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41.
Objective: Vasoconstriction during anxiety reduces fetal oxygenation and leads to hypoxia. Hypoxia in turn results in increase of the number of nucleated red blood cells (NRBCs) in the cord blood. The present study aimed to assess the effect of decreasing maternal anxiety on fetal oxygenation and NRBCs count in the cord blood. Methods:. In this study, 150 women were randomly divided into two intervention groups [supportive care and acupressure in BL32 (bladder) acupoint] and a control group (hospital routine care). The infants'' cord blood was investigated regarding the number of NRBCs and the intensity of hypoxia after birth. Then, the data were entered into the SPSS statistical software (v. 16) and analyzed using ANOVA, Chi-square test, and logistic regression analysis. Findings : The significant difference was found between the two groups regarding the number of NRBCs counted in the peripheral blood smear (P<0.001). Besides, a significant relationship was observed between the length of the first and second stages of labor and the number of NRBCs in the cord blood (P=0.01). Also, a significant association was observed between the type of delivery and the number of NRBCs in the cord blood in both intervention (P<0.001) and control groups (P=0.03). Conclusion: Doula supportive care and acupressure at BL32 point reduced the length of labor stages as well as the anxiety level. Also, nucleated red blood cells were less in the 2 groups of intervention than in control group. Regarding the fact that nucleated red blood cells cannot be the only factor for hypoxia predicting, for affirmation of this theory study with higher sample size and survey of mothers at high risk are needed.Key Words: Acupressure; Anxiety; Delivery Outcome; Doula  相似文献   
42.

Introduction

Cone-beam computed tomographic (CBCT) imaging is a valuable tool for endodontic therapy. The aim of this study was to verify whether clinical use of CBCT imaging can accurately acquire parameters concerning molar pulp chamber landmarks, which are important data to help start a successful access cavity and avoid iatrogenic furcation perforations.

Methods

Seventy CBCT images were used to measure 118 maxillary and 104 mandibular molars. The following vertical distances were measured: from the cusp tip/central fossa to the pulp chamber floor, to the pulp chamber ceiling, and to furcation; from the pulp chamber ceiling to furcation; from the pulp chamber floor to furcation; and the pulp chamber height. Measurements were read to the nearest 0.05 mm.

Results

The measurements were as follows: the pulp chamber floor to furcation (maxillary molar: 1.97 ± 0.58 [mean ± standard deviation, mm], mandibular molar: 2.24 ± 0.47), the pulp chamber ceiling to furcation (maxillary molar: 4.09 ± 0.68, mandibular molar: 3.78 ± 0.70), the central fossa to furcation (maxillary molar: 8.78 ± 0.79, mandibular molar: 8.53 ± 0.65), the central fossa to the pulp chamber floor (maxillary molar: 6.81 ± 0.83, mandibular molar: 6.29 ± 0.65), the central fossa to the pulp chamber ceiling (maxillary molar: 4.69 ± 0.59, mandibular molar: 4.75 ± 0.56); and pulp chamber height (maxillary molar: 2.12 ± 0.81, mandibular molar: 1.53 ± 0.68). Measurements showing the least standard deviation were the central fossa to furcation and the central fossa to the pulp chamber floor.

Conclusions

CBCT imaging may be used for precise clinical acquisition of the pulp chamber landmark measurements for molars thereby facilitating successful access cavity.  相似文献   
43.
44.
Type 2 diabetes increases the risk of developing cardiovascular (CV) complications such as myocardial infarction, heart failure, stroke, peripheral vascular disease, and CV-associated mortality. Strict glycemic control in diabetics has shown improvement in microvascular complications related to diabetes but has been unable to demonstrate major effects on macrovascular complications including myocardial infarction and stroke. Conventional therapies for diabetes that include insulin, metformin, sulfonylureas (SU), and alpha-glucosidase inhibitors have limited and/or controversial data on CV safety based on observational studies not designed or powered to assess CV safety of these medications. In 2008, the US Food and Drug Administration (FDA) revised regulations for the approval of medications for type 2 diabetes by requiring that enough CV events are accrued prior to approval to rule out an upper 95 % confidence interval (95 % CI) for HR of 1.8 for CV events, followed by ruling out an upper 95 % CI for HR of 1.3 in the post-approval period. To date, novel diabetes therapies including peroxisome proliferator-activated receptor (PPAR) gamma agonists, dipeptidyl peptidase-4 (DPP4) inhibitors, glucagon-like peptide 1 (GLP 1) analogs, and sodium-glucose transporter-2 (SGL2) inhibitors have been evaluated in CV safety trials. Results from the first major CV outcome studies in type 2 diabetes, SAVOR-TIMI 53 and EXAMINE, have shown that neither saxagliptin nor alogliptin had increases in major CV events relative to placebo in high-risk patients. Ongoing and future trials will elucidate the CV safety for other DPP-4 inhibitors compared to SUs and the GLP-1 agonists versus placebo.  相似文献   
45.
Lee JM  Vo KD  An H  Celik A  Lee Y  Hsu CY  Lin W 《Annals of neurology》2003,53(2):227-232
The purpose of this study was to explore the feasibility of obtaining magnetic resonance-measured cerebral metabolic rate of oxygen utilization (MR-CMRO(2)) in acute ischemic stroke patients. Seven stroke patients were serially imaged: 4.5 +/- 0.9 hours (tp1), 3 to 5 days (tp2), and 1 to 3 months (tp3) after symptom onset. Diffusion-weighted, perfusion-weighted, and multiecho gradient-echo/spin-echo images were acquired; cerebral blood flow and oxygen extraction fraction maps were obtained from which CMRO(2) was calculated as the product of cerebral blood flow and oxygen extraction fraction. The final infarct lesions obtained from tp3 T2-weighted images and the "penumbra" obtained from the tp1 perfusion-weighted image-defined lesion were coregistered onto tp1 CMRO(2) maps. CMRO(2) values in the region of brain that eventually infarcted were reduced to 0.40 +/- 0.24 of the respective region on the contralateral hemisphere. The "salvaged penumbra" defined by the area of mismatch between the final infarct and the tp1 perfusion-weighted lesion demonstrated an average CMRO(2) value of 0.55 +/- 0.11 of the contralateral hemisphere. Although our results are preliminary and require further evaluation, the ability to obtain in vivo measurements of MR-CMRO(2) noninvasively potentially can provide information for determining brain tissue viability in acute ischemic stroke patients.  相似文献   
46.
47.
The use of isotopic substitution to delay the oxidative metabolism of the anesthetic propofol 1 was studied. The aromatic hydrogens of propofol 1 were replaced by deuterium to produce the mono- and trideuterated derivatives 4 and 5. In vitro metabolic studies on human hepatic microsomes showed no isotopic effect in the para hydroxylation of propofol, and 1, 4, and 5 display similar hypnotic activity and toxicity in mice.  相似文献   
48.
Mesenchymal cell movement is normally constrained; however, fibronectin can provide a pathway for stromal cell migration during embryogenesis, morphogenesis, and wound healing. Cells can adhere to fibronectin via integrin and nonintegrin receptors, which bind multiple unique peptide sequences. Synthetic peptides and recombinant proteins were used to delineate the functional domains needed for human fibroblast migration over fibronectin. The 9th and 10th fibronectin type III repeats, which contain RGD and PHSRN synergy cell attachment sequences, support almost maximal fibroblast attachment, but not migration of primary dermal fibroblasts. Specific sequences within the heparin domain and the IIICS region are also required for migration. These findings predict and additional data confirm the necessity for the cooperation of multiple integrin and nonintegrin receptors for fibroblast migration on fibronectin. Such stringency of migration most likely imposes an immense constraint on normal mesenchymal cell mobility in unperturbed tissue. Loss of such restraint may be critical for the migration cancer cells through the extracellular matrix.  相似文献   
49.
BACKGROUND: Because altered immune responses may be a risk factor for persistent diarrhea, various aspects of the immune response were examined to elucidate the underlying immune mechanisms that may be involved in the development of persistent diarrhea. METHODS: Children (7-12 months of age) with watery diarrhea for 6 to 8 days from the Dhaka Hospital of the International Centre for Diarrheal Disease Research, Bangladesh (ICDDR,B), were enrolled. Children were classified as having acute diarrhea (AD) or persistent diarrhea (PD) if diarrhea resolved within 14 days or persisted for more than 14 days, respectively. Uninfected control children (n = 13), from the Nutrition Follow-Up Unit of ICDDR,B were also enrolled. Of the 123 children with diarrhea who were enrolled, 85 had AD and 38 had PD. Comparisons were performed for clinical features, nutritional status (weight for age, plasma transferrin, and serum albumin levels), and immune responses: neutrophil function; peripheral blood mononuclear cell function, delayed-type hypersensitivity (DTH) responses, plasma levels of immunoglobulins, tumor necrosis factor-alpha, and interferon-gamma. Univariate analyses were conducted to assess differences among the three groups of children and between children with AD and PD. Logistic regression was performed to determine risk factors for PD. RESULTS: There were no differences in clinical features and nutritional status among the groups of children studied. More children in whom PD developed had a negative DTH response to tuberculin than those with AD (P = 0.021). Also, a negative DTH response to tuberculin was a significant risk factor for PD (odds ratio [OR] = 3.8, 95% confidence interval [CI] = 1.5-9.9). CONCLUSIONS: Children with acute diarrhea with a negative DTH response to tuberculin are more likely to have development of persistent diarrhea.  相似文献   
50.
Salmonella species include facultative intracellular pathogens which reside preferentially within cells of the host's reticulo-endothelial system. Resistance to Salmonella involves a collaboration between cells of the innate and adaptive immune systems, and protective immunity requires cell-mediated and humoral-immune responses. CD40-CD154 interactions are of central importance in the induction of cellular immune responses. In the present study, CD154-deficient (CD154(-/-)) mice were used to assess the role of CD40-CD154 interactions in immunity to Salmonella infection. Compared to C57BL/6 (CD154(+/+)) controls, CD154(-/-) mice were hypersusceptible to infection by an attenuated strain of Salmonella enterica serovar Typhimurium (S. typhimurium), as evidenced by a significantly decreased survival rate. CD154(-/-) mice exhibited a defect in the production of IFN-gamma and NO in the acute phase of the disease, which resulted in a failure to control bacterial replication. We conclude that intercellular communications via the CD40-CD154 pathway play a critical role in the induction type-1 cytokine responses and protection against primary infections with attenuated Salmonella.  相似文献   
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