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71.
Pedersen LM Terslev L SŁrensen PG Stokholm KH 《Medical oncology (Northwood, London, England)》2000,17(2):117-122
Transcapillary escape rate of albumin was determined in 22 patients with different malignancies. In addition, urinary albumin
excretion rate was measured in 24-h urine samples using a sensitive immunoassay. Increased urinary albumin excretion was defined
as ≥20 μg/min according to conventional standards. Renal glomerular filtration and tubular function was estimated by51Cr-EDTA plasma clearance and urinary beta 2-microglobulin, respectively. Median urinary albumin excretion rate was 15.0 μg/min
(range 6–510 μg/min) and the frequency of increased urinary albumin excretion was 41%. This agrees with other studies showing
increased albuminuria in several types of malignant diseases. Patients with advanced disease (tumour, node, metastasis (TNM)
stage II–IV) had a significantly higher urinary albumin excretion rate than patients with localized disease (TNM stage I).
Serum creatinine, glomerular filtration rate and urinary beta 2-microglobulin were all within normal limits. Median transcapillary
escape rate of albumin was 5.5%/h (range 2–8%/h) and this level is comparable with values in healthy subjects. There was no
significant difference in transcapillary escape rate between patients with elevated urinary albumin excretion and the normoalbuminuric
group. Median value of the absolut outflux of albumin was 10.6 g/h with similar levels in patients with increased urinary
albumin excretion and patients with normoalbuminuria. Our results indicate a high prevalence of minor glomerular dysfunction
with a slightly elevated urinary albumin excretion in patients with malignancies. The normal endothelial function, as estimated
by the transcapillary escape rate of albumin, suggests an overal unaffected capillary permeability and increased urinary albumin
loss appears to be an isolated renal phenomenon in cancer patients. 相似文献
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73.
Objective : To describe the obstetric and perinatal factors, in particular the method of delivery, associated with development of a subgaleal haematoma (SGH) and to determine the outcome of survivors with this type of birth trauma. Methodology : Perinatal and obstetric data were retrospectively reviewed for 37 infants admitted to the neonatal unit of the sole tertiary paediatric referral hospital in Western Australia with an SGH, over a 24 year period from 1970 to 1993. These data were compared to data for all Western Australian births. The long-term outcome was obtained through medical and private paediatric records for 26 of these infants. Results : All except one of the neonates had instrumental deliveries; 89% had a vacuum extractor applied to the head at some stage of delivery compared to 10% of the general population of births in Western Australia. There was also a significantly increased risk of failure of attempted vacuum extraction. Of the cases where a vacuum extraction was attempted, 45% also had forceps applied to the head. Coagulopathy was associated with the severity of the SGH. There was also a high frequency of occurrence (40%) of associated head trauma such as intracranial haemorrhage, skull fracture and cerebral oedema, as well as neonatal encephalopathy (73%). The occurrence of these associated features did not correlate significantly with the severity of SGH. Minor complications of SGH included jaundice and facial bruising. There was an excess mortality associated with SGH; however, the long-term outcome for neonatal survivors with this disorder was good. None of the cases studied subsequently developed cerebral palsy or intellectual disability, and minor neurological sequelae only were documented in four infants. Conclusions : SGH is an uncommon type of birth trauma, and is associated with delivery or attempted delivery by vacuum extraction. The most commonly associated clinical problems were hypovolaemia and coagulopathy. The long-term outcome for neonates with this condition is good. 相似文献
74.
Epithelial cells of the several subtypes that comprise the small-granule cell population of the respiratory system are little studied, partly because adequate silver, monoamine fluorescence and other specific light microscopical preparations have been more difficult to obtain than in the gut and other organs possessing diffuse endocrine systems. Periodic acid-Schiff (PAS) in combination with MacConaill-Solcia's lead hematoxylin has in our hands proven dependable for routine staining of serial 2-m?m glycol methacrylate sections used in mapping the distributions of these cells along the airway. In lungs of mice, hamsters, kittens, and fetal rabbits, typical small-granule cells stain weakly or not at all with lead hematoxylin alone, hence are easily overlooked. PAS adds to the cytoplasm a diffuse magenta coloration; and because it is diastase-resistant, less brilliant than that of mucus but more so than bronchiolar cell secretions, and finer textured than lysosomal staining of other cells present, the effect is to highlight small-granule cells whether solitary or in clusters. Additional PAS staining of basement membranes and lead hematoxylin staining of cilia enhance the combined stain's resolving power. In thyroid gland, parafollicular cells stand out boldly against follicular elements; in small intestine, hematoxylin-positive endocrine cells are well differentiated from absorptive, mucous, and Paneth cells that surround them. Using a complementary monoamine fluorescence technique on plastic sections of lungs from control and 5-hydroxytryptophan-pretreated animals prior to staining, we can show that fluorescent epithelial cells are identical with those stained by PAS-lead hema-toxylin. 相似文献
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78.
Hendler I Goldenberg RL Mercer BM Iams JD Meis PJ Moawad AH MacPherson CA Caritis SN Miodovnik M Menard KM Thurnau GR Sorokin Y 《American journal of obstetrics and gynecology》2005,192(3):882-886
OBJECTIVE: The purpose of this study was to evaluate the relationship between prepregnancy maternal body mass index and spontaneous preterm birth and indicated preterm birth. STUDY DESIGN: This was a secondary analysis of the Maternal-Fetal Medicine Units Network, Preterm Prediction study. Patients were classified into categories that were based on their body mass index. Rates of indicated and spontaneous preterm birth were compared. RESULTS: Five hundred ninety-seven (20.5%) of 2910 women were obese. Obese women had fewer spontaneous preterm births at < 37 weeks of gestation (6.2% vs 11.2%; P < .001) and at < 34 weeks of gestation (1.5% vs 3.5%; P = .012). Women with a body mass index of < 19 kg/m2 had 16.6% spontaneous preterm birth, with a body mass index of 19 to 24.9 kg/m 2 had 11.3% spontaneous preterm birth, with a body mass index of 25 to 29.9 kg/m2 had 8.1% spontaneous preterm birth, with a body mass index of 30 to 34.9 kg/m2 had 7.1% spontaneous preterm birth, and with a body mass index of > or = 35 kg/m2 had 5.2% spontaneous preterm birth (P < .0001). Indicated delivery was responsible for an increasing proportion of preterm births with increasing body mass index (P = .001). Obese women had lower rates of cervical length < 25 mm (5% vs 8%; P = .012). Multivariable regression analysis confirmed a lower rate of spontaneous preterm birth in obese gravid women (odds ratio, 0.57; 95% CI, 0.39-0.83; P = .003). CONCLUSION: Obesity before pregnancy is associated with a lower rate of spontaneous preterm birth. 相似文献
79.
Strength at the extracellular matrix-muscle interface 总被引:1,自引:0,他引:1
Grounds MD Sorokin L White J 《Scandinavian journal of medicine & science in sports》2005,15(6):381-391
Mechanical force is generated within skeletal muscle cells by contraction of specialized myofibrillar proteins. This paper explores how the contractile force generated at the sarcomeres within an individual muscle fiber is transferred through the connective tissue to move the bones. The initial key point for transfer of the contractile force is the muscle cell membrane (sarcolemma) where force is transferred laterally to the basement membrane (specialized extracellular matrix rich in laminins) to be integrated within the connective tissue (rich in collagens) before transmission to the tendons. Connections between (1) key molecules outside the myofiber in the basement membrane to (2) molecules within the sarcolemma of the myofiber and (3) the internal cytoplasmic structures of the cytoskeleton and sarcomeres are evaluated. Disturbances to many components of this complex interactive system adversely affect skeletal muscle strength and integrity, and can result in severe muscle diseases. The mechanical aspects of these crucial linkages are discussed, with particular reference to defects in laminin-alpha2 and integrin-alpha7. Novel interventions to potentially increase muscle strength and reduce myofiber damage are mentioned, and these are also highly relevant to muscle diseases and aging muscle. 相似文献
80.