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991.
992.
1 临床资料1.1 病例报告 患者 ,男 ,2 4岁 .因患感冒来我院内二科门诊治疗 .医师处方用 :穿琥宁注射液 2 0 m L+5 0 g· L- 1葡萄糖注射液 2 5 0 m L ,静脉滴注 ,1次 / d;硫酸妥布霉素注射液 16万 U+9g· L- 1氯化钠注射液 2 5 0 m L,静脉滴注 ,1次 / d.从处方上看 ,上述用药方案是可行的 .但在护理操作过程中 ,却出现了不同液体瓶里的两种药液在输液管内相遇时 ,发生了化学反应 ,生成了白色絮状沉淀[1 ] .幸好护理人员及时发现 ,中止输液 ,避免了一场事故的发生 .1.2 调查报告 我们对本院门诊和内二科病房作了一次调查 .1999— 0 6… 相似文献
993.
BACKGROUND: Variation in number, characteristics and management of deliberate self-harm (DSH) patients presenting to hospital during the 24-h cycle and day of the week may have implications for patient services. We have investigated how patient characteristics and clinical management of DSH episodes vary according to hour and day of presentation. METHODS: Time of presentation was studied in 5348 DSH patients who presented to a general hospital following 9101 episodes during a 6-year period. Patient characteristics were identified through routine clinical monitoring. RESULTS: Presentations varied markedly during the 24-h cycle, ranging from a peak between 8 pm and 3 am (average hourly rate of 6.6% of all episodes) to a low between 4 am and 10 am (1.4%). The majority (72.0%) occurred outside office hours. DSH associated with alcohol use and interpersonal problems was more frequent during the late evening or night, and at the weekend. A greater proportion of daytime presentations involved high suicide intent (although a larger number of high intent acts presented at other times), and more were admitted and assessed. LIMITATIONS: This study was based on DSH presentations to one hospital. Time and date of presentation and of psychosocial assessment, not time of DSH, were available for analysis. CONCLUSIONS: Peak times for DSH presentations are at night and the weekend, suggesting that specialist DSH services in general hospitals should be available 24 h a day, 7 days a week. Time of presentation should not be used as a proxy measure of suicide intent. 相似文献
994.
Spinocerebellar ataxia type-1 and spinobulbar muscular atrophy gene products interact with glyceraldehyde-3-phosphate dehydrogenase 总被引:4,自引:2,他引:4
Koshy B; Matilla T; Burright EN; Merry DE; Fischbeck KH; Orr HT; Zoghbi HY 《Human molecular genetics》1996,5(9):1311-1318
Spinocerebellar ataxia type1 (SCA1) is one of several neurodegenerative
disorders caused by expansions of translated CAG trinucleotide repeats
which code for polyglutamine in the respective proteins. Most hypotheses
about the molecular defect in these disorders suggest a gain of function,
which may involve interactions with other proteins via the expanded
polyglutamine tract. In this study we used ataxin-1, the SCA1 gene product,
as a bait in the yeast two-hybrid system and identified the glycolytic
enzyme glyceraldehyde-3-phosphate dehydrogenase as an ataxin-1 interacting
protein. In addition, the yeast two hybrid data demonstrate that wild type
and mutant ataxin-1 form homo and heterodimers. Physical interaction
between GAPDH and ataxin-1 was also demonstrated in vitro. To investigate
if GAPDH might interact with other glutamine repeat-containing proteins
involved in neurodegenerative disorders, we tested its binding to the
androgen receptor which is mutated in spinobulbar muscular atrophy. The
androgen receptor interacts with GAPDH both in the yeast two-hybrid system
and in vitro. The binding of both ataxin-1 and the androgen receptor to
GAPDH does not vary with the length of the polyglutamine tract. While
provocative, these findings do not address the selective neuronal loss in
each of these disorders in light of the wide expression patterns of GAPDH
and the respective polyglutamine containing proteins. Nonetheless, such
interactions may increase the susceptibility of specific neurons to a
variety of insults and initiate degeneration.
相似文献
995.
van Bergen MA Dingle KE Maiden MC Newell DG van der Graaf-Van Bloois L van Putten JP Wagenaar JA 《Journal of clinical microbiology》2005,43(12):5888-5898
Campylobacter fetus can be divided into the subspecies C. fetus subsp. fetus and C. fetus subsp. venerealis. C. fetus subsp. fetus causes sporadic infections in humans and abortion in cattle and sheep and has been isolated from a variety of sites in different hosts. C. fetus subsp. venerealis is host restricted, being isolated mainly from the genital tracts of cattle, and is the causative agent of bovine genital campylobacteriosis. Despite differences in niche preference, microbiological subspecies differentiation has proven difficult. Different typing methods divided C. fetus isolates into different subgroups, depending on the methods used. The relative value of these methods can be assessed by the evolutionary relationship of isolates belonging to the genus; therefore, we developed a multilocus sequence typing (MLST) scheme for C. fetus. This scheme was applied to 140 C. fetus isolates previously typed by amplified fragment length polymorphism (AFLP) analysis. A total of 14 different sequence types (STs) were identified, and these exhibited low levels of inter-ST genetic diversity, with only 22 variable sites in 3,312 nucleotides. These MLST data indicate that C. fetus is genetically homogeneous compared to the homogeneity of other Campylobacter species. The two C. fetus subspecies were extremely closely related genetically, but ST-4 was associated only with C. fetus subsp. venerealis, which represents a "bovine" clone. The C. fetus subsp. fetus isolates studied were more diverse in terms of their STs, and the STs correlated with epidemiological relationships. Congruence was observed among C. fetus subspecies, sap type, and ST; therefore, MLST confirms that mammalian C. fetus is genetically stable, probably as result of the introduction of a single ancestral clone into a mammalian niche. 相似文献
996.
Background
Regression of established tumors can be induced by adoptive immunotherapy with tumor draining lymph node lymphocytes activated with bryostatin and ionomycin. We hypothesized that tumor regression is mediated by a subset of the transferred T lymphocytes, which selectively infiltrate the tumor draining lymph nodes and proliferate in vivo.Results
Adoptive transfer of B/I activated tumor draining lymphocytes induces regression of advanced 4T1 tumors, and depletion of CD8, but not CD4 T cells, abrogated tumor regression in mice. The predominant mediators of tumor regression are CD8+ and derived from CD62L- T cells. Transferred lymphocytes reached their peak concentration (10.5%) in the spleen 3 days after adoptive transfer and then rapidly declined. Adoptively transferred cells preferentially migrated to and/or proliferated in the tumor draining lymph nodes, peaking at day 5 (10.3%) and remained up to day 28. CFSE-stained cells were seen in tumors, also peaking at day 5 (2.1%). Bryostatin and ionomycin-activated cells proliferated vigorously in vivo, with 10 generations evident in the tumor draining lymph nodes on day 3. CFSE-stained cells found in the tumor draining lymph nodes on day 3 were 30% CD8+, 72% CD4+, 95% CD44+, and 39% CD69+. Pre-treatment of recipient mice with cyclophosphamide dramatically increased the number of interferon-gamma producing cells.Conclusions
Adoptively transferred CD8+ CD62Llow T cells are the principal mediators of tumor regression, and host T cells are not required. These cells infiltrate 4T1 tumors, track preferentially to tumor draining lymph nodes, have an activated phenotype, and proliferate in vivo. Cyclophosphamide pre-treatment augments the anti-tumor effect by increasing the proliferation of interferon-gamma producing cells in the adoptive host. 相似文献997.
998.
J E Ottenweller R J Servatius W N Tapp S D Drastal M T Bergen B H Natelson 《Physiology & behavior》1992,51(4):689-698
The chronic stress state has previously been defined as persistent visceral arousal coupled with behavioral abnormalities. To determine the number of stressor exposures necessary to induce a chronic stress state, male rats were given 2 hours of inescapable shock on 10, 7, 4, or 3 consecutive days. The 3-day stress group had the most pervasive changes in the variables measured: persistently elevated basal plasma corticosterone (CORT), continued weight loss in the post-stressor period, and abnormal behavior. More exposures to the stress regimen did not produce higher CORT levels or greater behavioral changes. Acutely stressed rats, exposed to 1 day of inescapable shock, had persistent CORT elevations without the other changes seen in the 3-day stress group. The data suggest that 3 days of our stress regimen are sufficient to produce a state of chronic stress and that some signs of this state begin to appear as early as the first exposure to our inescapable stress regimen. 相似文献
999.
Depotentiation of intact rat cardiac muscle unmasks an Epac‐dependent increase in myofilament Ca2+ sensitivity 下载免费PDF全文
Sarbjot Kaur Cherrie HT Kong Mark B Cannell Marie‐Louise Ward 《Clinical and experimental pharmacology & physiology》2016,43(1):88-94
Recently, a family of guanine nucleotide exchange factors have been identified in many cell types as important effectors of cyclic adenosine 3′,5′‐monophospahte (cAMP) signalling that is independent of protein kinase A (PKA). In the heart, investigation of exchange protein directly activated by cAMP (Epac) has yielded conflicting results. Since cAMP is an important regulator of cardiac contractility, this study aimed to examine whether Epac activation modulates excitation–contraction coupling in ventricular preparations from rat hearts. The study used 8‐(4‐chlorophenylthio)‐2′‐O‐methyladenosine‐3′, 5′‐cyclic monophosphate (cpTOME), an analogue of cAMP that activates Epac, but not PKA. In isolated myocytes, cpTOME increased Ca2+ spark frequency from about 7 to 32/100 μm3/s (n = 10), P = 0.05 with a reduction in the peak amplitude of the sparks. Simultaneous measurements of intracellular Ca2+ and isometric force in multicellular trabeculae (n = 7, 1.5 mmol/L [Ca2+]o) revealed no effect of Epac activation on either the amplitude of Ca2+ transients (Control 0.7 ± 0.1 vs cpTOME 0.7 ± 0.1; 340/380 fura‐2 ratio, P = 0.35) or on peak stress (Control 24 ± 5 mN/mm2 vs cpTOME 23 ± 5 mN/mm2, P = 0.20). However, an effect of Epac in trabeculae was unmasked by lowering extracellular [Ca2+]o. In these depotentiated trabeculae, activation of the Epac pathway increased myofilament Ca2+ sensitivity, an effect that was blocked by addition of KN‐93, a Ca2+/calmodulin‐dependent protein kinase II (CaMK‐II) inhibitor. This study suggests that Epac activation may be a useful therapeutic target to increase the strength of contraction during low inotropic states. 相似文献
1000.
ABCC6/MRP6 mutations: further insight into the molecular pathology of pseudoxanthoma elasticum 总被引:5,自引:0,他引:5
Hu X Plomp A Wijnholds J Ten Brink J van Soest S van den Born LI Leys A Peek R de Jong PT Bergen AA 《European journal of human genetics : EJHG》2003,11(3):215-224
Pseudoxanthoma elasticum (PXE) is a hereditary disease characterized by progressive dystrophic mineralization of the elastic fibres. PXE patients frequently present with skin lesions and visual acuity loss. Recently, we and others showed that PXE is caused by mutations in the ABCC6/MRP6 gene. However, the molecular pathology of PXE is complicated by yet unknown factors causing the variable clinical expression of the disease. In addition, the presence of ABCC6/MRP6 pseudogenes and multiple ABCC6/MRP6-associated deletions complicate interpretation of molecular genetic studies. In this study, we present the mutation spectrum of ABCC6/MRP6 in 59 PXE patients from the Netherlands. We detected 17 different mutations in 65 alleles. The majority of mutations occurred in the NBF1 (nucleotide binding fold) domain, in the eighth cytoplasmatic loop between the 15th and 16th transmembrane regions, and in NBF2 of the predicted ABCC6/MRP6 protein. The R1141X mutation was by far the most common mutation identified in 19 (32.2%) patients. The second most frequent mutation, an intragenic deletion from exon 23 to exon 29 in ABCC6/MRP6, was detected in 11 (18.6%) of the patients. Our data include 11 novel ABCC6/MRP6 mutations, as well as additional segregation data relevant to the molecular pathology of PXE in a limited number of patients and families. The consequences of our data for the molecular pathology of PXE are discussed. 相似文献