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171.
This article examines the attaching and detaching experience of a mother encountering the perinatal death of a twin. Her experience is related to the relevant theoretical and research literature pertaining to prebirth and postbirth maternal-infant attachment and detachment (grieving). Literature for both single infants and twins is considered. The experience of this mother suggests that elements of postbirth attachment may have been accelerated into the prebirth period. In addition, her postbirth attaching and detaching experience suggests that an attachment and detachment to the twins as a unit preceded detachment from the twin who died. The health care provider's role in promoting maternal well-being, and indirectly the well-being of the surviving infant, is described.  相似文献   
172.
Among the hemodynamic factors influencing intimal hyperplasia in the anastomotic region of a vascular graft, wall shear rate is believed to be one of the most important. We would like to study the effects radial wall motion on the wall shear rate distribution in the end-to-end anastomosis model of an artery and a divergent graft. Rigid and elastic models are constructed and the wall shear rate distributions are measured along the anastomosis using photochromic flow visualization method for carotid and femoral flow waveform. The mean and peak of shear rate decrease along the divergent graft, and the decreases are more significant in the elastic model. The shear rate waves are decomposed using the Fourier transform in order to separate the effects of radial wall motion and geometry. The percentage reductions of mean wall shear rates compared to steady shear rates at mean flow are calculated, and additional 8% (carotid) and 22% (femoral) reductions are observed in the elastic models near the end of the divergent graft. Also radial wall motion decreases the amplitudes of higher harmonics of wall shear rates in the elastic models. Since radial wall motion may affect the flow field differently for different geometry, wall elasticity should be considered in studying arterial hemodynamics.  相似文献   
173.
Although thoracoscopic sympathectomy or sympathicotomy is the best treatment for hyperhidrosis palmaris, a new approach of clipping only without transection of T2-sympathetic trunk is just as effective. Aside from the guaranteed cure of hyperhidrosis, this new method has fewer complications and has the advantage of recovery of the sympathetic tone in the hands if the procedure is reversed by the removal of the clips. Between March 18 and September 30 of 1996, 326 patients (190 female and 136 male with a mean age of 20.5 years) underwent thoracoscopic T2-sympathetic block by clipping to treat hyperhidrosis. Good results and few complications were noted during follow up six months to one year postoperatively. Five of the 326 patients, all female, had the operation reversed because of intolerable compensatory sweating. Three recovered from the compensatory sweating within two months and had less palmar sweating than before their sympathetic block; the fourth achieved relief of compensatory sweating after nine months, and the fifth reported no improvement.  相似文献   
174.
OBJECTIVE: Previous studies of surgical treatment for acromegaly have used varied criteria for 'cure', but elevated GH levels are considered to be associated with continuing disease activity. We wished to analyse the results of transsphenoidal pituitary surgery for acromegaly and assess the longer-term outcome for patients not offered further treatment when post-operative levels of GH < 5 mU/l were achieved. DESIGN: We studied a retrospective group of patients who underwent transsphenoidal surgery for acromegaly at St Bartholomew's Hospital between 1985 and 1993. PATIENTS: One hundred consecutive patients (53 male, mean age 46 years, range 18-68 years) undergoing transsphenoidal surgery for acromegaly were assessed. The patients were followed for a mean of 3.8 years (range 0.5-8 years) after operation. MEASUREMENTS: GH levels are represented as a mean value from a four-point day curve taken at 0830, 1300, 1700 and 1900 h. ACTH reserve was assessed basally and, if this was normal, with the insulin tolerance or glucagon tests. TSH, T4, PRL, LH, FSH, testosterone or oestradiol and plasma and urine osmolality were also measured. RESULTS: Post-operatively, 42% of patients achieved a mean GH level of < 5 mU/l. The success of surgery was related to the preoperative GH level; 65% of the patients with preoperative GH levels < 20 mU/l but only 18% of the patients with GH levels > 100 mU/l achieved post-operative GH values < 5 mU/l. In addition, tumour size influenced the outcome of surgery with 61% of patients with a microadenoma but only 23% of patients with a macroadenoma achieving post-operative GH levels of < 5 mU/l. Of the 42 patients considered in remission post-operatively (mean GH < 5 mU/l), 32 were available for long-term follow-up and were not offered any further treatment: only one of these has shown evidence of mild biochemical recurrence after a mean follow-up of 3.8 years (range 0.5-8). There were no peri-operative deaths. Two patients required surgical repair for CSF leaks and there were eight documented cases of meningitis. Permanent diabetes insipidus was noted in eight patients post-operatively. New anterior pituitary deficiency occurred in 21% of patients following surgery; 73% had unaltered pituitary function and in 6% recovery of partial hypopituitarism was noted. CONCLUSIONS: The stated outcome of surgery depends on the criteria adopted. Safe GH levels (mean levels < 5 mU/l) can be achieved in 42% of an unselected series of patients with acromegaly and if the tumour is a microadenoma this figure rises to 61%. Based on the current evidence it is safe not to offer further treatment to those patients in whom post-operative GH < 5 mU/l are achieved.  相似文献   
175.
This study is a retrospective review of admissions, discharge records and blood culture results of neonates admitted to the Neonatal Intensive Care Unit of Korle Bu Teaching Hospital in Accra, from the first of January 1991 to the 31st of December 1992. During this two year period there were 443 positive blood cultures. Ninety percent of the blood cultures were from babies born in Korle Bu Teaching Hospital, thus making the incidence of neonatal bacteraemia 22.2 per 1000 live births. The overall mortality rate was 37.2%. Gram negative bacteria accounted for 70.9% and Gram positive bacteria for 29.1% of all neonatal bacteraemia. The most common isolates were Enterobacter species 29.6%; Streptococcus faecalis 14.4%; Staphylococcus aureus 10.8%; Acinetobacter species 9.5%; Klebsiella species 9% and Escherichia coli 8.8%. It is concluded that the incidence of neonatal bacterial sepsis is high in our hospital and is associated with a very high mortality rate. There is thus an urgent need to institute appropriate preventive and therapeutic measures.  相似文献   
176.
Nonhyperfunctioning adrenal lesions such as cysts, myelolipomas, adrenal haemorrhage, adenoma and metastases are described. Definitive imaging features that help characterize adrenal cysts, myelolipomas and adrenal haemorrhage are illustrated and the differentiation of benign from malignant adrenal lesions using an algorithmic approach based on lipid sensitive imaging is provided.  相似文献   
177.
178.
We present the characteristic features of 14 children with the recessive form of Robinow syndrome and the growth hormone (GH) response to provocation with clonidine and the serum insulin-like growth factor-I (IGF-I) concentration in 12 of these children. The gonadotropin (luteinizing hormone [LH] and follicle-stimulating hormone [FSH]) response to gonadotropin-releasing hormone (GnRH) was evaluated in early pubertal and pubertal patients, and the testosterone response to human chorionic gonadotropin (HCG) was evaluated in males. Children with Robinow syndrome, born at full-term, were short at birth (length, 41.4+/-2.1 cm) and had markedly slow growth velocity (GV) during the first year (13.1+/-2.1 cm/yr); consequently, they were significantly short at the end of the first year of life (length, 54.4+/-2.9 cm). This intrauterine and early extrauterine growth delay reflected low growth potential. During childhood, the GV standard deviation score (GVSDS) remained low (-2.17+/-0.83). Despite the presence of empty sella in all of the patients, they had an adequate GH response to clonidine provocation (peak, 19.3+/-5.8 microg/L) and a normal serum IGF-I concentration (309+/-142 ng/mL) for their age. During childhood and early adolescence, boys with Robinow syndrome had low basal testosterone and a low testosterone response to HCG stimulation (3,000 IU/m2/d intramuscularly [IM] for 3 days). However, their basal and GnRH-stimulated FSH concentrations were normal. Two girls (Tanner II breast development) had a normal serum estradiol (E2) concentration but high LH and FSH responses to GnRH stimulation. This suggested either defective feedback of E2 on the hypothalamic-pituitary axis or hyporesponsiveness of the ovaries to gonadotropin. Four weeks of HCG therapy (2,500 IU/m2 IM twice weekly) in three boys with Robinow syndrome increased the penile length and testicular volume, denoting a significant Leydig cell response to prolonged HCG stimulation and the presence of functioning androgen receptors. It is suggested that HCG and/or testosterone therapy during infancy may improve the severe micropenis in these patients.  相似文献   
179.
The pool of thrombin and fibrinogen in circulation, in organs, and on cardiopulmonary bypass devices was quantified during and after cardiopulmonary bypass in four groups of 24 Yorkshire pigs (weight, 30-35 kg); two groups of 10 unoperated pigs were used as controls. Thrombin-alpha and fibrinogen were iodinated with 125iodide using an iodogen transfer technique; 250-300 microCi of these tracers were injected intravenously 1 hr before cardiopulmonary bypass. All pigs were systematically heparinized (activated clotting time > 400 sec); cardiopulmonary bypass was performed at 2.5-3.5 L/min at 28 degrees C using a centrifugal pump, oxygenator (Bentley Univox 1.8 m2; Bentley Inc., Irvine, CA), arterial filter (0.25 m2), and cardiotomy reservoir (BMR 3500) for 90 min, followed by a 90 min reperfusion and 180 min of cardiopulmonary bypass. Iodinated thrombin-alpha and fibrinogen in intact organs and samples of blood, organs, tissues, and oxygenator-arterial filter-cardiotomy reservoir were quantified with an ion chamber and a gamma counter, respectively. The percent of injected iodinated thrombin-alpha and fibrinogen dose (mean +/- SD) in organs and cardiopulmonary bypass devices of all groups of cardiopulmonary bypass pigs was calculated. Thrombin generated at the small area of surgical wounds (0.016-0.038 m2), and fibrin deposited on surfaces of cardiopulmonary bypass devices (2.59 m2), initiate and propagate thrombus formation and embolization. The protein level reached saturation values on all cardiopulmonary bypass devices at 180 min. High levels of thrombin and fibrinogen-fibrin circulate in blood and organs, and are adsorbed on cardiopulmonary bypass devices; this large blood pool of pro-coagulants in the cardiac cradle, tissues, and perfused organs may account for thrombi and emboli during and after cardiopulmonary bypass.  相似文献   
180.
In previous work, we showed a robust gamma-aminobutyric acid (GABAergic) synaptic input onto embryonic luteinizing hormone-releasing hormone (LHRH) neurons maintained in olfactory explants. In this study, we identify GABAergic neurons in olfactory pit (OP) of embryonic mice in vivo and study, using patch-pipet whole-cell current and voltage clamp techniques, synaptic interactions of these neurons in explant cultures. In vivo, glutamate decarboxylase (GAD, the enzyme which synthesizes GABA) mRNA was first detected in nasal regions on Embryonic Day (E) 11.5. From E12.5 to E13.5, robust GAD expression was localized to cells primarily in the ventral aspect of the OP. GAD mRNA was not detected over dorsally located cells in olfactory sensory or respiratory epithelium. In addition, GAD mRNA was not observed in cells along olfactory axons. GAD mRNA was dramatically reduced in the OP/vomeronasal organ by E16.5. Using antibodies against both GABA and GAD, immunopositive axonal-like tracts were detected in the nasal septum on E12.5. GABAergic staining decreased by E13.5. To examine synaptic interactions of these GABAergic cells, embryonic olfactory explants were generated and maintained in serum-free media. As explants spread, neuron-like cells migrated into the periphery, sometimes forming ganglion-like clusters. Cells were recorded, marked intracellularly with Lucifer Yellow and post-fixation, immunocytochemically examined. Forty-six cells, typically multipolar, were GABAergic, had resting potentials around -50 mV, and exhibited spontaneous action potentials which were generated by spontaneous depolarizing GABAergic (GABAA) synaptic activity. OP neurons depolarized in response to GABA by increasing Cl- conductance. The biophysical properties of OP-derived GABAergic neurons were distinct from those reported for olfactory receptor neurons but similar to embryonic LHRH neurons. However, unlike LHRH neurons, GABAergic neurons did not migrate large distances in olfactory explants or appear to leave the olfactory pit in vivo.  相似文献   
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