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641.
WJ Harries  AA Amis   《The Knee》1994,1(4):209-215
This paper describes the surgical method and instruments for placing and anchoring the Apex polyester fibre anterior cruciate ligament (ACL) reconstruction. It then reviews the early clinical findings and describes recent developments. At the time of review, 172 Apex replacements had been implanted in the UK in arthroscopically proven chronic ACL-deficient knees. These had been inserted at eight centres since 1987, and follow up was by a single observer assessing patients by questionnaire, clinical examination, stress X-ray and KT 1000 arthrometer. Patients less than 12 months from surgery were excluded, leaving 95 with a mean follow up of 27 months (range 13 to 66 months) on whom results are based. Assessment showed improved stability after operation and the Apex implant appears to provide a reliable method of stabilizing the ACL deficient knee within the confines of this short-term review. The authors feel that further trials are justified.  相似文献   
642.
We have shown recently that adenosine deaminase (ADA)-deficient mice die perinatally with severe liver cell degeneration. In addition to enzyme substitution, we report the restoration of viability through introduction of the human ADA gene. The ADA gene is subject to complex developmental and tissue-specific regulation. To include the cis- regulatory elements necessary for correct regulation of the human ADA gene, a large transgenic locus constituting the human ADA gene with 10 kb of 5' and 4 kb of 3' flanking sequences was generated by co- injection of two overlapping DNA fragments into murine zygotes. Probably as a result of extrachromosomal (homologous) recombination between the fragments, one of the two transgenic lines contained a reconstituted, functional human ADA gene. As in man, human ADA expression generally was low in these transgenic mice, but high in the thymus, spleen and gastro-duodenal part of the gut. Apparently, all cis- regulatory elements essential for a human expression pattern were incorporated in the transgene and were functional in the murine background. Similarly to man, the upper alimentary tract of the transgenic mice revealed low human ADA activity in contrast to extremely high levels of murine ADA. The human gene probably lacks the cis-regulatory elements that target high level murine ADA expression to the murine upper alimentary tract. ADA-deficient mice rescued by introduction of the human ADA transgene appeared histologically and immunologically normal. Apparently, human ADA can complement murine ADA in all tissues, even in the epithelium of the upper alimentary tract where human ADA activity is as much as 70-fold lower than murine ADA activity in wild-type mice. Clearly, the lethal phenotype of ADA- deficient mice is due to the absence of ADA.   相似文献   
643.
Placental protein 14 (PP14) is a glycoprotein which is secreted by secretory phase endometrium and decidua in women. Despite the suggestion that PP14 is involved in the process of endometrial maturation for blastocyst implantation, our understanding in this regard is poor. In the present study, the concentrations and distribution patterns of immunodetectable PP14 in the endometrium during proliferative and secretory phases of normal ovulatory menstrual cycles, as well as in implantation stage endometrium in naturally mated ovulatory cycles with or without early luteal phase mifepristone treatment, were investigated using the rhesus monkey as a primate model. Immunopositive PP14 was observed mainly in epithelial cells of glands and it was detected in one major immunopositive band at Mr 28 kDa in tissue homogenate and spent medium. The area of immunopositive precipitation of PP14 in glands was minimal in follicular phase endometrium, and was higher (P < 0.01) in early, mid- and late luteal phase endometrium compared with that in pre- and periovulatory phases of the cycle, but there was no change in its area profile in the glandular compartment throughout the luteal phase. Immunopositivity for PP14 in luminal contents of gland displayed an increasing profile from early to late secretory phases. Thus, the concentrations and the distribution of immunodetectable PP14 in luteal phase endometrium of the rhesus monkey showed marked similarity with those of human endometrium during the natural menstrual cycle. Although there was no marked change in the band characterstics for the protein in implantation stage endometrium following early luteal phase mifepristone treatment, it was markedly decreased (P < 0.01) in tissue homogenate and in vitro spent medium along with a lesser (P < 0.02) degree of immunoprecipitation in the glands in implantation stage samples of mifepristone treatment group compared with that in control group samples. Thus, the contragestional effect of early luteal phase mifepristone treatment appears to be associated with a decrease in the concentration of immunodetectable PP14 in implantation stage endometrial glands and its secretion in the rhesus monkey. It remains to be seen whether this decline is caused from direct antiprogesterone action on endometrial glands during progesterone dominance, or secondarily from associated retarded development of endometrium.   相似文献   
644.
A simple co-culture bioassay system was used to investigate whether or not the anatomical origin affected the ability of epithelial cells from the human uterine (Fallopian) tube to 'bind' spermatozoa. This study was also used to identify some of the factors which may be involved in the regulation of sperm-epithelial interactions in vitro by comparing different tissue culture models and assessing the effect of oestradiol concentration. Epithelial explants harvested from different regions of human uterine tubes were co-incubated with a known concentration of motile donor spermatozoa. All results were adjusted to reflect a standard sperm concentration of 5 x 10(6)/ml. More spermatozoa associated per field of isthmic compared to ampullary epithelium [isthmus 9.5 +/- 0.9, ampulla 7.1 +/- 0.7 (mean +/- SEM); n = 36, P < 0.05, ANOVA] and cells from post-menopausal patients had an apparently reduced ability to bind spermatozoa [isthmus 5.5 +/- 2.0, ampulla 4.3 +/- 1.4 (mean +/- SEM); n = 4]. Neither menstrual cycle stage nor addition of mid-cycle concentrations of 17beta-oestradiol (750 pmol/l) affected the number of spermatozoa which bound to epithelium from either tubal region. In addition, the number of spermatozoa which bound per field of polarized explants was greater (P < 0.05) than that bound to dissociated primary and passaged epithelial cell monolayers. This report is the first to provide evidence suggestive of a role for sperm- epithelial binding in the formation of an isthmic sperm reservoir in the human uterine tube. Results also indicate that oestrogen is not involved in the regulation of these interactions, and that cell polarity is an important factor for such associations in vitro.   相似文献   
645.
646.
ABSTRACT. A study was performed on a Danish school population to obtain reference values of the following serum lipids: total lipid, phospholipid, cholesterol, glycerol and triglyceride. 92 % of 630 children participated, but 23 were excluded following clinical examination. Thus values are given for 301 girls and 274 boys aged 8 to 17 years.  相似文献   
647.
Abstract. A study was performed on a Danish school population to obtain reference values of the following serum lipids: total lipid, phospholipid, cholesterol, glycerol and triglyceride. 92% of 630 children participated, but 23 were excluded following clinical examination. Thus values are given for 301 girls and 274 boys aged 8 to 17 years.  相似文献   
648.
The effect of continuous positive airway pressure (CPAP) on lung mechanics was investigated in 12 babies after operation for severe congenital heart disease. At the time of study all babies were receiving or being weaned from ventilatory support and had abnormally low lung volume or compliance. During CPAP there was a fall in the pulmonary resistance which, with a slight decrease in minute ventilation, resulted in a significant decrease in the work of breathing. It is suggested that lowering the oxygen cost of breathing may contribute to the improvement in arterial oxygenation seen when CPAP is used.  相似文献   
649.
Aims: To estimate the incidence and clinical characteristics in hospital admissions due to dehydration or undernutrition and their laboratory evaluation and treatment outcome in exclusively breastfed infants.
Methods: All hospital admissions during the first 3 months of life assessed by the Dutch Paediatric Surveillance Unit (DPSU) between mid 2003 and mid 2005.
Results: Nationwide 158 cases reported, correspond to an incidence of 58/y/100 000 breastfed infants; it is lower for severe dehydration at risk for hypernatraemia; 20/y/100 000. Sixty-five per cent of cases were <2 weeks old, their median weight loss was 9.3% and median age at admission 5 days; Serum sodium value was measured in only 12% of all cases. Insufficient volume intake and inadequate growth were most frequently reported (61% and 41%). Lethargy, jaundice or clinical dehydration was scored in 11–25%, seizures or shock in 3%. A breast pump at home was used in only 31%. In the hospital breast pumps were available (82%) as lactation consultants (73%). For treatment 65% was offered formula, in 30% by nasogastric drip. Most admissions lasted up to 3 days, all recovered fully and 33% were breastfed exclusively at discharge.
Conclusion: The incidence of severe dehydration in the Netherlands is relatively low. With extended use of breast pumps at home it could be lower. To prevent complications, we recommend applying a reference weight chart, a full clinical examination and more extensive screening of serum sodium and glucose.  相似文献   
650.
Headache is a common, but rarely voiced, complaint during space flights, usually attributed to space motion sickness (SMS). We used a specifically designed questionnaire based on the criteria of the International Classification of Headache Disorders, 2nd edn (ICHD-II). Of the 16 male and one female astronauts who participated in the survey, 12 (71%) reported having experienced at least one headache episode while in space, whereas they had not suffered from headache when on earth. There were in total 21 space headache episodes, of moderate to severe intensity in 71%. In two astronauts (12%) the headache and associated symptoms would match the ICHD-II criteria for migraine and in three (18%) astronauts for tension-type headache; in 12 (70%) astronauts the headache was non-specific. The vast majority of headache episodes (76%) were not associated with symptoms of SMS. We conclude that space flights may trigger headaches without other SMS symptoms in otherwise 'super-healthy' male subjects. We propose to classify space headache as a separate entity among the secondary headaches attributed to disorders of homeostasis.  相似文献   
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