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991.
We present 19 ray lengthenings in 14 patients done with a small external fixator. In six cases the thumb was lengthened and in the other 13 cases, other digital rays. The most frequent reason for lengthening was an amputation sustained in a work accident. All the lengthenings were done by an osteotomy and subsequent gradual distraction with a small external fixator. The mean lengthening achieved was 20 mm (range, 0-32). An iliac-crest graft was needed in nine cases, corrective osteotomy in five cases and a deepening of the web in the six cases of thumb lengthening. In five cases an additional technique was needed to achieve bony consolidation. We have analysed the functional results and the ability to perform activities of daily living and resume employment. Although most of the patients had multiples injuries, the results have been very favourable, achieving a very high level of patient satisfaction.  相似文献   
992.
A large number of trafficking steps occur between the last compartment of the Golgi apparatus (TGN) and the vacuole of the yeast Saccharomyces cerevisiae. To date, two intracellular routes from the TGN to the vacuole have been identified. Carboxypeptidase Y (CPY) travels through a prevacuolar/endosomal compartment (PVC), and subsequently on to the vacuole, while alkaline phosphatase (ALP) bypasses this compartment to reach the same organelle. Proteins resident to the TGN achieve their localization despite a continuous flux of traffic by continually being retrieved from the distal PVC by virtue of an aromatic amino acid-containing sorting motif. In this study we report that a hybrid protein based on ALP and containing this retrieval motif reaches the PVC not by following the CPY sorting pathway, but instead by signal-dependent retrograde transport from the vacuole, an organelle previously thought of as a terminal compartment. In addition, we show that a mutation in VAC7, a gene previously identified as being required for vacuolar inheritance, blocks this trafficking step. Finally we show that Vti1p, a v-SNARE required for the delivery of both CPY and ALP to the vacuole, uses retrograde transport out of the vacuole as part of its normal cellular itinerary.  相似文献   
993.
The effects of feeding different amounts of colostrum or only milk replacer and the effects of Long-R3-IGF-I (administered s.c. or orally; 50 microg/[kg BW x d] for 7 d), and of s.c. injected recombinant bovine GH (rbGH; 1 mg/[kg BW x d] for 7 d) on small intestinal mucosal morphology in newborn calves were studied by histomorphometry. Neonatal calves fed colostrum six times exhibited greater (P < .01) villus circumferences, areas, and heights in total small intestine and especially in the duodenum than calves fed only milk replacer. Furthermore, villus circumferences and areas in total small intestine were greater (P < .05) in calves fed colostrum once than in calves fed no colostrum. Villus size in total small intestine was smaller (P < .05) in rbGH-treated than in control calves; jejunum villus circumferences and heights were especially reduced (P < .05). Crypt depths in ileum were greater (P < .05) in rbGH-treated calves. In conclusion, prolonged colostrum supply significantly enhanced small intestinal villus size in neonatal calves. In contrast, Long-R3-IGF-I had no significant influence on small intestinal morphology, and rbGH in supraphysiological amounts even reduced small intestinal mucosal variables after 1 wk of treatment. The study demonstrated enhanced postnatal development of the gastrointestinal tract by prolonged colostrum feeding, but not by Long-R3-IGF-I or GH.  相似文献   
994.
INTRODUCTION: Problems that may arise in resin composite Class 2 restorations include microleakage and postoperative sensitivity. However, limited in-vivo research is conducted to evaluate these processes. AIM: The aim of this study was to assess postoperative sensitivity, microleakage and the pooling of adhesives in relation to Class 2 box-type composite restorations placed in vivo using various adhesive systems and application techniques. MATERIALS AND METHODS: One hundred and forty-four Class 2 box restorations were placed in the mesial and distal surfaces of 72 premolar teeth in-vivo using one of three combinations of adhesive systems and three filling techniques. After 6 weeks of clinical service postoperative sensitivity was recorded. The teeth were then extracted, immersed in a dye solution and sectioned. Microleakage and pooling of the adhesive was recorded. Statistical analysis involved logistic regression and chi2 tests to identify differences between groups at p < 0.05. RESULTS: Of the 144 restorations, 65 showed minimal cervical leakage in enamel, 5 suffered leakage into dentin and 74 were free of microleakage. No statistically significant differences were found in cervical microleakage between the adhesive systems or between filling procedures. Occlusal microleakage in the enamel was present in 16 of the 160 restorations. Liner Bond 2 restorations leaked significantly more at the occlusal surface (p < 0.05). Pooling of the adhesive was significantly less when PhotoBond was used. No spontaneous postoperative sensitivity was reported. Twenty-eight restorations were sensitive to loading. Postoperative sensitivity was significantly less in patients with Liner Bond 2 restorations. CONCLUSIONS: The adhesive systems used in this study showed minimal leakage into dentin in vivo. Using Liner Bond 2, restorations exhibited more occlusal leakage but were significantly less sensitive to loading.  相似文献   
995.
Mobilization of bone marrow eosinophils is a critical early step in their trafficking to the lung during allergic inflammatory reactions. We have shown previously that the cytokine interleukin (IL)-5, generated during an allergic inflammatory reaction in the guinea pig, acts systemically to mobilize eosinophils from the bone marrow. Here, we have investigated the mechanisms underlying this release process. Examination by light and electron microscopy revealed the rapid migration of eosinophils from the hematopoietic compartment and across the bone marrow sinus endothelium in response to IL-5. Using an in situ perfusion system of the guinea pig hind limb, we showed that IL-5 stimulated a dose-dependent selective release of eosinophils from the bone marrow. Eosinophils released from the bone marrow in response to IL-5 expressed increased levels of beta2 integrin and a decrease in L-selectin, but no change in alpha4 integrin levels. A beta2 integrin-blocking antibody markedly inhibited the mobilization of eosinophils from the bone marrow stimulated by IL-5. In contrast, an alpha4 integrin blocking antibody increased the rate of eosinophil mobilization induced by IL-5. In vitro we demonstrated that IL-5 stimulates the selective chemokinesis of bone marrow eosinophils, a process markedly inhibited by two structurally distinct inhibitors of phosphatidylinositol 3-kinase, wortmannin and LY294002. Wortmannin was also shown to block eosinophil release induced by IL-5 in the perfused bone marrow system. The parallel observations on the bone marrow eosinophil release process and responses in isolated eosinophils in vitro suggest that eosinophil chemokinesis is the driving force for release in vivo and that this release process is regulated by alpha4 and beta2 integrins acting in opposite directions.  相似文献   
996.
It is unknown whether antibiotic susceptibility testing of antral isolates alone is representative of Helicobacter pylori susceptibility. We aimed to determine: (i) the prevalence of metronidazole- and clarithromycin-resistant strains in infected dyspeptic patients; and (ii) whether there is consistency in the susceptibility to metronidazole and clarithromycin among isolates cultured from different gastric sites. Antral, body and fundus biopsies were taken from 242 consecutive patients and cultured on blood agar under micro-aerophilic conditions for 5-7 days. Isolates from 66 patients (13 had one, 15 had two and 38 had three isolates) were tested for susceptibility to metronidazole and clarithromycin using previously validated disc diffusion tests. Of the 66 patients, 42 (64%) had strains resistant to metronidazole while four (6.1%) had clarithromycin-resistant strains. The prevalence of metronidazole resistance was not significantly different between men and women (65% vs 60%) or across different age groups. In five (9.4%) of the 53 patients with multiple isolates, discrepant results for metronidazole susceptibility were observed: susceptible antral and body isolates but resistant fundus isolates in two cases and susceptible antral isolates but resistant body and fundus isolates in the others. Clarithromycin susceptibilities were consistent among the isolates cultured from different gastric sites in all patients. It is concluded that metronidazole-resistant strains of H. pylori are common while clarithromycin-resistant strains are rare. Metronidazole susceptibility testing of antral isolates does not appear to be representative of isolates from the body and fundus in a subset of patients.  相似文献   
997.
This multicenter, randomized, double-masked, parallel-group, 24-week clinical study compared the efficacy of the combination of azelaic acid 20% cream and glycolic acid 15% or 20% lotion with hydroquinone 4% in the treatment of facial hyperpigmentation in darker-skinned patients. At week 24, overall improvement and reduction in lesion area, pigmentary intensity, and disease severity were comparable in the two treatment groups. At some visits, patients treated with an azelaic/glycolic acid combination had slightly greater levels of peeling, burning, stinging, or dryness than did patients treated with hydroquinone, although scores for cutaneous signs and symptoms were always low. The present study demonstrated that the combination of azelaic acid 20% cream and glycolic acid 15% or 20% lotion was as effective as hydroquinone 4% cream in the treatment of hyperpigmentation in darker-skinned patients, with only a slightly higher rate of mild local irritation. These findings suggest that the addition of glycolic acid to azelaic acid treatment for hyperpigmentation is an appropriate alternative in selected darker-skinned patients.  相似文献   
998.
Radioactive iodine, in the form of iodine-131, behaves similarly to stable iodine in small quantities, thus resulting in a radiation dose to the thyroid. Under the Medical Internal Radiation Dosimetry Committee formulation for radiation dose calculation to an organ, the resulting dose to the thyroid gland is dependent on the organ mass, its isotope uptake and the effective half-life of the element in the gland. Traditionally, values have been used for these parameters which, in some cases, were determined some decades previous. Iodine supply is a primary contributor to correct thyroid function and ultimately these values of mass, uptake and half-life. Recently, new data have become available on iodine kinetics throughout Europe. Here, the influence of the highly variable iodine supply in Europe on projected thyroid doses is determined. Thyroid mass values ranged from 9 g (Sweden) to 28 g (Poland) while uptake measurements were found to range from 18% (Finland) to approximately 60% (Germany and Poland). Resulting dose estimates ranged from 0.5 Gy MBq-1 (Finland) injested to 1.3 Gy MBq-1 (Czechoslovakia) injested. It was also found that among European populations the highest dose burden was to those populations with mild iodine deficiency. The results show that the use of generic metabolic data for the thyroid can lead to a misrepresentation of the absorbed dose to the thyroid. Thus, the data presented provide a better reflection of the actual thyroid dose following ingestion of iodine-131 for European countries.  相似文献   
999.
AIM: To determine if a weaning regimen on flow driver continuous positive airway pressure (CPAP) would decrease the number of ventilator days but increase the number of CPAP days when compared with a rescue regimen. METHODS: Fifty eight babies of 24-32 weeks gestation with respiratory distress syndrome (RDS) were studied prospectively. After extubation they were randomly allocated to receive CPAP for 72 hours (n = 29) according to a weaning regimen, or were placed in headbox oxygen and received CPAP only if present "start CPAP" criteria were met (n = 29, rescue group). RESULTS: There was no difference in successful extubation at 72 hours, 1 and 2 weeks, between the groups in terms of the number of reventilation episodes, reventilation days, or in total days of CPAP. Birthweight, gestational age, race, day of first extubation, antenatal or postnatal steroids, patent ductus arteriosus status and maximal mean airway pressure used were of no value in predicting success or failure at 72 hours, 1, or 2 weeks. CONCLUSION: The weaning regimen did not decrease the number of ventilator days or days on CPAP compared with the rescue regimen. The rescue regimen on flow driver CPAP seems to be a safe and effective method of managing a baby of 24-32 weeks gestation who has been ventilated for RDS or immature lung disease.  相似文献   
1000.
BACKGROUND: In 1968 the first antenatal diagnosis of Down's syndrome was made and screening on the basis of selecting women of advanced maternal age for amniocentesis was gradually introduced into medical practice. In 1983 it was shown that low maternal serum alpha fetoprotein (AFP) was associated with Down's syndrome. Later, raised maternal serum human chorionic gonadotrophin (hCG), and low unconjugated oestriol (uE3) were found to be markers of Down's syndrome. In 1988 the three biochemical markers were used together with maternal age as a method of screening, and this has been widely adopted. PRINCIPLES OF ANTENATAL SCREENING FOR DOWN'S SYNDROME: Methods of screening need to be fully evaluated before being introduced into routine clinical practice. This included choosing markers for which there is sufficient scientific evidence of efficacy, quantifying performance in terms of detection and false positive rates, and establishing methods of monitoring performance. Screening needs to be provided as an integrated service, coordinating and managing the separate aspects of the screening process. SERUM MARKERS AT 15-22 WEEKS OF PREGNANCY: A large number of serum markers have been found to be associated with Down's syndrome between 15 and 22 weeks of pregnancy. The principal markers are AFP, hCG or its individual subunits (free alpha- and free beta-hCG), uE3, and inhibin A. Screening performance varies according to the choice of markers used and whether ultrasound is used to estimate gestational age (table 1). When an ultrasound scan is used to estimate gestational age the detection rate for a 5% false positive rate is estimated to be 59% using the double test (AFP and hCG), 69% using the triple test (AFP, hCG, uE3), and 76% using the quadruple test (AFP, hCG, uE3, inhibin A), all in combination with maternal age. Other factors that can usefully be taken into account in screening are maternal weight, the presence of insulin dependent diabetes mellitus, multiple pregnancy, ethnic origin, previous Down's syndrome pregnancy, and whether the test is the first one in a pregnancy or a repeat. Factors such as parity and smoking are associated with one or more of the serum markers, but the effect is too small to justify adjusting for these factors in interpreting a screening test. URINARY MARKERS AND FETAL CELLS IN MATERNAL BLOOD: Urinary beta-core hCG has been investigated in a number of studies and shown to be raised in pregnancies with Down's syndrome. This area is currently the subject of active research and the use of urine in future screening programmes may be a practical possibility. Other urinary markers, such as total oestriol and free beta-hCG may also be of value. Fetal cells can be identified in the maternal circulation and techniques such as fluorescent in situ hybridisation can be used to identify aneuploidies, including Down's syndrome and trisomy 18. This approach may, in the future, be of value in screening or diagnosis. Currently, the techniques available do not have the performance, simplicity, or economy needed to replace existing methods. DEMONSTRATION PROJECTS: Demonstration projects are valuable in determining the feasibility of screening and in refining the practical application of screening. They are of less value in determining the performance of different screening methods. Several demonstration projects have been conducted using the triple and double tests. In general, the uptake of screening was about 80%. The screen positive rates were about 5-6%. About 80% of women with positive screening results had an invasive diagnostic test, and of those found to have a pregnancy with Down's syndrome, about 90% chose to have a termination of pregnancy. ULTRASOUND MARKERS AT 15-22 WEEKS OF PREGNANCY: There are a number of ultrasound markers of Down's syndrome at 15-22 weeks, including nuchal fold thickness, cardiac abnormalities, duodenal atresia, femur length, humerus length, pyelectasis, and hyperechogenic bowel. (ABSTRA  相似文献   
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