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1.
2.
Y chromosome deletions in azoospermic and severely oligozoospermic men undergoing intracytoplasmic sperm injection after testicular sperm extraction 总被引:11,自引:16,他引:11
Silber SJ; Alagappan R; Brown LG; Page DC 《Human reproduction (Oxford, England)》1998,13(12):3332-3337
Y chromosome deletions encompassing the AZFc region have been reported in
13% of azoospermic men and 7% of severely oligozoospermic men. We examined
the impact of these Y deletions on the severity of testicular defects in 51
azoospermic men undergoing intracytoplasmic sperm injection (ICSI) after
testicular sperm extraction (TESE) and 30 men with severe oligozoospermia
undergoing ICSI after ejaculation of spermatozoa. In addition, five
azoospermic patients shown previously to have Y chromosome deletions
underwent histological evaluation of their previously obtained testis
biopsy specimens. A further 27 azoospermic men underwent TESE-ICSI, but not
Y chromosome DNA testing. Ten of 51 azoospermic men (20%) who underwent
TESE-ICSI and Y-DNA testing were found to be deleted for portions of the Y
chromosome AZFc region. Of these 10, five had spermatozoa retrievable from
the testis, and in two cases the wives became pregnant. Of the 41
azoospermic men with no Y chromosome deletion, 22 (54%) had spermatozoa
retrievable from the testis, and in 12 cases (29%) the wives became
pregnant. Four of 30 (13%) severely oligozoospermic patients were found to
be deleted for AZFc and in three (75%) of these pregnancy was achieved. The
other 26 severely oligozoospermic couples who had no AZFc deletions
underwent ICSI, and 12 (46%) have an ongoing or delivered pregnancy. The
embryo implantation rate was not significantly different for azoospermic
(22%), oligozoospermic (16%), Y-deleted (14%) or Y-intact (18%) men. Of the
total of 19 infertile men who had Y chromosome deletions, 14 had deletions
within Y chromosome intervals 6D-6F, in the AZFc region. Twelve of those 14
had some spermatozoa (however few in number) in the ejaculate or testis.
Five of the Y-deleted men had deletions that extended more proximally on
the Y chromosome, and in none of these could any spermatozoa be observed in
either ejaculate or testis. These results support the concept that, in
azoospermic or oligozoospermic men with Y chromosome deletions limited to
intervals 6D-6F (AZFc), there are generally very small numbers of
testicular or ejaculated spermatozoa. Larger Y deletions, including and
extending beyond the AZFc region and encompassing more Y genes, tend to be
associated with a total absence of testicular spermatozoa. In those cases
where spermatozoa were retrieved, the presence of Y deletions had no
obvious impact on fertilization or pregnancy rate.
相似文献
3.
Inamdar D Alagappan M Shyam L Devadoss S Devadoss A 《Journal of orthopaedic surgery (Hong Kong)》2005,13(2):186-189
Interlocking nailing is a widely accepted and performed treatment for tibial shaft fractures. The addition of percutaneously placed transfixation screws increases the stabilisation provided by intramedullary nailing; however, the technical complexity associated with the procedure has introduced new potential complications. We report a pseudoaneurysm of the anterior tibial artery caused by a proximal interlocking screw after intramedullary nailing surgery to repair a tibial shaft fracture. The patient experienced complete relief of symptoms following removal of the nail and the screws, excision of the proximal fibula, resection of the pseudoaneurysm, and ligation of the anterior tibial artery. We recommend the oblique placement of the proximal interlocking screws to prevent this rare complication. 相似文献
4.
Prevalence of intestinal parasitic infestation in HIV/AIDS patients with diarrhea in Madurai City, South India 总被引:1,自引:0,他引:1
Ramakrishnan K Shenbagarathai R Uma A Kavitha K Rajendran R Thirumalaikolundusubramanian P 《Japanese journal of infectious diseases》2007,60(4):209-210
The prevalence and pattern of parasitic infestation among 80 HIV/AIDS patients with diarrhea in Madurai, south India, was studied by microscopy. Eighty HIV-negative patients were used as controls. Intestinal parasites were detected in 31 HIV/AIDS patients (38.7%) and in 14 (17.5%) HIV-negative patients, a difference that was statistically significant (P < 0.05). In HIV/AIDS patients with diarrhea, protozoa accounted for the majority of diarrhea cases (Entamoeba spp. 37.5%, Cryptosporidium parvum 28.7%). It is therefore suggested that enteric infections are more common in HIV-infected patients than in HIV-negative persons in south India, and this may be due to differences in immunological profile, susceptibility as well as factors related to sanitation and the environment. 相似文献
5.
Vijayanand Alagappan Juergen Nistler Elfar Adalsteinsson Kawin Setsompop Ulrich Fontius Adam Zelinski Markus Vester Graham C Wiggins Franz Hebrank Wolfgang Renz Franz Schmitt Lawrence L Wald 《Magnetic resonance in medicine》2007,57(6):1148-1158
An eight-rung, 3T degenerate birdcage coil (DBC) was constructed and evaluated for accelerated parallel excitation of the head with eight independent excitation channels. Two mode configurations were tested. In the first, each of the eight loops formed by the birdcage was individually excited, producing an excitation pattern similar to a loop coil array. In the second configuration a Butler matrix transformed this "loop coil" basis set into a basis set representing the orthogonal modes of the birdcage coil. In this case the rung currents vary sinusoidally around the coil and only four of the eight modes have significant excitation capability (the other four produce anticircularly polarized (ACP) fields). The lowest useful mode produces the familiar uniform B(1) field pattern, and the higher-order modes produce center magnitude nulls and azimuthal phase variations. The measured magnitude and phase excitation profiles of the individual modes were used to generate one-, four-, six-, and eightfold-accelerated spatially tailored RF excitations with 2D and 3D k-space excitation trajectories. Transmit accelerations of up to six-fold were possible with acceptable levels of spatial artifact. The orthogonal basis set provided by the Butler matrix was found to be advantageous when an orthogonal subset of these modes was used to mitigate B(1) transmit inhomogeneities using parallel excitation. 相似文献
6.
K. Alagappan J. McGowan D. DeClaro D. Ng R. A. Silverman 《International journal of emergency medicine》2008,1(2):123-126
Introduction
Public health initiatives to immunize children and adults have effectively reduced the number of tetanus cases in the USA. However, in the Third National Health and Nutrition Examination Survey (NHANES III), immigrants from Mexico had a 67% nonprotective anti-tetanus antibody (ATA) level. Less work has been conducted among other vulnerable populations such as human immunodeficiency virus (HIV)-infected patients. The objective of this study was to measure ATA levels among the HIV immigrant population compared with US-born HIV-infected patients.Methods
A convenience sample of 158 HIV-infected individuals was recruited to determine the levels of ATA. A nonprotective level of ATA was defined as below 0.15 IU/ml.Results
Among the HIV-infected patients, 72% (114/158) were born in the USA. A total of 17% (27/158) lacked protective levels of ATA. A total of 6.1% (7/114) of those born in the USA lacked protection, compared to 45% (20/44) born outside the USA (p?0.0001).Conclusion
The results illustrate that the country of birth is an important predictor of ATA protection, even among HIV-infected patients. 相似文献7.
Kumar Alagappan MD Maurice Steinberg MD Noel Mancherje MD Simcha Pollack PhD Kenneth Carpentel PhD 《Academic emergency medicine》1996,3(12):1131-1135
Objective: To prospectively evaluate psychological stress reactions among residents in an emergency medicine (EM) rotation during a 4-week period.
Methods: Pre- and postrotation psychological distress levels were assessed over a 4-week EM rotation. Subjects were evaluated by several psychometric measures. These included the assessment of anxiety, depressive, and other psychological symptoms by the Brief Symptom Inventory (BSI), and the occurrence of traumatic anxiety via the Dissociative Experience Scale (DES). Also assessed were the Impact of Events Scale and the Holmes Social Readjustment Ratings Scale (Holmes), a baseline life-change measure. Demographic data were obtained. The study occurred in a university-affiliated teaching hospital ED. The 45 EM residents and 27 non-EM residents were analyzed as a group, followed by subgroup analysis comparing EM vs non-EM residents.
Results: An increase in psychological distress over the 4-week rotation was found in the non-EM group, but not in the EM group. For the non-EM residents, all 10 BSI scales worsened and 3 of 4 DES scales worsened (p = 0.002), indicative of increased psychological distress. In contrast, analysis of the 45 EM residents showed improvement in 8 of 10 BSI scales and 3 of 4 DES scales (p = 0.057).
Conclusion: A significant increase in psychologic distress was found among the non-EM residents during an EM rotation. The EM residents showed a trend for a decrease in psychological distress over the same 4-week period. 相似文献
Methods: Pre- and postrotation psychological distress levels were assessed over a 4-week EM rotation. Subjects were evaluated by several psychometric measures. These included the assessment of anxiety, depressive, and other psychological symptoms by the Brief Symptom Inventory (BSI), and the occurrence of traumatic anxiety via the Dissociative Experience Scale (DES). Also assessed were the Impact of Events Scale and the Holmes Social Readjustment Ratings Scale (Holmes), a baseline life-change measure. Demographic data were obtained. The study occurred in a university-affiliated teaching hospital ED. The 45 EM residents and 27 non-EM residents were analyzed as a group, followed by subgroup analysis comparing EM vs non-EM residents.
Results: An increase in psychological distress over the 4-week rotation was found in the non-EM group, but not in the EM group. For the non-EM residents, all 10 BSI scales worsened and 3 of 4 DES scales worsened (p = 0.002), indicative of increased psychological distress. In contrast, analysis of the 45 EM residents showed improvement in 8 of 10 BSI scales and 3 of 4 DES scales (p = 0.057).
Conclusion: A significant increase in psychologic distress was found among the non-EM residents during an EM rotation. The EM residents showed a trend for a decrease in psychological distress over the same 4-week period. 相似文献
8.
Hancu I Lee SK Dixon WT Sacolick L Becerra R Zhang Z McKinnon G Alagappan V 《Journal of magnetic resonance imaging : JMRI》2012,36(4):865-872
Purpose:
To develop a simple correction approach to mitigate shading in 3 Tesla (T) breast MRI.Materials and Methods:
A slightly modified breast receive (Rx) array, which we termed field shaping array (FSA), was shown to mitigate breast shading at 3T. In this FSA, one Rx element was selectively unblocked and tuned off the Larmor frequency during the transmit (Tx) phase. The current flowing in this element during Tx created a secondary transmit field; the vector addition of this field and the one created directly by the body coil resulted in a more uniform excitation profile over the entire breast area. The receive Rx element was returned to its intended tuning during the Rx phase, ensuring unperturbed signal reception.Results:
Using the FSA, improved Tx field uniformity, better fat suppression, increased image homogeneity and reduced power deposition was seen in all volunteers studied.Conclusion:
A simple modification of a standard breast Rx array, converting it to a field shaping array, was shown to mitigate breast shading in all volunteers studied. J. Magn. Reson. Imaging 2012;36:865–872. © 2012 Wiley Periodicals, Inc. 相似文献9.
10.
Kawin Setsompop Lawrence L Wald Vijayanand Alagappan Borjan Gagoski Franz Hebrank Ulrich Fontius Franz Schmitt Elfar Adalsteinsson 《Magnetic resonance in medicine》2006,56(5):1163-1171
Spatially selective RF waveforms were designed and demonstrated for parallel excitation with a dedicated eight-coil transmit array on a modified 3T human MRI scanner. Measured excitation profiles of individual coils in the array were used in a low-flip-angle pulse design to achieve desired spatial target profiles with two- (2D) and three-dimensional (3D) k-space excitation with simultaneous transmission of RF on eight channels. The 2D pulse excited a high-resolution spatial pattern in-plane, while the 3D trajectory produced high-quality slice selection with a uniform in-plane excitation despite the highly nonuniform individual spatial profiles of the coil array. The multichannel parallel RF excitation was used to accelerate the 2D excitation by factors of 2-8, and experimental results were in excellent agreement with simulations based on the measured coil maps. Parallel RF transmission may become critical for robust and routine human studies at very high field strengths where B(1) inhomogeneity is commonly severe. 相似文献