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121.
Prognostic factors for the success rate of embryo freezing   总被引:5,自引:6,他引:5  
To find some prognostic factors for the outcome of frozen-thawed cycles, we have retrospectively analysed all frozen pre-embryos that were thawed during 1993 and 1994 at two in-vitro fertilization (IVF) units in Sweden. Supernumerary pre-embryos were frozen from 551 oocyte retrievals and these resulted in 660 frozen-thawed cycles which lead to 623 thawed embryo transfers. The outcome of these transfers was 137 clinical pregnancies with a pregnancy rate of 22% per frozen-thawed embryo transfers. Women <40 years of age had a higher birth rate than those > or =40 years, 19 and 5% respectively (P < 0.01). Transfers with two and three pre-embryos resulted in pregnancy rates of 23 and 27%, respectively, compared with 14% for transfer of one embryo. A pregnancy resulting from the initial embryo transfers had a predictive value for results of the subsequent frozen-thawed cycle. Embryo grade and cleavage stage at the time of freezing was important for the survival of the frozen-thawed pre-embryos. The pregnancy rate was not influenced by the cleavage stage, but a tendency toward a lower pregnancy rate was seen for the embryos with lower grading. To conclude, cryopreservation seems to be beneficial in women <40 years of age, who have supernumerary pre-embryos of good quality for freezing and of which at least two can be transferred.   相似文献   
122.
We have previously observed that exogenous oestradiol can delay the intercycle increase in plasma follicle stimulating hormone (FSH). The increase in plasma FSH that follows discontinuation of exogenous oestradiol peaks after 3 days. We have now studied the possibility of using exogenous oestradiol to synchronize the increase in endogenous FSH with the onset of human menopausal gonadotrophin (HMG) treatment in controlled ovarian hyperstimulation (COH). A total of 30 women aged 35.1+/-6.3 years (mean+/-SD) undergoing ovarian stimulation received 2 mg of oestradiol valerate twice daily starting on day 25 of the previous menstrual cycle until the first Tuesday following menses. Ovarian stimulation was initiated 3 days later. On the last day of oestradiol treatment, plasma oestradiol, FSH and luteinizing hormone (LH) (mean+/-SEM) were 566+/-53 (pmol/l), 3.8+/-0.4 (IU/l) and 5.5+/- 0.8 (IU/l) respectively. After 3 days, the FSH and LH (mean+/-SEM) had increased to 6.7+/-0.7 and 6.9+/-0.7 (IU/l) respectively while oestradiol decreased to 251+/-29 (pmol/l). The mean number (+/-SEM) of HMG ampoules used was 25.1+/-2.7 and treatment lasted 11.3+/-0.9 days. Five women became pregnant for a pregnancy rate (ongoing) of 19 (15)%. If all women aged >40 years (six women who did not become pregnant) were excluded from analysis the pregnancy rate (ongoing) was 24 (19%). These results indicate that exogenous oestradiol can safely be used for the synchronization of endogenous and exogenous FSH stimuli in COH. This approach provides the practical advantage of permitting an advanced timing of the onset of COH treatments when gonadotrophin- releasing hormone (GnRH) agonists are not used, which improves treatment convenience for patients and team members alike. Further development of this model may enable control of the onset of natural cycles which may find practical applications for timing assisted reproductive techniques (intrauterine insemination or in-vitro fertilization) in the natural cycle.   相似文献   
123.
The role of post‐mastectomy radiotherapy for pT3N0 breast cancers remains undefined. The purpose of this study was to report institutional outcomes for women with pT3N0 breast cancers treated with and without post‐mastectomy radiotherapy. We collected data from two large tumor registries on pT3N0 breast cancers diagnosed between 1985 and 2014. Kaplan–Meier estimates were used to analyze freedom from local‐regional recurrence (FFLR), relapse free survival, and overall survival. This analysis identified 93 women with pT3N0 breast cancers. Of these, 53 received post‐mastectomy radiotherapy and 40 did not. Median follow‐up was 6.2 years and 5.3 years in the non‐post‐mastectomy radiotherapy and post‐mastectomy radiotherapy cohorts, respectively. Women not undergoing post‐mastectomy radiotherapy were more likely to be diagnosed in the 1980s and 1990s and were less likely to receive systemic therapies than women receiving post‐mastectomy radiotherapy (p < 0.05). There was a trend toward increased FFLR in the women receiving post‐mastectomy radiotherapy (p = 0.15). FFLR in the post‐mastectomy radiotherapy cohort was 98% at both 5 and 10 years. For women not receiving post‐mastectomy radiotherapy, FFLR was 88% at both 5 and 10 years. Women not receiving post‐mastectomy radiotherapy in our study had an isolated local‐regional failure rate of 12% at 10 years, despite receiving inferior systemic treatment by current standards. Local‐regional control after post‐mastectomy radiotherapy for pT3N0 breast cancers was excellent. Further research is needed to define post‐mastectomy radiotherapy indications for this patient population when receiving chemotherapy and endocrine therapy in line with current guidelines.  相似文献   
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OBJECTIVE: Adrenal failure, a treatable condition, can have catastrophic consequences if unrecognized in critically ill ED patients. The authors' objective was to prospectively study adrenal function in a case series of hemodynamically unstable (high-risk) patients from a large, urban ED over a 12-month period. METHODS: In a prospective manner, critically ill adult patients presenting to the ED were enrolled when presenting with a mean arterial blood pressure < or =60 mm Hg requiring vasopressor therapy for more than one hour after receiving fluid resuscitation (central venous pressure of 12-15 mm Hg or a minimum of 40 mL/kg of crystalloid). Patients were excluded if presenting with hemorrhage, trauma, or AIDS, or if steroids were used within the previous six months. An adrenocorticotropic hormone (ACTH) stimulation test was performed and serum cortisol was measured. Treatment for adrenal insufficiency was not instituted. RESULTS: A total of 57 consecutive patients were studied. Of these, eight (14%) had baseline serum cortisol concentrations of <20 microg/dL (<552 nmol/L), which was considered adrenal insufficiency (AI). Three additional patients (5%) had subnormal 60-minute post-ACTH-stimulation cortisol responses (<30 microg/dL) and a delta cortisol < or =9 microg/dL, which is the difference between the baseline and 60-minute levels. This is functional hypoadrenalism (FH). There were no laboratory abnormalities that distinguished patients with AI or FH from those with preserved adrenal function (PAF). Rates of survival to discharge did not differ between the AI group (7 of 8) and PAF patients (21 of 46; p = 0.052). CONCLUSIONS: Adrenal dysfunction is common in high-risk ED patients. Overall, it has a frequency of 19% among a homogeneous population of hemodynamically unstable vasopressor-dependent patients. The effect of physiologic glucocorticoid replacement in this setting remains to be determined.  相似文献   
128.
A unifying feature of the CAG expansion diseases is the formation of intracellular aggregates composed of the mutant polyglutamine-expanded protein. Despite the presence of aggregates in affected patients, the precise relationship between aggregates and disease pathogenesis is unresolved. Results from in vivo and in vitro studies of mutant huntingtin have lead to the hypothesis that nuclear localization of aggregates is critical for the pathology of Huntington's disease (HD). We tested this hypothesis using a 293T cell culture model system that compared the frequency and toxicity of cytoplasmic and nuclear huntingtin aggregates. We first assessed the mode of nuclear transport of N-terminal fragments of huntingtin, and show that the predicted endogenous NLS is not functional, providing data in support of passive nuclear transport. This result suggests that proteolysis is a necessary step for nuclear entry of huntingtin. Additionally, insertion of nuclear import or export sequences into huntingtin fragments containing 548 or 151 amino acids was used to reverse the normal localization of these proteins. Changing the subcellular localization of the fragments did not influence their total aggregate frequency. There were also no significant differences in toxicity associated with the presence of nuclear compared with cytoplasmic aggregates. The findings of nuclear and cytoplasmic aggregates in affected brains, together with these in vitro data, support the nucleus and cytosol as subcellular sites for pathogenesis in HD.   相似文献   
129.
Available data suggest a possible link between abnormal vitamin D level and abnormal glucose homeostasis, two of the most common chronic medical conditions. Both conditions are associated with inflammation, and the exact mechanism for role of either on the other is not well clear. Literature investigating the link between vitamin D and either pre-diabetic states or diabetes is reviewed. Vitamin D deficiency is detrimental to insulin synthesis and secretion in animal and human studies. In humans, it has been shown by majority of observational studies, that vitamin D is positively correlated with insulin sensitivity and its role is mediated both by direct mechanism through the availability of vitamin D receptors in several tissues and indirectly through the changes in calcium levels. Large number of, but not all, variable samples cross sectional human trials have demonstrated an inverse relation between vitamin D status and impaired glucose tolerance, insulin resistance or diabetes. To compliment this conclusively, evidence from intervention studies is critically warranted before we can frankly state that vitamin D plays a role in diabetes prevention or treatment. Absence of both sizable prospective observational trials utilizing 25(OH)D as the main variable and the non-availability of randomized studies specifically designed to assess the effects of vitamin D on pre-diabetes and diabetes states, are the main obstacles to draw solid and conclusive relationships.  相似文献   
130.
A total of 86 renal transplant patients who were transplanted with live related donor (LRD) and live unrelated donor (LURD) kidneys were studied for opportunistic infections. Immune diagnosis of Toxoplasma, Cytomegalovirus (CMV), Herpes-simplex virus type II (HSV-2), Aspergillosis and Tuberculosis was carried out in these patients along with sputum examination, CSF studies and biopsy of lymphnode and other tissues in few cases. A high degree of Toxoplasma, CMV & HSV-2 positivity was seen in transplanted patients. However sensitivity of serological diagnosis of tuberculos was found to be low with standard criteria, which increased significantly when modified criteria were used. It is concluded that regular immunological monitoring should be carried out in transplanted patients so as to reach an early diagnosis and management of opportunistic infections.KEY WORDS: Immune diagnosis, Opportunistic infections, Transplantation  相似文献   
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