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61.
NORPLANT® progestogen-only implant contraception providesseveral years of effective protection against pregnancy followinga single application. It is reversible whenever desired, withreturn to normal fertility. Drug release and concentrationsare maximal in the first month of use, when a set of six capsulesreleases 85/µg/day of levonorgestrel. Release is 25–30/µg/dayat 60 months. Circulating drug concentrations and pregnancyrates vary inversely with body weight at placement, but evenamong heavier women, failure rates are below those of oral contraceptivesin the general population. Side-effects are most marked at theinitiation of use. Disruption of normal menstrual patterns occursin 70–80% of recipients initially. Menstrual blood lossis decreased, however, and most women experience modest increasesin haemoglobin. Headache, acne, other skin or hair problems,changes of weight and of mood and abdominal pain, are the mostcommon side-effects attributed to NORPLANT® contraception.The frequency of occurrence of side-effects diminishes withincreased duration of use. The comparative paucity of majorside-effects, coupled with the method‘s convenience andeffectiveness and its very long action have made NORPLANT®implants highly acceptable in both developing and developedcountries.  相似文献   
62.
In order to determine the prevalence of psychoactive substance use in three specialty groupings, 1,624 questionnaires were sent to physicians in medicine, surgery and anaesthesia; all had trained at the same academic institution. A response rate of 57.8% was achieved. Comparison of prevalence of impairment rates showed no differences between Surgery (14.4%), Medicine (19.9%) and Anaesthesia (16.8%). Substance abuse was clearly associated with a family history of abuse; 32.1% of the abusers had a family history of such abuse compared with 11.7% of the non-abusers. Increased stress at various career stages did not appear to increase substance abuse; problem areas during medical life times were similar for each specialty. Substances most frequently used were marijuana (54.7%), amphetamines (32.9%); and benzodiazepines (25.1%). Seventy-three used psychoactive drugs which were non-prescribed. Drug counselling programmes were judged inadequate by most. Use of alcohol and drugs by faculty members was reported by a number of respondents.  相似文献   
63.
Weight, midarm circumference, triceps skinfold thickness, arm muscle circumference, albumin, prealbumin, transferrin and total lymphocyte count were measured at each outpatient visit in patients reveiving home parenteral nutrition from September 1987 to November 1991. Each nutritional variable was analysed for individuals and for the whole group. Group data were expressed using the actual values obtained and successive differences (the change between clinic attendances). Nutritional variables were evaluated using a correlation matrix. Identical analysis of individual and group data demonstrates that laboratory investigations are of little value in the assessment of nutritional status in patients receiving home parenteral nutrition. Anthropometry detected changes in body weight secondary to changes in muscle and/or fat in 80% of patients. Pooling anthropometric data distors the relationship between variables owing to inter-individual variability when actual values are used. The method of successive differences is the preferred method of analysis for group anthropometric data.  相似文献   
64.
The modification of surface properties of biodegradable poly(lactide-co-glycolide) (PLGA) and model polystyrene nanospheres by poly(lactide)-poly(ethlene glycol) (PLA:PEG) copolymers has been assessed using a range of in vitro characterization methods followed by in vivo studies of the nanospheres biodistribution after intravenous injection into rats. Coating polymers with PLA:PEG ratio of 2:5 and 3:4 (PEG chains of 5000 and 2000 Da, respectively) were studied. The results reveal the formation of a PLA: PEG coating layer on the particle surface resulting in an increase in the surface hydrophilicity and decrease in the surface charge of the nanospheres. The effects of addition of electrolyte and changes in pH on stability of the nanosphere dispersions confirm that uncoated particles are electrostatically stabilized, while in the presence of the copolymers, steric repulsions are responsible for the stability. The PLA:PEG coating also prevented albumin adsorption onto the colloid surface. The evidence that this effect was observed for the PLA:PEG 3:4 coated nanospheres may indicate that a poly(ethylene glycol) chain of 2000 Da can provide an effective repulsive barrier to albumin adsorption. The in vivo results reveal that coating of PLGA nanospheres with PLA:PEG copolymers can alter the biodistribution in comparison to uncoated PLGA nanospheres. Coating of the model polystyrene nanospheres with PLA:PEG copolymers resulted in an initial high circulation level, but after 3 hours the organ deposition data showed values similar to uncoated polystyrene spheres. The difference in the biological behaviour of coated PLGA and polystyrene nanospheres may suggest a different stability of the adsorbed layers on these two systems. A similar biodistribution pattern of PLA:PEG 3:4 to PEG 2:5 coated particles may indicate that poly(ethylene glycol) chains in the range of 2000 to 5000 can produce a comparable effect on in vivo behaviour.  相似文献   
65.
Communication is becoming increasingly identified as a significant factor influencing the ability of the NHS to achieve high-quality outcomes. Typically, organizations have tended to conceptualize communication as a process dealing with external relationships. Emphasizes the importance of both internal and external communications, and argues that the NHS now needs to integrate both these dimensions of the communication function. Proposes a strategic framework which suggests how this can be accomplished. Proposes and discusses a communications-centred model of the management process in the light of this approach. This model integrates perspectives which have hitherto dichotomized management as either a science or an art. It also locates communication at the heart of effective management. Finally, suggests the NHS is uniquely well placed to provide data on the impact and costs of total communication programmes.  相似文献   
66.
67.
Two phase I vaccine trials were conducted to test the immunogenicity and safety of a vaccine containing three recombinant malaria antigens from the asexual stage of Plasmodium falciparum. The three antigens are a fragment of MSP1 (190LCS.T3); MSP2 and a portion of RESA and were formulated in Montanide ISA720 adjuvant. These trials investigated the dose response of each antigen for eliciting both antibody and T-cell responses and the immunogenicity of a mixture of the antigens compared with the antigens injected separately. All three antigens elicited both antibody and T-cell responses. Strong T-cell responses were observed with 190LCS.T3 and RESA with stimulation indices exceeding 100 for peripheral blood leucocytes in some individuals. The antibody responses were generally weak. The human antibody responses observed with MSP2 in Montanide ISA720 were not significantly different from those obtained in an earlier trial which used MSP2 with alum as the adjuvant. No antigenic competition was observed: volunteers receiving a mixture of antigens had similar responses to those receiving the three antigens at separate sites. Tenderness and pain at the injection site were common over the first few days following immunization. In some volunteers, especially those receiving the highest doses tested, there was a delayed reaction at the injection site with pain and swelling occurring approximately 10 days after injection.  相似文献   
68.
Thirty-six renal allograft recipients were monitored by serial duplex Doppler ultrasound studies post-transplant and during early rejection. A separate reproducibility study demonstrated no significant inter- or intra-operator variability in measurements of resistive index of an interlobar artery (RI) (2.1% [1.5%] and 3.2% [2.3%] respectively, mean [standard error] of coefficients of variance). Twenty-one patients had rejection within 3 weeks of transplantation. These grafts showed greater overall rises in the RI, from day 2 to day 5 post-transplant, than the grafts which had no rejection. Eleven of the 21 patients required more than one course of methyl-prednisolone for persistent or recurring rejection. These grafts had higher RI on the day rejection was diagnosed (81 [7.3], median [interquartile range]) compared with the remaining 10 patients (68.6 [8.7]). The 11 grafts with persistent rejection had higher RI (p less than 0.005, Mann-Whitney U-test) on day 2 post-transplant (76 [3.9]) compared with the 10 grafts successfully treated with a single course of methyl-prednisolone (63.2 [10.9]). This study demonstrates that grafts with an RI of greater than 70 on day 2 post-transplant are likely to have rejection requiring additional treatment (sensitivity--100%, specificity--80%). These patients may be candidates for earlier or alternative anti-rejection therapy.  相似文献   
69.
Anterograde and retrograde transport techniques were used to study the connexions between different subdivisions of the auditory cortex and thalamus with the thalamic reticular nucleus in the prosimian, Galago. In particular, the goal was to determine whether the primary auditory nucleus, GMv, and its cortical target, area I of the auditory cortex (A I), project to a different region of the auditory sector of the reticular nucleus from the secondary auditory nuclei, GMmc and Po and their cortical targets outside A I. The results show that the projections to and from the auditory sector are indeed segregated: injections of wheatgerm agglutinin-conjugated horseradish peroxidase into either GMmc or Po labelled cells and terminals along the medial, lateral and ventral borders of the auditory sector, forming a U-shaped pattern. Projections from area II of the auditory cortex produced almost an identical pattern of the terminal labelling in the auditory sector. In contrast, injections into GMv-labelled cells and terminals in the centre region of the auditory sector, in the 'interior' of the U-shaped region. Projections from A I were distributed to both the U-shaped border region and the central core of the auditory sector probably because A I received projections from GMmc, Po and GMv. The significance of these results depends on a comparison between the auditory and visual sectors of the reticular nucleus. Both sectors are divided into tiers or subsectors-one related to the primary relay nucleus, i.e. GLd or GMv, and the other related to the secondary relay nuclei, i.e. pulvinar nucleus, GMmc, Po, etc.  相似文献   
70.
During treatment the schizophrenic child begins to emerge from his constricted, self-centered world and to enjoy interaction, play and playfulness. Many of the parents are as constricted and unable to play as their children. The use of a play corner, dress-up clothes and a staff member who can model roles to play helps reduce the work of play for parents and child. Their resulting mutual pleasure and increased spontaneity enhances treatment.professor of psychiatry and Director of the Division of Child and Adolescent Psychiatry and Children's Psychiatric Center  相似文献   
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