95% specificity, 94% positive predictive value, and 94% negative predictive value. The inclusion of Lactobacillus spp. did not contribute sufficiently to the quantitative model for symptomatic BV detection. This molecular assay is a highly accurate laboratory tool to assist in the diagnosis of symptomatic BV.  相似文献   
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