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21.
OBJECTIVE: To determine if conventional sperm parameters, specific characteristics of sperm motion determined by computer-aided semen analysis (CASA), sperm penetration assay (SPA), and/or spontaneous acrosome reaction assay could best predict fertility outcome after intrauterine insemination (IUI) from frozen donor sperm. DESIGN: A retrospective analysis of 2,245 cycles of therapeutic donor IUIs were initially studied; 1,147 cycles that met selection criteria were used in this report. SETTING: A university-based assisted reproductive technology center. PATIENTS, PARTICIPANTS: All IUIs were performed on women with documented patency of at least one fallopian tube, ovulatory cycles, and who did not receive human menopausal gonadotropins. Sperm donors had to be used for at least four different recipients (mean of 15) and at least 14 different cycles of insemination (mean of 41). INTERVENTIONS: None. MAIN OUTCOME MEASURE: Pregnancy. RESULTS: Statistical comparisons were made between donors of different relative fertility by using the Mann-Whitney test, Spearman's rank correlation, and multiple regression analysis. These analyses demonstrated that the most significant predictors of the fertility of frozen-thawed donor sperm were curvilinear velocity, straight line velocity, and the total number of motile sperm inseminated. The number of sperm with spontaneous acrosome reactions negatively correlated with fertility outcome, and SPA provided no predictive value. CONCLUSIONS: Our study supports the hypothesis that the study of sperm motion characteristics using CASA after thawing and washing of cryopreserved sperm is a better predictor of fertile outcome after IUI than analysis of fresh semen.  相似文献   
22.
Forty normal one-month-old infants were randomly assigned to a breast-like nipple (Healthflow) bottlefeeding or a standard nipple (Evenflo) bottlefeeding group for one 20-minute feeding by the infants' mothers. The data suggested that the mothers' bottlefeeding behaviors did not differ, but the infants who fed on the breast-like nipples spent less time asleep, more time awake and active and less time fussing and crying. In addition, the vagal tone of that group decreased more during bottlefeeding and increased more after the feeding, suggesting that the breast-like nipple bottlefeedings were more similar to breastfeedings (vagal tone being lower during breastfeeding and higher after breastfeeding versus bottlefeeding). Because many women who breastfeed return to work, bottlefeeding that more closely approximate breastfeedings may ease this transition and may provide more effective supplemental feedings for the breastfed infants.  相似文献   
23.
The etiology of idiopathic scoliosis remains unknown. The condition results in a characteristic deformity of the spine and surrounding tissues. Both Types I and II collagen are important constituents of the affected tissues, and thus defective collagens are reasonable candidates for the primary abnormality in adolescent idiopathic scoliosis (AIS). Direct analyses of the amount and solubility of collagen have revealed differences between normal individuals and those with AIS. However, these changes may be secondary to the mechanical effects of the spinal deformity. Segregation analysis was done of genetic markers linked to the structural genes encoding Types I and II collagen to test these candidate loci in four pedigrees with dominantly inherited AIS. In one pedigree, markers linked to both of the Type I collagen loci (COL1A1 and COL1A2) were found to be inherited independently of the abnormal phenotype. Two pedigrees were discordant at one of the Type I loci. The condition also segregated independently of the locus for Type II collagen (COL2A1) in three pedigrees. This is evidence against idiopathic scoliosis generally being caused by mutations in the Types I and II collagen genes.  相似文献   
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Introduction There have been many surgical techniques described for the treatment of pilonidal sinuses. Recurrent disease causes significant morbidity particularly with time from work. Aim To assess the rhomboid flap's role in promoting one‐stage primary healing in pilonidal disease and to evaluate the morbidity and recurrence. Methods Fifty‐three patients were prospectively recruited of which 27 had previous multiple abscess formation requiring surgical drainage from their pilonidal disease, although none had acute disease at the time of surgery. By using the transposition flap, we were able to obliterate the natal cleft and therefore the rolling action of the buttocks between the cleft in these patients and thereby remove one of the factors involved in pilonidal disease. Hospital stay, healing time, wound infection, wound breakdown and recurrence were noted. Results There were 47 males and 6 females with a median age of 28 years (range 16–64 years). Median follow‐up was 24 months (range 3–36 months). Post‐operative morbidity involved superficial wound infection in 7 (13%) which settled with out‐patient dressings. There were four recurrences (7%), two occurred between the flap and the anal canal, and the other two in the flap margin needing intervention. All the patients healed their wounds and the median healing time was 14 days. Conclusion As this condition affects a predominantly young population causing significant time off from work, we feel that the Rhomboid Flap is useful for difficult cases in that it allows early return to full activity and does not necessitate prolonged postoperative care.  相似文献   
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27.
In this study, 50 patients were randomly assigned to treatment with 5-fluorouracil (FUra) or FUra plus high-dose continuous-infusion folinic acid. Five of 27 evaluable patients in the FUra group versus 10 of 21 patients in the FUra plus folinic acid arm of the study had objective partial remissions, P = 0.02. Time to progression was 3.9 months for FUra and 8.0 months for FUra and folinic acid, P = 0.006; however, median survivals (11.9 versus 14.5 months) were not different in this crossover study. Toxicity in both treatment arms was mild, although patients receiving FUra plus folinic acid experienced significantly more stomatitis than patients treated with FUra alone. This study suggests that high-dose, continuous-infusion folinic acid, which produces a steady-state level of biologically active folates of 10 microM, significantly increases the therapeutic activity of FUra.  相似文献   
28.
We have given an overview of the management of the acute myocardial infarction patient utilizing the aggressive reperfusion techniques available today. Anatomic reperfusion rates have been over 95% with the combined methods described. The remaining problems technically are those of earlier reperfusion, methods to enhance myocardial recovery after ischemia, and prevention of restenosis or reocclusion. The use of laser methodology, coronary sinus retroperfusion, partial left heart bypass, and other innovative strategies may improve these results. The introduction of tissue plasminogen activator will affect our approach and will profoundly alter society's expectations of therapeutic success. Still, patients will die from acute myocardial infarction and its complications. The search for a prevention must, therefore, not be overshadowed by our current enthusiasm for reperfusion techniques. Hopefully, our current approach will become a historical footnote as breakthroughs in preventive strategies occur.  相似文献   
29.
Deferred treatment for prostate cancer   总被引:2,自引:0,他引:2  
The clinical outcome of 278 prostate cancer patients managed by a deferred treatment policy was analysed retrospectively. Following TURP or biopsy, all patients were asymptomatic and deemed suitable for management by a deferred treatment policy, i.e. hormone therapy or other forms of treatment were only initiated if and when symptomatic progression occurred. The overall 5-year survival rate was 30%; 18% of patients died from other causes without needing treatment for their prostate cancer; 11% were alive and untreated after 5 years' follow-up; 17% died from prostate cancer without further treatment. Poor tumour grade, anaemia, metastatic disease, a short history, presentation with retention, and a raised serum creatinine at presentation were associated with a poor prognosis.  相似文献   
30.
Young adult rats were unilaterally bulbectomized and tritiated thymidine ([3H]TdR) was injected at variable times following surgery to determine the effect of bulbectomy on the rates of cell proliferation and cell death in the olfactory epithelium. Removal of the olfactory bulb elicits a two- to fourfold increase in the proliferation rate of ipsilateral olfactory epithelial cells 7-50 days following surgery. On the contralateral side, there was a temporary twofold increase in the proliferation rate during the second week after surgery, but this returned to control values at 3 weeks. This temporary increase was in parallel with the response on the ipsilateral side so that the ratio between operated and unoperated sides remained at two. Cell death in olfactory epithelium is also up-regulated following bulbectomy. Death of cells can occur as early as 1 day following incorporation of [3H]TdR, i.e., well before the sensory neurons become mature. This means there is an over-production of sensory cells, and they die at all stages of their life cycle. The number of cells dying is greater after bulbectomy, indicating that the overproduction of olfactory cells is more pronounced after surgery.  相似文献   
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