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31.
Fugger EF; Black SH; Keyvanfar K; Schulman JD 《Human reproduction (Oxford, England)》1998,13(9):2367-2370
The world's first deliveries of normal babies after use of flow cytometric
separated human sperm cells (MicroSort) for preconception gender selection
are reported. Offspring were of the desired female gender in 92.9% of the
pregnancies. Most of these pregnancies and births were achieved after
simple intrauterine insemination.
相似文献
32.
Horne G; Jamaludin A; Critchlow JD; Falconer DA; Newman MC; Oghoetuoma J; Pease EH; Lieberman BA 《Human reproduction (Oxford, England)》1998,13(11):3045-3048
Insemination with donor spermatozoa is an integral part of infertility
treatment. For the last 3 years in our unit, intrauterine insemination with
donor spermatozoa (IUID) has been used in preference to vaginal
insemination. In this retrospective study, patients were offered an initial
course of five single intrauterine inseminations with cryopreserved donor
spermatozoa and treatment was then reviewed. A total of 389 patients
received 1465 inseminations. In all, 1119 cycles were monitored using
luteinizing hormone serum analyses and 346 cycles using the urine home test
kits. The clinical pregnancy rate per insemination for the cycles monitored
by the serum assay was 18.0% (202/1119) compared with the urine cycles
(13.7%, 46/346) (P <05). The pregnancy loss rate was not significantly
different (14.4%, 29/202 and 21.7%, 10/46) (serum and urine cycles
respectively). The viable clinical pregnancy rate was significantly higher
(P <03) for the serum cycles than for the cycles using the urinary
monitoring (15.5%, 173/1119 and 10.4%, 36/346 respectively). The cycles
monitored by serum assay had a significantly higher cumulative viable
clinical pregnancy rate (P <0001) of 70.2% after nine inseminations
compared with the urine monitored cycles of 54.8%. The majority of patients
opted for the serum cycles, with a minority self-selecting the urine cycles
mainly for travelling convenience. The explanation for the significant
differences between the viable clinical pregnancy rates per insemination
and the cumulative viable clinical pregnancy rates may be due to the
sensitivity of the urine home test kit or the patients' interpretation of
the result.
相似文献
33.
Recessively inherited L-DOPA-responsive parkinsonism in infancy caused by a point mutation (L205P) in the tyrosine hydroxylase gene 总被引:4,自引:0,他引:4
34.
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36.
J D Seidman R A Yetter J C Papadimitriou 《Archives of pathology & laboratory medicine》1992,116(3):287-290
A variant of uterine leiomyosarcoma containing two morphologic bell populations is described. A smooth-muscle component with a mitotic rate of 13 per 10 high-power fields, and a second population of cells mimicking metastatic small-cell carcinoma were both present. The second population was composed of small angulated epithelioid cells with hyperchromatic nuclei and barely discernible cytoplasm growing in tight rows, often in single file between fascicles of smooth muscle. DNA flow cytometry showed a large tetraploid aneuploid tumor cell population, and further suggested that the epithelioid cells probably represent tetraploid tumor cells in S-phase. Thus, this morphologic variant of leiomyosarcoma, unlike previously described variants of smooth-muscle tumors, is explained by the variable appearance of the neoplastic cells in different phases of the cell cycle. 相似文献
37.
38.
Laura Telford Scott H. Seidman Gary D. Paige 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1996,109(3):407-418
The vestibulo-ocular reflex (VOR) was studied in three squirrel monkeys subjected to rotations with the head either centered over, or displaced eccentrically from, the axis of rotation. This was done for several different head orientations relative to gravity in order to determine how canal-mediated angular (aVOR) and otolithmediated linear (lVOR) components of the VOR are combined to generate eye movement responses in three-dimensional space. The aVOR was stimulated in isolation by rotating the head about the axis of rotation in the upright (UP), right-side down (RD), or nose-up (NU) orientations. Horizontal and vertical aVOR responses were compensatory for head rotation over the frequency range 0.25–4.0 Hz, with mean gains near 0.9. The horizontal aVOR was relatively constant across the frequency range, while vertical aVOR gains increased with increasing stimulation frequency. In the NU orientation, compensatory torsional aVOR responses were of relatively low gain (0.54) compared with horizontal and vertical responses, and gains remained constant over the frequency range. When the head was displaced eccentrically, rotation provided the same angular stimuli but added linear stimulus components, due to the centripetal and tangential accelerations acting on the head. By manipulating the orientation of the head relative to gravity and relative to the axis of rotation, the lVOR response could be combined with, or isolated from, the aVOR response. Eccentric rotation in the UP and RD orientations generated aVOR and lVOR responses which acted in the same head plane. Horizontal aVOR-lVOR interactions were recorded when the head was in the UP orientation and facing toward (nose-in) or away from (nose-out) the rotation axis. Similarly, vertical responses were recorded with the head RD and in the nose-out or nose-in positions. For both horizontal and vertical responses, gains were dependent on both the frequency of stimulation and the directions and relative amplitudes of the angular and linear motion components. When subjects were positioned nose-out, the angular and linear stimuli produced synergistic interactions, with the lVOR driving the eyes in the same direction as the aVOR. Gains increased with increasing frequency, consistent with an addition of broad-band aVOR and high-pass lVOR components. When subjects were nose-in, angular and linear stimuli generated eye movements in opposing directions, and gains declined with increasing frequency, consistent with a subtraction of the lVOR from the aVOR. This response pattern was identical for horizontal and vertical eye movements. aVOR and lVOR interactions were also assessed when the two components acted in orthogonal response planes. By rotating the monkeys into the NU orientation, the aVOR acted primarily in the roll plane, generating torsional ocular responses, while the translational (lVOR) component generated horizontal or vertical ocular responses, depending on whether the head was oriented such that linear accelerations acted along the interaural or dorsoventral axes, respectively. Horizontal and vertical lVOR responses were negligible at 0.25 Hz and increased dramatically with increasing frequency. Comparison of the combined responses (UP and RD orientations) with the isolated aVOR (head-centered) and lVOR (NU orientation) responses, indicates that these VOR components sum in a linear fashion during complex head motion. 相似文献
39.
Striated intramural gallbladder lucencies on US studies: predictors of acute cholecystitis 总被引:1,自引:0,他引:1
Ultrasound scans of 51 consecutive patients with gallbladder wall thickening were reviewed, and specific sonographic features were correlated with surgical and clinical follow-up. Two patterns of thickening were identified as specific indicators of the presence or absence of acute cholecystitis. "Striated" wall thickening, consisting of several alternating, irregular, discontinuous, lucent and echogenic bands, was seen in eight of 13 patients (62%) with acute cholecystitis. This pattern was not encountered in any of the patients who did not have acute cholecystitis. Conversely, "three-layer" thickening, consisting of a single circumferential lucent zone between two relatively uniform echogenic layers, was seen in only one of 13 patients (8%) with acute cholecystitis but in 11 of 38 patients (29%) with other diagnoses. Other abnormalities, including the presence of intramural echogenic foci and wall irregularities, were more frequently seen in patients with acute cholecystitis but were not as helpful. Use of these features may suggest or help exclude a diagnosis of acute cholecystitis in those patients in whom the cause of gallbladder wall thickening is otherwise not apparent. 相似文献
40.
Dominika Seidman Marielle Cavrois Joan F. Hilton Nadia R. Roan Sarah Averbach Margaret Takeda Eric Chang Nandhini Raman Ruth Greenblatt Barbara L. Shacklett Karen Smith-McCune 《Contraception》2021,103(1):44-47
IntroductionEx vivo fusion assays offer an efficient method for studying HIV-1 entry associated with contraceptive use and pregnancy outside of cohort studies of HIV-1 incidence.MethodsWe measured ex vivo HIV-1 fusion to cervical or endometrial immune cells from three groups of women: pregnant, non-pregnant not using hormonal or intrauterine contraception, and using depot medroxyprogesterone acetate (DMPA).Results and conclusionsThere was no excess susceptibility to HIV-1 fusion of cells from pregnant women or DMPA users compared to controls. Although the number of target cells in endometrium was higher in DMPA users compared to controls, HIV-1 fusion was lower.ImplicationsIn ex vivo assays, HIV-1 showed no enhanced fusion to cervical immune cells from pregnant women or DMPA users compared to controls, and lower fusion to endometrial immune cells from DMPA users. This assay is useful for studying hormonal and contraceptive effects on HIV-1 entry into reproductive tract immune cells. 相似文献