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31.
Body art in the form of tattoos and piercing has become increasingly popular amongst children and teenagers, and is nowadays more socially acceptable despite media reports citing tissue destruction and death. Our study explored the awareness and experience of patients with congenital heart disease, and of cardiologists and professionals responsible for their care.  相似文献   
32.
Status of percutaneous catheter drainage of abscesses   总被引:1,自引:0,他引:1  
The definitive role of catheter drainage in the therapy of abscesses has not yet been totally elucidated. The resolution rate of intra-abdominal infection with catheter drainage is highly variable, depending on the inclusion criteria employed. Certain infections are very effectively treated (i.e., abscesses that are single, not communicating with abdominal viscera, noncancerous, and bacterial) with simple catheter drainage, whereas others (i.e., infected pancreatic tumor phlegmon) prove to be much more resistant to simple catheter drainage. When all intra-abdominal "abscesses" are collected, the success of catheter drainage ranges from 47 per cent to 73 per cent. The wide variation should be seen not so much as a reflection of differences in technical ability of the radiologist to introduce a catheter, but rather as emblematic of the highly variable nature of the cause of intra-abdominal infection and the definition of an abscess. Hospitals with a large number of complex problems such as malignancy, transplant and other immunosuppressed patients, and referrals of patients with complex long-standing intra-abdominal infections are likely to have a much lower rate of success with percutaneously placed catheters than are those institutions that derive their series from post-traumatic or primary diseases such as appendiceal or diverticular disease. In the former series, a higher morbidity and mortality rate would be expected from any form of treatment when compared to a series from a practice based on more primary care problems. Intra-abdominal infections are a heterogeneous set of processes, and the role of interventional radiology in the diagnostic and therapeutic approach cannot be underestimated. In planning for the care of a patient with a presumed intra-abdominal infectious process, percutaneous aspiration of a fluid mass is an effective tool for establishing the diagnosis of an abscess. The brief introduction of a catheter has rarely led to contamination of an otherwise sterile collection. However, it often effects dramatic symptomatic relief if the fluid collection is infected. It has therefore been an evolving recommendation to employ the techniques of interventional radiology aggressively in a diagnostic capacity. Subsequently, therapeutic interventions can be undertaken in joint agreement among the physician, surgeon, and radiologist. The diagnosis and treatment of intra-abdominal infections can often times be carried out in a relatively easy and non-morbid manner that effects cure in a significant percentage of patients.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
33.
A reassessment of Holt's data on: "The question of lumbar discography"   总被引:3,自引:0,他引:3  
This paper is a detailed critique of Holt's study entitled "The Question of Lumbar Discography." His finding of a 37% false positive rate in asymptomatic volunteers has been used to discredit lumbar discography as a valid diagnostic study in the investigation of low back pain patients with nonprolapsing disc disease of the lumbar spine. The authors show why Holt's paper should no longer be used as scientific and authoritative evidence against the use of discography by today's standards.  相似文献   
34.
35.
Human ORFeome Version 1.1: A Platform for Reverse Proteomics   总被引:6,自引:0,他引:6       下载免费PDF全文
The advent of systems biology necessitates the cloning of nearly entire sets of protein-encoding open reading frames (ORFs), or ORFeomes, to allow functional studies of the corresponding proteomes. Here, we describe the generation of a first version of the human ORFeome using a newly improved Gateway recombinational cloning approach. Using the Mammalian Gene Collection (MGC) resource as a starting point, we report the successful cloning of 8076 human ORFs, representing at least 7263 human genes, as mini-pools of PCR-amplified products. These were assembled into the human ORFeome version 1.1 (hORFeome v1.1) collection. After assessing the overall quality of this version, we describe the use of hORFeome v1.1 for heterologous protein expression in two different expression systems at proteome scale. The hORFeome v1.1 represents a central resource for the cloning of large sets of human ORFs in various settings for functional proteomics of many types, and will serve as the foundation for subsequent improved versions of the human ORFeome.  相似文献   
36.
Nearly all of the open reading frames (ORFs) of the yeast Saccharomyces cerevisiae have been synthesized by PCR using a set of ~6000 primer pairs. Each of the forward primers has a common 22-base sequence at its 5′ end, and each of the back primers has a common 20-base sequence at its 5′ end. These common termini allow reamplification of the entire set of original PCR products using a single pair of longer primers—in our case, 70 bases. The resulting 70-base elements that flank each ORF can be used for rapid and efficient cloning into a linearized yeast vector that contains these same elements at its termini. This cloning by genetic recombination obviates the need for ligations or bacterial manipulations and should permit convenient global approaches to gene function that require the assay of each putative yeast gene.  相似文献   
37.
Using combinations of methods for detecting Fc receptors and B lymphocytes, non-B, non-T lymphocytes and T lymphocytes we have shown TG cells to be significantly increased in rheumatoid arthritis (RA) patients' peripheral blood lymphocytes (PBL). The possible significance of this finding to the disease process is discussed.  相似文献   
38.
Human chromosome 11p15.5 and distal mouse chromosome 7 include a megabase-scale chromosomal domain with multiple genes subject to parental imprinting. Here we describe mouse and human versions of a novel imprinted gene, IMPT1 , which lies between IPL and p57 KIP2 and which encodes a predicted multi-membrane-spanning protein similar to bacterial and eukaryotic polyspecific metabolite transporter and multi- drug resistance pumps. Mouse Impt1 and human IMPT1 mRNAs are highly expressed in tissues with metabolite transport functions, including liver, kidney, intestine, extra-embryonic membranes and placenta, and there is strongly preferential expression of the maternal allele in various mouse tissues at fetal stages. In post-natal tissues there is persistent expression, but the allelic bias attenuates. An allelic expression bias is also observed in human fetal and post-natal tissues, but there is significant interindividual variation and rare somatic allele switching. The fact that Impt1 is relatively repressed on the paternal allele, together with data from other imprinted genes, allows a statistical conclusion that the primary effect of human chromosome 11p15.5/mouse distal chromosome 7 imprinting is domain-wide relative repression of genes on the paternal homolog. Dosage regulation of the metabolite transporter gene(s) by imprinting might regulate placental and fetal growth.   相似文献   
39.
Bone cell populations and histomorphometric correlates to function   总被引:1,自引:0,他引:1  
A circadian context has been used to develop information about the proliferative and functional behavior of the cell populations that function to model the long bones of growing rats. We asked: Are the proliferating cells in the growth cartilages and diaphyseal bone of young adult growing rats distributed within single or multiple populations? Can cytomorphometry (TEM-C) be used to determine ultrastructural correlates to the well-defined circadian rhythm of matrix formation displayed by functionally synchronous populations of metaphyseal osteoblasts? Can TEM-C reveal changes in osteoclast ultrastructure that could index a biological rhythm for osteoclastic bone mineralysis/resorption? Kinetic results derived from multiple radiothymidine labeling (DNA synthesis) support the single population model for chondrocytes and diaphyseal osteoprogenitor cells. TEM-C studies at the midpoints of the daily light and dark spans show that osteoblast RER-membrane development and cysternal volumes are maximal at the recorded daytime peak of net collagen synthesis. The extent of metaphyseal osteoclast surface ruffling (mineralysis) is also twofold greater during the day than the night--an observation supporting the concept that bone formation and resorption activities are coupled.  相似文献   
40.
The effect of vasoactive intestinal peptide (VIP) upon adenylate cyclase (AC) activity has been determined in defined microdissected renal tubules isolated from collagenase-treated rabbit kidneys. In the presence of 10 M GTP, 1 M VIP gave marked stimulations of AC over basal values in the bright portion of the distal convoluted tubule (DCTb) (10.1-fold), and in the collecting tubule isolated from the inner stripe of the outer medulla (OMCTi, 7.8-fold). Less pronounced effects of VIP were found in the medullary collecting tubule isolated from the outer stripe (2.5-fold) and in the granular portion of the distal convoluted tubule (2.0-fold). VIP stimulation of AC activity in these segments amounted to 25 to 40% of the effect elicited by other agonists (arginine vasopressin, calcitonin or parathyroid hormone) in their respective target segments. A low response to VIP was observed in the cortical thick ascending limb (1.8-fold) which represented less than 5% of the calcitonin-stimulated AC activity. In the thin descending limb VIP produced a slight and variable stimulation of AC. VIP was without effect upon AC in the convoluted and straight portions of the proximal tubule, the medullary thick ascending limb and the cortical collecting tubule. Halfmaximal stimulation of AC by VIP was observed at 26±10 nM (n=3) in OMCTi and at 19 nM (n=2) in DCTb. Related peptides glucagon, secretin and PHI gave lower stimulations of AC compared to VIP in OMCTi. Conversely for rat OMCTi, under identical conditions, glucagon was much more effective than VIP.  相似文献   
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