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Journal of Assisted Reproduction and Genetics - To determine age-adjusted overall success rates for patients undergoing clomiphene citrate only minimal stimulation cycle (mini) in vitro...  相似文献   
54.
Purpose  Sacrococcygeal teratoma (SCT) is the most common congenital neoplasm in neonates. We wished to assess the long-term functional outcome of children undergoing SCT resection. Methods  Records of neonates diagnosed with SCT from two surgeons’ practices, and operated on between 1970 and 2006, were retrospectively reviewed. Patients/parents who consented to participate in the study received a questionnaire, focusing on fecal and urinary continence, constipation and lower extremity weakness. Results  Forty-six patients were identified. Four had died (3 from malignant tumors and 1 motor vehicle accident at 18 years). Of the 42 remaining cases, 39 were benign and 3 were malignant; 2 of the former developed malignant recurrences. Twenty-seven agreed to participate and 14 (52%) completed the questionnaire. Median age of respondents was 16.7 years (3–29), and none of the respondents had a recurrent tumor. Thirteen of the 14 respondents experienced no problem with urinary or fecal incontinence, or lower extremity weakness. The remaining patient had all three problems, but his SCT had involved the spinal cord. Of the ten patients who commented on constipation, one had significant constipation, five occasional constipation, and four no constipation. Conclusions  Functional results after resection of neonatal SCT are excellent, with only a small number of patients reporting problems with fecal or urinary continence, or lower extremity weakness. Constipation is relatively common. This information is important for counseling families with fetal or neonatal SCT.  相似文献   
55.
Although mammalian ovaries contain hundreds of thousands of pre-antral follicles, fewer than 1% of these reach maturity and ovulation. Obtaining immature eggs from the pre-antral follicles of ovarian tissue could increase the possibility of preserving fertility in women undergoing anti-cancer treatment, and in women who wish to delay pregnancy and child raising until they are older. This study reports the birth of 10 healthy mouse pups derived from oocytes obtained from pre-antral follicles after adult ovary tissue cryopreservation and allotransplantation. High in-vitro maturation (55.1%), fertilization (76.3%) and cleavage (98.3%) rates were achieved using these oocytes, and there was no significant difference between the vitrified and control samples except in maturation rate (55.1 versus 72.8%, P < 0.05). After an ultra-rapid vitrification procedure, the warmed tissue fragments were transplanted beneath the kidney capsule of severe combined immunodeficient mice for onward in-vivo culture. Within 10 days of culture, 138 full size oocytes developed from the 456 transplanted pre-antral follicles. In-vivo growth of follicles was followed by in-vitro oocyte maturation, in-vitro fertilization and subsequent embryo transfer, leading to the birth of 10 healthy pups. These results may lead to increasing the possibility of preserving fertility by cryopreservation of ovarian tissue.  相似文献   
56.

Background/Purpose

Retractile testes are testicles that can be brought down into their normal position in the scrotum but then immediately retract upward and out of the scrotum. The purpose of this study is to provide data on the outcome of pediatric patients with retractile testes.

Methods

A retrospective analysis was conducted on prospectively collected data on the outcome of 150 consecutive patients with retractile testis examined and followed up by one pediatric surgeon from April 1982 to April 1999, inclusive.

Results

Age at presentation was 5.2 ± 3.0 years, and follow-up duration was 3.8 ± 3.0 years. The number of retractile testes was 205, right-sided for 58 patients (38.6%), left-sided for 37 (24.6%), and bilateral for 55 (36.7%). Family history of retractile testis was positive in 8 patients (5.3%). Thirty-four patients required surgery (22.7%); indication for surgery was given when retractile testes ascended and became cryptorchid or if testicular size decreased during follow-up. Orchidopexy was required more frequently (P < .001) in patients with an associated hernia (68.8% of cases) than in patients without hernias (9.2%). One patient with spontaneous testicular descent during follow-up had a testicular carcinoma.

Conclusions

These findings suggest that the majority of patients (77.3%) with retractile testes have a spontaneously favorable evolution by 14 years of age and do not require surgical treatment. The authors report the first case of testicular carcinoma in a patient with retractile testis, and this indicates that these patients should be followed up even after testicular descent.  相似文献   
57.
Sera from 15 patients with antineutrophil antibodies against peripheral blood neutrophils were incubated with normal bone marrow, and the reaction with marrow precursors was determined. Serum from controls did not deposit IgG on either peripheral blood or marrow myeloid cells. Serum from patients with moderate immune neutropenia with myeloid hyperplasia deposited IgG on neutrophils, bands and metamyelocytes, but not on earlier precursors. Serum from one patient with severe neutropenia and myeloid hypoplasia deposited IgG on myelocytes and promyelocytes as well as more mature cells. Serum from a patient with antineutrophil antibodies which impaired chemotaxis but who did not have neutropenia deposited IgG only on neutrophils and occasional bands. Immune neutropenia may become increasingly severe as antibodies become directed against earlier precursors.  相似文献   
58.
Human lymphocyte extracts analyzed by high-performance liquid chromatography reveal a major UV-absorbing peak that was shown to be ascorbic acid by spectral, chemical, and enzymatic criteria. Because this peak appeared very prominent in the elution profile of chronic lymphocytic leukemia (CLL) lymphocyte extracts, we measured the ascorbic acid content in lymphocytes from the blood of normal subjects and untreated patients with chronic lymphocytic leukemia. A significantly higher concentration of 111 +/- 15.3 nmol per 10(8) cells (mean +/- SEM) was found in CLL lymphocytes than in normal blood lymphocytes, which contained 42.2 +/- 3.3 nmol per 10(8) cells. Selective enrichment with B and T cells showed that this difference was limited to the chronic lymphocytic leukemia B cell, which had a 5- to 15-fold higher content of ascorbic acid than normal B cells had. In contrast, the ascorbic acid level was similar in normal and CLL T cells. The very high ascorbic acid content provides the chronic lymphocytic leukemia B cell with a reducing substance that could react with oxidants or free radicals.  相似文献   
59.
Expression of murine renin genes in subcutaneous connective tissue.   总被引:2,自引:0,他引:2       下载免费PDF全文
A renin promoter-large tumor antigen (T antigen) fusion gene was constructed to provide a reporter function for renin expression in transgenic mice. These transgenic mice gave rise to tumors in subcutaneous soft tissue, which was attributed to transgene expression at this site. An immunohistochemical analysis of transgenic fetuses from several independent lines revealed scattered T-antigen-containing mesenchymal cells and fibroblasts in the subcutaneous layer of the skin between the panniculus carnosus muscle of the skin and the skeletal muscle of the body wall. This localization is consistent with the location of overt tumorigenesis in adult mice. This pattern was specific for the renin-T antigen fusion gene as no immunohistochemical staining was observed in transgenic fetuses containing a heterologous promoter-T antigen fusion gene. Northern blot analysis of tumor RNA indicated that most of the tumors expressed both T antigen and the endogenous renin gene Ren-1c. In addition, when multiple renin genes were introduced by crossing transgenic mice with nontransgenic DBA/2J mice, which contain another allele of the Ren-1 locus as well as the duplicated locus Ren-2, the resultant tumors expressed the Ren-2 gene. Northern blots were then used to analyze renin expression in the subcutaneous tissue of normal mice. Fully processed renin mRNA was detected in eviscerated 15.5-day postcoitus fetal and newborn carcasses and in newborn skin. Our data indicate that there is a renin-expressing cell population in fetal and newborn subcutaneous tissue.  相似文献   
60.
Carboxy-terminal determinants of intracellular protein degradation   总被引:17,自引:4,他引:17  
Using the amino-terminal domain of lambda repressor as a model system, we show that residues in an unstructured region at the extreme carboxyl terminus of the protein are important for determining its proteolytic susceptibility in Escherichia coli. Nonpolar amino acids are destabilizing when placed at the 5 carboxy-terminal residue positions, whereas charged and polar residues are stabilizing. The stabilizing effect of a single charged residue is greatest when it is at the terminal position and diminishes with increasing distance from the carboxyl terminus. The position of destabilizing sequences with respect to the free carboxyl terminus is important for their effect, but their distance from the folded portion of the protein is not important. Specific degradation of proteins with nonpolar carboxyl termini has been reconstituted in vitro using a partially pure, soluble fraction. This degradation is not ATP-dependent. Moreover, amino-terminal domain variants with nonpolar carboxy-terminal residues are still rapidly degraded in strains that are deficient in proteolysis of abnormal proteins. These data suggest that the degradation of amino-terminal domain variants with nonpolar carboxy-terminal residues involves proteolytic components distinct from those known to be important for the turnover of unfolded proteins in E. coli.  相似文献   
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