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31.
Fifty women with polycystic ovaries took part in a prospective randomized study. All women required treatment by in-vitro fertilization (IVF) for reasons other than anovulation. They had all previously undergone ovarian stimulation with gonadotrophin therapy which had failed to result in pregnancy or had been abandoned due to high risk of developing ovarian hyperstimulation syndrome (OHSS). Twenty-five women were treated by long-term pituitary desensitization followed by gonadotrophin therapy, oocyte retrieval and embryo transfer (group 1). Twenty-five women underwent laparoscopic ovarian electrocautery after pituitary desensitization followed by gonadotrophin therapy, oocyte retrieval and embryo transfer (group 2). A significantly higher number of women in group 1 had to have the treatment cycle abandoned due to impending or actual OHSS, determined by endocrine and clinical findings. In addition, the development of moderate or severe OHSS in completed cycles was higher in group 1. The pregnancy rate and miscarriage rates in the two treatment groups were similar. The authors propose that laparoscopic ovarian electrocautery is a potentially useful treatment for women who have previously had an IVF treatment cycle cancelled due to risk of OHSS or who have suffered OHSS in a previous treatment cycle.   相似文献   
32.

Background  

The purpose of the present investigation was to determine if the salivary counts of 40 common oral bacteria in subjects with an oral squamous cell carcinoma (OSCC) lesion would differ from those found in cancer-free (OSCC-free) controls.  相似文献   
33.
The rate of release of five amino acids (alanine, glutamine, glutamic acid, glycine, GABA) from the surface of the sensorimotor cortex has been determined in rabbits under local anesthesia immobilized with gallamine. Concomitant recording of the electroencephalogram and of blood pressure has been carried out. The scope of the research was to determine if a difference in the release of these aminoacids could be correlated with variations in cerebral electrical activity. Two open-ended silver cylinders were adapted to the cortex and filled with saline. Every 10 min, the liquid was removed and assayed using a dansylating procedure followed by thin layer chromatographic separation and fluorimetric determination of the amino acids. The EEG of non treated animals, followed for a period of 100 min, remained synchronized for the majority of the recording; the biochemical determinations indicated a slight but constant fall in the rate of release of all the amino acids. A significant increase in the release accompanied the EEG desynchronisation induced either with eserine (0.2 mg/kg), amphetamine (2 mg/kg), or with electrical stimulation of the reticular formation.  相似文献   
34.
Among the medical physics community, there is nowadays a great interest in the possible implementation of scatter imaging techniques, especially in the field of breast imaging. It is well known that malignant lesions and normal tissue differ in their scattering signatures, and thus scattered radiation can provide a powerful tool to distinguish between the two cases. Up to now, most of the proposed techniques rely on the detection of radiation scattered at angles of the order of a few degrees, which in most cases results in very high contrast values. On the other hand, at those relatively large angles the scattered flux is relatively low with respect to the primary, which often implies the necessity of increasing the dose delivered to the sample in order to achieve sufficient statistics. Furthermore, most of these techniques are based on pencil beam set-ups, which results in an increase of the overall duration of the examination. We propose here an alternative approach based on the detection of radiation scattered at extremely small angles, of the order of approximately 100-200 microrad. This results in a relatively high scattered flux (5-10% of the primary) and in the possibility of utilizing a fan beam geometry, which reduces the acquisition times with respect to pencil beam set-ups. Images of several samples have been acquired, demonstrating that the proposed technique results in an increased contrast with respect to absorption imaging. Possible in vivo implementations of the technique at no dose expense are finally discussed.  相似文献   
35.
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   
36.
Post-infusion hepatitis is known to occur very frequently in haemophiliacs after treatment with unheated commercial clotting factor concentrates, obtained from large plasma donation pool. On the contrary, single-donor cryoprecipitate is likely to carry a lower risk of transmitting hepatitis. To evaluate this hypothesis, we retrospectively reviewed the medical records of 25 first infused haemophiliacs (from 1981 to 1984) treated with unheated commercial clotting factor concentrates (n = 19) or cryoprecipitate (n = 6). The hepatitis-free interval after the beginning of therapy was expressed as exposure days. The end point of each patient, i.e. the hepatitis occurrence, was defined as an increase of amino-transferases (ALT and AST) and/or the seroconversion of HBV-markers, which were checked every three months. The life-table method and log-rank test showed that cryoprecipitates had a significantly longer hepatitis-free interval (p = 0.0131, log-rank test) and a lower risk of transmitting hepatitis (p = 0.01-0.05, life-table method) than the commercial concentrates. However, the safety of cryoprecipitate therapy was shown to cover only a few exposure days, and so the real advantage of this product depends on the bleeding frequency of the patient concerned. We believe that these methods and our findings may be useful to assess and compare the safety of the new "heat-treated" clotting factor concentrates.  相似文献   
37.
DeDonno  M. A.  Longo  J.  Levy  X.  Morris  J. D. 《Journal of community health》2022,47(4):627-634
Journal of Community Health - Early in the pandemic and prior to the development of the COVID-19 vaccine, prevention measures were promoted to help inhibit the spread of the virus. To optimize...  相似文献   
38.
Patterns and prognosis ofClostridium difficile colitis   总被引:2,自引:2,他引:0  
The incidence of Clostridium difficile colitis has increased during recent years, presumably because of liberal use of broad-spectrum antibiotic regimens. METHODS: A retrospective review to determine patterns of C. difficile colitis development, morbidity, and treatment results was undertaken. During an 18-month period, 90 patients were diagnosed with C. difficile colitis by fecal toxin assays. Patient demographics, symptoms, previously administered antibiotic regimens, diagnostic evaluations, treatment modalities, morbidity, and mortality were identified, entered into a computer data base, and analyzed. RESULTS: The mean age was 58 years; males outnumbered females 1.21. Among 90 patients, 41 (46 percent) developed C. difficile colitis after surgical procedures. Eighty (89 percent) patients received antibiotic therapy before developing C. difficile colitis: 35 (44 percent) for documented infections and 45 (56 percent) as empiric or prophylactic therapy. Cephalosporins, penicillins, quinolones, vancomycin, and aminoglycosides were the most frequently administered antibiotic classes prior to C. difficile colitis diagnosis. Ten (11 percent) patients developed C. difficile colitis without previous antibiotic therapy. Eighty-two (91 percent) patients presented with diarrhea, while eight (9 percent) had fever only. Primary C. difficile colitis treatment for both groups included vancomycin (66 percent), metronidazole (24 percent), or both drugs (10 percent). Ten (11 percent) patients received no treatment. No patient developed toxic colitis or megacolon. Colonoscopy was performed in four (4 percent) patients; pseudomembranes were identified in one (25 percent) patient. There was one C. difficile colitis recurrence after treatment, but no C. difficile colitis-associated morbidity. Mortality (14 patients, 16 percent) was not related to C. difficile colitis, but to underlying illness. No difference in patient age, sex, previous antibiotic administration, serum albumin, total days hospitalized, duration of C. difficile colitis antibiotic therapy,C. difficile colitis treatment regimens, or mortality was identified between nonsurgical and surgical patients. The white blood cell count was significantly lower in the nonsurgical group however.Clostridium difficile colitis developed most commonly after antibiotic administration with symptoms of diarrhea, but did occur without previous antibiotic administration or diarrhea. CONCLUSION: Despite the clinical setting,C. difficile colitis had no associated morbidity and treatment was highly effective. Mortality was related to underlying medical illness, not C. difficile colitis.Read at the meeting of The American Society of Colon and Rectal Surgery, Chicago, Illinois, May 2 to 7, 1993.  相似文献   
39.
40.
We conducted a phase I/II trial of 5-fluorouracil (5-FU), calcium leucovorin (LV), zidovudine (AZT) and dipyridamole (DP), (FLAP) in patients with metastatic colorectal cancer, renal cell carcinoma and malignant melanoma. AZT and DP were given to enhance the biochemical modulation and antitumor activity of 5-FU and LV. All patients received 5-FU (370 mg/m(2) i.v. bolus day 0-4), LV (50 mg/m(2) p.o. every 4 h day 0-4) and DP (50 mg/m(2) p.o. every 6 h days 0-27). In the phase I portion of the study, AZT was dose escalated in cohorts of 5 patients each, from 50 mg p.o. every 6 h days 0-27 to the MTD of 200 mg p.o. every 6 h days 0-27. Thirty-three patients received 200 mg of AZT in the phase II portion of the trial. Eleven patients developed grade III and 5 patients developed grade IV leukopenia. Four patients developed grade III and 21 patients developed grade IV neutropenia, with six febrile neutropenic episodes. Six patients experienced grade III anemia and four grade III thrombocytopenia. Diarrhea or stomatitis of greater than or equal to grade III occurred in six and four patients, respectively. Fifty-eight percent (19 of 33) of patients required dose reductions of AZT for hematologic toxicity (13 of 19 in the first treatment cycle). At the 200 mg AZT dose level, there were two partial responses in nine colorectal cancer patients (22%), no objective responses in 14 patients with renal cell carcinoma or in 14 patients with melanoma. FLAP does not have significant activity in melanoma, renal cell carcinoma or 5-FU-treated colorectal cancer patients, although it may have activity in untreated colon cancer.  相似文献   
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