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41.
42.
Innovations in design of a dedicated breast scanner resulted in automation of the scanning process, the production of high resolution images of the whole breast and an efficient mode of image review. The results of clinical evaluation of the prototype of this breast scanner investigating normal breasts as well as benign and malignant breast lesions are presented.  相似文献   
43.
Abstract: The aim of this clinical study was to investigate the intensity of central pain in 18 patients. Each patient systematically recorded their own pain scores a total of 700 times (ie, 7 times/day for 100 consecutiv e days) using a standard four-point scale. In all 18 patients, the intensity of pain varied considerably (ranging in grade from no pain, mild pain, moderate pain to severe pain). During the 100 days, the average number of times (percentage of total) that each grade of pain intensity was scored was: no pain 7.4 (1.1%); mild pain 570.9 (81.6%); moderate pain 93.4 (13.3%), and severe pain 28.3 (4%). The difference between mild pain and moderate, severe, or no pain was significant. Thus, in our patient group the intensity of central pain was mostly mild, not severe. In contrast to other reports, our data suggest that to state that the intensity of central pain continues to be intolerable and severe throughout the day is an exaggeration. Among our 18 patients, an exacerbation of pain intensity was observed 507 times. Of these 507 events, 392 (77.3%) were due to specifiable factors and 115 (22.7%) were due to unknown factors. The specifiable factors could be attributed to: emotional factors 261 times (66.6%), somatic stimuli 44 times (11.2%), weather 38 times (9.7%), fatigue 29 times (7.4%), visceral activity 20 times (5.1%). Since there is no universally effective treatment for central pain, the strategy to manage central pain should primarily focus (if possible) on prevention of the exacerbating factors of central pain.  相似文献   
44.
Brain structures located within the anterior wall of the third brain ventricle (subfornical organ, median preoptic nucleus and organum vasculosum of the lamina terminalis) are known to be involved in thirst as well as other aspects of body fluid and electrolyte balance. The present studies evaluated the role of these structures in the Na appetite of mildly or moderately Na-depleted sheep (sheep with a parotid fistula deprived of Na solution for 22 or 46 h). In addition, the role of these structures was tested in mildly Na-depleted sheep in which the Na appetite was enhanced by decreasing cerebrospinal fluid and brain extracellular fluid Na concentration (i.e., i.c.v. infusion of hypertonic saccharide solution) or was decreased by systemic infusion of hypertonic saline. The results indicated that sheep with lesions which reduced or eliminated daily water intake or water intake in response to hypertonicity of body fluids had, in all situations tested, appropriate changes in Na appetite (i.e., similar to their prelesion changes). Thus, the present experiments demonstrated that the brain areas involved in thirst as well as other aspects of body fluid and electrolyte balance are anatomically different from those involved in regulating Na appetite.  相似文献   
45.
Tuberous sclerosis: characteristics at CT and MR imaging   总被引:7,自引:0,他引:7  
Altman  NR; Purser  RK; Post  MJ 《Radiology》1988,167(2):527-532
Computed tomography (CT) and magnetic resonance (MR) imaging findings were reviewed in 26 patients with tuberous sclerosis. All patients underwent CT; 16 patients underwent both. The CT features included subependymal nodules in 25 of 26 patients (96%) and calcifications in 23 of 26 (88%). Parenchymal hamartomas (cortical tubers) were seen in 23 of 26 patients (88%). These lesions had less attenuation than surrounding brain in 16 of 26 patients (62%) and were calcified in 14 of 26 patients (54%). Contrast enhancement of a lesion, indicating a subependymal giant cell astrocytoma, occurred in three of 26 patients (12%). The MR imaging characteristics included subependymal nodules (periventricular nodules) of intermediate signal intensity in ten of the 16 patients (63%). Parenchymal hamartomas, demonstrated in 15 of the 16 patients (94%), usually exhibited long T1 and T2 relaxation characteristics. The pattern was noted to be reversed in the two newborn patients (13%). One parent demonstrated a forme fruste at CT but had a normal MR image.  相似文献   
46.
A study of 140 days duration was performed to examine if human male volunteers (n = 5) respond to ovine follicle stimulating hormone (oFSH) immunization (administered adsorbed on Alugel on days 1, 20, 40 and 70) by producing antibodies capable of both binding and neutralizing bioactivity of human FSH. The kinetics of antibody production for both the immunogen (oFSH) and the cross-reactive antigen (hFSH) were essentially similar. The volunteers responded only to the first two immunizations. The boosters given on days 40 and 70 were ineffective, probably because of the presence of substantial amounts of circulating antibody to oFSH. Of the antibodies generated to oFSH, 25-45% bound hFSH with a mean binding affinity of 0.65 x 10(9) +/- 0.53 M(-1). The binding capacities at the time of high (30-80 days of immunization) and low (>110 days) titres were 346 +/- 185 and 10.5 +/- 5.8 ng hFSH/ml respectively. During the period of high titre, free serum FSH (value in normal males 1-5 ng/ml) was not monitorable. A 50 microl aliquot of the antiserum obtained from different volunteers between days 30 and 80 and on day 140 blocked binding of (125)I-labelled hFSH to its receptor by 82 +/- 9.7 and 53 +/- 12.2% respectively. The antibody produced was specific for FSH, and no significant change in the values of related glycoprotein hormones (luteinizing hormone/testosterone and thyroid stimulating hormone/thyroxine) were recorded. Seminal plasma transferrin, a marker of Sertoli cell as well as of seminiferous tubular function, showed marked reduction (30-90%) following immunization with oFSH. Considering that endogenous FSH remained neutralized for approximately one sperm cycle only (65 days), the reduction in sperm counts (30-74%) exhibited by some volunteers is encouraging. Immunization with oFSH did not result in any significant changes in haematology, serum biochemistry or hormonal profiles. There was no production of antibodies capable of interacting with non- specific tissues. It is concluded that it should be possible to obtain a sustained long-term blockade of endogenous FSH action in men by using oFSH as an immunogen. This is a prerequisite for obtaining significant reduction in the quality and quantity of spermatozoa produced, thus leading to infertility.   相似文献   
47.
Human neutrophils are rescued from apoptosis following incubation with once-washed, fibroblast-derived Toxoplasma gondii tachyzoites. Both infected and uninfected neutrophils are rescued, implicating a soluble mediator. In this study we investigated the origin and identity of this soluble mediator. Neutrophils were incubated either with purified tachyzoites or with conditioned medium derived from T. gondii-infected human fibroblasts. Conditioned medium was found to be a potent stimulus that delayed neutrophil apoptosis up to 72 h, whereas purified and extensively washed tachyzoites had no effect. Delayed apoptosis correlated with up-regulation of the neutrophil antiapoptotic protein, Mcl-1, and the neutrophil interleukin 3 receptor alpha subunit (IL-3Ralpha), suggesting a role for granulocyte-macrophage colony-stimulating factor (GM-CSF). GM-CSF and granulocyte colony-stimulating factor (G-CSF) were measurable in conditioned medium by enzyme-linked immunosorbent assay. Neutralizing antibodies to GM-CSF and G-CSF were additive in abrogating delayed neutrophil apoptosis induced by conditioned medium. Inhibitors of Src family tyrosine kinases, G(i) proteins, phosphatidylinositol 3-kinase, p44(erk1) and p42(erk2) mitogen-activated protein kinases, and Jak2 kinases partially attenuated the effect of conditioned medium, consistent with a role for G-CSF and/or GM-CSF. Hence, delayed neutrophil apoptosis is mediated by GM-CSF and G-CSF secreted by T. gondii-infected human fibroblasts. This enhanced neutrophil survival may contribute to the robust proinflammatory response elicited in the T. gondii-infected host.  相似文献   
48.
One thousand and thirty-one singleton children of teenage mothers were compared with 10 950 singleton children of older mothers in a national longitudinal cohort study. Children born to teenage mothers and living with them during the first 5 years were more liable to hospital admissions, especially after accidents and for gastroenteritis, than were children born to and living with older mothers. Frequent accidents, poisoning, burns, and superficial injuries or lacerations were more often reported by teenage mothers. The association of teenage mothering with greater likelihood that children would have accidents or be admitted to hospital remained highly significant even after controlling for social and biological confounding influences. Although in part a marker for adverse socioeconomic circumstances, low maternal age appears to be a health hazard for children.  相似文献   
49.
SUMMARY A 23-year-old man, previously fit and well, presented with an atypical pneumonia, associated with microangiopathic anaemia, thrombocytopenia, rhabdomyolysis and renal impairment. Despite administration of intravenous fluids and antibiotics, his condition rapidly deteriorated, and the possibility of an aggressive connective tissue disorder was raised. Thus he was treated with high-dose oral steroids and plasma exchange until autoantibodies were shown to be negative. At this stage it transpired that the patient had swallowed water from a stream three weeks earlier, and leptospira antibody titres were subsequently found to be elevated. Antibiotics were continued, and after a protracted course he made a full recovery. Leptospirosis should be remembered as a rare cause of atypical pneumonia, particularly if there is associated hepatic or renal impairment.  相似文献   
50.
Two cases of nonmalignant adrenal masses with prolonged T2 relaxation time and increased adrenal/liver signal ratios are reported. These two cases, one a functioning adenoma with small areas of hemorrhage and the other tuberculosis, emphasize that increased signal intensity in an adrenal mass on T2-weighted images is not always due to malignancy or a pheochromocytoma. While the signal characteristics of an adrenal mass are useful in distinguishing malignancy or pheochromocytoma from benign adenomas, other studies (such as computed tomography for the detection of hemorrhage), clinical evaluation, and percutaneous biopsy remain useful in the investigation of an adrenal mass.  相似文献   
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