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OBJECTIVES: To evaluate the postoperative analgesic efficacy, side effects and acceptance by patients and nurses of intravenous "patient-controlled analgesia" (PCA) with morphine, metamizole and buprenorphine. MATERIAL AND METHODS: In this randomized double blind prospective study of 150 patients in three groups receiving morphine (group A), metamizole (group B) or buprenorphine (group C), the patients had undergone low abdominal surgery with the same anesthetic protocol. Pain was recorded during the first 48 h after surgery on an orally-communicated scale of none or slight = 0, moderate = 1 and severe = 2. Upon the first report of moderate pain, patients were administered an intravenous bolus containing 5 mg morphine, 1 g metamizole or 0.15 mg buprenorphine. A perfusion pump was then connected and set with one bolus of 1.2 mg morphine, one of 333 mg metamizole or one of 0.04 buprenorphine. The maximum dose allowed in 24 h was 40 mg morphine, 8 g metamizole or 1.2 mg buprenorphine. The minimum interval between doses was 30 min for all three groups. Side effects reported were respiratory depression, sedation, nausea, vomiting, pruritus, perspiration and pain upon administration. Patients and nurses were asked to evaluate the system when the pump was disconnected and the results were then analyzed statistically. RESULTS: The analgesic effect was satisfactory in all three groups, with no significant differences among them. The percentages of patients reaching the maximum allowed dose on the first day were 2% with morphine, 18% (p < 0.05) with metamizole and 8% with buprenorphine. No respiratory depression was observed. Sedation was greater with morphine and buprenorphine than with metamizole (p = 0.0001). Pruritus was also greater with morphine and buprenorphine than with metamizole (p = 0.02) and pain upon infusion was greater with metamizole (p = 0.0002). CONCLUSIONS: Intravenous postoperative PCA was effective with all three drugs studied. Patient and nurse acceptance was good and side effects were few in the three groups. The lower rate of side effects for metamizole makes it the drug of choice.  相似文献   
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In a pot culture experiment, the effect of gypsum (50% of soil requirement), pyrites (equivalent to gypsum), farmyard manure (0.5 g per 100g soil) and Zn (10mg Zn kg–1 soil) on Zn equilibria in Ghabdan and Langrian series of sodic soils was studied. The equilibrium soil solutions collected anaerobically after 1, 14, 28, 42, 56, 70 and 84 days of submergence were analysed for pH, EC, HCO3 and Zn. Submergence markedly decreased soil solution pH and Zn up to 14 days and thereafter, the former slightly increased and the latter continued to decrease. Addition of amendments decreased soil solution pH in the order gypsum, pyrites and farmyard manure (FYM) and increased Zn concentration in the order FYM, gypsum and pyrites. The values of Zn potential (pZn + 2pOH) were within the range of pKsp for Zn(OH)2-Zn2+ (aq) from 16 to 84 days of submergence in Ghabdan soil and from 9 to 42 days of submergence in Langrian soil, where later it shifted to ZnCO3-Zn2+ (aq) system. Addition of FYM, pyrites and gypsum shortened the period of predominant existence of Zn(OH)2-Zn2+ (aq) system to 40, 30 and 12 days in Ghabdan soil and 30, 20 and 6 days in Langrian soil respectively. After these periods the system was saturated with respect to ZnCO3-Zn2+ (aq) except gypsum treatment where Zn-soil (unknown solid phases) -Zn2+ (aq) system controlled the solubility of Zn after 38 and 28 days of submergence of Ghabdan and Langrian soil respectively.  相似文献   
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Although some studies suggest positive effects of treatment for sexual offenders, most studies have been hampered by the unknown influence of selective attrition (e.g., volunteers and drop-outs). In the 1980s, the Correctional Service of Canada began to require weekly community treatment sessions for all sex offenders released in the Pacific Region. This policy change provided a unique opportunity for comparing an unselected cohort of treated sex offenders (n = 403) to an untreated cohort (n = 321) released in earlier years. After an average 12-year follow-up period, no differences were observed in the rates of sexual (21.1% vs 21.8%), violent (42.9% vs. 44.5%) or general (any) recidivism (56.6% vs 60.4%) for treated and untreated groups, respectively. The outcome remained comparable after controlling for length of follow- up, year of release, age, and seven static risk factors coded from official criminal history records. Retrospective ratings of the treatment quality also showed no relationship to observed recidivism rates. The static risk factors coded in the current study accounted for considerable variance in recidivism and could easily be used to improve statistical controls in future evaluations. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Pituitary tumors are mostly benign lesions, although 5-35% are locally invasive. A small number exhibit a more aggressive course, infiltrating dura, bone and sinuses, and are designated highly aggressive. However, the presence of metastases separate from the pituitary in the central nervous system or at a distance is necessary to designate pituitary tumors as carcinomas, i.e. truly malignant. When conventional therapeutic modalities fail, systemic chemotherapy remains the last option. We report seven such patients, three with highly aggressive and four with malignant pituitary tumors (n=4) four women; median age, 32 yr; range, 23-48 yr), who received one or more courses of chemotherapy with lomustine and 5-fluorouracil (median, two courses; range, one to six courses). Three patients with systemic metastatic disease had a shorter survival (median, 5 months; range, 1-14 months) than the one patient with central nervous system metastases alone (10 yr). A patient with an aggressive nonmetastatic prolactinoma who initially responded to chemotherapy died from another nondisease-associated cause. Two patients, one with an aggressive and one with a metastatic tumor, achieved symptomatic improvement with a median duration of 6 months. A hormonal reduction greater than 50% was observed in two of seven patients; only one patient who had an aggressive tumor obtained an objective tumor response. The median survival from the time of initiation of chemotherapy in patients with malignant tumors ranged from 3-65 months. Two patients with malignant tumors developed disease progression while receiving chemotherapy; no patient with extracranial metastases showed a response. Treatment was well tolerated, with minimal individual side-effects. Three patients with no response to initial treatment received different chemotherapeutic regimens with no additional response. All patients with metastatic malignant tumors eventually died. Treatment with cytotoxic chemotherapy is noncurative, and current experience is limited. Until another more specific form of treatment is available, chemotherapy may still be of some value in patients with highly aggressive and malignant pituitary tumors, at least in achieving a temporary remission or delay in progression. The combination of lomustine/5-fluorouracil proved easy to administer with minimal toxicity, although the response rate was only 14%. Until a more specific treatment is found, an optimal chemotherapeutic regimen needs to be established.  相似文献   
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Nicotinic acetylcholine receptors (nAChR) of the TE671 cell line were investigated using whole-cell and membrane patch recording techniques. At negative holding potentials (VH), pulses of acetylcholine (ACh) elicited whole-cell inward currents that rapidly desensitized. The EC50 value for ACh at VH = -60 mV was 7.8 microM. The ACh-induced current reversed at approximately 0 mV. Desensitization of nAChR by ACh was biphasic and reversible within approximately 20 sec. Spermine (1-100 microM) potentiated responses to ACh (10 microM - 1 mM) by reducing the rate of onset of desensitization; potentiation was inhibited by arcaine (10-100 microM). Spermine (1 mM) noncompetitively antagonized the AChinduced current. Antagonism by 1 to 5 mM spermine was voltage-dependent, increasing with negative VH. In 100 microM arcaine, this antagonism was shown to contain a voltage-independent component. Spermine (10 mM) increased the EC50 values for ACh, suggesting that at this concentration the polyamine is also a competitive antagonist. Single channel openings elicited during application of ACh to outside-out patches had a conductance of 47 pS at VH = -60 mV. At 10 and 100 microM, spermine increased channel open probability (po), but at 1 mM spermine, po was not significantly different from controls. The single channel conductance for ACh was unaffected by 10 and 100 microM spermine, but was decreased by 1 mM spermine. Spermine promoted the occurrence of approximately 27 pS openings. It is proposed that spermine acts at an excitatory modulatory site similar to that present on N-methyl-D-aspartate receptors and at least three inhibitory sites on nAChR of TE671 cells.  相似文献   
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Parents play a crucial role in the life of a child suffering from an anorectal malformation (ARM), since their guidance contributes to the degree to which the child learns to cope with his or her disability. We investigated whether they experience stress in parenting such a child and also attempted to identify somatic or behavioral characteristics in the child that influence the stress of parenting. The parents of 109 children (69 males, 40 females; median age 5.9 years, range 1-18 years) with an ARM (58 low, 10 intermediate, 41 high) were studied. The Nijmegen Questionnaire on Child-rearing Situations (NQCS) was used to investigate the existing parenting situation. Behavioral characteristics of the children were studied by means of the Child Behaviour Checklist (CBCL) and the Teacher Report Form (TRF). In a semi-structured interview, we investigated how parents experienced the implications of the disability in everyday life with their child. Our study showed that as far as the perception of parenting stress is concerned, parents of children with an ARM do not differ from those with healthy primary-school children. Within the group of parents with ARM-afflicted children, the parents of older, incontinent children experienced relatively more stress, especially when the child concerned was male. With regard to the children's behavior, the parents and teachers under investigation did not report a higher than normal incidence of deviant behavior. However, when individual parents observed difficult behavior in their child, they found it harder to deal with than the incontinence for feces. Regarding the implications of the disorder for their everyday lives, parents were concerned and indicated a need for specific counselling. We conclude that having a child with a somatic affliction, in this case an ARM, does not automatically imply that the parents experience child-rearing problems. However, certain groups of parents are more at risk, i.e., parents with older, incontinent sons and parents with children exhibiting behavioral problems. In addition, our study shows that parents do have difficulties in coping with the implications of the disorder and express a need for support. We feel that patient care can be improved if aid is tailored to these specific problems.  相似文献   
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