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81.
In the current study, we compared the in vitro potency of a unique form of gonadotropin-releasing hormone (GnRH) present in the brain of the guinea pig (gpGnRH) with that of mammalian GnRH (mGnRH) as well as their binding affinities to the GnRH receptor. In gpGnRH, the highly conserved histidine in position 2 (His2) and leucine in position 7 (Leu7) are substituted by tyrosine and valine, respectively. In vivo, gpGnRH was shown to be less potent than mGnRH, possibly in part because of higher susceptibility to enzymatic degradation. In the present in vitro experiments, we observed that gpGnRH was less potent than mGnRH in stimulating the release of luteinizing hormone (LH) from primary pituitary cell cultures of the rat, and at lower concentrations from primary pituitary cell culture of the guinea pig, too. These results were confirmed by radioligand-binding studies. It is concluded that the lower biological activity of gpGnRH in both rat and guinea pig may be explained by the difference in binding to the target cells, although additional factors such as proteolytic degradation may also contribute to the observed phenomenon.  相似文献   
82.

Objective

As its central basis for research, the Competence Network for HIV/AIDS (KompNet) established a nationwide cohort study on HIV-positive patients being in medical care in Germany. In this paper, we describe the epidemiological composition, and clinical as well as treatment characteristics of the KompNet cohort over time.

Methods

The KompNet cohort is an open, retrospective and prospective, multi-center, disease-specific and nationwide cohort study that started gathering data in June 2004. Semiannually, follow up visits of the patients are documented, covering a wide range of clinical and sociodemographic data. At enrolment and three years afterwards, an EDTA-sample is taken; a serum-sample is taken at every follow up.

Results

As of 20.10.2008, a total of 15,541 patients were enrolled by 44 documenting sites. In September 2007, the cohort size was reduced to ten outpatient clinics and fifteen private practitioners, covering a total of 9,410 patients. The documentation of these patients comprised 24,117 years of follow up-time since enrolment (mean: 2.6 years), 62,862 person years inclusive data documented retrospectively on course of HIV-infection and antiretroviral therapy (ART, mean: 6.7 years). Due to the short period of recruitment till now, rates of death (0.3%-0.8%) and losses to follow up (1.1%-5.5%) were low.84.9% of patients were men. Main risk of transmission was sex between men (MSM: 62.9%). Mean age was 45 years. About two third of patients were classified as CDC-stage B or C. Therapy regimens of currently treated patients complied with recent guidelines. Trends of mean CD4 cell count/μl regarding the initial therapy and concerning the population under treatment reflected the developments and the changing standards of antiretroviral therapy over time.

Conclusion

The KompNet cohort covers about a quarter of all patients estimated as being under treatment in Germany. Its composition can be accounted approximately representative for the situation of clinical care and treatment in the scope of HIV/AIDS in Germany. Therefore, it is an important instrument for measuring the course of HIV/AIDS, the reality of use of antiretroviral therapy and its clinical and psychosocial outcomes in Germany.  相似文献   
83.
84.

Introduction

Endoscopic retrograde cholangiopancreatography (ERCP) is indispensable in everyday surgical practice. Despite this, as an invasive procedure, it has its own mortality and morbidity, the most feared of which is periduodenal perforations. Our experience with ERCP related periduodenal perforations and its treatment strategies are presented. Additionally, a rarely encountered subtype is highlighted.

Methods

Patients who underwent ERCP and sustained a periduodenal perforation between August 2008 and October 2011 were reviewed.

Results

During the period from August 2008 to October 2011, 597 ERCP procedures were performed in our hospital. Ten of these patients (3 male, 7 female) had a perforation. The mean patient age was 56.6 years. During the procedure, injury was suspected in four patients; it passed unnoticed in the remaining six. The decision to operate or follow a conservative policy was based on a combination of clinical and radiological findings. Operative intervention was required in three patients, with one mortality, while conservative treatment was followed in the remaining seven. A laparotomy was performed early in two patients whereas it was performed after an initial period of conservative treatment in one. The presence of periduodenal fluid collection, contrast extravasation or free intraperitoneal air were decisive factors for performing laparotomy.

Conclusions

ERCP-related periduodenal perforations include different categories. Certain types require operative repair while others should be treated conservatively. The choice of the management approach should be individualised, depending on the clinical picture and radiological findings. Although rare, these are potentially serious complications that may end fatally. Early recognition and appropriate intervention is the only way to avert a fatal outcome.  相似文献   
85.
OBJECTIVE: To assess height and body mass index standard deviation scores up to 20 years after treatment for acute lymphoblastic leukaemia (ALL). SUBJECTS AND METHODS: Height and body mass index standard deviation scores were measured in 33 patients (14 boys and 19 girls) with childhood ALL at diagnosis, after the end of treatment, at final height, and at follow up 10-20 years (median, 16.2) after diagnosis. Eleven patients were treated with chemotherapy only and 22 patients were treated with chemotherapy and cranial irradiation. RESULTS: In the chemotherapy only group, height standard deviation scores were the same at follow up as at diagnosis, but there was a significant decrease in height standard deviation scores during treatment. Mean body mass index standard deviation scores increased steadily from the start of treatment until final height and continued to increase from final height until follow up. In the cranially irradiated group, mean height standard deviation scores decreased steadily from the start of treatment until follow up. Mean body mass index standard deviation scores increased continuously from the start of treatment until final height and from final height until follow up. CONCLUSION: Chemotherapy combined with cranial irradiation and chemotherapy alone might be persisting risk factors for obesity even after final/height has been attained in patients treated for childhood ALL. Chemotherapy is a risk factor for reduced final height only when administered in combination with cranial irradiation. These problems need to be recognised and dealt with at follow up examination.  相似文献   
86.
87.
88.
The aim of this study was to evaluate whether maternal diabetes in pregnancy may adversely affect the children's behavioral adjustment, in a sample of 201 mothers (68 with pre-gestational diabetes, 50 with gestational diabetes, and 83 with non-diabetic pregnancies) and their singleton offspring. After accounting for socioeconomic status, ethnicity and maternal attitudes, none of the Child Behavior Checklist ratings correlated significantly with maternal patient group or several indices of antepartum maternal metabolism. Child obesity, a common sequela of diabetic pregnancies, correlated positively with Internalizing Behavior problems and three narrow-band sub-scales: Somatic Complaints, Anxious/Depressed, and Social Problems. Results suggest that children of diabetic mothers are at increased risk for a variety of developmental disturbances. Screening for learning and behavioral difficulties should be made at regular pediatric visits, with follow-up evaluations warranted by positive indications, excessive weight gain, or other evolving medical concerns.  相似文献   
89.
Witschi  H; Espiritu  I; Yu  M; Willits  NH 《Carcinogenesis》1998,19(10):1789-1794
Male and female strain A/J mice were exposed to a mixture of cigarette sidestream and mainstream smoke at a chamber concentration of total suspended particulates of 82.5 mg/m3. Exposure time was 6 h/day, 5 days/week for 5 months. The animals were allowed to recover for another 4 months in filtered air before sacrifice and lung tumor count. Male animals were fed either 0.2% N-acetylcysteine (NAC) or 0.05% phenethyl isothiocyanate (PEITC) in diet AIN-76A with 5% corn oil added. Female animals received normal laboratory chow and were given a 1.25% extract of green tea in the drinking water. Corresponding control groups were fed diets without NAC or PEITC or given plain tap water. Exposure to tobacco smoke increased lung tumor multiplicity to 1.1-1.6 tumors/lung, significantly higher than control values (0.5-1.0 tumors/lung). None of the putative chemopreventive agents (NAC, PEITC or green tea extract) had a protective effect. In positive control experiments, PEITC significantly reduced both lung tumor multiplicity and incidence in mice treated with the tobacco smoke-specific carcinogen 4- (methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK). In mice treated with three different doses of urethan and fed NAC in the diet, a significant reduction in lung tumor multiplicity was found only at one dose level. Green tea extract did not reduce lung tumor multiplicity in animals treated with a single dose of NNK. It was concluded that successful chemoprevention of tobacco smoke-induced lung tumorigenesis might require administration of several chemopreventive agents rather than just a single one.   相似文献   
90.
The assignment of paternity when the alleged father has died is now possible by use of a variety of allele-specific oligonucleotides after amplification of genomic DNA by the polymerase chain reaction (PCR). Issues relating to the inheritance of estates may be decided on fact rather than allegation. PCR-based genotyping of DQ alpha haplotypes from paraffin-embedded tissue of the deceased was used to prove non-paternity in the case reported here. Because the child was female, it was also possible to confirm the exclusion by using a second polymorphic site located in the factor VIII gene on the X chromosome.  相似文献   
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