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排序方式: 共有10000条查询结果,搜索用时 421 毫秒
941.
A patient with Graves' disease had a symptomatic thrombocytopathy during periods of remission. When euthyroid, she noticed bruising, petechiae, and epistaxis. Hemostatic abnormalities included prolongation of the bleeding time by aspirin, reduced platelet retention (a second-phase defect), and abnormal thrombin-induced aggregation and serotonin release. When hyperthyroid, bleeding symptoms resolved, and platelet function returned to normal. These observations suggest that mild bleeding disorders may be influenced either directly or indirectly by thyroid hormone levels. 相似文献
942.
Human subjects maintained isometric plantar or dorsal flexions of the ankle in a matching task. H-reflexes of different sizes were superimposed on the steady activity. The peak-to-peak amplitude of the reflexes was measured on the electromyogram (EMG) of the soleus muscle. The size of the corresponding muscle contractions was determined on the isometric torque signal in relation to the maintained flexion force. The EMG-torque relation which was defined as the reflex muscle contraction as a function of the EMG reflex signal approximated a square root function for a given steady contraction level. It was not modulated by steady dorsal flexions, but it decreased continuously with stronger plantar steady torques. This dependence was caused by the silent period following the reflex discharge. Since the reflex discharge and the silent period were near in time to the duration of the contraction, the silent period had a direct effect on the reflex contraction amplitude. 相似文献
943.
944.
I A Bochkov O D Trofimova O S Darbeeva R S Cherkasskaia M S Shevchuk 《Laboratornoe delo》1989,(6):43-47
Formulae for the calculation of the count of microorganisms isolated from natural bacterial biocenoses of a child's body have been derived. The authors suggest a variant of simplified drip method for the computation of microorganism colonies in solid media. The described method helps cut down the nutrient media consumption at least 3-fold and is time-saving. 相似文献
945.
B A Sommerville C G Scanes R Swaminathan A D Care S Harvey A Chadwick 《General and comparative endocrinology》1989,76(2):261-266
An experiment was carried out to investigate the effect of a range of estradiol (E2) doses (0.1-6.5 micrograms/g body wt/day) on vitamin D metabolism and the plasma levels of growth hormone (GH) and prolactin (PRL) in the growing chick. Doses of 0.5-0.7 microgram/g E2, which are insufficient to raise the plasma calcium level, did induce an increase in growth rate, an increase in 25-hydroxyvitamin D 1 alpha-hydroxylase (1-hydroxylase) and 24-hydroxylase activities, and an increase in plasma GH level. These parameters leveled off or fell over the dose range 1-2 micrograms/g E2 but there was evidence of a second peak in 1-hydroxylase activity at 6 micrograms/g E2. At this high dose rate, the plasma Ca level rose to 8 mM, as it does in the laying hen; 24-hydroxylase activity, growth rate, and plasma GH and plasma PRL levels all decreased. It was concluded that the dose response to estrogen in the growing chick is not linear and, in the case of 1-hydroxylase activity, may even be biphasic. 相似文献
946.
D Brewster 《Tropical doctor》1989,19(3):100-4 contd
With proper nursing care and procedures, small hospitals in rural areas of developing countries can provide good neonatal care and achieve perinatal mortality rates comparable to those found at teaching hospitals. The 1st ingredient of adequate neonatology is the establishment of proper regimens for feeding, observation, and resuscitation of newborns. Even in areas where the majority of births take place at home, good neonatal care is possible as long as local risk factors are identified, all newborns are screened for these factors, and at-risk infants are referred for treatment. Factors that place infants at risk include birthweight under 2 kg or above 4 kg, delivery before 34 weeks' gestation, respiratory distress, severe birth asphyxia or trauma, jaundice, prolonged rupture of the membranes, infant not sucking or febrile, convulsions, congenital malformations, and maternal disease. 4 areas require special knowledge on the part of health personnel: the asphyxiated infant, hypothermia, hypoglycemia, and neonatal sepsis. Health workers must be familiar with proper resuscitation techniques, especially avoidance of excessive suctioning of the pharynx, and be alert to signs of hypoxic ischemic encephalopathy. Premature, small, asphyxiated, and sick infants are at greatest risk of hypothermia, a condition that can be prevented by drying and wrapping newborns immediately. Providers should be alert to signs of hypoglycemia in infants of diabetic mothers, large-for-gestational-age babies, the low- birthweight infant, and sick babies. To prevent sudden infant deaths, all sick newborns should be treated for neonatal sepsis. 相似文献
947.
Tiziano Curti MD Gianandrea Pasquinelli MD Paola Preda BS Antonio Freyrie MD Renzo Laschi MD Massimo D’Addato MD 《Annals of vascular surgery》1989,3(4):351-363
Human adult endothelial cells were enzymatically harvested from adipose tissue. Cell viability was established by Trypan blue exclusion and transmission and scanning electron microscopy. Endothelial cells were identified by immunocytochemical investigation at light microscopy, transmission electron microscopy, and scanning electron microscopy. Isolated cells were positive for actin and vimentin, negative for desmin. Factor VIII RA was mainly expressed at cell surface and occasionally disclosed in the cytoplasm. Reactivity for UEA I and J15 was weak or undetectable. Human endothelial cells were seeded and left to adhere for one hour onto different nonvascular substrates (glass, poly-l-lysine, formvar-carbon, fibronectin, Teflon). Scanning electron microscopy defined surface features, suggesting tenacious cell adhesion on the substrate. Different vascular substrates were tested (preclotted Dacron, albumin Dacron, Hemashield Dacron, Gelseal Dacron, ePTFE, fibronectin-ePTFE). Commercially available coated grafts showed qualitative and quantitative differences in cell adhesion. In particular, Gelseal Dacron provided the best quantitative results, even though a wide variability was observed. In contrast, fibronectin-coated ePTFE gave more reliable results and high spreading efficiency. In the short term, coated grafts do not seem to offer greater advantages than fibronectin-coated ePTFE. However, specific incubation times for each coated graft should be selected and the long-term approach (graft culture) should also be attempted. 相似文献
948.
949.
950.
The administration of prophylactic antibiotics in surgery is appropriate for many patients. Data have shown extending the duration of prophylaxis beyond 48 hours does not lower the rate of postoperative-infection. The purpose of this project was to concurrently assess the duration of prophylactic antibiotic use. A total of 95 patients were monitored over 3 weeks. Eighty patients (84.2%) received antimicrobial therapy. In 23 of these patients (28.75%) the duration of antibiotic administration was longer than 2 days without clinical or microbiological evidence of infection. In 5 other patients only postoperative antibiotics were prescribed. The cost difference between the actual duration of antibiotic administration and 2 days of the same regimen was +1,364.58. Extrapolating for one year, it can be estimated that antibiotic costs could be reduced about +23,600. Pharmacists can focus on the duration of antibiotic prophylaxis as a cost containment measure. 相似文献