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71.
Red blood cells (RBCs) can be cryopreserved with shelf life of 10 years. However, shelf life of deglycerolized RBCs in conventional open system is just 24 hours, resulting in sporadic use of Frozen RBC (FS-RBC). Recently Naval Blood Research Laboratory (NBRL) method using ACP 215 (ACPTM 215 Haemonetics Cell Processing System) has been introduced, where shelf life of deglycerolized RBC is 14 days. FS-RBC unit is prepared from single blood donation, which needs to be glycerolized and deglycerolized. NBRL method using ACP 215 in FS-RBC is described. Deglycerolized unit weighed between 325–350 gm with haemoglobin of 15–18 gm/dl and freeze- thaw- wash RBC recovery of 87%. Transfusion of deglycerolized RBC offered advantages such as elimination of need of crossmatching in emergent situations and reduction of transfusion reactions. FS-RBC by NBRL method using ACP 215 has advantages such as long shelf life, meeting unexpected high blood demand in mass casualties situations or availability of rare blood group requirement of individual patient. FS-RBC can be a potential candidate for Indian Armed Forces Blood programme for uninterrupted blood supply during peace and war. 相似文献
72.
Objective:To provide information on twin births and associated factors in Port barcourt South South Nigeria.Methods:Data on twin deliveries from 1st January 2003 to 31st December 2008 were collected and analysed.This included the maternal age and parity,gestation age,Apqar scores,sex and birth weight of twins.Results:A total of 11042 deliveries occurred over the study period with 333 being twins giving a twin rate of 1∶33.Male twins constituted 48% of twin births with male to female ratio of 1∶1.08.The mean age and parity of mothers were 29.6 years and 2.5 respectively.Presentation of the cephalic/cephalic for the first and second twins was the most common(63.4%).Severe birth asphyxia(first minute Apgar score 1-3)occurred in 3.9% of twins.Male-male twin pair occurred in 28.5% of twins,male-female in 39% while female-female occurred in 32.5%.The Caesarian section rate was 48%.Conclusion:The twining rate in this study is high.In this locality,there is a need for early ultrasound scanning of pregnant women particularly those of parities 1 to 3 and those aged 25-34 years in whom highest rates of twinning occurred to detect twinning when present and refer them to sufficiently equipped centres for adequate antenatal and perinatal care. 相似文献
73.
Duncan RC Spalding Kasim A Behranwala Peter Straker Jeremy N Thompson Robin CN Williamson 《Annals of the Royal College of Surgeons of England》2009,91(6):477-482
INTRODUCTION
Non-occlusive small bowel necrosis (NOSBN) has been associated with early postoperative enteral feeding. The purpose of this study was to determine the incidence of this complication in an elective upper gastrointestinal (GI) surgical patient population and the influence of both patient selection and type of feeding jejunostomy (FJ) inserted, based on the experience of two surgical units in affiliated hospitals.PATIENTS AND METHODS
The records were reviewed of 524 consecutive patients who underwent elective upper GI operations with insertion of a FJ for benign or malignant disease between 1997 and 2006. One unit routinely inserted needle catheter jejunostomies (NCJ), whilst the other selectively inserted tube jejunostomies (TJ).RESULTS
Six cases of NOSBN were identified over 120 months in 524 patients (1.15%), with no difference in incidence between routine NCJ (n = 5; 1.16%) and selective TJ (n = 1; 1.06%). Median rate of feeding at time of diagnosis was 105 ml/h (range, 75–125 ml/h), and diagnosis was made at a median of 6 days (range, 4–18 days) postoperatively. All patients developed abdominal distension, hypotension and tachycardia in the 24 h before re-exploratory laparotomy. Five patients died and one patient survived.CONCLUSIONS
The understanding of the pathophysiology of NOSBN is still rudimentary; nevertheless, its 1% incidence in the present study does call into question its routine postoperative use especially in those at high risk with an open abdomen, planned repeat laparotomies or marked bowel oedema. Patients should be fully resuscitated before initiating any enteral feeding, and feeding should be interrupted if there is any evidence of feed intolerance. 相似文献74.
There is a great and unmet need for meaningful therapies that will deliver restorative solutions to patients with neurological disorders such as multiple sclerosis (MS), Parkinson's disease and stroke. The emergence of human embryonic stem cells as an experimental and therapeutic resource represents a major opportunity for brain repair. Embryonic stem cells offer the potential to study human cells, model disease, accelerate drug discovery and of themselves act as a cell-based therapy. In contrast to other organs, a "one size fits all" approach is inappropriate for repair of the brain; rather therapies need to be "bespoke". The design and development of embryonic stem-cell based CNS reparative strategies pose many challenges, both conceptual and practical. Using multiple sclerosis as an example, this paper addresses the needs for the translation of embryonic stem cell biology to regenerative neurology. 相似文献
75.
76.
CN Storrs 《Archives of disease in childhood》1977,52(7):534-540
Cardiovascular reflex responses have been studied in 9 newborn preterm infants with apnoeic episodes and in 2 preterm infants with periodic breathing. Respiration, blood pressure, heart rate, and peripheral blood flow were simultaneously recorded. Peripheral blood flow was measured in the leg by venous occlusion plethysmography. During apnoea, bradycardia and peripheral vasoconstriction occur. There is little change in blood pressure though pulse pressure increases. No cardiovascular changes were seen before the onset of apnoea. Periodic breathing had little effect on peripheral blood flow. Preterm infants with gestations as low as 27 weeks apparently have well developed chemoreceptor reflexes which would tend to preserve blood supply to the brain during conditions of hypoxia. 相似文献
77.
Comparative effects of ivabradine, a selective heart rate-lowering agent, and propranolol on systemic and cardiac haemodynamics at rest and during exercise
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Joannides R Moore N Iacob M Compagnon P Lerebours G Menard JF Thuillez C 《British journal of clinical pharmacology》2006,61(2):127-137
AIM: To compare in humans the effects of ivabradine and propranolol on cardiac and systemic haemodynamics at rest, during tilt and exercise. METHODS: Nine healthy volunteers randomly received single oral doses of ivabradine (Iva, 30 mg), propranolol (Propra, 40 mg) or placebo (Plac) during a double-blind cross-over study. Doses were selected to be equipotent in heart rate (HR) reduction. HR, systolic and diastolic blood pressure (SBP, DBP), cardiac index (CI, bioimpedance), rate pressure product (RPP), plasma epinephrine (E) and norepinephrine (NE), were measured at rest at baseline, before and after two tilt and exercise tests, started 2 and 5 h after drug intake. Heart rate variability (low to high frequency ratio LF/HF) was evaluated at rest and at 5 th minute of tilt. RESULTS: At rest, HR and RPP decreased similarly with Iva and Propra (both P < 0.01). During tilt, HR increased less with Iva than Propra (P < 0.01), LF/HF decreased after Iva (P < 0.03), SBP and mean blood pressure decreased after Propra (both P < 0.01), RPP decreased similarly after Iva and Propra (both P < 0.01) and CI decreased to a greater extent with Propra than with Iva or Plac (both P < 0.04). During exercise, Iva and Propra similarly decreased HR (both P < 0.01) and RPP (P < 0.01). CONCLUSIONS: These results demonstrate that for a similar decrease in HR at rest and during sympathetic stimulation, acute administration of ivabradine, a selective heart rate-lowering agent, decreased myocardial oxygen demand to the same extent as a reference beta-blocker, propranolol, but without evidence of depressant effect on cardiac function. 相似文献
78.
79.
S-carboxymethyl-L-cysteine (carbocysteine) improves the visco-elastic properties of bronchial mucus in vivo, possibly as a result of an increase in the relative proportions of sialomucins in bronchial mucus. Carbocysteine was therefore studied in vitro and ex vivo in both normal and bronchitic rats on pulmonary sialyl transferase, responsible for the addition of sialic acid to mucus glycoproteins. Bronchitis was induced in male Sprague-Dawley rats by repeated exposure to sulphur dioxide for two weeks. During this time they received either 500 mg kg-1 day-1 carbocysteine or its vehicle by the oral route. Rats not being exposed to SO2 received the same treatment. The animals were then killed, and subcellular fractions prepared by differential centrifugation of lung homogenates. Sialyl transferase was assayed using CMP-14C sialic acid as substrate and desialysed fetuin as exogenous acceptor. Enzyme activity was located in both the (Golgi-containing) 10,000 g and 100,000 g pellets with minor activity in the cytosolic supernatants. When tested in vitro between 10(-6) and 10(-3) M, carbocysteine had no effect on sialyl transferase activity in microsomes taken from healthy or bronchitis rats. Repeated administration of carbocysteine was without effect on the sialyl transferase activity in 10,000 g pellets taken from healthy rats. However, in bronchitic rats there was a small but statistically significant (P less than 0.05) increase in enzymic activity in the treated group compared to the animals receiving the vehicle. There was no difference in the activity of the microsomal enzyme compared to vehicle-treated controls in either healthy or bronchitic rats. We conclude that it is possible that an increase in sialyl transferase activity in a Golgi-containing fraction of bronchitic lungs could explain the relative increase in sialomucins in bronchitic subjects. 相似文献
80.