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21.
Determining mechanisms that can increase ethanol consumption during a single drinking bout is central to understanding alcohol abuse. When rodents are used as models to study excessive drinking, most often limited and transient increases in bout size are found with various manipulations. In a variety of studies, investigators have reported that schedule-induced drinking can result in excessive consumption of either water or alcohol (ethanol) during a single drinking period in food-restricted rats. The question examined in this experiment was, Could a schedule-induction paradigm increase bout size in nondeprived rats already self-administering ethanol? After the rats were trained to self-administer a 10% (volume/volume) ethanol solution in a fixed daily drinking session, non-response-contingent presentation of a 10% (weight/volume) sucrose solution, on a fixed-time, 120-s schedule, was used to determine whether additional ethanol consumption could be induced. This was followed by the use of a fixed-time, 300-s schedule and then, by using the fixed-time, 120-s schedule, with the presentation of a 2% (weight/volume) sucrose solution. None of these conditions induced an increase in ethanol self-administration. The results indicate that factors that control ethanol bout size in the nondeprived rat are such that the standard schedule-induction condition seems to be ineffective if an ethanol bout has occurred in the recent past.  相似文献   
22.
23.
G A Tolliver  H H Samson 《Alcohol》1989,6(5):381-387
Rats (N = 8) were housed (23 hr/day) in a test chamber in which the presentation of food pellets and 10% ethanol were a function of a concurrent fixed-ratio schedule of reinforcement. Water was available from a drinking tube. Following a 90-day period with food pellets presented on a fixed-ratio one schedule (FR 1) and ethanol on a FR 4, the FR schedule for food presentation was systematically increased. Daily food intake declined as the FR increased up to FR 64. Decreases in food were accompanied by reduced water consumption and a three-fold increase in ethanol intake. The major increase in ethanol intake was accounted for by an increase in the number of ethanol bouts/day rather than an increase in bout size. The 24-hr cyclic pattern of food, water and ethanol ingestive behaviors found in the 90-day FR 1 period was maintained as the food presentation schedule increased. Food, ethanol, and water intake returned to the pre-FR-manipulation levels with the introduction of the food FR 1 condition. The results were discussed in terms of caloric, fluid, and activity changes resultant from the effects of the FR manipulation. No single factor could account for the increased ethanol consumption. These effects were related to previous work which demonstrates increased ethanol intake when response parameters of concurrent reinforcements are changed.  相似文献   
24.
Thrombosis of the cerebral dural venous sinuses, cortical draining veins, and deep cerebral veins is a rare clinical finding. Because of its low incidence and multiple etiologies, the optimum therapy for this condition will only be elucidated by a multicenter, randomized prospective study. At our institution, we favor early and aggressive management of cerebral venous sinus thrombosis with transfemoral, venous intradural infusions of the fibrinolytic agent urokinase. To date, treatment of only 13 patients using this technique has been reported in the English literature. This report adds 12 more such treated patients. Despite the presence of preinfusion infarcts in 5 patients, four of which were hemorrhagic, we incurred no major therapeutic morbidity. Functional sinus patency was achieved in 11 of 12 patients, with our only true failure occurring in an individual with symptoms of at least 2 months' duration. Good to excellent clinical outcome was achieved in 10 of 11 patients (one newborn had inadequate follow-up).  相似文献   
25.
26.
 Cytogenetic analysis of a juxta-articular myxoma revealed two distinct cytogenetically abnormal cell populations: inv(2)(p15q36) and +7, t(8;22)(q11–12; q12–13). These clonal chromosomal changes, the first to be reported in this tumour type, suggest that at least some juxta-articular myxomas are neoplastic rather than reactive in nature. Received: 8 June 1998 / Accepted: 17 August 1998  相似文献   
27.
AIMS--To identify the histological changes in leprosy skin lesions over the first few weeks after the start of leprosy treatment and to examine their relationship to reversal reaction. METHODS--Sequential skin biopsy during treatment with multiple drug therapy. In this study, a series of 28 patients was studied, from whom two or more biopsies were taken at two week intervals. Fourteen patients had paucibacillary leprosy (PBL) and 14 had multibacillary leprosy (MBL). RESULTS--In most cases, granuloma fraction and bacterial index fell during treatment, the bacterial index being less sensitive than the granuloma fraction. Since the biopsies were fixed in buffered formalin and processed through to paraffin wax, little immunohistochemistry was feasible. However, there was strong evidence of immune activation, with increased expression of HLA-DR in the granulomas of MBL and PBL cases: the epidermis also expressed HLA-DR in several patients. Such changes may reflect gamma IFN production from granuloma lymphocytes. Patients with reversal reaction often showed HLA-DR expression on admission which decreased with corticosteroid treatment. CONCLUSIONS--The results suggest that activation of cell mediated immunity in leprosy lesions occurs during treatment with multiple drug therapy and may not be restricted to those with clinical evidence of reversal reaction.  相似文献   
28.
The HIV/AIDS epidemic is likely to remain the pre-eminent global health concern for the foreseeable future. In Uganda, while significant progress has been made by the government over the past decade in bringing down the rate of new infections, the HIV/AIDS burden in the country remains huge and vigilant efforts must be continued if this burden is to further decrease.

Traditionally the government, supported by its international partners as well as local non-government organizations and the community has borne the brunt of the costs of containing the epidemic in Uganda. While the corporate sector in the country has financially contributed towards the costs of some of the interventions that are currently in place to combat the HIV epidemic, there is largely a paucity of sustained and systematic corporate leadership in providing comprehensive HIV/AIDS programmes for their employees.

A survey done by the authors of this paper reveals that most programmes undertaken in the private sector are of limited scope. We argue that there is more the corporate sector can do to more equitably share the HIV/AIDS burden, without necessarily jeopardizing its primary role - namely to maximize returns to shareholders.

This paper proposes a conceptual framework of how companies can approach the issue of HIV/AIDS within their workforce and suggests that providing more comprehensive interventions may in some instances result in substantial cost savings through the prevention or at least delay of HIV/AIDS related consequences such as: frequent absences from work, erosion of company skills and knowledge through key employee deaths, and the costs of hiring and training replacements etc. This ultimately could result in positive financial returns to those companies that choose to pursue work place led HIV/AIDS control and prevention programmes.

  相似文献   
29.
Sera from leprosy patients across the clinical spectrum, healthy contacts, tuberculosis patients, and healthy donors were tested for their reactivity with antigens of mycobacterial strain ICRC (a cultivable mycobacterium) and Mycobacterium leprae by immunoprecipitation technique. Using M. leprae antigens, it was not possible to distinguish between reactivities of sera from lepromatous, borderline lepromatous, borderline tuberculoid, and tuberculoid leprosy patients. All these sera identified M. antigens with molecular masses of 47, 36, 21, and 14 kDa. When the same sera were tested for their reactivities with antigens of mycobacterial strain ICRC, several differences were observed. The 21-kDa antigen of mycobacterial strain ICRC was exclusively precipitated by sera from all lepromatous leprosy patients and from those undergoing erythema nodosum leprosum reaction. Sera from all the other donors tested failed to identify the 21-kDa antigen of mycobacterial strain ICRC. The 14-kDa protein of mycobacterial strain ICRC was identified by sera from a few lepromatous leprosy patients (5 of 26) and all their contacts. Our studies indicate that antigens present on cultivable mycobacteria rather than species-specific antigens may prove to be useful in the serodiagnosis of leprosy.  相似文献   
30.

Background

Currently, there is renewed interest in the role community participation can play in Primary Health Care (PHC) programmes such as the delivery of effective anti-TB treatment to patients in high-burden settings.

Objectives

To explore the feasibility of community participation in a high-burden Tuberculosis Control Programme and to establish how supervision of treatment by lay volunteers compares with other methods of tuberculosis treatment delivery in the Northern Cape province of South Africa.

Methods

Prospective study involving 769 patients with confirmed pulmonary TB who were followed-up over a one-year period. Questionnaire interviews were also carried out with 135 lay volunteers participating in the TB programme.

Results

One-third of the TB patients in the study received their treatment from lay volunteers in the community. Treatment outcomes for new patients supervised from the community were found to be equivalent to those who received treatment through other modes of treatment delivery (RR=1.04[0.94–1.16], p=0.435). For the re-treatment patients, community-based treatment was found to be superior (RR=5.89[2.30–15.09], p<0.001), to self-administered therapy.

Conclusions

Health care planners should consider community participation as a viable way of ensuring accessibility and effectiveness in PHC programmes. There is need for more research into ways of achieving sustainability in resource-limited but high disease burden settings.  相似文献   
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