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81.
OBJECTIVE: This study was designed to assess the significance of HIV-related oral lesions in predicting the rate of progression to AIDS. DESIGN: Cohorts were investigated prospectively, and oral examinations were performed by clinicians trained in the diagnosis of oral lesions. SETTING: We studied three existing cohorts of homosexual and bisexual men in San Francisco, California, USA. PARTICIPANTS: Of the HIV-infected men who received standardized oral examinations (n = 791), 603 were eligible for analysis of baseline examinations and 448 for analysis of follow-up examinations. MAIN OUTCOME MEASURES: We determined time from presence of oral lesion at baseline or follow-up examination, or from participant self-reported history of the lesion, to diagnosis of AIDS. RESULTS: Using proportional hazard regression and stratifying by CD4 lymphocyte count at the time of baseline oral examination, we found that the rate of development of AIDS was increased among men with hairy leukoplakia [relative hazard, 1.8; 95% confidence interval (CI), 1.2-2.7], oral candidiasis (relative hazard, 7.3; 95% CI, 3.1-17.3), and both lesions (relative hazard, 3.1; 95% CI, 1.6-6.1) compared with men with normal findings. On follow-up examination, stratifying for CD4 count, the rate of progression to AIDS was similar for those with hairy leukoplakia compared with those with oral candidiasis. The progression rate from oral candidiasis to AIDS was faster from presence on baseline examination than from presence on follow-up examination or from self-reported history of the lesion. CONCLUSION: The presence of oral candidiasis and/or hairy leukoplakia on baseline examination confers independent prognostic information and should be incorporated into HIV-staging schemes.  相似文献   
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Interventional radiologic procedures in the renal transplant   总被引:1,自引:0,他引:1  
Percutaneous interventional procedures can be valuable in the evaluation and treatment of urologic complications of renal transplantation. Thirty-three patients underwent percutaneous procedures, including relief of obstruction by catheter nephrostomy, diagnostic antegrade pyelography with Whitaker testing, aspiration of various fluid collections (lymphocele, hematoma, urinoma, and abscess), and renal artery angioplasty, during a three year period at three institutions, to provide temporizing treatment and anatomic data. Surgical intervention was sometimes avoided, but more often it could be deferred to allow the patient to stabilize prior to surgery. Complications that required surgery occurred in two patients.  相似文献   
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1. The responses of cutaneous mechanoreceptors in feline hairy skin were examined in vivo with systematic variations in the velocity and direction of stimulus motion across the receptive fields (RF). The mechanoreceptor classes studied were guard hair afferents, field afferents, down hair afferents, and slowly adapting type I (SAI) mechanoreceptors. A camel's hair brush, moved by a high-precision motor, provided surface-parallel stimulation at velocities ranging from 0.4 to 100 cm/s. The stimulating device and protocols were similar to those previously used to evaluate human perception, thus allowing direct comparison of the two sets of data. 2. Each mechanoreceptor produced highly reliable mean firing rates with repeated stimulation. All mechanoreceptors showed a growth in evoked activity with increased stimulus velocity. With few exceptions, the relationship between brush velocity and mean firing rate was well described by a power function throughout the range of velocities tested. The exponents of these power functions, reflecting the degree of velocity dependency for each mechanoreceptor, were largest for the field type 1 units (F1) and guard hair type 1 units (G1). 3. The capacity of the mechanoreceptors to discriminate velocity was examined in the context of signal detection theory. For each unit, a velocity discriminability estimate (velocity delta'e) was calculated for responses to 5 versus 10 cm/s brushing and 10 versus 20 cm/s. The G1 and F1 units exhibited the largest velocity delta'e values, which were comparable to human velocity discriminability (d'e) values. Thus these data show the quantitative parallel between the velocity discriminability of G1 and F1 mechanoreceptors and of human perception similarly tested. 4. Most mechanoreceptors generated different response rates with stimuli moving in opposing directions (in the proximal-distal axis of the hindlimb). However, no mechanoreceptor class showed a consistently preferred direction of movement. A directional delta'e value was calculated for each mechanoreceptor at each stimulus velocity. These values were quite variable, even within a single mechanoreceptor class. In general, a mechanoreceptor's directional delta'e value either 1) decreased with increasing velocity or 2) remained constant across velocities. The way in which human directional discriminability varies with stimulus velocity did not parallel the way in which mechanoreceptor's directional delta'e values varied with the same range of stimulus velocities. 5. Some mechanoreceptors were tested with both the standardized brush, which was smaller than most mechanoreceptors' RFs, and a much larger brush, which was at least twice the size of the mechanoreceptors' RFs.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
84.
Neutralizing antibody to Herpes simplex virus type 1 (HSV-1), type 2, and measles virus was measured in the serum of patients with oral cancer, patients with oral leukoplakia, and in control subjects who were smokers and nonsmokers. Significantly higher titers to HSV-1 were found in controls who smoked than in controls who did not smoke. Patients with untreated oral cancer had HSV-1 neutralizing titers similar to those of the controls who smoked, but those with later stage tumors had higher titers than those with earlier stage tumors. In patients who were tumor free after treatment for oral cancer, higher antibody titers to HSV-1 were associated with longer survival times. No association was found between clinical status and antibody to measles virus. The data are consistent with a role for both HSV-1 and smoking in the pathogenesis of oral cancer.  相似文献   
85.
In a prospective controlled randomized trial, patients with advanced ovarian carcinoma (FIGO Stage III or IV) were treated with cis-diamminedichloroplatinum (II), (DDP), alone, DDP and Adriamycin (ADM), or Triethylenethiophosphoramide (ThioTEPA) and methotrexate (MTX). DDP alone produces objective responses in 31% of evaluable patients, ThioTEPA and MTX in 36%. The combination of DDP and ADM produces the best response rate, 80% (.01 less than P less than 0.25). The risk of progression or death is substantially reduced for the two DDP regimens combined when compared with ThioTEPA-MTX (P = .03). Multivariate analysis further suggests the superiority of the two DDP regimens because poorly differentiated tumors and large, greater than 2 cm, residual tumors failed to produce their usual adverse effect on prognosis when patients were treated with the two DDP regimens. Patients with poorly differentiated tumors or tumors of unknown grade treated with platinum or DDP-ADM experienced better survival than similar patients treated with ThioTEPA (P = .01).  相似文献   
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Newborn lungs are particularly susceptible to pathophysiology. Respiratory distress commonly brings infants to the intensive care nursery. Premature birth compromises the infant's ability to respond to early lung dysfunction because of the reduced functional reserve available at younger gestational ages. The respiratory pump consists of respiratory musculature and the chest wall. The respiratory pump is the physiologic "machine" that responds to lung pathology. From gestation onward, components of the pump undergo developmental changes that influence its compensatory ability in the neonate. Careful observation of the synchrony of the chest wall and abdomen during spontaneous breathing efforts assists the caretaker in detecting respiratory compromise and impending respiratory failure. Noninvasive monitoring of respiratory patterns is a valuable tool for the neonatal caregiver, who must understand the developmental changes in the respiratory pump and be able to identify an infant's ineffective responses to lung pathophysiology.  相似文献   
90.
Recent developments in the definitional literature on mental retardation emphasize the need to ground the concept of adaptive behavior in an expanded model of intelligence, which includes practical and social intelligence. Development of a direct measure of practical intelligence might increase the likelihood that an assessment of this domain would be included in the diagnostic process of mental retardation. The current paper reports on the preliminary exploration of the validity and utility of using a videotaped portrayal of everyday tasks, with built-in errors, as a measure of practical intelligence. A correlation of .79 was found between the practical intelligence video score and the Vineland domestic and community sub-domains score in 50 adults with mild and moderate mental retardation. This suggests that the instruments are essentially measuring the same domain of human competence. The unexplained variance may be attributed to the fact that the video measure is more directly measuring cognition.  相似文献   
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