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2.1. History and clinical-gynecological investigation including a Pap smear are the first step in the clarification.The history should make sure if there is in fact bleeding from the genital and not from the urological or the intestinal region.Drug intake should be recorded, and risk factors for the development of endometrial carcinoma should be considered. This will not affect further investigation.The clinical-gynecological investigation should prove the source of postmenopausal bleeding according to the anatomical site--uterine, infra-, or suprauterine. The causes of infrauterine bleeding may easily be diagnosed by means of inspection of the external genitalia and further by using a speculum. The causes of uterine bleeding are of major importance. Cytology and colposcopy, supported by bimanual investigation, exclude cervical carcinoma as a cause of bleeding. Atypical endometrial cells on the cytological smear arouse suspicion of endometrial carcinoma. 2.2. Transvaginal sonography (TVS) is the next step if the above-mentioned investigations are negative. Both adnexa should always be investigated and the findings sonographically documented, so that solid cystic masses in the adnexal area can be better identified as suprauterine causes of postmenopausal bleeding. Then the uterus should be investigated. Further procedures are decided from the results of measurement of the longitudinal section of the endometrium at the level of maximum endometrial thickness.If the endometrial thickness is _<4 mm, an observant attitude can be assumed. After 3 months the patient should be controlled against using TVS. If bleeding recurs or the endometrial thickness is >4 mm on TVS, the procedure given in subparagraph 2.3 should be followed. In case the endometrial thickness is >4mm or not measurable, a histomorphological investigation according to subparagraph 2.3 should be performed. In such cases, saline infusion sonohysterography(SIS) is useful as a simple method to supplement TVS. It can aid in the decision making as to which further, more invasive measures should be taken (endometrial biopsy/hysteroscopic resection). Computerized tomography or magnetic resonance imaging are, as a rule, not indicated in patients with postmenopausal bleeding. 2.3. A definite diagnosis is possible only on the basis of a histological investigation. If TVS or SS show evidence of a polypoid state, removal under hysteroscopic control is the diagnostic method of choice. In cases of symmetrical or asymmetrical thickening of the endometrium on SIS, a less invasive biopsy may be sufficient. If the biopsy specimen does not yield representative diagnostic material, one should proceed as described above. A fractionated curettage should as a rule not be performed solely, but in combination with hysteroscopy.  相似文献   
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This study was conducted to investigate the effectiveness and safety of endoluminal tubal coagulation in obliterating the tubal lumen in rabbits. Forty female rabbits were subjected to laparotomy and hysterotomy. Endoluminal tubal coagulation was induced over a length of 3 cm in the proximal, extramural fallopian tube by using a heated stainless steel cannula or a cylindrical diffusing tip emitting argon laser radiation for one to 5 minutes. Tubal patency was evaluated by observing patterns of injected methylene blue and/or breeding success rates. Postoperative recovery was uneventful in all animals. A negative methylene blue test indicated occlusion in 51 of 52 tubes (tubal occlusion rate 98.1%), and a contraception rate of 100% in all 17 uteri in which the tube had been treated. The described endoluminal tubal coagulation method proved suitable for safe and effective sterilization in rabbits and has potential as a new transcervical tubal sterilization method for humans.  相似文献   
106.
Weaver  DA; Hei  TK; Hukku  B; McRaven  JA; Willey  JC 《Carcinogenesis》1997,18(6):1251-1257
To establish a cell culture model for lung carcinogenesis, independent populations of the human papillomavirus 18-immortalized human bronchial epithelial cell line BEP2D were treated with high linear energy transfer radon-simulated alpha-particles, expanded and xenotransplanted into Nu/Nu mice. Six independent cell lines were established from tumors that developed from three separate radiation treatments as follows: treatment (Tx) 1 (30 cGy--two doses), H2BT, Tx 2 (30 cGy-- single dose), R30T1L, R30T2 and R30T3L, Tx 3 (30 cGy--single dose), H1ATN and H1ATBA1. Cytogenetic analysis revealed common changes in all tumor lines: loss of the Y chromosome (ch), one of three copies of ch8, one of three copies of ch14, and one of two copies of ch4p16-pter and ch11p15-pter. Analysis of polymerase chain reaction-amplified short tandem repeats of informative loci confirmed the loss of chY in all lines and loss of heterozygosity (LOH) at eight loci spanning the length of ch8 in all lines from Tx's 1 and 2. Our data support previous studies indicating the presence of tumor suppressor genes on ch8. LOH also was confirmed on ch14 at locus D14S306 in all cell lines from Tx 2 and in one of two lines from Tx 3. This region, 14q12-q13, may contain changes in one of the five known somatostatin receptor genes (SSTR1). No LOH was detected at any of the informative loci tested for on ch4 or ch11.   相似文献   
107.
Childhood tuberculosis is perceived by many as a disease of the past. Experience in a children's hospital serving a deprived population suggested that tuberculosis and other mycobacterial infections were not declining in clinical practice. Fifty three tuberculous and 11 atypical mycobacterial infections were identified between 1978 and 1992. There was no decline in tuberculosis and nine of the 11 atypical infections occurred in the last five years. Altogether 40% of cases of tuberculosis were in non-Asian children; 32% had arrived in the UK or visited family overseas in the previous year; and 38% had a history of tuberculosis contact, usually a close adult relative. Nationally, the previous decline in tuberculosis in all ages has reversed. In the local health districts in London's east end, childhood tuberculosis has also stopped declining and seems to be increasing. It is regrettable that BCG vaccination has been abolished by some districts in the UK, against current recommendations. Childhood tuberculosis is still common in the practice described here, including among children who do not fall into conventionally recognised high risk groups. Inner city dwellers and junior doctors are both highly mobile populations, adding to the risk that paediatricians, particularly those in training, may encounter tuberculosis with little or no previous experience of the condition.  相似文献   
108.
A prospective trial of warfarin and dipyridamole was performed in patients with membranoproliferative glomerulonephritis. Eighteen completed either a control or treatment year, and 13 completed both a control and treatment year. To obviate the bias of excluding control patients who had renal failure after one year, both an unpaired and a paired analysis were performed. The unpaired analysis compared 10 patients followed for an initial control year with eight patients receiving treatment first. Renal function remained stable over the year in the treated group, but worsened in the control group. Slopes of regression lines for reciprocal serum creatinine values were significantly different between groups (p < 0.025). Urine protein excretion also decreased in the treated group. Four of 10 control patients had a two-fold increase in serum creatinine levels, but no treatment patient did. In the paired crossover analysis, significant differences in renal function were detected between control and treatment years in six patients whose renal function significantly changed over one of the years. In every instance, there was better preservation of renal function in the treatment year. Urinary protein also decreased significantly over the treatment year compared with the control year. Bleeding was the most frequent complication. These data suggest that warfarin and dipyridamole have a beneficial effect on renal function in membranoproliferative glomerulonephritis.  相似文献   
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Multisection, dual-echo magnetic resonance (MR) transaxial images of blood vessels contain both anatomic and qualitative information about flow. Even so, the images are produced as a series of two-dimensional tomographic sections from which full visualization of connected structures is difficult. A computer algorithm was developed that automatically detects flowing blood based on pixel intensity and calculated T2 and provides reconstructed views of vessels while analyzing and displaying flow characteristics. Images of abdominal vessels, aortic aneurysms, and the heart were encoded by flow and color to demonstrate depth. In addition, these data were reconstructed to derive a more accurate assessment of patency. With this technique, transaxial images can be used to analyze flow patterns, determine patent areas, and visualize all levels of vessels in a single image.  相似文献   
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