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991.
992.
993.
The levonorgestrel intrauterine device (LNG-IUD) is a safe, effective, long-acting, reversible contraceptive that reduces unintended pregnancy and decreases heavy menstrual bleeding. Many procedures such as IUD insertion are more challenging in overweight and obese women. The objective of this study was to describe LNG-IUD insertion, continuation, and complications in overweight and obese women in an ethnically diverse population in Hawai‘i. A retrospective cohort study of women who had a LNG-IUD inserted at the University of Hawai‘i, Department of Obstetrics and Gynecology Resident and Faculty practice sites between January 2009 and December 2010 was performed. A total of 149 women were followed. The most commonly reported races were Asian (32%), Native Hawaiian (26%), and non-Hawaiian Pacific Islander (20%). The mean BMI of the study population was 28.4 (standard deviation 7.2) with 37% classified as normal weight, 30% as overweight, and 33% as obese. Overall, 76% of women continued the LNG-IUD 12 months after insertion. No statistically significant difference emerged in 12-month IUD continuation between the BMI groups. Difficult (5%) and failed (3%) IUD insertions were rare for all BMI groups. IUD complications occurred in 9% of women and included expulsion and self-removal. In this diverse population, the majority of women continued to use the LNG-IUD one year after insertion with low rates of difficult insertions and complications.  相似文献   
994.
The adjuvant use of aromatase inhibitors in breast cancer is associated with adverse effects on bone health. We previously reported a decline in bone mineral density (BMD) following the switch from tamoxifen to exemestane in the Intergroup Exemestane Study (IES). Here we report effects of endocrine treatment withdrawal on BMD, bone turnover markers (BTM) and fracture rates. 4,724 patients took part in IES, and 206 patients were included in a bone sub-study. BMD and BTM were assessed pre-randomization, during and after the end of treatment (EOT). To evaluate treatment withdrawal effects, 12- and 24-month post EOT BMD results are available for 122 and 126 patients, respectively. Similar patient numbers had BTM measured post EOT. Following treatment withdrawal, the differences in BMD observed between the two endocrine strategies were partially reversed. At 24 months from EOT, spine BMD increased by 1.53% (95%CI 0.63–2.43; p = 0.001) after stopping exemestane and fell by 1.93% (95%CI −2.91 to 0.95; p = 0.0002) following tamoxifen withdrawal. A similar pattern of changes was observed at the hip. At 2 years post EOT, BMD changes from baseline were similar with both treatment strategies. Corresponding inverse changes in BTM were seen, with an increase following tamoxifen withdrawal and a reduction after exemestane. A higher number of fractures occured during exemestane treatment, but fracture rates were similar after treatment withdrawal. With the switch strategy used in IES, the on treatment adverse bone effects of exemestane are reversed. Ongoing monitoring of BMD is therefore not routinely required.  相似文献   
995.
We have previously shown that young adults living in a rural area of northern Malawi showed greater gamma interferon (IFN-γ) responses to purified protein derivatives (PPD) prepared from environmental mycobacteria than to PPD from Mycobacterium tuberculosis. In order to define the mycobacterial species to which individuals living in a rural African population have been exposed and sensitized, we tested T-cell recognition of recombinant and purified antigens from M. tuberculosis (38 kDa, MPT64, and ESAT-6), M. bovis (MPB70), M. bovis BCG (Ag85), and M. leprae (65 kDa, 35 kDa, and 18 kDa) in >600 non-M. bovis BCG-vaccinated young adults in the Karonga District of northern Malawi. IFN-γ was measured by enzyme-linked immunosorbent assay (ELISA) in day 6 supernatants of diluted whole-blood cultures. The recombinant M. leprae 35-kDa and 18-kDa and purified native M. bovis BCG Ag85 antigens induced the highest percentages of responders, though both leprosy and bovine tuberculosis are now rare in this population. The M. tuberculosis antigens ESAT-6 and MPT64 and the M. bovis antigen MPB70 induced the lowest percentages of responders. One of the subjects subsequently developed extrapulmonary tuberculosis; this individual had a 15-mm-diameter reaction to the Mantoux test and responded to M. tuberculosis PPD, Ag85, MPT64, and ESAT-6 but not to any of the leprosy antigens. We conclude that in this rural African population, exposure to M. tuberculosis or M. bovis is much less frequent than exposure to environmental mycobacteria such as M. avium, which have antigens homologous to the M. leprae 35-kDa and 18-kDa antigens. M. tuberculosis ESAT-6 showed the strongest association with the size of the Mantoux skin test induration, suggesting that among the three M. tuberculosis antigens tested it provided the best indication of exposure to, or infection with, M. tuberculosis.  相似文献   
996.
Familial hypomagnesemia with secondary hypocalcemia (HSH) (MIM 307600) was studied in three inbred Bedouin kindreds from Israel. The three kindreds, one extended and two nuclear families, contained 13 affected individuals, 11 males and two females. Assuming that the individuals affected with hypomagnesemia shared a chromosomal region inherited from a common ancestor, we used a DNA pooling strategy in a genome-wide search for loci which show homozygosity for shared alleles in affected individuals. DNA samples from affected individuals within a single kindred were pooled and used as the template for PCR amplification of short tandem repeat polymorphic markers (STRPs). Pooled DNA from unaffected siblings and parents were used as controls. A shift towards homozygosity was observed in the affected DNA pool compared with the control pools with D9S301 (GATA7D12). Genotyping of individual DNA samples with D9S301 and several flanking markers confirmed linkage to chromosome 9 with maximum LOD scores of 3.4 (theta = 0.05), 3.7 (theta = 0) and 2.3 (theta = 0) for the three families. We have identified a 14 cM interval on chromosome 9 (9q12-9q22.2), flanked by proximal marker D9S1874 and distal marker D9S1807, within which all affected individuals from the three kindreds are homozygous for a shared haplotype. The disease segregates with a common affected haplotype in the three families, suggesting that hypomagnesemia is caused by a common ancestral mutation in these families. Although HSH has been previously reported to be X linked, these linkage data demonstrate that the disorder is an autosomal recessive disease in these kindreds. Mapping of a chromosomal breakpoint in a somatic cell line established from a patient with HSH and a balanced X;9 translocation placed the chromosomal breakpoint in a 500 kb region flanked by D9S1844 and D9S273. Identification of the gene responsible for hypomagnesemia will provide insight into the regulation of this essential cation.   相似文献   
997.
OBJECTIVE: Tracheal gas insufflation (TGI) reduces PaCO(2) by flushing the tracheal and mechanical deadspace, and may have its maximum benefit when TGI gas is unopposed by significant expiratory gas flow. Thus, limiting TGI to the late expiratory period may diminish tracheal exposure to TGI gas while preserving the efficacy of TGI. This study examined the gas exchange consequences of such late-expiratory TGI. DESIGN AND SETTING: Randomized controlled trial, animal study. MATERIALS: Eleven pigs. INTERVENTIONS: After stable lung injury was established using oleic acid 11 pigs were ventilated using a standardized lung protective strategy. Phasic expiratory TGI was applied for 30 min stages during the last 20%, 40%, 60%, and 100% of expiration in random sequence. PaCO(2) was continuously measured via an indwelling blood gas analysis system. MEASUREMENTS AND RESULTS: PaCO(2) at baseline was 86.1+/-4.7 mmHg, and decreased progressively with increasing TGI duration of 20%, 40%, and 60%, but not 100%, of expiration (PaCO(2)=75.7+/-5.2, 68.8+/-3.6, 65.1+/-5.3 and 65.2+/-5.2 mmHg, respectively). For all stages the reduction in PaCO(2) relative to baseline was significant. Trends of increasing PaO(2) and airway pressure with increasing TGI duration were noted and most likely associated with a TGI-induced increase in lung volume. CONCLUSIONS: Under these conditions confining TGI to the final 60% of expiration achieved effective PaCO(2) reduction, not significantly different from panexpiratory TGI, while limiting exposure of the trachea to TGI gas, and reducing the potential for TGI-induced hyperinflation. These findings suggest that TGI is most effectively applied in a phasic manner in late expiration, with its duration titrated to effect.  相似文献   
998.
McCarty  TM; Rajaraman  S; Elder  FF; Gadson  P; Thompson  EB 《Blood》1987,70(5):1665-1672
A new hematopoietic cell line derived from a patient with Philadelphia chromosome (Ph1)-negative myeloblastic leukemia arising from a form of myelodysplastic syndrome (MDS) is described. This cell line, designated TMM, consists of immature cells with the morphological characteristics of young myeloblasts and grows in suspension culture with a doubling time of about 30 hours. By cytochemical analysis the cultured cells were positive for acid phosphatase. They were free of the Epstein-Barr virus-associated nuclear antigen as well as terminal deoxynucleotidyl transferase. Further phenotypic analysis revealed the expression of the myelomonocytic-specific antigen Leu-M1 and receptors for the Fc portion of IgG. Partial differentiation of these cells could be induced by dimethyl sulfoxide, tetradecanoyl phorbol acetate, or hypoxanthine and resulted in cells of the myeloid series expressing lysozyme and receptors for the C3b complement protein. The karyotype was 46,XY, lacked the Ph1 chromosome, and displayed no abnormalities at the light microscopic level. No rearrangement of the bcr-c-abl gene complex was found. This cell line should be useful for studying an important type of the heterogeneous population constituting Ph1-negative myeloblastic leukemia, arising in this instance from MDS, as well as for studying differentiation and proliferation of human pluripotent stem cells.  相似文献   
999.
BACKGROUND & AIMS: Mutations of c-K-ras occur commonly in colonic neoplasms. The aim of this study was to determine how c-K-ras mutations alter the responses to the chemopreventive agent sulindac. METHODS: The parental rat intestinal cell line IEC-18 and c-K-ras-transformed derivatives were treated with sulindac sulfide. Cell cycle distribution was determined by flow-cytometric analysis (fluorescence-activated cell sorter), apoptosis by DNA fragmentation (laddering), flow cytometry, and microscopy, and changes in gene expression by immunoblotting. RESULTS: Sulindac sulfide inhibited cell growth and induced apoptosis in a time- and dose-dependent manner more rapidly in and at lower concentrations in parental cells than ras-transformed cells. Expression of the sulindac sulfide arrested cells in G0/G1, but cells entered apoptosis throughout the cell cycle. Proapoptotic protein Bak was relatively high in untreated parental cells and increased markedly after sulindac sulfide but was low in untreated ras-transformed cells and did not increase after sulindac sulfide. Expression of other Bcl-2 family members was unchanged after sulindac sulfide. However, sulindac sulfide reduced levels of cyclin D1 protein and cyclin E- and cyclin D1- associated kinase activity. CONCLUSIONS: c-K-ras-transformed enterocytes are relatively resistant to sulindac sulfide-induced growth inhibition and apoptosis, which may result from specific reduction of bak expression. (Gastroenterology 1997 Dec;113(6):1892-900)  相似文献   
1000.

Objectives

The present study explored the experiences of people living with advanced heart failure (HF) to determine the extent to which (1) psychosocial resources relevant to HF patients were qualitatively reported, and (2) to determine the extent to which psychosocial resources were correlates of subsequent well-being as assessed by validated quantitative measures.

Background

HF is a serious life-limiting illness that involves impaired heart functionality. Patients commonly face severe physical fatigue and frequently endure disabling depression. Individuals with HF often report the use of social support and religion/spirituality (R/S) as helpful, but little work has systematically linked their reliance on these resources and well-being.

Methods

111 participants completed four open-ended questions to assess aspects of living with HF. Open-ended questions were coded to identify psychosocial resources: positive meaning, gratitude, R/S, social support, and medical resources. Data were collected once and then again 3 months later. Participants also completed measures of well-being, including religious meaning, life meaning, satisfaction with life, depressive symptoms, death anxiety, and health-related quality of life. Bivariate correlations were used to relate psychosocial resources and well-being.

Results

Patients reported many psychosocial resources, particularly positive meaning, R/S, social support, and medical resources. Positive meaning and R/S were inversely linked with depressive symptoms. R/S was also related to less death anxiety, while social support was related to higher anxiety about death three months later.

Conclusions

Findings advance our understanding of the struggles HF patients experience and the roles of psychosocial resources such as meaning and gratitude in alleviating these struggles. Results may help explain how resources like R/S and social support may influence well-being.  相似文献   
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