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1.
  总被引:1,自引:0,他引:1  
Prolonged vascularized organ allograft survival and an improved quality of life are now possible for many transplant recipients. These advances are due largely to greater understanding of the immune response, the development of potent immunosuppressive agents (cyclosporin A), and improved surgical techniques. Thus more of these patients may require surgical procedures related or unrelated to their original operation, and the plastic surgeon, among other specialists, should be aware of the special problems of the immunocompromised transplant recipient who needs to undergo reconstructive surgery. We report our experience with 15 kidney, heart, and liver transplant recipients who required reconstructive surgery for a variety of conditions. The combined team approach by reconstructive and transplant surgeons is described, as well as the perioperative drug protocol and the special problems that immunosuppressed transplant recipients present. We conclude that these patients can successfully undergo major reconstructive procedures as long as the plastic surgeon not only performs technically flawless surgery, but also familiarizes himself or herself with the special problems of the immunosuppressed host, including the ever-present risk of sepsis and delayed and impaired wound healing, the potential for acute Addisonian crisis, and the possibility of multiple complicating comorbid conditions.  相似文献   
2.
Besides checking estimates of effectiveness and safety of using the proprietary Harpagophytum extract Doloteffin, this postmarketing surveillance compared various disease-specific* and generic** measures of effect. We enrolled 250 patients suffering from nonspecific low back pain (Back group: n = 104) or osteoarthritic pain in the knee (Knee group: n = 85) or hip (Hip group: n = 61). They took an 8-week course of Doloteffin at a dose providing 60 mg harpagoside per day. The measures of effect on pain and disability included the percentage changes from baseline of established instruments (Arhus low back pain index*, WOMAC index*, German version of the HAQ**) and unvalidated measures (total pain index*, three score index*, the patient's global assessment** of the effectiveness of treatment). Patients also received a diary for the daily recording of their pain and any additional treatments for it. The three groups differed in age, weight and characteristics of initial pain. 227 patients completed the study. Multivariate analysis confirmed that several dimensions of effect were recorded by the several outcome measures but, in all groups, both the generic and disease-specific outcome measures improved by week 4 and further by 8. In multivariable analysis, the improvement tended to be more when the initial pain and disability score was more: older patients tended to improve less than younger, the hip group tended to improve convincingly more than the back group, whereas the improvement in the knee group was less readily differentiated from that in the back group. The subgroup of Back patients who required NSAIDs during the 8 weeks used significantly more per patient than patients in the other two groups, but that requirement also declined more with time. About 10% of the patients suffered from minor adverse events that could possibly have been attributable to Doloteffin. Between 50% and 70% of the patients benefitted from Doloteffin with few adverse effects. Thus, Doloteffin is well worth considering for osteoarthritic knee and hip pain and nonspecific low back pain.  相似文献   
3.
    
The RNA-P and DNA-P content of the nucleus and the RNA-P content of the whole cell of the livers of 8- to 20-day chick embryos and of adult fowls have been determined. The DNA-P content of the liver nuclei was slightly higher in the 8- and 10-day embryo than in all the other stages examined. A significant decrease in the RNA content of the cell occurred during embryonic development. The RNA content of the adult cell was the same as that of the 14- to 16-day embryo. The proportion of the cellular RNA contributed by the nucleus also decreased during development. In respect to both nuclear RNA content and distribution of RNA between nucleus and cytoplasm, the adult resembled the 8- to 12-day embryo. Examination of the fine structure of the cell showed that, as development progressed, free ribosomes decreased in number and the rough membranes increased. Slices of 8-, 14-, and 20-day embryonic livers and of adult livers were incubated with 14C-leucine, and the amount of labeled amino acid incorporated into whole tissue protein and into the proteins of the subcellular fractions was measured. Embryonic liver incorporated 14C-leucine 15 to 30 times more rapidly than adult liver. The microsomal protein was always more highly labelled than the protein in any other subcellular fraction; however, in the 8-day embryonic and the adult liver the proportion of total counts found in the nuclear fraction was considerably higher than in the 14- or 20-day embryonic liver. The significance of an apparent correlation between the proportion of the cell's RNA contributed by the nucleus and the proportion of total counts in the nuclear fraction is discussed.  相似文献   
4.
Consider a large random mating monoecious diploid population that has N individuals in each generation. Let us assume that at time 0 a random sample of ninfinity. It is then possible to obtain a generalization of coalescent theory for haploid populations if the distribution of G1 has a finite second moment and E[G(1)(3)]/N-->0 as N-->infinity.  相似文献   
5.
A new method was devised for the isolation of foetal and neonatal rat lvier mitochondria, giving higher yields than conventional methods. 2. During development from the perinatal period to the mature adult, the ratio of cytochrome oxidase/succinate-cytochrome c reductase changes. 3. The inner mitochondrial membrane of foetal liver mitochondria possesses virtually no osmotic activity; the permeability to sucrose decreases with increasing developmental age. 4. Foetal rat liver mitochondria possess only marginal respiratory control and do not maintain Ca2+-induced respiration; they also swell in respiratory-control medium in the absence of substrate. ATP enhances respiratory control and prevents swelling, adenylyl imidodiphosphate, ATP+atractyloside enhance the R.C.I. (respiratory control index), Ca2+-induced respiratory control and prevent swelling, whereas GTP and low concentrations of ADP have none of these actions. It is concluded that the effect of ATP depends on steric interaction with the inner mitochondrial membrane. 5. When 1-day pre-partum foetuses are obtained by Caesarean section and maintained in a Humidicrib for 90 min, mitochondrial maturation is triggered, so that their R.C.I. is enhanced and no ATP is required to support Ca2+-dependent respiratory control or to inhibit mitochondrial swelling. 6. It is concluded that foetal rat liver mitochondria in utero do not respire, although they are capable of oxidative phosphorylation in spite of their low R.C.I. The different environmental conditions which the neonatal rat encounters ex utero enable the hepatic mitochondria to produce ATP, which interacts with the inner mitochondrial membrane to enhance oxidative phosphorylation by an autocatalytic mechanism.  相似文献   
6.
Consider a random mating population that has N(m) males and N(f) females in each generation. Let us assume that at time 0 a random sample of n copies of a gene is taken from this population. Then, for models introduced by Wright [Evolution in Mendelian populations, Genetics 16 (1931) 97; Inbreeding and homozygosis, Proc. Nat. Acad. Wash. 19 (1933) 420; Evolution and the Genetics of Populations, The Theory of Gene Frequencies, vol. II, The University of Chicago, Chicago and London, 1969.], it is possible to obtain generalizations of the haploid theory of genealogical processes developed by Felsenstein . It is conjectured that these hold generally, regardless of the effective population size, if n相似文献   
7.
    
A receptor for aldosterone was studied in the cytosol of rectal mucosa of two sisters (M.A., M.B.) with the clinical manifestations of pseudohypoaldosteronism (PHA). Compared to age matched controls the patients showed a decreased affinity for aldosterone (M.A. Kd1: 0.18 nM, Kd2: 4.55 nM; Nmax1: 0.185 fmol/mg cytosol protein (CP), Nmax2: 3.12 fmol/mg CP, respectively). In an attempt to find an explanation for the phenomenon of stress-induced electrolyte imbalance in PHA patients an experimental set up was designed, using aldosterone antibody material as artificial aldosterone receptor. Specific binding was evaluated in addition with and without a 25-100-fold molar excess of dexamethasone (DEX) in order to overcome the glucocorticoid affinity of the aldosterone receptor, a phenomenon proposed to be the cause for the severe consequences of stress in some patients with PHA. The aldosterone antiserum showed two binding sites, similar to the natural receptor (Kd1: 0.15 nM, Kd2: 1.30 nM; Nmax: 30 fmol/mg CP and 130 fmol/mg CP, respectively). Under the influence of DEX the high affinity binding site (Kd1) was occupied by the glucocorticoidanalogon (Kd: 1.30 nM; Nmax: 125 fmol/mg CP). In conclusion, in stress situations, with increased quantities of glucocorticoid circulating, the high affinity binding site of the aldosterone receptor might be occupied by the glucocorticoids, while the low affinity binding site in PHA patients might not have sufficient binding capacity to maintain the electrolyte balance.  相似文献   
8.
Although it is well-known that AMPA receptors are involved in spatial learning and memory, published data on GluR3 and GluR4 are limited. Moreover, there is no information about GluR3 and GluR4 receptor complex levels in spatial memory training. It was therefore the aim of the study to determine the above-mentioned receptor levels following training in the Multiple T-Maze (MTM). Results from the MTM and hippocampal membrane proteins from C57BL/6J mice were taken from an own previous study and GluR3 and GluR4 receptor complexes were run on blue native gel electrophoresis followed by immunoblotting and quantification of bands. Subsequently, GluR3 and GluR4 were identified under denaturing conditions from two-dimensional gels by mass spectrometry (nano-LC-ESI-MS/MS). Hippocampal levels of GluR3 containing complexes (apparent molecular weight between 480 and 720) were decreased while GluR4 containing complexes (apparent molecular weight between 480 and 720) were increased. GluR4 complex levels in trained mice were correlating with latency and speed. Mass spectrometry unambiguously identified the two receptor subunits. The findings show that GluR3 and GluR4 may have different functions in the processes of spatial memory training in the MTM and indeed, different neurobiological functions of the two receptor subunits have been already reported. GluR3 and GluR4 receptor complex rather than subunit levels are paralleling training in the MTM and GluR4 complex levels were even linked to memory training, which may be of relevance for understanding molecular memory processes, interpretation of previous work or for design of future AMPA receptor studies.  相似文献   
9.
Our study investigated the association of rare allelic variants with extremes of 24-hour urinary calcium excretion because higher urinary calcium excretion is a dominant risk factor for calcium-based kidney stone formation. We resequenced 40 candidate genes potentially related to urinary calcium excretion in individuals from the Nurses'' Health Studies I & II and the Health Professionals Follow-up Study. A total of 960 participants were selected based on availability of 24-hour urine collection data and level of urinary calcium excretion (low vs. high). We utilized DNA sample pooling, droplet-based target gene enrichment, multiplexing, and high-throughput sequencing. Approximately 64% of samples (n = 615) showed both successful target enrichment and sequencing data with >20-fold deep coverage. A total of 259 novel allelic variants were identified. None of the rare gene variants (allele frequencies <2%) were found with increased frequency in the low vs. high urinary calcium groups; most of these variants were only observed in single individuals. Unadjusted analysis of variants with allele frequencies ≥2% suggested an association of the Claudin14 SNP rs113831133 with lower urinary calcium excretion (6/520 versus 29/710 haplotypes, P value = 0.003). Our data, together with previous human and animal studies, suggest a possible role for Claudin14 in urinary calcium excretion. Genetic validation studies in larger sample sets will be necessary to confirm our findings for rs113831133. In the tested set of candidate genes, rare allelic variants do not appear to contribute significantly to differences in urinary calcium excretion between individuals.  相似文献   
10.
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