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21.
We describe a woman whose fatal post-liver transplantation cerebral edema was unexpected and of unusual pathogenesis. Her severe cerebral edema is of considerable pathophysiologic interest: 1) it developed in the setting of marked anasarca and persistent hypernatremia, and 2) although hepatic function was poor, it was not considered sufficiently deranged to induce cerebral edema. Furthermore, there was no histologic evidence of hepatic rejection or antemortem hepatic necrosis. We postulate that an impairment of the blood brain barrier in association with a degree of hepatic dysfunction insufficient by itself to cause cerebral edema permitted the brain interstitial fluid volume to increase pari passu with ECF expansion. Cytotoxic cerebral edema and vascular engorgement may also have contributed to a life-threatening increase in intracranial pressure.  相似文献   
22.
BACKGROUND: Ten percent of gastric cancer (GC) cases are familial, with one third resulting from a mutation in the tumor suppressor gene CDH1. Loss of this important structure can result in hereditary diffuse gastric cancer (HDGC), which carries a high mortality if early diagnosis is not made. Despite its clear genetic origin, optimal management of HDGC family members is controversial, as the utility and efficacy of current cancer screening programs for mutation carriers are unproven. METHODS: A 53-year-old Caucasian woman was initially seen for genetic screening because multiple family members had mutations of the CDH1 gene. Her pedigree analysis demonstrated 4 generations of gastric cancer, and 2 of the generations carried the CDH1 germline mutation, consistent with HDGC. At endoscopy, the patient's gastric mucosa was normal and random biopsies were also normal. The patient underwent a laparoscopic total gastrectomy. RESULTS: The gross examination of her stomach appeared normal. On histologic examination, however, the stomach was found to have diffuse (signet ring cell) adenocarcinoma in-situ with 11 microscopic foci of invasive adenocarcinoma limited to the lamina propria. CONCLUSION: Our case is the first reported prophylactic total gastrectomy utilizing a laparoscopic approach, and it highlights the importance of taking a thorough family history and obtaining a pedigree analysis. Endoscopic screening in HDGC cannot rule out diffuse GC, because the stomach and biopsies can be normal despite the presence of adenocarcinoma. Therefore, our case supports the recommendation for prophylactic gastrectomy in HDGC.  相似文献   
23.
An Australian school of nursing's attempt to introduce an evaluation process required by management for clinical educators involved in undergraduate preregistration education is discussed Reliance on student feedback and clinical agencies' perceptions of the quality of teaching were seen as inadequate mechanisms for evaluation The evaluation process adopted incorporated observation of the educators together with self-reflection on their performance We conclude that post-briefings were poorly used and generally not reflective Educators relied heavily on their clinical skills and used a limited range of teaching strategies Whilst evaluation of clinical educators was time consuming and therefore costly, it is argued that it is essential to the integrity of the course The evaluation process has provided direction for support and development of clinical educators within the context of the curriculum  相似文献   
24.
Summary: Bovine immunoglobulins are made from genes belonging to a small family of closely related Vh, genes. In this respect cattle resemble all species of domesticated mammals, which also use one VH family The family, named BoVH1, is homologous to the mouse Q52 family, and there are no more than 20 genes of this family in the bovine genome. Another feature of bovine heavy chains is the use of long CDR3s, which have an average of 21 codons. It seems that there are several families of long, closely related D genes rich in glycine and tyrosine responsible for this length. Sequences described as targets for mutations in other species can be found in CDR1, CDR2, and the putative D genes. The mutation mechanism starts at some point between late fetal stage and birth and seems to be antigen Independent. Diversity seems to be generated by hypermutation, although other mechanistns cannot be discomited at this time. Contrary to humans and mice, which have several Vh gene families comprising more than 100 genes, cattle use only a few genes and long CDR3s followed by somatic mutation to generate the necessary diversity to recognize the universe of antigens they will encounter during their life.  相似文献   
25.
The development and implementation of effective community support systems are goals of many public mental health authorities who are attempting to shift the focus and dollars for mental health services from inpatient to community care. This article presents the results of a survey which asked 90 community mental health agency case managers to assess the community support and residential needs of over 1400 of their clients. Medication monitoring and therapy were rated high priority needs. Psychosocial treatment, day and vocational activities also ranked high. Survey responses regarding residential services indicated a need for more supported and supervised options.The study reported was a collaborative effort by county and agency staff.  相似文献   
26.
Comparative study of brain morphology in ants   总被引:1,自引:0,他引:1  
Brain morphology, with special attention to the three dimensional form of the corpora pedunculata, was studied in thirteen species of ants, representing four subfamilies of Formicidae. The results can be summarized as follows. (1) The neural systems processing optic and olfactory information differ in the evolutionary history among the studied taxa. A positive correlation can be demonstrated in the phylogenetic history of the corpora pedunculata, central body, cerebral bridge and olfactory lobe, but not the optic lobe. Ant species with very large eyes and thus, probably, highly developed vision, show gigantic optic lobes, with no exaggeration of any other brain structure. (2) More social species have more complex chemical communication systems and better developed corpora pedunculata (more surface in foldings of the calyces) and olfactory lobes; however, this tendency seems to reverse in highly social species with a sophisticated polymorphic caste system: individuals of these species are generally less developed neurally. (3) There are differences between the form of the internal and external calyces of the corpora pedunculata, and these differences are proportionately more pronounced in species with complex social organization. (4) Individuals from different worker castes of the same species differ in their brain morphology, but each species shows a different pattern of variation among their castes. (5) Brain structure shows characteristic marks due to the different phylogenetic developments in the taxa studied. For example the trends in brain volume-body size ratio are different for the various subfamilies, suggesting a divergent phylogenetic history.  相似文献   
27.
A national study was conducted between 1991 and 1994 to explore and describe the changing role of the nurse teacher following the introduction of Project 2000 pre-registration nursing courses. Multiple methods were used to collect data from a wide variety of respondents (nurse teachers, midwife teachers, clinical nurses, health service managers and higher education lecturers). This paper presents the findings relating to the impact of Project 2000 and the move into higher education on the continuing educational needs of nurse teachers. Views on college strategies for staff development, the changing nature of teachers'academic and professional development needs and the problems of the conflicting demands experienced are reported. The research highlights the need for clinical credibility to be clearly defined in relation to nurse teachers and for educational institutions to place more emphasis on teachers'clinical development if the rhetoric of policy is to become a reality.  相似文献   
28.
Although negative symptoms were traditionally considered to be unresponsive to neuroleptic medication, recent studies have demonstrated that negative symptoms do improve during neuroleptic treatment and that such improvement tends to occur concurrently with improvement in positive symptoms. Clozapine is an atypical neuroleptic that is effective in a significant proportion of otherwise neuroleptic-nonresponsive schizophrenic patients; in contrast to conventional neuroleptics, clozapine is also purported to possess unique efficacy in the amelioration of negative symptoms. How clozapine-associated reduction in negative symptoms relates to change in positive symptoms is not clear. To study the relationship between change in positive and negative symptoms during clozapine treatment, we monitored symptomatology in 40 DSM-III-R schizophrenic patients before and about 8 weeks after a trial of clozapine. Both positive and negative symptoms improved significantly. There was a significant correlation (r = .63,p <.01) between change in positive symptoms and change in negative symptoms; as with conventional neuroleptics, negative symptoms improved concomitantly with positive symptoms during clozapine treatment. Clozapine's apparent greater efficacy on negative symptoms may be related to its greater efficacy on positive symptoms in otherwise neuroleptic-refractory patients and its lesser propensity to cause extrapyramidal side-effects.  相似文献   
29.
An attempt was made in two experiments to reinvestigate the effects of the antiandrogen cyproterone acetate (CA) on mouse social behavior in a variety of ethologically-assessed paired encounters. The data confirm that CA reduces offense (threat and attack) in animals when both subjects receive the material but that CA has no such action in other pairings. This suggests that CA's major suppressive effect on "hostility" is expressed in mice via a reduction in "attack-promoting" pheromone production. Indeed, there was evidence in the more chronic study that CA, could augment (via a central mechanism?) offense in subjects paired with docile anosmic opponents. Changes in defense were largely responses to variations in the degree of attack to which animals were subjected. The antihormone also had actions on other aspects of behavior including sexual activity, social investigation and immobility in such tests. CA had a potent suppressive action on the weights of sex accessory glands. The data do not suggest that CA can be used as a specific antihostility agent.  相似文献   
30.
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