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71.
The purpose of this special issue of Stem Cell Reviews is to address some of the most difficult ethical debates surrounding the derivation of pluripotent stem cell lines. The possible benefits of stem cells are widely discussed, but the scientific community is particularly aware that research in this area is still at an early, but essential, stage of development. With this research at such an early stage, it is noteworthy that the media, the public, religious leaders, politicians, policy makers, and regulators have had as much interest in stem cell research as for any other area of scientific inquiry. The central issue that has made this area so controversial has been the use of the human embryo for deriving stem cell lines.  相似文献   
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Testicular function after orchiopexy for unilaterally undescended testis.   总被引:4,自引:0,他引:4  
Testicular function was determined in 29 men, 21 to 35 years old, who had undergone orchiopexy for unilaterally undescended testis at four to 12 years of age. Serum testosterone and dialyzable testosterone concentrations of these men were not significantly different from those of a control group of 30 normal men, and their basal serum luteinizing hormone concentrations and serum luteinizing hormone responses to synthetic gonadotropin-releasing hormone were only slightly higher than those of the normal men. The mean sperm density of the patients, however, was only one third of that of the normal men (p less than 0.001). The mean serum follicle stimulating hormone response ro gonadotropin-releasing hormone of the patients was doubled that of the normal men (p less than 0.001). The data indicate that spermatogenesis may be abnormal after orchipexy, and suggest that men with unilaterally undescended testis may have bilateral testicular abnormality.  相似文献   
74.
A slide latex agglutination (SLA) assay was developed for rapid screening for Clostridium perfringens type A enterotoxin (CPE). SLA specifically detected CPE added to buffer or normal feces (sensitivity limit of 1 μg CPE/g feces). Using clinical fecal samples from C. perfringens food poisoning cases, a strong correlation was shown between (1) SLA results and results from other CPE assays and (2) between SLA results and illness status.  相似文献   
75.
Our objective was to correlate p16, p21cip1, p27kip1, and cyclin E protein expression with the degree of dysplasia on ThinPrep Papanicolaou (Pap) smears using a modified immunoperoxidase staining. Smears read as normal, atypical squamous cells of undetermined significance (ASC-US), low-grade squamous intraepithelial lesion (LSIL), or high-grade SIL (HSIL) were identified and tested for high-risk human papillomavirus (HR-HPV). Additional smears were processed for immunoperoxidase for p16, p21cip1, p27kip1, and cyclin E. Thirty-four smears were satisfactory for study. The p16 was positive in all nine HSIL, in four of nine LSIL, and in one of seven ASC-US. The p27kip1 was positive in all nine HSIL, in eight of nine LSIL, and in one of seven ASC-US. The p21cip1 was positive in all nine HSIL, in one of nine LSIL, and in one of seven ASC-US. Cyclin E was positive in seven of nine HSIL and in one of nine LSIL and in none of the ASC-US smears. Normal smears were negative for all the antigens. There was poor correlation of protein expression and HR-HPV infection. We concluded that p16, p21cip1, p27kip1, and cyclin E can be demonstrated on Pap smears and they are expressed differentially in dysplastic cells, with highest expression in HSIL. The p21cip1 and cyclin E showed the greatest correlation with HSIL.  相似文献   
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We retrospectively reviewed 74 fine-needle aspiration (FNA) cases of presumptive non-Hodgkin lymphoma (NHL). All the cases had cytology and core-needle biopsy and 53 cases had concurrent flow cytometric analysis. FNA (cytology and flow cytometry) and core-needle biopsy were evaluated independently. FNA was diagnostic of diffuse large B-cell lymphoma (DLBL) in 25% (13/53) of cases and small B-cell NHL in 15% (8/53) of cases, whereas core-needle biopsy was diagnostic of DLBL in 37% (27/74) of cases and small B-cell NHL in 8% (6/74) of cases. Subclassification of small B-cell NHL was reached in 3/6 cases by core-needle biopsy. Insufficient cases were observed in both FNA (47%; 25/53) and core-needle biopsy (28%; 21/74) groups. With the combination of FNA and core-needle biopsy, diagnostic cases of DLBL increased to 43% (32/74) and insufficient samples were reduced to 16% (12/74). There was no clear advantage in the diagnosis and classification of small B-cell NHL by adding core-needle biopsy to FNA (14%; 10/74). We conclude that core-needle biopsy is a useful adjunct to FNA in the diagnosis of DLBL and shall be encouraged. In small B-cell NHL, core-needle biopsy does not add to the diagnostic ability of FNA. Cases insufficient for diagnosis may be seen in both core-needle biopsy and FNA. A combined approach reduces the number of insufficient cases and is recommended in routine FNA practice.  相似文献   
79.
IntroductionThere are many described technique to performing laparoscopic inguinal hernia repair in children. We describe our outcomes using a percutaneous internal ring suturing technique.MethodsA retrospective review of patients under 18 years old who underwent repair between January 2014 - March 2019 was performed. A percutaneous internal ring suturing technique, involving hydro-dissection of the peritoneum, percutaneous suture passage, and cauterization of the peritoneum in the sac prior to high ligation, was used. p < 0.05 was considered significant during the analysis.Results791 patients were included. The median age at operation was 1.9 years (IQR 0.37, 5.82). The median operative time for a unilateral repair was 21 min (IQR 16, 28), while the median time for a bilateral repair was 30.5 min (IQR 23, 41).In total, 3 patients required conversion to an open procedure (0.4%), 4 (0.6%) experienced post-operative bleeding, 9 (1.2%) developed a wound infection, and iatrogenic ascent of testis occurred in 10 (1.3%) patients. Twenty patients (2.5%) developed a recurrent hernia. All but two were re-repaired laparoscopically.ConclusionsThe use of percutaneous internal ring suturing for laparoscopic repair of inguinal hernias in the pediatric population is safe and effective with a low rate of complications and recurrence.  相似文献   
80.
BackgroundAppendicitis is a common pediatric surgical condition, comprising a large burden of healthcare costs. We aimed to determine if prolonged operative times were associated with increased 30-day complication rates when adjusting for pre-operative risk factors.MethodsPatients <18 years old, diagnosed intraoperatively with acute uncomplicated appendicitis and undergoing laparoscopic appendectomy were identified from the NSQIP-P 2012–2018 databases. The primary outcome, “infectious post-operative complications”, is a composite of sepsis, deep incisional surgical site infections, wound disruptions, superficial, and organ space infections within 30-days of the operation. Secondary outcomes included return to the operating room and unplanned readmissions within 30 days. Logistic regression models were used to assess associations between operative time and each outcome. A Receiver Operating Characteristic (ROC) curve was generated from the predicted probabilities of the multivariate model for infectious post-operative complications to examine operative times.ResultsBetween 2012 and 2018, 27,763 pediatric patients with acute uncomplicated appendicitis underwent a laparoscopic appendectomy. Over half the population was male (61%) with a median operative time of 39 min (IQR 29–52 min). Infectious post-operative complication rate was 2.8% overall and was highest (8%) among patients with operative time ≥ 90 min (Fig. 1). Unplanned readmission occurred in 2.9% of patients, with 0.7% returning to the operating room. Each 30-min increase in operating time was associated with a 24% increase in odds of an infectious post-operative complication (OR=1.24, 95% CI=1.17–1.31) in adjusted models. Operative time thresholds predicted with ROC analysis were most meaningful in younger patients with higher ASA class and pre-operative SIRS/Sepsis/Septic shock. Longer operative times were also associated with higher odds of unplanned readmission (OR=1.11, 95% CI=1.05–1.18) and return to the operating room (OR=1.13, 95% CI=1.02–1.24) in adjusted models.ConclusionThere is a risk-adjusted association between prolonged operative time and the occurrence of infectious post-operative complications. Infectious postoperative complications increase healthcare spending and are currently an area of focus in healthcare value models. Future studies should focus on addressing laparoscopic appendectomy operative times longer than 60 min, with steps such as continuation of antibiotics, shifting roles between attending and resident surgeons, and simulation training.Level of EvidenceLevel III, retrospective comparative study  相似文献   
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