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John D Morris Elizabeth T Golub Shruti H Mehta Lisa P Jacobson Stephen J Gange 《AIDS research and therapy》2007,4(1):12-8
Background
Sustained use of antiretroviral therapy has been consistently shown to be one of the primary predictors of long-term effectiveness. Switching and discontinuation reflect patient and provider decisions that may limit future treatment options. In this study, we utilize data reported at semi-annual study visits from three prospective cohort studies, the AIDS Link to IntraVenous Exposure (ALIVE), the Women's Interagency HIV Study (WIHS), and the Multicenter AIDS Cohort Study (MACS), to investigate determinants of HAART modification with a particular focus on reported injection drug use (IDU). 相似文献3.
Anand A. Parthasarathi Shruti A. Japee Roland N. Pittman 《Annals of biomedical engineering》1999,27(3):313-325
A novel modification of conventional video imaging techniques has been developed to determine the velocity of red blood cells (RBCs), which offers compatibility with existing video-based methods for determining blood oxygenation and hemoglobin concentration. Traditional frame-by-frame analysis of video recordings limits the maximum velocity that can be measured for individual cells in vivo to about 2 mm/s. We have extended this range to about 20 mm/s, by electronic shuttering of an intensified charge-coupled device camera to produce multiple images of a single RBC in the same video frame. RBCs were labeled with fluorescein isothiocyanate and the labeled cells (FRBCs) were used as probes to determine RBC velocities in microvessels of the hamster retractor muscle. Velocity was computed as the product of the distance between centroids of two consecutive image positions of a FRBC and the shuttering frequency of the camera intensifier. In vitro calibrations of the system using FRBC and Sephadex beads coated onto a rotating disk yielded an average coefficient of variation of about 6%. Flow conservation studies at bifurcations indicated that the maximum diameter of microvessels below which all the FRBCs in the lumen could be detected was 50 m. The technique was used to estimate mean-FRBC velocity distributions in vessels with diameters ranging from 8 to 50 m. The mean-FRBC velocity profiles were found to be blunter than would be expected for Poiseuille flow. Single FRBCs tracked along an unbranched arteriole exhibited significant temporal variations in velocity. © 1999 Biomedical Engineering Society.
PAC99: 8719Tt, 8717Jj, 4279Pw, 8780Tq, 8719Ff, 4230Va, 0705Pj 相似文献
4.
Shruti Pande Anju Shukla Katta Mohan Girisha 《American journal of medical genetics. Part A》2020,182(10):2226-2229
Trichothiodystrophy, non‐photosensitive type 4 (TTD4), is a rare genetic disorder with an autosomal recessive mode of inheritance. It is characterized by coarse and brittle hair, anomalies of the tissues derived from the neuro‐ectoderm (skin, hair, and nails) and intellectual disability. We herein report two male siblings aged 13 and 16 years with TTD4 and a known homozygous pathogenic variant, c.229del [p.(Arg77Glyfs*76)] in exon 1 of MPLKIP (NM_138701.3). We herein highlight the clinical and molecular findings of the first reported case of TTD4 in probands of Indian ethnicity. 相似文献
5.
In this present series, we studied in detail the cytologic features of five histopathologically verified cases of central giant-cell granuloma (CGCG). All the patients in this series were female, with an age range of 11-60 years. There were three cases with involvement of the lower jaw and two cases had upper jaw involvement. Cytology smears showed dispersed single cells in the background. Nuclei of the individual cells were round to ovoid with fine chromatin and inconspicuous nucleoli. The cytoplasm of these cells was moderate in amount with indistinct cell borders. Many randomly scattered multinucleated giant cells with 10-20 nuclei were present in the background. Combination of clinical features, radiologic pictures, and cytologic features may be helpful for diagnosis of CGCG on fine-needle aspiration cytology. 相似文献
6.
We studied the effect of the nitric oxide (NO) donor, sodium nitroprusside (SNP), on the macroscopic and single-channel currents
due to the 22-pS Ca2+ channel in smooth muscle cells from guinea pig basilar artery. In nystatin-perforated whole-cell recordings, 50 nM SNP decreased
the macroscopic current to 63±12% of control values, without changing the voltage dependence of the current. In cell-attached
patches with BAY-K8644 in the pipette, SNP caused a comparable decrease in single-channel availability (n ·P
o) that was dose dependent over the range of 10 nM to 10 μM SNP. SNP had no effect on single-channel properties, including
slope conductance, voltage dependence of activation, the number of open states, the time constants of the open states, and
the proportion of time spent in each open state. The effect of SNP (50 nM) on single Ca2+ channel openings was reproduced by 8-Br-cGMP (100 μM), which also reduced channel availability without altering channel properties.
The protein kinase inhibitor H-8 (1.5 μM), which exhibits relative specificity for cGMP-dependent protein kinase, completely
inhibited the decrease in single-channel availability expected with SNP. The dose-dependent decrease in Ca2+ channel availability caused by SNP was not altered by prior application of 8-Br-cAMP or forskolin, both of which cause an
increase in Ca2+ channel availability in these cells. Our findings suggest that NO decreases openings of Ca2+ channels in basilar artery smooth muscle cells without altering channel properties, and that it does so by a mechanism likely
to involve cGMP-dependent protein kinase.
Received: 2 July 1996 / Received after revision: 30 September 1996 / Accepted: 2 October 1996 相似文献
7.
The histopathologic features of malignant peripheral nerve sheath tumors (MPNSTs) have been well described. There have been limited studies on the cytologic features of MPNST. In this present study, we have retrospectively reviewed eight histopathology confirmed cases of MPNST over a 5-year period. Detailed cytomorphological analysis of these cases was carried out individually by two observers. On cytology, these cases were diagnosed as benign spindle-cell tumor (two), spindle-cell tumor possibly benign (one), spindle-cell tumor possibly malignant (one), malignant spindle-cell tumor (two), spindle-cell tumor, and neural origin (two). The cardinal cytomorphologic features were loosely cohesive clusters and fascicular arrangement of spindle cells with rounded ends. The kinking of nuclei was not a conspicuous finding. Fibrillary background was noted in two of the cases. Nuclear pleomorphism was ranged from mild to moderate degree. One case exhibited extensive intranuclear pseudoinclusions. Mitotic figures (including atypical forms) were present in almost all the cases. Possibly a constellation of cytologic features such as clusters of short and long fascicles of cells admixed with dissociated spindle cells of round-ended nuclei and prominent nucleoli on myxoid or fibrillary background and frequent mitosis may be helpful in diagnosis of MPNSTs. The cytomorphologic features along with clinical correlation are necessary to increase the diagnostic accuracy of MPNST on aspiration cytology. 相似文献
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Background:The normative data set in authomated perimetry is predominantly of non-Indian origin and hence may not be an accurate basis for visual field analysis in Indian population. This video describes an attempt to create a native normative dataset for automated perimetry, which can then be fed in our machines and be used as the normative database.Purpose:To formulate normative data and to increase domain knowledge of normative values for automated perimetry in Indian population of different age groups.Synopsis:Cross-sectional study conducted on patients receiving outpatient care in a span of 3 years, which included 6586 healthy normal patients (13172 eyes) with vision 6/6 unaided or after refractive correction. The patients were tested with 30-2 SITA FAST threshold algorithm on Humphrey Field Analyzer Model no: 745i. Normative data was calculated on basis of age group ranging from 19-75 years categorized to every decade. Normal values were formulated on basis of perimetry performed on normal patients.Highlights:Our work on creating a native normative dataset may add value as well as increase the accuracy of perimetry analysis in Indian eyes.Online Video Link: https://youtu.be/jqgC2Tn7HIg 相似文献
10.
Purpose:To compare results of a novel “conjunctival frill/smile incision” on surgically induced astigmatism (SIA) and patient discomfort vs conventional trabeculectomy in the initial postoperative period.Methods:Sixty trabeculectomy cases were subjected to either conjunctival frill incision, performed 1.5–2.0 mm from the limbus (study group) or conventional fornix-based conjunctival flap (control group). Corneal astigmatism and suture-induced discomfort were assessed by keratometry and a self-devised patient questionnaire, respectively.Results:Both groups generated a “with the rule” SIA, which was 1.77 vs 2.42 at 1 week and reduced to 1.27 vs 1.8 in the study vs control group, after removal of sutures – both scleral flap releasable and conjunctival at 1 month. Patient discomfort score revealed enhanced comfort in 37% of patients (study group) vs 17% (control group) during the early postoperative period. After 1 month of surgery, good comfort was regained in all cases.Conclusion:This novel suturing technique results in reduced SIA, patient discomfort during the 1st month after trabeculectomy. 相似文献