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1.
In a prospective, controlled, randomized study where two differentagonists were used, we compared three different long desensitizationprotocols for induction of multiple follicular growth in medicallyassisted conception cycles. In protocol A, 30 patients wereinjected with buserelin twice a day for 15 days prior to ovarianstimulation until human chorionic gonadotrophin (HCG) administration.In protocol B, 30 patients were injected with a single doseof long acting Triptorelin (3.75mg) 15 days before the ovarianstimulation onset. In protocol C, 30 patients were injectedwith the long acting Triptorelin 4 weeks before ovarian stimulationfollowed by daily administration of 0.1 mg of the same agonistuntil HCG injection. There was no difference in the ovarianresponse to exogenous gonadotrophin stimulation, except forthe presence of premature luteinization in two patients in groupB. A significantly higher number of mature oocytes was collectedfrom patients with protocol A; however, the fertilization andcleavage rate demonstrated no significant difference among thethree groups of patients. The ongoing pregnancy rate and theimplanation rate per treatment cycle were very similar in thethree study groups. When the convenience, cost and side-effectsfor the patient are being considered, protocol B should be selectedas the first choice when the agonist is utilized for the purposeof inducing pituitary desensitization before and during ovarianstimulation.  相似文献   
2.
Human oocyte development was evaluated after a reduced timeexposure to spermatozoa in vitro. A total of 119 patients wereassigned to two study groups in a randomized prospective studyin which each patient‘s oocytes were exposed to spermatozoafor either 1 h (group 1 – 58 patients) or the standard16 h incubation period (group 2 – 61 patients). The fertilizationrate obtained in group 1 was higher than in group 2 (285/393,73%, and 272/410, 66% respectively), suggesting that the spermatozoa-oocyteinteraction occurs within 1 h. This was confirmed in a studyin vitro using fluorescently labelled spermatozoa and normaloocyte-cumulus complexes. Spermatozoa enter the cumulus complexwithin 15 min, traverse the cumulus layer within 3 h, and firstappear in the oocyte cortex at 4 h post-insemination. The incidenceof polyspermy was higher in oocytes exposed to spermatozoa for16 h (3%) than for 1 h (1%). There was no difference in thecleavage rate or morphological characteristics of embryos fromboth study groups. However, when evaluating the timing of embryodevelopment, group 1 generated a significantly higher percentageof four to five cell embryos when compared to group 2 (55 versus39%; P < 0.001), documented at 40 h post-insemination. Theimplantation and pregnancy rates for group 1 were 11 and 28%,while the corresponding rates for group 2 were 8 and 15%. Thissuggests that a reduced exposure of oocyte to spermatozoa favoursembryo viability, possibly due to a decrease in potential damagefrom sperm metabolic waste products.  相似文献   
3.
The response of murine, bovine and human oocytes to pure recombinant preparations of human follicle stimulating hormone (rFSH) and luteinizing hormone (rLH) for meiotic maturation and subsequent developmental competence in vitro were examined in the present experiments. Maturation of immature bovine oocytes to the metaphase II stage was significantly increased by the addition of 1 IU/ml of rFSH in combination with either 1 IU/ml rLH or 10 IU/ml rLH. Similarly, embryonic development to the blastocyst stage was improved in bovine oocytes treated with a 1:10 combination of rFSH:rLH. However, no significant difference was observed in the number of inner cell mass or trophectoderm cells of the resulting blastocysts. Although the increased maturation to metaphase II was not significant, human embryonic developmental competence was improved by maturing oocytes in the presence of a 1:10 ratio of rFSH:rLH as only those oocytes exposed to a 1:10 ratio of rFSH: rLH during maturation showed normal cleavage patterns beyond day 2. In addition, 1 IU/ml rFSH and 1 IU/ml rLH increased the expression of oocyte proteins in human oocytes. The inclusion of recombinant gonadotrophins, either singly or in combination, had no significant effect on the maturation, fertilization or embryonic development of in-vitro matured mouse oocytes. These data provide support for the responsiveness of human and bovine oocytes to gonadotrophins in vitro and the need to consider variations in the relative concentrations for optimization of oocyte developmental competence.  相似文献   
4.
Purpose: Preimplantation genetic diagnosis of aneuploidy was performed on the embryos yielded by 70 poor-prognosis patients, with the aim of transferring those with a normal chromosomal complement, thus possibly increasing the chances of pregnancy. Methods: Multicolor fluorescence in situ hybridization (FISH) was applied for the simultaneous detection of chromosomes X, Y, 13, 16, 18, and 21. Inclusion criteria were (1) a maternal age of 36 years or older (n = 33), (2) three or more previous in vitro fertilization cycles (n = 20), and (3) an altered karyotype (n = 17). Results: A total of 412 embryos underwent FISH, resulting in 234 (57%) that were chromosomally abnormal. Euploid embryos were available for transfer in 59 patients, generating 19 pregnancies (32%), with an implantation rate of 19.9%. Conclusions: High rates of chromosomally abnormal embryos in poor-prognosis patients can determine repeated in vitro fertilization failures when embryo selection is performed on the basis of morphological criteria alone. Hence, the FISH analysis could represent the prevailing approach for the identification of embryos possessing full potential for developing to term.  相似文献   
5.
Purpose: To investigate the long-term (10 years) effects of augmented bilateral lateral rectus (aBLR) recession in patients affected by divergence excess intermittent exotropia (deIXT). Methods: Data of 58 patients affected by deIXT who underwent aBLR muscle recession were retrospectively analyzed. All patients were treated with 8.0 to 9.5 mm (mean 8.6 ± 0.5 mm) recession of BLR.Results: Our result showed a significant decreasing of both distance and near residual deviation during follow-up. The percentage of patients with successful surgical outcome (defined as a residual deviation ranging from 10pd intermittent exotropia to 5pd esotropia) increased during follow-up (from 51.7% to 81% at last follow-up). Stereopsis increased in 39.7% of patients at last follow-up. Moreover, there was a significant correlation between age at surgery and short/mid-term residual deviation. Conclusions: Our long-term results suggest that aBLR recession surgery is a very effective approach in patients affected by deIXT.  相似文献   
6.

Objective

To identify the factors associated with recovering autonomy in activities of daily living (ADL) in patients who have had a hip fracture.

Design

A prospective cohort study.

Setting

The orthopedic and orthogeriatric departments of 2 regional hospitals.

Participants

Patients (N=742) aged ≥65 years with a diagnosis of fragility hip fracture.

Main Outcome Measures

The level of autonomy at 4 months was assessed using the ADL scale.

Results

The median score on the ADL scale at 4 months was 3 (interquartile range, 5). Half of the population was unable to recover their prefracture autonomy levels. The following were found to be risk factors: increasing age (B=.02, P<.001); an elevated number of comorbidities (B=.044, P=.005); a lower level of prefracture autonomy (B=.087, P<.001); more frequent use of an antidecubitus mattress (B=.211, P<.001); an increased number of days with disorientation (B=.002, P=.012); failure to recover deambulation (B=.199, P<.001); an increased number of days with diapers (B=.003, P<.001), with a urinary catheter (B=.03, P<.001), and with bed rails (B=.001, P=.014); and a nonintensive care pathway (B=.199, P=.014).

Conclusions

Recovery of deambulation, treatment of disorientation and management of incontinence are modifiable factors significantly associated with the functional recovery of autonomy.  相似文献   
7.
International Journal of Legal Medicine - A correct assessment on the position, path, and direction of fracture lines is crucial when the sequence of different injuries on the skull has to be...  相似文献   
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The intent of this study was to evaluate a recent randomized clinical trial evaluating the effect of preimplantation genetic screening (PGS) that reports a negative effect on pregnancy outcome. This article reviews appropriate PGS techniques and how they differ from the trial in question. A closer look at the clinical trial in question reveals significant lack of expertise in biopsy, cell fixation, genetic analysis, and patient selection. At most, this trial demonstrates that in inexperienced hands, PGS can be detrimental. No other conclusions concerning the effect of PGS on pregnancy results can be drawn from the trial.  相似文献   
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