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排序方式: 共有1054条查询结果,搜索用时 15 毫秒
1.

Objective

To analyse and understand vaccination hesitancy discourses, particularly those of people who have decided not to vaccinate their sons and daughters.

Methods

Qualitative study of five individual interviews and two focus groups with people who chose not to vaccinate their children in the province of Granada (Spain).

Results

Mothers and fathers manifest a system of health beliefs different to the biomedical paradigm. From an ethical point of view, they justify their position based on the right to autonomy and responsibility for their decisions. Alleged specific reasons: they doubt administration of several vaccines simultaneously at an early age in a systematic way and without individualising each case; they fear adverse effects and do not understand the variations of the vaccination schedule.

Conclusions

These vaccination hesitancy discourses respond to the individual vs collective conflict; parents defend their right to bring up their children without any interference from the state and focus their responsibility on the individual welfare of their sons and daughters, regardless of the consequences that their actions might have on the collective. In their management of risks, they consider those derived from vaccination more relevant than the individual or collective consequences of not doing so. The vaccines generating most doubts are the more controversial ones within the scientific world. Transparency in communication of adverse effects; authorities respect for other health/disease concepts; banishment of the term “anti-vaccines” from the media and scientific vocabulary, and developing spaces for dialogue are bridges to be built.  相似文献   
2.
Salmon (Oncorhynchus kisutch) somatostatin (sSS; 4 or 8 ng/g body wt) or synthetic Gillichthys urotensin II (UII; 2 or 4 ng/g body wt) were injected intraperitoneally into juvenile freshwater coho salmon. Both sSS and UII caused a dose-dependent increase in plasma free fatty acids (FFA) which diminished with time. sSS induced an initial (1 hr) transient hyperglycemia. By contrast, UII tended to induce hypoglycemia, this effect being significant 5 hr after injection of the higher dose. Both sSS and UII depressed plasma insulin titers 1 hr after injection. By 3 hr, the sSS-associated insulin depression was no longer observed. UII treatment induced a hyperinsulinemia which was present 3 and 5 hr after peptide administration. Although no decreases in liver total lipid concentration or in mesenteric fat total tissue mass were observed, lipolytic enzyme activity within each depot was significantly enhanced by both peptides. Neither sSS nor UII altered 3H2O incorporation into fatty acids or neutral lipids. However, enhanced lipogenesis, particularly by UII, was indicated by increased NADPH production resulting from glucose-6-phosphate dehydrogenase activity. Both sSS and UII enhanced glucose mobilization, as indicated by decreased liver glycogen content and increased liver glucose-6-phosphatase activity. UII, but not sSS, stimulated glycogen synthetase activity. These results suggest that both sSS and UII stimulate hyperlipidemia by enhancing depot lipase activity and that although both factors are potentially gluconeogenetic, sSS seems to be glycogenolytic and hyperglycemic, whereas UII may channel glucose to FFA synthesis.  相似文献   
3.
4.
BACKGROUND. Detection and treatment for rejection after transplantation are based on the identification of myocyte damage upon endomyocardial biopsy. Noninvasive detection of such damage is possible with 111In-labeled monoclonal antimyosin antibodies (MAA). Although the presence and degree of MAA uptake parallels the rejection activity detected by biopsy, the relation between the degree of uptake and the occurrence of severe rejection-related complications has not been previously assessed. METHODS AND RESULTS. Two hundred forty-seven MAA studies were performed coinciding with biopsies in 52 patients 1-71 months after transplantation. A heart-to-lung ratio (HLR) was used as a measure of relative MAA uptake, with an HLR of 1.55 discriminating normal from abnormal studies. Of the 247 antimyosin studies, 149 coincided with absent, 38 with mild, and 60 with moderate rejection at biopsy. HLR was 1.68 +/- 0.27, 1.79 +/- 0.22, and 1.91 +/- 0.33 in the three biopsy groups, respectively (p less than 0.0001). Two hundred thirty-eight of 247 antimyosin studies coexisted with absent rejection-related complications; in nine of 247 patients, such complications were detected (five congestive heart failure episodes due to rejection and four episodes of vascular occlusion, which resulted in five deaths), and mean HLR was 1.74 +/- 0.3 and 2.1 +/- 0.16 in the two groups, respectively (p less than 0.0001). No complications were noted in 193 studies of patients with HLR of less than 2.00, whereas in nine of 45 with HRL of 2.00 or greater, complications occurred (p less than 0.0001). None of the 23 patients prospectively followed since surgery who had a gradual decrease in MAA uptake during the first 3 months showed rejection-related complications, whereas persistent uptake was associated with complications in five of nine patients (p less than 0.001). CONCLUSIONS. No rejection-related complications are seen coinciding with HLR of less than 2.00, whereas patients who have complications have an HLR of more than 2.00. The early 3-month pattern of decreasing MAA uptake is associated with a clinical course free of rejection-related complications, whereas a persistent pattern is a signal of the possibility of such complications.  相似文献   
5.
A comparison was performed between technetium-99m tetrofosmin myocardial perfusion tomography at baseline and after nitrate administration, using a 2-day protocol, and rest-reinjection thallium-201 single-photon emission tomography (SPET) studies in order to assess whether nitrates enhance the detection of viable myocardium with99mTc-tetrofosmin. Fifteen patients with coronary artery disease, previous myocardial infarction and a left ventricular ejection fraction <40% underwent201T1 rest-injection and99mTc-tetrofosmin. baseline-postnitroglycerin (0.4 mg sublingually) SPET studies, within 48 h. Tomograms based on the three spatial planes were divided into 15 segments and regional tracer uptake was quantitatively analysed. Viability was defined as presence of tracer uptake >50% of peak activity on baseline studies or after reversibility. The percentage of peak activity of99mTc-tetrofosmin at baseline correlated with that of 201T1 (r=0.82,P <0.001). On baseline99mTc-tetrofosmin studies, 73 of the 225 segments that were analysed had <50% of peal. activity. Fifteen percent of these segments showed reversibility after nitrate administration, with an increase in99mTc-tetrofosmin uptake from 40%±9% to 57%±9% of peak activity (P=0.003). All reversible segments after nitrate administration had viability criteria on201Tl studies, but 20 segments that were non-viable on99mTc-tetrofosmin. studies were viable on201Tl studies. Using a threshold value of >40% of peak activity, only seven segments remained non-viable on99mTc-tetrofosmin studies. Overall agreement between99mTc-tetrofosmin with nitrates and201Tl-reinjection regarding the presence of myocardial viability was 90%. Detection of myocardial viability with99mTc-tetrofosmin. was enhanced after nitrate administration, correlating with viability criteria observed on thallium studies.  相似文献   
6.
A technique using antibody-coated tubes allows the radioimmunological determination of tetanus antibodies in a simple and rapid way. The procedure is based on the competition for125I-tetanus toxin between the insolubilized antibodies and the antibodies present in the unknown sample. When antibodies and125I labeled tetanus toxin are incubated in the antibody-coated polyethylene vessel the detection limit is about 0.016 IU/ml. When tetanus toxin is preincubated together with its antibody in uncoated vessels before the mixture is transferred to antibody-coated vessels, the sensitivity can be raised about tenfold. The method is especially useful for screening multiple samples.  相似文献   
7.
The purpose of the present study was to evaluate the likelihood and the effect of parent-child factors on communicating about maternal genetic test results for breast/ovarian cancer risk. Subjects were 42 mothers enrolled in a hereditary breast cancer research program who reported on their interactions with 68 target children. Predictor variables (demographic, clinical, and psychological) were assessed at baseline after mothers participated in a comprehensive genetic counseling/education session and provided a blood sample for BRCA1/2 mutation analysis. Maternal communication of test results to children was assessed 1 month after mothers learned their mutation status. The rate of disclosure to pediatric-age children was 53%. Older children were more likely to be informed of their mothers' test results than were younger children. Maternal disclosure of genetic test results to children was also more likely to occur in the presence of more open parent-child communication styles, though the act of disclosing did not appear to impact communication style. These findings suggest that in addition to developmental phase, family behavioral interactions and communication styles are strongly predictive of whether or not mothers choose to share cancer genetic risk information with their children.  相似文献   
8.
To improve the understanding of the relative importance of serotypes of rotavirus in dehydrating diarrhea, we examined the correlation of clinical characteristics and disease severity with serotype in 2,441 diarrheal episodes among children younger than 2 years of age in rural Bangladesh. Of 764 rotavirus-associated episodes, a single G type (serotype 1, 2, 3, or 4) was determined by oligonucleotide probe in 485 (63%), while 233 episodes were nontypeable. Episodes with G types 2 and 3 were associated with more-severe dehydration than episodes associated with G type 1 or 4 or with nontypeable rotavirus. Episodes did not differ by G type in prevalence of vomiting, copious diarrhea, fever, abdominal pain, or length of treatment center stay. Rotavirus reinfections were detected in seven children, with homologous reinfection (G type 2) in one. Twelve children with diarrhea who died had rotavirus detected in stool specimens within 30 days of death. Children who died were more likely to be malnourished than were surviving children with rotavirus diarrhea. Of 40 specimens tested by polymerase chain reaction, 29 (72.5%) were P type 1, 9 (22.5%) were P type 2, 1 (2.5%) was P type 3, and 1 (2.5%) was nontypeable. One severely symptomatic diarrheal episode was associated with P type 3 rotavirus, a serotype usually found in asymptomatic nursery infections. Although G types 2 and 3 were associated with more-severe dehydration than other serotypes, the differences do not appear to be of major clinical importance. Effective vaccines should protect against all four major G types.  相似文献   
9.
The 42-kDa carboxyl-terminal processing fragment of Plasmodium falciparum merozoite surface protein 1 (MSP-1(42)) is an anti-erythrocytic stage malaria vaccine candidate. In this study, MSP-1(42) was expressed by using the Bombyx mori nuclear polyhedrosis virus-silkworm expression system, and the antigenicity and immmunogenicity of the recombinant protein, Bmp42, were evaluated. The average yield of Bmp42, as determined by a sandwich enzyme-linked immunosorbent assay (ELISA), was 379 microg/ml of infected silkworm hemolymph, which was >100-fold higher than the level attainable in cell culture medium. N-terminal amino acid sequencing revealed that Bmp42 was correctly processed in silkworm cells. Data from immunoblotting, as well as from the inhibition ELISA, suggested that the conformational B-cell epitopes of MSP-1(42) were recreated in Bmp42. Immunization of rabbits with Bmp42 in complete Freund's adjuvant generated high-titer antibody responses against the immunogen. Specificity analyses of the anti-Bmp42 antibodies using several recombinant MSP-1(19) proteins expressing variant and conserved B-cell epitopes suggested that the anti-Bmp42 antibodies recognized primarily conserved epitopes on MSP-1(19). Furthermore, the anti-Bmp42 antibodies were highly effective in inhibiting the in vitro growth of parasites carrying homologous or heterologous MSP-1(42). Our results demonstrated that the baculovirus-silkworm expression system could be employed to express biologically and immunologically active recombinant MSP-1(42) at elevated levels; thus, it is an attractive alternative for producing a protective MSP-1(42) vaccine for human use.  相似文献   
10.
BACKGROUND: Vaginal misoprostol has been shown to be an effective single agent for medical abortion. This randomized, double-blinded, placebo-controlled trial compared a regimen of mifepristone and misoprostol with misoprostol alone for termination of early pregnancy. METHODS: 250 women with gestations < or = 56 days were randomized by a random number table to receive either 200 mg mifepristone orally or placebo followed 48 h later by 800 microg vaginal misoprostol. Administration of misoprostol was repeated every 24 h up to three doses if abortion failed to occur. Abortion success was defined as complete abortion without the use of surgical aspiration. RESULTS: Successful medical abortions occurred in 114 out of 119 subjects (95.7%) after mifepristone followed by vaginal misoprostol. In all, 110 out of 125 subjects (88.0%) successfully aborted after placebo and vaginal misoprostol. The higher success rate of complete abortion with the mifepristone and misoprostol regimen was statistically significant compared with the placebo and misoprostol regimen (P < 0.05). CONCLUSIONS: A regimen of mifepristone and misoprostol was significantly more effective for termination of pregnancies < or = 56 days than misoprostol alone. The 88% efficacy obtained with vaginal misoprostol alone may be clinically acceptable when mifepristone is not available.  相似文献   
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