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排序方式: 共有1038条查询结果,搜索用时 31 毫秒
1.
H. S. Markus A. M. Tomkins G. M. Stern 《Journal of neural transmission (Vienna, Austria : 1996)》1993,5(2):117-125
Summary An anthropometric study was performed in 95 subjects (53 male, 42 female) with Parkinson's disease. Weight, height, triceps and biceps skin-fold thicknesses, and mid-arm circumference were recorded. A high incidence of undernutrition was found (23.6% of males and 22.5% of females, as defined by recent British guidelines). A subgroup of severely disabled patients with Parkinson's disease had a significantly lower mean body mass index than a similarly disabled control group with chronic pyramidal upper motor neuron lesions (males 20.6v 23.2 kg/m2 p<0.05; females 20.6v 26.6 kg/m2 p<0.01), suggesting that the undernutrition is not due to chronic illness or immobility alone. Correlation between anthropometric indices and clinical features of disease demonstrated that the presence of moderate or severe dyskinetic movements was the clinical parameter most strongly related to undernutrition. The reduction in anthropometric indices was most marked for skin fold thickness (related to percentage body fat) and least for arm muscle circumference (related to lean body mass); therefore the weight loss seen in Parkinson's disease is primarily due to fat loss rather than muscle loss. 相似文献
2.
Previous work has reported that the 5-hydroxytryptamine (5-HT)1A agonist, 8-hydroxy 2-(di-n-propylamino)tetralin (8-OH DPAT), reduces ethanol intake by rats. However, as 8-OH DPAT reduces 5-HT neurotransmission, these findings are inconsistent with the proposed inhibitory role of central 5-HT neurons on ethanol intake. We examined the effect of 8-OH DPAT on ethanol, water and food intake in rats maintained on a limited access schedule using a lower dose range (6–250 µg/kg) and by assessing concomitant changes in behaviour. Low doses of 8-OH DPAT enhanced ethanol intake even when food and water were offered as alternatives. Suppression in ethanol intake was observed at higher doses where elements of the 5-HT syndrome were apparent. Similar observations were made in both fluid and non-fluid deprived water drinking rats, suggesting the latter effect is non-selective. Therefore 8-OH DPAT may both increase or decrease ethanol consumption in the rat depending on the dose used. 相似文献
3.
Susannah V Quisling Vinay A Shah Ho K Lee Bruno Policeni Wendy R K Smoker Coleman Martin Andrew G Lee 《Journal of neuro-ophthalmology》2006,26(1):47-48
A 44-year-old man with right-sided herpes zoster ophthalmicus (HZO) developed ipsilateral third and sixth cranial nerve palsies and first-division trigeminal (fifth cranial nerve) sensory loss. MRI revealed contrast enhancement of the cisternal and cavernous portions of the third cranial nerve and high signal on a FLAIR sequence within the ipsilateral medulla at the presumed location of the trigeminal nucleus and tract. To our knowledge, this is the first report of the combination of these imaging findings in HZO. 相似文献
4.
J H Van der Walt B Nicholls M Bentley D P Tomkins 《Anaesthesia and intensive care》1987,15(2):151-157
Preoperative and postoperative sedation, postoperative analgesia and vomiting were assessed following four different oral premedications in 143 children aged 1-10 years, weighing 10-30 kg, and undergoing elective adenotonsillectomy or inguinal surgery. Diazepam, diazepam combined with droperidol, trimeprazine and trimeprazine combined with droperidol were compared in a double-blind trial in conjunction with a standardised inhalational anaesthetic technique employing an intraoperative narcotic. Trimeprazine produced significantly more preoperative sedation (P less than 0.001) and was associated with enhanced postoperative analgesia (P less than 0.01). The incidence of postoperative vomiting was significantly less in the group receiving trimeprazine (P less than 0.001). The addition of droperidol to diazepam and trimeprazine only marginally improved the performance of those drugs but significantly prolonged postoperative recovery times. This was more marked when droperidol was combined with trimeprazine. 相似文献
5.
G. Michael Taylor Thomas J. Neuhaus Vanita Shah Susannah Dillon T. Martin Barratt 《Pediatric nephrology (Berlin, Germany)》1997,11(4):404-410
Experimental studies have pointed to charge selectivity as an important determinant of glomerular permeability to macromolecules.
Loss of glomerular basement membrane (GBM) polyanion has been proposed as a cause of the selective proteinuria in minimal
change nephrotic syndrome (MCNS). However, the presence of less-anionic albumin in urine than plasma from MCNS and focal and
segmental glomerulosclerosis (FSGS) patients has been interpreted both as evidence for partial maintenance of charge selectivity
and for involvement of other pathogenic mechanisms. The exact role of charge selectivity in the pathogenesis of nephrotic
proteinuria remains controversial. We have examined the clearance of endogenous proteins of differing size and charge in children
with idiopathic nephrotic syndrome (NS). Chromatofocusing was used to determine the isoelectric points (pIs) of albumins in
paired plasma and urine samples from patients with FSGS (n = 6) and MCNS (n = 6). Charge selectivity was assessed by comparing the pIs of the fractions with the highest albumin concentration (modal
pI) in plasma and urine. The difference between the modal pIs was defined as the delta modal pI. Charge selectivity was also
assessed from the albumin/transferrin and IgG4/IgG1 clearance ratios; size selectivity from the IgG1/albumin and IgG1/transferrin
as well as the IgG4/albumin and IgG4/transferrin clearances. In children with FSGS, the mean (± SD) delta modal pI was – 0.05
± 0.16, and in MCNS – 0.05 ± 0.11. Neither value differed significantly from zero. The albumin/transferrin clearance ratio
showed no significant difference between FSGS and MCNS, but the IgG4/IgG1 clearance ratio was significantly higher in MCNS
(P<0.05). Size selectivity was significantly reduced in FSGS compared with MCNS (for IgG1/transferrin P<0.01 and for IgG1/albumin P<0.05). For IgG4/transferrin and IgG4/albumin, P was <0.05. In conclusion, there was no evidence for residual charge selectivity in idiopathic NS associated with either MCNS
or FSGS during nephrotic-range proteinuria. There was a significant loss of GBM size selectivity in children with FSGS with
heavy proteinuria compared with children with MCNS with heavy proteinuria.
Received August 7, 1996; received in revised form and accepted December 16, 1996 相似文献
6.
Protein-energy malnutrition and risk of infection 总被引:1,自引:0,他引:1
A M Tomkins 《The Proceedings of the Nutrition Society》1986,45(3):289-304
7.
D E Calcagni C A Clyburn G Tomkins G R Gilbert T J Cramer R K Lea S G Ehnes R Zajtchuk 《Telemedicine journal》1996,2(3):211-224
OBJECTIVE: For the last several years the U.S. Department of Defense (DoD) has operated a telemedicine test bed at the U.S. Army Medical Research and Material Command's Medical Advanced Technology Management Office. The goal of this test bed is to reengineer the military health service system from the most forward deployed forces to tertiary care teaching medical centers within the United States by exploiting emerging telemedicine technologies. METHODS: The test bed has conducted numerous proof-of-concept telemedicine demonstrations as part of military exercises and in support of real-world troop deployments. The most ambitious of those demonstrations is Primetime III, an ongoing effort to provide telemedicine and other advanced technology support to medical units supporting Operation Joint Endeavor in Bosnia. RESULTS: Several of the first instances of the clinical use of the Primetime III systems are presented as case reports in this paper. These reports demonstrate capabilities and limitations of telemedicine. CONCLUSION: The Primetime III system demonstrates the technical ability to provide current telecommunications capabilities to medical units stationed in the remote, austere, difficult-to-serve environment of Bosnia. Telemedicine capabilities cannot be used without adequate training, operations, and sustainment support. Video consultations have eliminated the need for some evacuations. The system has successfully augmented the clinical capability of physicians assigned to these medical units. Fullest clinical utilization of telemedicine technologies requires adjustment of conventional clinical practice patterns. 相似文献
8.
Scott E. Guimond Susannah J. Patey Edwin A. Yates Jeremy E. Turnbull 《International journal of experimental pathology》2004,85(4):A62-A63
Introduction Fibroblast growth factors (FGFs) are a multipotent family of growth factors that are important for many biological processes, including development and wound healing. Normal, protease sensitive, prion protein (PrPC) can be converted to the protease resistant, infectious, form (PrPSc) believed to be associated with the pathogenesis of transmissible spongiform encephalopathies. FGFs signal through a family of tyrosine kinase receptors, the FGF receptors (FGFR) with the aid of heparan sulfate (HS), while the role of HS in the biology of PrPC is currently unknown, although depleting cells of HS can prevent production of PrPSc. HS, or its more highly sulfated relation heparin, can exert both positive and negative regulatory activities on a particular FGF‐FGFR combination. The nature of this regulation is determined by the structure of the HS that binds to the proteins. This structure is at least partially determined by the presence of particular sulfate groups along the sugar backbone. Identification of specific sulfate groups that can regulate the activity of proteins has been a long‐term goal in the field. Previously, heparins that had been completely lacking sulfates at specific positions were used to determine the binding and activity requirements for a particular protein. However, this may not necessarily allow for a full examination of the regulatory properties of HS. Here, we present a heparan sulfate analogue library produced by the partial, combinatorial desulfation of heparin. This library was the used to examine the structural properties of heparin required for FGF‐1 signalling through FGFR2c as well as the interactions of HS with PrPC. Materials and methods Porcine intestinal mucosal heparin was subjected to chemical desulfation and enzymatic cleavage. Polysaccharides and oligosaccharides derived from gel filtration chromatography and ion exchange chromatography were tested for their ability to activate FGF signalling through FGF receptors using a BaF3 assay system. Optical biosensors and cell assays were used to study the interaction of PrPC with chemically modified heparin. Results This library possessed vastly more heterogeneity than tissue heparan sulfates, allowing for more systematic screening to help identify those minimal structural features associated with activity. This library was used to examine the different structural features in heparin that support FGF‐1 signalling through FGFR2, showing that HS activity was not strictly dependant on size or charge. In addition, small, low‐sulfated heparins were found to interfere with the PrPC–heparin interaction. Discussion This supports the idea that overall structural features of the HS, rather than just the presence or absence of specific sulfate groups is important for the regulation of protein activity. Future efforts will be focused on further subfractionating the library and identifying specific structural features in HS that support FGF‐1 activity through FGFR2 and other FGFRs as well as the role of HS in the normal function of prion diseases, which may allow for the generation of novel, heparin‐based, therapeutics. 相似文献
9.
Relative carriage rates of nuclear dehydrogenating clostridia in two populations of different colorectal cancer risk
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Carriage of nuclear dehydrogenating clostridia has been associated with colon cancer and implicated in its aetiology. This study has compared the carriage of these organisms in a British population at high risk for the development of colon cancer with a low risk Nigerian population. Clostridia were found in all of the stools from both populations. Nuclear dehydrogenating clostridia were only found in the stools of the British subjects (32%). These results support the suggestion that the carriage rate of nuclear dehydrogenating clostridia in a population is related to the risk of colon cancer. 相似文献
10.
The Human MitoChip: a high-throughput sequencing microarray for mitochondrial mutation detection 总被引:18,自引:0,他引:18
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Maitra A Cohen Y Gillespie SE Mambo E Fukushima N Hoque MO Shah N Goggins M Califano J Sidransky D Chakravarti A 《Genome research》2004,14(5):812-819
Somatic mitochondrial mutations are common in human cancers, and can be used as a tool for early detection of cancer. We have developed a mitochondrial Custom Reseq microarray as an array-based sequencing platform for rapid and high-throughput analysis of mitochondrial DNA. The MitoChip contains oligonucleotide probes synthesized using standard photolithography and solid-phase synthesis, and is able to sequence >29 kb of double-stranded DNA in a single assay. Both strands of the entire human mitochondrial coding sequence (15,451 bp) are arrayed on the MitoChip; both strands of an additional 12,935 bp (84% of coding DNA) are arrayed in duplicate. We used 300 ng of genomic DNA to amplify the mitochondrial coding sequence in three overlapping long PCR fragments. We then sequenced >2 million base pairs of mitochondrial DNA, and successfully assigned base calls at 96.0% of nucleotide positions. Replicate experiments demonstrated >99.99% reproducibility. In matched fluid samples (urine and pancreatic juice, respectively) obtained from five patients with bladder cancer and four with pancreatic cancer, the MitoChip detected at least one cancer-associated mitochondrial mutation in six (66%) of nine samples. The MitoChip is a high-throughput sequencing tool for the reliable identification of mitochondrial DNA mutations from primary tumors in clinical samples. 相似文献