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11.
The long term outcome of open total and partial meniscectomy related to the quantity and site of the meniscus removed 总被引:1,自引:0,他引:1
Summary Two hundred patients were randomly selected for either a partial or a total meniscectomy for a meniscal tear during open operation. They were followed for a median of 7.8 years after operation. After partial meniscectomy, posterior horn tears had the worst outcome, but this was only apparent when more than two-thirds of the meniscus had been removed. The amount of meniscal tissue excised was inversely related to the function of the knee, except with bucket-handle tears treated by partial meniscectomy. Patients with bucket-handle, anterior and posterior horn tears had similar functional results after total meniscectomy. Preservation of the peripheral rim of the meniscus following partial meniscectomy produces the best functional results.
Résumé Deux cents patients atteints de lésion méniscale ont été répartis en cours d'opération, de façon randomisée, entre méniscectomie partielle et méniscectomie totale. Ces patients ont été revus, au dernier examen, de 6.3 à 9.8 ans après l'intervention (à 7.8 ans en moyenne). Après méniscectomie partielle c'étaient les lésions de la corne postérieure qui avaient les moins bons résultats fonctionnels, mais les différences de résultat selon les types de lésion n'étaient observées que lorsque plus d'un tiers de la surface méniscale avait été réséquée. La quantité de tissu méniscal enlevé était inversement proportionnelle à la qualité de la fonction du genou, sauf dans les déchirures en anse de seau traitées par méniscectomie partielle. Ces lésions étaient celles où la plus forte proportion de tissu méniscal avait été réséquée, mais dont les résultats fonctionnels étaient meilleurs que ceux des lésions de la corne postérieure. Les patients présentant des anses de seau, des lésions de la corne antérieure ou de la corne postérieure, avaient des résultats fonctionnels similaires après méniscectomie totale. La conservation de la périphérie du ménisque après méniscectomie partielle est le facteur essentiel d'un bon résultat fonctionnel post-opératoire.相似文献
12.
Genotype-phenotype correlation for nucleotide substitutions in the IgII- IgIII linker of FGFR2 总被引:6,自引:3,他引:3
13.
Uroscopy in the 21st century: high-field NMR spectroscopy 总被引:1,自引:1,他引:0
Neild GH; Foxall PJ; Lindon JC; Holmes EC; Nicholson JK 《Nephrology, dialysis, transplantation》1997,12(3):404-417
From the experiments described, it can be seen that there are different
research approaches that can be taken and these are summarized in Table 1.
Whereas much scientific research is principally hypothesis led, there
remains, nevertheless, an important place for exploratory research. High
resolution NMR can measure, directly and simultaneously, a wide range of
endogenous metabolites in biological fluids and has the unique capability
of providing structural information on the metabolites detected. It has
proved to be a powerful research tool with which to study inherited
metabolic diseases, renal disease, drug metabolism, and toxicity, and can
be used to monitor the effects of drug therapy. For instance, by using a
library of experimental toxins one can map the metabolic profile of
site-specific nephron injury. With this approach in man one could
eventually take an unknown disease such as Balkan nephropathy and predict
the initial site of tubular injury, the mode of injury and therefore the
kind of toxin capable of producing that injury. NMR spectroscopic
techniques are still advancing rapidly, with ever increasing sensitivity
and sophistication of NMR pulse sequences to enhance structural elucidation
in complex mixtures. Given the advances in directly coupled HPLC-NMR and
even HPLC-NMR-mass spectroscopy it is likely that these technologies in
conjunction with pattern recognition will make major contribution to our
understanding of renal processes and provide new diagnostic insights in the
21st century.
相似文献
14.
M Brune L Rossander-Hultén L Hallberg A Gleerup A S Sandberg 《The Journal of nutrition》1992,122(3):442-449
Iron absorption was measured from five kinds of bread made from various types of flour and fermented in different ways in order to obtain a wide variation in the content of fiber, phytate (inositol hexaphosphate) and its degradation products, inorganic phosphate and inositol phosphates with fewer numbers of phosphate groups (inositol pentaphosphate through monophosphate). Each experiment had 9-10 subjects and, in each subject, iron absorption was measured from control rolls made from low extraction wheat flour and one kind of test roll using two different radioiron tracers: 55Fe and 59Fe. The inhibition of iron absorption was closely related to the content of phytate-phosphorous as determined using the AOAC method, and to the sum of the tri- through hexaphosphate groups as determined using the HPLC method. As an example, prolonged fermentation of whole-rye bread reduced total inositol phosphates to the same amount as in the control rolls and increased fractional iron absorption to the same high level, in spite of a fiber content five times as great. The results strongly suggest that the inhibitory effect of bran on iron absorption is due to its content of phytate and other inositol phosphates present after fermentation, rather than to its content of fiber or other constituents. Thus, effective fermentation will increase the bioavailability of iron in whole-meal bread. 相似文献
15.
Introduction : Hypertrophic scar is a devastating sequel to burns and other tangential skin injuries. It follows deep dermal injuries and does not occur after superficial injuries. Nitric oxide (NO) plays many important roles in wound healing from inflammation to scar remodeling. Studies have shown that expression of nitric oxide synthase and nitric oxide production are decreased in human hypertrophic scar. However little is known about NO involvement in the early stages of hypertrophic scarring, because of the lack of an animal model. It was recently reported that the female red Duroc pig (FRDP) makes thick scar, which is similar to human hypertrophic scar. We hypothesized that NO production in wounds on the female, red Duroc pig is similar to that of human hypertrophic scar and that NO involvement in deep wounds is different from that in superficial wounds. Methods : Superficial (0.015” to 0.030”) and deep (0.045” to 0.060”) wounds were created on the backs of four FRDPs. Biopsies were collected at weeks 1.5, 4, 8 and 21 post wounding including samples of uninjured skin. Nitric oxide levels were measured with the Griess reaction assay and normalized with tissue protein level. Results : Superficial wounds healed with an invisible scar whereas the deep wounds healed with scar resembling mild hypertrophic scar. The thickness of the scars from the deep wounds was significantly greater than uninjured skin and healed superficial wounds (p < 0.01). NO levels were increased at 1.5 weeks in deep wounds compared to superficial wounds and uninjured skin (p < 0.05). At 8 weeks, NO levels in deep wounds had returned to the level of uninjured tissue and superficial wounds. By 21 weeks, NO levels had decreased significantly when compared to superficial wounds (p < 0.01). There were no differences in NO levels between uninjured skin and superficial wounds at any time point (p > 0.05). Conclusions : NO production is similar in late, deep wounds on the female, red Duroc pig to that reported in the literature for human hypertrophic scar further validating this animal model. NO production is quite different after deep wounds as compared to superficial wounds in the FRDP. Early elevation in nitric oxide production might account for excessive inflammation in deep wounds that become thick scars in the FRDP. Nitric oxide regulators and effects at early stages of scar formation should be elucidated further and the FRDP appears to be a useful model. 相似文献
16.
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18.
Unrelated patients with achromatopsia, macular degeneration with onset under age 50 years, cone degeneration or dysfunction, cone-rod degeneration, or macular malfunction were screened for mutations in the three genes known to be associated with achromatopsia: the GNAT2 gene encoding the alpha subunit of cone transducin and the CNGA3 and CNGB3 genes encoding the alpha and beta subunits of the cone cGMP-gated cation channel. We found no examples of patients with GNAT2 mutations. Out of 36 achromats, 12 (33%) had mutations in CNGA3 (13 different mutations including five novel mutations) and 12 (33%) had mutations in CNGB3 (six different mutations including four novel mutations). All achromats with CNG mutations had residual, presumably cone function as determined by computer-averaged 30-Hz electroretinograms (ERGs). There was considerable variability in acuity and color vision, with most patients having acuities of 20/200-20/400 and complete absence of color perception, and others having acuities of 20/25-20/40 and some color vision. Two pseudodominant achromatopsia cases were uncovered, both with CNGA3 mutations, including one family in which some compound heterozygotes with achromatopsia mutations were clinically unaffected. We found two novel CNGB3 changes in three patients with juvenile macular degeneration, a phenotype not previously associated with mutations in the cone channel subunits. These patients had subnormal acuity (20/30-20/60), normal to subnormal color vision, and normal to subnormal full-field cone ERG amplitudes. Our results indicate that some patients with channel protein mutations retain residual foveal cone function. Based on our findings, CNGB3 should be considered as a candidate gene to be evaluated in patients with forms of cone dysfunction, including macular degeneration. 相似文献
19.
Determination of optimal cryoprotectants and procedures for their addition and removal from human spermatozoa 总被引:9,自引:7,他引:9
The objective was to test the hypothesis that the optimal cryoprotective
agent for cryopreservation of human spermatozoa would be a solute for which
cells have the highest plasma membrane permeability, resulting in the least
amount of volume excursion during its addition and removal. To test this
hypothesis, theoretical simulations were performed using membrane
permeability coefficients to predict optimal procedures for the addition
and removal of a cryoprotectant. Simulations were performed using data from
four different cryoprotectants: (i) glycerol, (ii) dimethyl sulphoxide,
(iii) propylene glycol and (iv) ethylene glycol. Thermodynamic formulations
were applied to determine approaches for the addition and removal of 1 M
and 2 M final concentrations of cryoprotectant, allowing the spermatozoa to
maintain a cell volume within their osmotic tolerance limits. Based on
these data, ethylene glycol was predicted to be optimal for minimizing
volume excursions among the solutes evaluated. These predictions were then
experimentally tested using glycerol as the control cryoprotectant and
ethylene glycol as the experimental cryoprotectant. The results indicate
that there was a higher (P < 0.05) recovery of motile spermatozoa after
cryopreservation when using 1 M ethylene glycol than with 1 M glycerol,
supporting the hypothesis that use of the cryoprotectant for which the cell
has the highest permeability will result in higher cell survival.
相似文献
20.
Donor insemination: Dutch parents' opinions about confidentiality and donor anonymity and the emotional adjustment of their children 总被引:1,自引:4,他引:1
Brewaeys A; Golombok S; Naaktgeboren N; de Bruyn JK; van Hall EV 《Human reproduction (Oxford, England)》1997,12(7):1591-1597
Results from a comparative study investigating 38 donor insemination (DI)
Dutch families with 4-8 year old children are presented. The aims of this
study were to investigate parents' opinions on the issues of
confidentiality and donor anonymity, to assess the emotional development of
the children, and to examine in DI families the association between secrecy
with regard to the use of a donor and the emotional adjustment of the
children. The DI families were compared to families with a child conceived
by in-vitro fertilization (IVF) and to families with a naturally conceived
child. Secrecy appeared to be associated with DI and not with IVF: 74% of
the DI parents intended not to inform the child about the way in which
she/he was conceived, whereas none of the IVF parents intended to keep the
secret. Only one set of DI parents and two sets of IVF parents had actually
told the child. As to donor anonymity, a spread of opinions appeared among
DI parents; 57% preferred an anonymous donor, 31% would have liked non-
identifying information about the donor, 9% preferred the donor's identity
to be registered and 3% remained unsure. Parents' major concern was to know
more about the medical/genetic background of the donor. Mothers and fathers
in the DI families differed in their opinions concerning the issues of
confidentiality and donor anonymity: fathers, more often than mothers, were
secretive with regard to the use of a donor and husbands, more often than
their wives, were in favour of donor anonymity. With regard to the
emotional development of the children, more emotional/behavioural problems
were revealed among DI children than among children who were naturally
conceived. No association was found between secrecy and the
emotional/behavioural adjustment of the children.
相似文献