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921.
PURPOSE: A large number of medical centers have recently instituted the use of High Dose-Rate Afterloading Brachytherapy (HDRAB). There is wide variation in treatment regimens, techniques, and dosimetry being used and there are no national standard protocols or guidelines for optimal therapy. METHODS AND MATERIALS: The Clinical Research Committee (CRC) of the American Endocurietherapy Society (AES) met to formulate consensus guidelines for HDRAB in cervical, endometrial, and endobronchial tumors. CONCLUSION: Each center is encouraged to follow a consistent treatment policy in a controlled fashion with complete documentation of treatment parameters and outcome including efficacy and morbidity. Until further clinical data becomes available, the linear quadratic model can be used as a guideline to formulate a new HDR regimen exercising caution when changing from a Low Dose Rate (LDR) to a HDRAB regimen. The treatments should be fractionated as much as practical to minimize long term morbidity. As more clinical data becomes available, the guidelines will mature and be updated by the Clinical Research Committee of the AES.  相似文献   
922.
The native Australian marsupial Phascolarctos cinereus, otherwise known as the koala, is prone to infection by the obligate intracellular parasite Chlamydia psittaci, which causes ocular 'pink eye' and urogenital 'dirty tail' diseases. Several chlamydial DNA probes to both chromosomal and plasmid sequences were used to type by Southern blot analysis 51 samples taken from wild and captive koalas from habitats on the eastern seaboard of Australia as far apart as Queensland and Victoria. Two types of C. psittaci were observed and called types I and II. Type II was found more frequently than type I and occurred in both ocular and urogenital samples, while type I showed a strong but not absolute preference for ocular sites. Cross-hybridization analyses indicated that type I and type II had about 10% DNA sequence identity to each other. DNA analyses showed that type II was very closely related to some ovine and bovine chlamydiae but type I could not be related to any other C. psittaci strain available. Light and electron microscopic analyses of infected BGM monolayers revealed that the two strains were similar in morphological characteristics. The type I strain was considerably more infectious than the type II strain in BGM cells and in the yolk sacs of embryonated eggs. A PCR based assay detected both type I and type II koala chlamydiae in samples that had been negative by Southern blot and tissue culture and provided the first evidence that both types can occur simultaneously at the one site of infection.  相似文献   
923.
Between 1985 and 1990, a study of 5313 lactations of 2477 Black and White cows was carried out. A stepwise least squares method was used to obtain unbiased estimates of milk, fat, and protein losses that were due to clinical mastitis and the carry-over effect from the previous lactation. Logistic regression was used to estimate the probability that a cow would have clinical mastitis in the next month. The effect of clinical mastitis on production within one lactation was estimated at 527 kg of milk (8.1%), 22.7 kg of fat (8.0%), and 13.7 kg of protein (6.2%) for > or = 3 cases of clinical quarters in the second lactation. One or 2 cases of clinical quarters in a lactation did not significantly affect the production in the next lactation. The negative carry-over effect of > or = 3 cases of clinical quarters was estimated at 381 kg of milk (5.9%), 23.7 kg of fat (8.4%), and 10.1 kg of protein (4.6%) up to and including mo 8 of the second lactation. The fat content in milk produced after the onset of mastitis decreased, and the protein content increased. The risk of clinical mastitis infection in the following month was influenced by month of lactation (a higher risk early in lactation), lactation number (risk increased with lactation number), production level (higher risk for high producing cows), number of clinical quarters in the previous lactation, number of clinical quarters in the previous months of the current lactation, and occurrence of clinical mastitis in the current month.  相似文献   
924.
Correlations between specific binding of labeled adrenoligands in the frontal cortex and hypothalamus and peripheral blood plasma testosterone were studied in BALB/cLac, CBA/Lac, and S57BL/6J male mice. A negative correlation was detected between blood testosterone and the extent of specific binding of 3H-clonidine, a 1.6 nM alpha 2-adrenoceptor agonist, in the hypothalamus. No correlations were revealed between specific binding of 3H-clonidine in the frontal cortex and binding of the rest radioligands (0.4 nM alpha 1-adrenoceptor antagonist 3H-prazosin and 1.6 nM beta-adrenoceptor antagonist 3H-dihydroalprenolol) in both brain segments and blood testosterone level. Further experiments in six mouse strains (A/He, BALB/cLac, CBA/Lac, C57BL/6J, DD, and YT) revealed a reliable negative genotypic correlation between hypothalamic maximal specific binding of 3H-clonidine and testosterone level. The detected feedback may be an important regulatory mechanism of the hypothalamo-hypophyseo-gonadal system in male mice.  相似文献   
925.
Plasma sIl-2R and sCD8 levels of 12 patients with renal cell carcinoma were determined before and during subcutaneous rIl-2 therapy. Patients with a complete/partial remission showed a significantly stronger initial increase of sCD8 compared to patients with stable disease or tumour progression.  相似文献   
926.
A total of 45 patients aged 35 to 73 years who had sustained acute myocardial infarction (MI) were studied in a special cardiological unit. On days 1, 5, 14, 28 of hospital stay, each patient underwent measurements of cortisol, insulin, T3 and T4 and calculations of the mathematical clinic severity index after G.I. Marchuk et al. In acute MI, there were elevated plasma levels of cortisol depending on the MI severity with a small repeated peak of its increase on day 14 and its subsequent decrease, except deaths. In severe acute MI there were impairments of reciprocal cortisol/insulin ratios. This was particularly pronounced in patients with lethal outcomes. By the end of hospital rehabilitation, patients with acute MI displayed lower levels of thyroidal hormones. The maximum decrease in T3 and T4 was found in patients with lethal outcomes. There was a direct correlation between the mathematical clinical severity index of the natural history of acute MI and the levels of cortisole triidothyronine at the hospital stage of observation. In the course of the study it was found that the Marchuk clinical severity index serves as an informative severity index of MI course whose determination in its acute period allows one to predict the course of acute MI and to choose a differential therapy of and to make a diagnosis of possible complications.  相似文献   
927.
In capable male population (age 20-59 years) developing oil and gas extraction in the Western Siberia the incidence of arterial hypertension reached 14.1%. Wide introduction of preventive programs in the extreme conditions of labour helped to normalize blood pressure in every second patient and to maintain health in migrants from other regions.  相似文献   
928.
Analysis of case histories and clinical and direct immunofluorescent examinations of 72 patients enabled the authors to single out 3 forms of complicated adenovirus keratoconjunctivitis (AVKC): 1) acute grave; 2) with toxic allergic reaction to previous treatment; and 3) steroid-complicated. Recommendations on the treatment of these forms are offered. A common remedy is interferon inductor poludan and chigain obtained from human colostrum and containing secretory IgA. Poludan was administered by instillations (4-6 times a day) and periocular injections in a dose of 100 U every 1-2 days, 5-6 injections per course, chigain was administered by instillations (2-4 daily). This combined treatment was highly effective and well tolerated. Periocular injection of poludan ensured much more intensive local and even systemic interferon production than instillations alone. Mean terms of treating complicated AVKC were compatible with those in uncomplicated forms: 14.3 +/- 2.1 vs. 13.2 +/- 1.2 days, respectively. Signs of herpesvirus infection were detected in one-third of patients with steroid-complicated AVKC. For eliminating corneal opacities in AVKC patients, enzyme phonophoresis, phototherapeutic keratectomy, and (in grave cases) lamellar keratoplasty are recommended.  相似文献   
929.
The OX-40 receptor, a member of the nerve growth factor/tumor necrosis factor receptor gene family, is expressed preferentially on autoreactive CD4+ T cells isolated from the site of inflammation in rats with clinical signs of experimental autoimmune encephalomyelitis (EAE). To examine whether the OX-40 receptor has biologic relevance to T cell function, we evaluated the ability of a rat OX-40 receptor-specific antibody to co-stimulate a myelin basic protein (MBP)-reactive CD4+ T cell line. The anti-OX-40 antibody provided a potent co-stimulatory signal to CD4+ T cells when added in conjunction with a submitogenic dose of anti-CD3, but the anti-OX-40 antibody alone did not produce a mitogenic response. The magnitude and dose-response of anti-OX-40 co-stimulation was virtually identical to the signal delivered to T cells when cultured with anti-CD28 in conjunction with anti-CD3. MBP-specific T cells stimulated with both anti-CD3 and anti-OX-40 antibodies expressed increased mRNA and protein for IL-2 when compared to anti-CD3 alone. MBP-specific T cells stimulated with both anti-CD3 and anti-OX-40 antibodies were also able to induce EAE when transferred into naive Lewis rats. In contrast, cells stimulated with anti-CD3 alone were not encephalitogenic. These data suggest that the function of the OX-40 receptor on activated T cells is to provide an alternative pathway for T cell co-stimulation that may be similar in potency to the CD28-mediated signal.  相似文献   
930.
RT-PCR was used to assay for growth factors and receptors from seven different protein families in cochlea tissues of the juvenile rat. There was a broad representation of the growth factor families in all the cochlea tissues examined, though the organ of Corti and stria vascularis expressed a greater variety than the spiral ganglion. This broad expression suggests that a variety of known growth factors play significant roles in the development, maintenance, and repair of the inner ear. The results of this survey serve as a basis for the design of future in vitro experiments that will address the ability of growth factors to protect hair cells from damage and to evoke a repair-regeneration response by injured hair cells.  相似文献   
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