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21.
22.
We report a rare case of early-stage endometrial adenocarcinoma in a 22 year old nullipara with polycystic ovaries undergoing conservative treatment. Pretreatment evaluation including tumour grade, depth of myometrial invasion, tumour size, hormone receptor status and flow cytometric analysis indicated a favourable prognosis. The patient underwent repeat endometrial curettage and a 6 month period of therapy with megestrol acetate and tamoxifen. A combination contraceptive pill was then prescribed to ensure withdrawal of the menstrual cycle thereafter. Now, 1 year after the last curettage, there is no evidence of disease. During the treatment period, hysteroscopy allowed for a more precise approach in panoramically examining the tumour nest in the endometrial cavity, and the subsequent endometrial response to hormone therapy. Laparoscopy using bulldog clamps applied to the isthmic portion of the Fallopian tubes prevented i.p. spread of endometrial tissue from retrograde regurgitation during hysteroscopy. Laparoscopic ovarian electrocautery resulted in the reduction of abnormal hypervascularization on the surface of polycystic ovaries postoperatively but caused a peri-ovarian adhesion complication. It is interesting that this case posed a unique opportunity to demonstrate the tumour regression under the assistance of laparoscopy and hysteroscopy.   相似文献   
23.
The gene for the most frequent from of X-linked retinitis pigmentosa (XLRP), RP3, has been assigned by genetic and physical mapping to a segment of less than 1000 kbp, which is flanked by the marker DXS1110 and the ornithine transcarbamylase (OTC) gene. In search of microdeletions, we have screened the DNA of 30 unrelated patients with XLRP by employing a representative set of YAC-derived DNA fragments that were generated by restriction enzyme digestion and PCR amplification. In one of these patients, a 6.4 kbp microdeletion was detected which was not present in the DNA of 444 male controls. A cosmid contig spanning the deletion was constructed and used to isolate cDNAs from retina-specific libraries. Exons corresponding to these expressed sequences as well as other putative exons were identified by sequencing more than 30 kbp of the critical region. So far, no point mutations in these putative exon sequences have been identified.   相似文献   
24.
The gene for retinitis pigmentosa 3 (RP3), the most frequent form of X- linked RP (XLRP), has been mapped previously to a chromosome interval of less than 1000 kbp between the DXS1110 marker and the OTC locus at Xp21.1-p11.4. Employing a novel technique, YAC Representation Hybridization (YRH)', we have recently identified a small XLRP associated microdeletion in this interval, as well as several putative exons including the 3' end of a gene that was truncated by the deletion. cDNA library screening and sequencing of a cosmid centromeric to the deletion has now enabled us to identify numerous additional exons and to detect several point mutations in patients with XLRP. The predicted gene product shows homology to RCC1, the guanine-nucleotide- exchange factor (GEF) of the Ras-like GTPase Ran. Our findings suggest that we have cloned the long-sought RP3 gene, and that it may encode the GEF of a retina-specific GTP-binding protein.   相似文献   
25.

Background

Few studies have investigated the initial prodrome of bipolar disorders, and none has explicitly addressed bipolar II disorder (BD-II). We explored symptoms and behaviors preceding the first major affective episode (FMAE) of BD-II to generate hypotheses concerning possible clinical targets for early intervention.

Methods

In-depth interviews of 15 BD-II patients and 22 family informants were carried out. Clinical diagnoses were reassessed. The textual data of transcribed interviews were analyzed utilizing qualitative methodology supplemented by quantitative analyses.

Results

All patients experienced clinically significant symptoms and behaviors at an average of more than a decade before the FMAE. Anxiety and depression-type symptoms were the most common. Two distinct subgroups were identified based on prominent and enduring personal characteristics prior to the FMAE. The individuals in one of the subgroups were described as very well-functioning, whereas the individuals in the other subgroup were characterized by neurocognitive deficits, relatively low academic and social functioning, and pronounced irritability and aggressiveness. Furthermore, it is possible that these individuals experience earlier prodromal symptom onset, earlier FMAEs, and more symptoms than individuals without these characteristics.

Limitations

This is a retrospective and hypothesis-generating qualitative study. The hypotheses generated need to be tested in future studies.

Conclusions

Prodromal clinical phenomenology is too nonspecific to predict the occurrence of the FMAE of BD-II. However, identifiable subgroups may exist. We hypothesize that neurocognitive deficits together with pronounced irritability and aggressiveness may constitute a vulnerability marker for a subgroup of individuals who subsequently develop BD-II. This subgroup may be of potential interest for early identification.  相似文献   
26.
BackgroundThe role of sexual activity in hepatitis C virus (HCV) transmission remains controversial. Studies to date have not explored the relationship between HCV shedding in cervicovaginal fluids and the presence of menstrual or other blood.ObjectivesSince cross-sectional studies may underestimate the prevalence of viral shedding, we performed a 56-day longitudinal study of cervical HCV shedding.Study designWomen self-collected cervicovaginal swabs for 56 consecutive days, while keeping a diary of menses and genital symptoms. Swabs were tested for HCV RNA and cellular DNA by quantitative PCR, and hemoglobin by spectrophotometry.ResultsSixteen women contributed a total of 701 cervicovaginal swabs (mean collection period 48 days, range 18–56). Detection of HCV RNA was associated with detection of hemoglobin. Premenopausal women were more likely than post-menopausal women to have HCV RNA detected in cervicovaginal fluids. For premenopausal women, detection of HCV RNA was more likely during menstruation (OR = 56.4) or when hemoglobin was detected in cervicovaginal fluids, even if menstruation was not occurring (OR = 35.4). No woman post-hysterectomy had HCV RNA detected in cervicovaginal fluids on any day, regardless of whether hemoglobin was detected.ConclusionsOur findings are consistent with a low likelihood of sexual transmission of HCV. The results suggest that shedding of HCV RNA in the female genital tract is associated with the presence of blood, and requires the presence of a cervix. Clinicians should consider advising premenopausal women who are concerned about transmitting infection that infectivity may increase during menstruation.  相似文献   
27.
Longitudinal data were analyzed to determine changes in willingness to participate in HIV vaccine efficacy trials and knowledge of vaccine trial concepts among populations at high risk of HIV-1 infection. Gay men (MSM), male and female injection drug users, and non-injecting women at heterosexual risk were recruited (n = 4892). Follow-up visits occurred every 6 months up to 18 months. Willingness was significantly lower at follow-up visits compared with at baseline. Knowledge levels increased for all study populations. Problematic concepts were possible effects of the vaccine on the immune system and lack of knowledge about efficacy of a vaccine before the start of a trial. For concepts concerning safety, blinding, and guarantees of future participation in trials, MSM men had significant increases in knowledge, but little to no change occurred for the other populations. An increase in knowledge was associated with becoming not willing, particularly among MSM with low knowledge levels. At least half of high-risk participants were consistently willing to participate in future vaccine efficacy trials and with basic vaccine education, knowledge levels increased. Continued educational efforts at the community and individual level are needed to address certain vaccine trial concepts and to increase knowledge levels in all potential study populations.  相似文献   
28.
Developmental changes in multifrequency tympanograms   总被引:4,自引:0,他引:4  
The normal maturational course of tympanometric shape, static aural acoustic admittance and ear canal wall characteristics were investigated in healthy infants, who were followed at various time intervals in the first 4 months of life. Susceptance and conductance tympanograms were recorded from both ears of each subject at four probe frequencies or more. In addition, quantitative pneumatic otoscopy was performed utilizing air pressure changes of the same magnitude as those typically used in tympanometry. Results for the group were an increase in admittance magnitude with increasing age at frequencies above 226 Hz. Admittance phase angle increased with age at all frequencies, indicating a growing contribution of compliant elements in the first 4 months of life. The course of development of input admittance at the tympanic membrane differed among individual infants. Otoscopic findings indicated that external ear canal differences cannot completely account for tympanometric differences between young infants and adults.  相似文献   
29.
Background: We concluded a program in which we administeredradiotherapy only to clinical stages I and II Hodgkin's diseasepatients at standard risk, with the addition of 4 cycles ofcombination chemotherapy before radiotherapy for high-risk patients. Patients and methods: From 1980 to 1991, 313 patients with clinicalstages I or II Hodgkin's disease underwent treatment in ourhospital. Fifty percent of the patients in groups previouslyidentified as being at high risk for relapse received 4 cyclesof combination chemotherapy before radiotherapy. The remaininghalf of the patients received radiotherapy only. Results: Low- and high-risk patients aged 15–59 yearshad, respectively, complete remission (CR) rates of 97% and94%, 5-year survivals of 95% and 91%, and 5-year freedom fromrelapse (FFR) rates of 78% and 89%. Older low- and high-riskgroups had CR rates of 97% and 93%, 5-year survivals of 60%and 56% and 5-year FFR of 77% and 93%, respectively. Conclusion: Here we present our favorable results after treatingstandard-risk patients with clinical stages I and II Hodgkin'sdisease with radiotherapy only. With the addition of chemotherapy,the rate of relapse in the high-risk patients was reduced belowthat of the standard-risk patients. Overall survival was thesame for the high- and standard-risk patients. adjuvant chemotherapy, Hodgkin's disease, radiotherapy, stages I and II  相似文献   
30.
Postoperative ileus (PI) is a major contributor to postoperative morbidity and prolonged convalescence after major surgical procedures. The pathophysiology of PI is multifactorial, including activation of the stress response to surgery, with inhibitory sympathetic visceral reflexes and inflammatory mediators. We update evidence on the advances in the prevention and treatment on PI. As single interventions, continuous thoracic epidural analgesia with local anesthetics and minimally invasive surgery are the most efficient interventions in the reduction of PI. The effects of pharmacological agents have generally been disappointing with the exception of cisapride and the introduction of the new selective peripherally acting m-opioid antagonists. Presently, introduction of a multi-modal rehabilitation programme (including continuous epidural analgesia with local anesthetics, early oral feeding and enforced mobilization) is the most effective technique to reduce PI in abdominal procedures.  相似文献   
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