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101.
The hemostatic dysfunction induced by cardiopulmonary bypass is due, in part, to a platelet dysfunction evidenced by a postoperative extension of the bleeding time; it leads to increased postoperative blood loss and morbidity. This study, which was conducted in 85 patients undergoing cardiopulmonary bypass, was designed to characterize the hematologic changes during and after cardiopulmonary bypass and to elucidate the relationships between these changes, the extension of the bleeding time, and the magnitude of the postoperative nonsurgical blood loss. Variables were measured before, during, and 2, 24, 48, and 72 hours after cardiopulmonary bypass. Univariate and multivariate analyses were performed with either the 2-hour postbypass bleeding time or the 4-hour postbypass blood loss as the dependent variables. The reversal of the extension of the bleeding time in the postoperative period was accompanied by a significant increase in the mean platelet volume and by a significant increase in the level of thromboxane B2 measured in the blood shed from the site of the bleeding time determination. The postoperative bleeding time correlated with the postoperative blood loss, and both parameters were dependent on the duration of cardiopulmonary bypass. In addition, the postoperative bleeding time correlated with the skin temperature and the plasma level of D-dimer, while the postoperative blood loss also correlated with temperature and the plasma levels of C3. These data establish a direct relationship between the postoperative bleeding time, the postoperative blood loss, and temperature. They indicate that the reversal of the postoperative extension of the bleeding time is due in part to rewarming and to the release of larger platelets into the circulation, and they suggest that hyperfibrinolysis and complement activation may play an important role in the cardiopulmonary bypass-induced platelet dysfunction.  相似文献   
102.
The inconspicuous number of cases of self-induced hyperinsulinaemia reported in the literature may suggest that many are obscure enough to escape their detection. A case of fatal suicidal hyperinsulinaemia in a non-diabetic is reported here, and in whom only a retrospective biochemical analysis provided an explanatory cause of death. A quantitative radioimmuno assay (RIA) estimation of the refrigerated postmortem blood sample stored at 4 degrees C for three weeks gave a positive insulin yield. It reiterates the need, in forensic cases, for a very low threshold of suspicion and a good back-up for the appropriate body fluid analysis or tissue microexamination, especially when full details of the circumstances surrounding the death are not available at the autopsy. A brief résumé on insulin is presented as a background to the current forensic interest in the apparent increase in sudden deaths in young diabetics amidst the controversy about the bio-designed 'human' insulin and subjective unawareness of severe hypoglycaemia.  相似文献   
103.
Advances in biomedical science have resulted in dramatic improvementsin the medical care of chronically ill and handicapped children.Past measurement problems have resulted in a lack of clarityregarding the psychological adjustment of these children. Themothers of 270 chronically ill and handicapped children wereadministered the Child Behavior Checklist in an attempt to identifypatterns of behavioral functioning across six pediatric chronicdisorders: juvenile diabetes, spina bifida, hemophilia, chronicobesity, juvenile rheumatoid arthritis, and cerebral palsy.In general, it was found that children in all chronic disordergroups were perceived by their mothers as evidencing on theaverage more behavioral and social competence problems thanexpected based on norms for children in general. However, theirbehavioral and social adjustment was reported as better thanthat of a normative sample of children referred to mental healthclinics. There were essentially no differences between childrenwith different chronic disorders in terms of behavior problemsand social competence. The results were taken to support theview that these children were as a group at risk for adjustmentproblems. They were also discussed in terms of the noncategorialapproach, which suggests that similar psychosocial challengesare faced across pediatric chronic physical disorders.  相似文献   
104.
A case of Fournier's gangrene of the scrotum is reported in a 31-year old man who had outpatient vasectomy during an intercurrent diarrheal illness. The surgery was done through a midline incision, under local anesthesia of plain 2% lignocaine, with a preoperative chlorhexidine scrub. Although his scrotum was red and swollen within 3 hours, he did not have medical care until admission to hospital 48 hours later. At admission he had Fournier's gangrene of the scrotum and penis, Gram-negative septic shock, and acute renal failure. In the intensive care unit he was treated with continuous dialysis, parenteral metronidazole, benzylpenicillin, Ceftazidime and inotropes. He had a cardiorespiratory arrest after emergency radical debridement. After resuscitation he developed adult respiratory distress syndrome and disseminated intravascular coagulation. Pathological exam showed necrosis of the dermis and subcutaneous layers, thrombosis and beta-hemolytic streptococci. After adding gentamicin and vancomycin, 2 weeks of ventilator care, 4 more surgical debridements, a left orchidectomy, and a despite a grossly abnormal EEG recording, the man regained consciousness and recovered. His scrotal and penile skin re-epithelialized over 3 months. Patients requesting vasectomy should be assessed for local and systemic illness before performing the procedure.  相似文献   
105.
Trigger fingers and thumb: when to splint, inject, or operate.   总被引:5,自引:0,他引:5  
Fifty trigger fingers were treated by splinting of the metacarpophalangeal joint at 10 to 15 degrees of flexion for an average of 6 weeks (range, 3 to 9 weeks). Another 50 trigger fingers were injected with 0.5 ml of betamethasone sodium phosphate and acetate suspension (Celestone) and 0.5 ml of lidocaine. All patients were followed up for a minimum of 1 year (range, 1 to 4 years). Treatment was successful in 33 (66%) of the splinted digits and 42 (84%) of the injected digits. Fifty percent of the 10 splinted thumbs and 70% of the 40 splinted fingers had a successful outcome. Of the 17 unsuccessfully treated digits in the splinted group, 15 were later cured with injections and 2 required surgery. All of the 7 unsuccessfully treated digits in the injected group were cured with surgery. Patients with marked triggering, symptoms of more than 6 months' duration, and multiple involved digits had a higher rate of failure in both groups. Splinting offers an alternative for patients who have a strong objection to cortisone injection.  相似文献   
106.
Endothelin-1 (ET-1) levels are elevated in human breast tumours compared with normal and benign tissues, and in the presence of insulin-like growth factor 1 (IGF-I) ET-1 is a potent mitogen for human breast fibroblasts. In this study we have examined the ability of intact human breast cancer cell lines to process exogenously added big ET-1 (1-38) to the active mature ET-1 peptide by using a specific radioimmunometric assay. In both hormome-dependent (MCF-7, T47-D) and hormone-independent (MDA-MB-231) breast cancer cell lines the putative endothelin-converting enzyme (ECE) exhibited apparent Michaelis-Menten kinetics when converting added big ET-1 to ET-1. Both basal ET-1 production and exogenously added big ET-1 to ET-1 conversion were greatly reduced in all three cell lines in response to the metalloproteinase inhibitor phosphoramidon but were insensitive to other classes of protease inhibitors. Inhibition was also observed when cells were incubated in the presence of the divalent cation chelators 1,10-phenanthroline and EDTA. In MCF-7 cells the optimal pH for the ECE activity using a saponin cell permeabilisation procedure was found to residue within a narrow range of 6.2-7.26. Our results indicate that human breast cancer cells contain a neutral phosphoramidon-sensitive metalloproteinase which can process big ET-1 to ET-1. In the breast this conversion could contribute substantially to the local extracellular levels of this proposed paracrine breast fibroblast mitogen.  相似文献   
107.
Prolactin (PRL) has been shown to contribute to the development of lymphoid tissues and maintenance of physiological immune function. Here we show that the role of the hormone extends to the control of the effector phase of the immune response. In addition to triggering resting lymphocytes to cell division, the hormone can also control the magnitude of their response to polyclonal stimuli. Concentrations of PRL in the physiological range increased the [3H]thymidine, [3H]uridine, and [3H]leucine incorporation of unstimulated NK cells cultured in serum-free conditions. The same concentrations of the hormone increased the response of NK, T, and B cells to the mitogenic stimuli interleukin 2 (IL2), phytohemagglutinin (PHA), and staphylococcus aureus cowan, respectively, the effect being maximally evident in the presence of suboptimal concentrations of the mitogens. By contrast concentrations of PRL five- to tenfold the physiological levels inhibited the mitogenic response to IL2 and PHA. These data indicate a double-faceted regulatory role of this hormone in vivo.  相似文献   
108.
奎硫平和利培酮治疗精神分裂症的比较研究   总被引:11,自引:0,他引:11  
目的 以利培酮为对照 ,探讨奎硫平治疗精神分裂症的疗效和副作用。方法 将 79例符合CCMD 3诊断标准的精神分裂症病人随机分为两组 ,分别给予奎硫平和利培酮治疗 8周。采用阳性症状和阴性症状量表 (PANSS)评定临床疗效 ,副反应量表 (TESS)评定副反应。结果 治疗 8周后的疗效近似 (P >0 0 5 ) ;奎硫平组和利培酮组的显效率差异无显著性 (P >0 0 5 ) ;奎硫平组的副反应发生率低于利培酮组 ,但差异无显著性 (P >0 0 5 )。利培酮组锥体外系副反应和内分泌改变的发生均明显高于奎硫平组 (P <0 0 5 )。结论 奎硫平和利培酮对精神分裂症的疗效相当 ,副作用较小。  相似文献   
109.
PURPOSE: Efficacy and safety data regarding the unlabeled uses of botulinum toxins are reviewed, and the pharmacology, adverse effects, and characteristics of commercially available botulinum toxins are discussed. SUMMARY: More than 300 articles have been published on the use of botulinum toxins, particularly botulinum toxin type A, to treat conditions characterized by excessive smooth or skeletal muscle spasticity. Botulinum toxins are synthesized by Clostridium botulinum and cause temporary local paralysis of the injected muscle by inhibiting acetylcholine release at the neuromuscular junction. While botulinum toxins have Food and Drug Administration-approved labeling to treat a limited number of spasticity disorders, including cervical dystonia and blepharospasm, the toxins have more than 50 reported therapeutic uses. Among these uses, the most rigorously studied indications include achalasia, essential tremors, palmar hyperhidrosis, chronic anal fissures, headache prophylaxis, and limb spasticity. The main adverse effects of the toxins are pain and erythema at the injection site, although unintended paralysis of muscles adjacent to the site of toxin injection may also occur. CONCLUSION: Clinical studies support the use of botulinum toxins for certain conditions, although more studies are needed to establish the role of the drug relative to conventional therapies and to determine patient predictors of response. Although botulinum toxins are generally well tolerated, a patient-specific risk-benefit assessment should precede any decision to use them for unlabeled indications.  相似文献   
110.
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