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71.
Large doses of antiprogestin typically disrupt menstrual cyclicity. A chronic low-dose regimen of the potent new antiprogestin ZK 137 316, which permits continued menstrual cyclicity but alters gonadal- reproductive tract activity, was established. Rhesus monkeys received vehicle (n = 6) or 0.01 (n = 8), 0.03 (n = 8) or 0.1 (n = 5) mg ZK 137 316/kg body weight daily for five menstrual cycles (C-1 to C-5). Oestradiol, progesterone and gonadotrophin profiles were normal during cycles involving vehicle and 0.01 and 0.03 mg ZK 137 316/kg body weight. In the 0.1 mg/kg group, mid-cycle oestradiol and gonadotrophin surges, and subsequent progesterone production, were absent in C-3 and C-5. Ovarian cyclicity was accompanied by timely menstruation in the vehicle and 0.01 mg/kg groups. By C-3, half the animals in the 0.03 mg/kg group and all animals in the 0.1 mg/kg group were amenorrhoeic. A corpus luteum was noted during the mid-luteal phase of C-5 in the vehicle, 0.01 mg/kg and 0.03 mg/kg groups. Large antral and cystic follicles were evident in the 0.1 mg/kg group. Thus, a daily treatment with 0.01 mg/kg ZK 136317 permitted normal menstrual cyclicity in macaques. While the daily administration of 0.03 mg/kg ZK 136 317 allowed ovarian cyclicity, menstruation was disrupted in some animals. Increasing the dose to 0.1 mg/kg antagonized pituitary function and resulted in anovulation and amenorrhoea. A chronic low-dose regimen of the antiprogestin ZK 137 316, which permits normal ovarian/menstrual cyclicity, has potential as a contraceptive in women.   相似文献   
72.
We studied the antibody response to the fusion (F) and attachment (G) proteins of respiratory syncytial virus and to purified intact virus in the respiratory secretions of 29 infants and children. The goal of the study was to determine whether the immune response to either of the glycoproteins occurred predominantly in the immunoglobulin A (IgA) as opposed to the IgE isotype, which would indicate that one protein subunit would be a better candidate as a potential vaccine. Antibody responses were determined by using an enzyme-linked immunosorbent assay with purified F and G proteins and sucrose gradient-purified intact virus as targets. Infants and children were capable of developing an antibody response in both the IgA and IgE isotypes to each target antigen. The magnitude of the antibody response to the F protein was essentially similar to that to the intact virus, while responses to the G protein were diminished in infants. A slightly more favorable ratio of IgA to IgE responses was observed against the F protein in comparison to the G protein. While neither protein subunit had the ideal characteristics of inducing an IgA response in the absence of an IgE response, the F protein seems to be a better candidate for use as a vaccine, on the basis of better IgA/IgE ratios.  相似文献   
73.
74.
Lung carcinoids occur sporadically and rarely in association with multiple endocrine neoplasia type 1 (MEN1). There are no well defined genetic abnormalities known to occur in these tumors. We studied 11 sporadic lung carcinoids for loss of heterozygosity (LOH) at the locus of the MEN1 gene on chromosome 11q13, and for mutations of the MEN1 gene using dideoxy fingerprinting. Additionally, a lung carcinoid from a MEN1 patient was studied. In four of 11 (36%) sporadic tumors, both copies of the MEN1 gene were inactivated. All four tumors showed the presence of a MEN1 gene mutation and loss of the other allele. Observed mutations included a 1 bp insertion, a 1 bp deletion, a 13 bp deletion and a single nucleotide substitution affecting a donor splice site. Each mutation predicts truncation or potentially complete loss of menin. The remaining seven tumors showed neither the presence of a MEN1 gene mutation nor 11q13 LOH. The tumor from the MEN1 patient showed LOH at chromosome 11q13 and a complex germline MEN1 gene mutation. The data implicate the MEN1 gene in the pathogenesis of sporadic lung carcinoids, representing the first defined genetic alteration in these tumors.   相似文献   
75.
Thyroid tumors following thymus irradiation   总被引:3,自引:0,他引:3  
About 2,650 persons who received X-ray treatment for purported enlarged thymuses in infancy and 4,800 sibling controls have been followed by mail questionnaire for an average of 29 years to observe their incidence of thyroid tumors. The follow-up rate in the latest survey was 88% in both groups. The radiation doses to the thyroid gland ranged from 5 to over 1,000 rad, with 62% receiving less than 50 rad. To date 30 thyroid cancers and 59 benign thyroid adenomas have been detected in the irradiated group, as compared with 1 thyroid cancer and 8 adenomas in the control group. The relative risks in the irradiated group were about 45 for thyroid cancer and 15 for benign thyroid adenomas. The dose-response curve for thyroid cancer was essentially linear, although a linear-quadratic curve could not be ruled out. For thyroid adenomas the risk per rad was somewhat greater at lower doses than at high doses. For both thyroid cancers and adenomas the absolute excess risk per rad was two to three times as great in females as males. Within the limitations imposed by the treatment regimens and the sample size, there was no indication of a "sparing" effect due to dose fractionation for either thyroid cancers or adenomas. There was an excess risk for both malignant and benign thyroid tumors for at least 40 years post irradiation. For thyroid cancer the radiogenic risk appeared to be additive with respect to time, rather than the age-specific natural rates of cancer being multiplied.  相似文献   
76.
In some parts of the United Kingdom (UK), family doctors (or "general practitioners" as they are called in the UK) are routinely called upon by the emergency medical services (EMS) system to attend road accidents. The doctors are volunteers and travel to the scene of the accident in their own cars. Members of one such general practitioner accident service operating in Mid-Anglia complete an accident report form after attending each incident. In 1983, the Mid-Anglia General Practitioner Accident Service (MAGPAS) received 1,715 calls for medical assistance, and in 95% of these a doctor was sent immediately. Of these calls, 57% were passed to the doctor within one minute of the receipt of the call in the MAGPAS control room, and 78% were relayed within two minutes. This rapid call-out, combined with the close proximity of the local doctor to the accident site, resulted in the doctors arriving ahead of the ambulance in 42% of the calls. A total of 54 patients with airway obstruction were treated by the doctors prior to the arrival of the ambulance. Ninety-nine patients required immediate intravenous fluid replacement in the pre-hospital phase of their medical care. This report suggests that general practitioners in rural areas can play a vital role in the early management of trauma patients, especially in the absence of ambulance personnel trained in advanced life support skills.  相似文献   
77.
The purpose of this study was to characterize presenting imaging findings in women younger than 40 diagnosed with invasive breast cancer in the context of pathology and clinical course. Retrospective chart and imaging reviews were performed in patients under 40 diagnosed with breast cancer between July 1, 2004, and December 31, 2013. Patient demographic, imaging, pathology, and clinical data were collected. Overall and recurrence-free survival were estimated using the Kaplan-Meier method. Univariate Cox proportional hazards models were performed to identify factors associated with recurrence-free survival. Our study cohort consisted of 110 patients with invasive mammary carcinoma. One hundred one (91.8%) presented with a palpable mass. The mean size of all lesions on imaging was 3.5 cm ± 2.9 cm. Malignant calcifications were present in 54 (49.1%) cases. Imaging demonstrated multifocal or multicentric disease in 45 (40.9%) cases. Seventy four (67.3%) cancers were high grade. Luminal genomic subtypes were the most common (n = 61, 55.5%). At presentation, 4 (3.6%) patients had bilateral malignancy and 8 (7.3%) patients had distant metastatic disease. Ninety seven (88.2%) underwent neoadjuvant chemotherapy and 67 (60.9%) underwent radiation therapy. Seventy five (68.2%) of the patients underwent mastectomy. The restricted mean time to recurrence was 9.01 years (standard error 3.162 months). ER positivity was associated with compromised recurrence-free survival. The overall survival rate was 0.962 at 10 years. Young patients diagnosed with breast cancer typically present with advanced breast imaging findings and undergo aggressive treatment. Recurrence often occurs >5 years from diagnosis, and ER positive subtypes are at increased risk for recurrence.  相似文献   
78.
Twenty of 26 (77%) consecutive patients undergoing ileogastrostomy, performed by the same surgeon (IGMC) between February 1989 and May 1992, responded to a mailed quality of life survey. Average present weight was reported as 50.9 kg less than a mean preoperative weight of 139.7 kg. Mean time of follow-up was 24.75 months. When comparing perceptions before and after surgery, several quality of life improvements were noted in the areas of vocation, relationships, emotional well-being and physical well-being. Post-surgery, jobs were rated more satisfying, eating habits improved, self-image and self-confidence increased and body disparagement declined. Satisfaction with sexual relations increased, as did frequency. In general, relations with partners, co-workers and friends seemed to improve. Exercise also increased significantly. In contrast, foul flatus, bloating, and bowel movements regularly hampered activities or caused embarassment when in public. Despite these physical side-effects, we observed that a large majority of persons undergoing ileogastrostomy noted significant improvements in quality of life.  相似文献   
79.
下消化道出血221例分析   总被引:4,自引:2,他引:2  
0 引言 下消化道出血是消化科的常见病 ,是指十二指肠空肠移行部 ,屈氏韧带以下的小肠和大肠疾病引起的肠道出血 .有人认为一般不包括痔和肛裂出血 [1 ] .临床最常见为慢性出血 ,但有时出血量大危及生命 ,需要做紧急处理 ,现将我院1992 - 0 1/ 1999- 0 8门诊及病房收治的 2 2 1例下消化道出血进行分析 ,报告如下 :1 临床资料 男 12 0例 ,女 10 1例 ,年龄 14~ 72 (平均 42 )岁 ,病程 16 h~ 10 a.患者分别以脓血便、暗红色血便、鲜血便或果酱色血便为主诉前来就诊 ,其中有休克症状的大出血者6例 .血 Hb<110 g·L- 1 40例 ,<80 g·L- 1…  相似文献   
80.
Objectives. To confirm the observation that has been occasionally reported in the literature that perinatal mortality rate is lower in ethnic Chinese than in ethnic whites, and to assess the reasons for this lower perinatal mortality rate.

Methods. Secondary‐analysis based on published data.

Results. This exercise demonstrates that the perinatal mortality rate was lower in ethnic Chinese than in ethnic whites. The birth weight distribution in ethnic Chinese was more favourable with reduced births at two extremes of the distribution, and the exposure to risk factors for perinatal death by their mothers was also lower.

Conclusion: Perinatal mortality rate is lower in ethnic Chinese than in ethnic whites, and the lower perinatal mortality rate in ethnic Chinese is probably caused by their favourable birth weight distribution and lower exposure to risk factors of perinatal death by their mothers.  相似文献   

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