激光小角光散射仪测定右旋糖酐分子量

激光小角光散射仪(LALLS)由于采用了激光光源,具有光强度高、单色性强、准直性好等特点,可以在微量样品池及很低浓度的溶液中进行小角度(3°～7°)散射光强的测量,溶质的瑞利系数与其分子量有如下关系:     

A flexible implantable microelectrode array for recording electrocorticography signals from rodents

Biomedical Microdevices - Electrocorticography signals, the intracranial recording of electrical signatures of the brain, are recorded by non-penetrating planar electrode arrays placed on the...     

Intrarater reliability of manual muscle test (Medical Research Council scale) grades in Duchenne's muscular dystrophy.

The purpose of this study was to document the intrarater reliability of manual muscle test (MMT) grades in assessing muscle strength in patients with Duchenne's muscular dystrophy (DMD). Subjects were 102 boys, aged 5 to 15 years, who were participating in a double-blind, multicenter trial to document the effects of prednisone on muscle strength in patients with DMD. Four physical therapists participated in the study. Two identical (duplicate) evaluations were performed within 5 days of each other by the same examiner initially and after 6 and 12 months of treatment. A total of 18 muscle groups were tested on each patient, 16 of them bilaterally, using a modification of the Medical Research Council scale. Reliability of muscle strength grades obtained for individual muscle groups and of individual muscle strength grades was analyzed using Cohen's weighted Kappa. The reliability of grades for individual muscle groups ranged from .65 to .93, with the proximal muscles having the higher reliability values. The reliability of individual muscle strength grades ranged from .80 to .99, with those in the gravity-eliminated range scoring the highest. We conclude the MMT grades are reliable for assessing muscle strength in boys with DMD when consecutive evaluations are performed by the same physical therapist.     

Haemodynamic Studies During the Management of Severe Tetanus

Detailed invasive haemodynamic studies were performed in 27of 32 patients with severe tetanus. Nineteen had severe uncomplicatedtetanus and eight had associated major complications, chieflyinfection and pulmonary complications. The results were comparedwith those obtained from 15 healthy male volunteers who servedas controls. There were two deaths in 32 patients (mortality6.25 per cent). Severe tetanus without major complications wascharacterized by a high output hyperkinetic circulatory statewith tachycardia (heart rate 131 (19.2) beats/minute), increasedstroke volume index (43.1 (10.7) ml/m²), increased cardiac index(5.48 (0.94)1/min/m²) and a normal left ventricular stroke workindex (60.5 (15.9) g/m/m²). Volume loading demonstrated a significanthaemodynamic response and increased vascular capacitance. Evenso the maximum percent rise from baseline values of these indicesafter volume load was significantly higher in controls (p <0.001). Autonomic cardiovascular disturbances affected bothsympathetic and parasympathetic activity. Hypertension and tachycardiaalternating with hypotension and bradycardia were related tosudden fluctuations in systemic vascular resistance. Our studiessuggested some degree of myocardial dysfunction in patientswith severe uncomplicated tetanus. The haemodynamics of severetetanus were masked and altered by complicating infection, pneumonia,and atelectasis.     

Diagnosis of Wilms' tumor using near-infrared Raman spectroscopy

Purpose

Raman spectroscopy has distinguished malignant from normal tissues in several types of cancer. This is the first report of applying Raman spectroscopy to the diagnosis of Wilms' tumor.

Methods

Specimens of normal kidney, Wilms' tumor, xanthogranuloma, nephrogenic rests, and rhabdoid tumor were collected fresh from the operating room. Specimens of Wilms' tumor, normal kidney, and congenital mesoblastic nephroma were retrieved from the cryobank and thawed to room temperature. At least 12 Raman spectra were collected from each tissue sample. Histologic slides of each specimen were reviewed by pediatric pathologists. A computer algorithm based on discriminant function analysis (DFA) classified the Raman spectra of Wilms' tumor and the normal sample.

Results

Four hundred sixty-seven spectra were collected from 41 specimens. Using DFA, Raman spectroscopy differentiated Wilms' tumor from normal with 100% sensitivity and specificity and treated from untreated Wilms' tumor with 100% sensitivity and specificity. Using a DFA model built from cryopreserved specimens but applied to fresh Wilms' and normal samples, the sensitivity and specificity were 93.3% and 90.9%, respectively.

Conclusion

Raman spectroscopy is an accurate technique for differentiating Wilms' tumor from normal kidney and treated from untreated Wilms' tumor. It has potential to diagnose in minutes what currently takes several hours to days.     

Unknown poisoning amongst serving personnel

Background: Poisoning is recognized as an important health problem in many countries of the world. There is incomplete information on poisoning accidents, which is a major problem in developing countries.     

Architectonic analysis of the auditory-related areas of the superior temporal region in human brain

Architecture of auditory areas of the superior temporal region (STR) in the human was analyzed in Nissl-stained material to see whether auditory cortex is organized according to principles that have been described in the rhesus monkey. Based on shared architectonic features, the auditory cortex in human and monkey is organized into three lines: areas in the cortex of the circular sulcus (root), areas on the supratemporal plane (core), and areas on the superior temporal gyrus (belt). The cytoarchitecture of the auditory area changes in a stepwise manner toward the koniocortical area, both from the direction of the temporal polar proisocortex as well as from the caudal temporal cortex. This architectonic dichotomy is consistent with differences in cortical and subcortical connections of STR and may be related to different functions of the rostral and caudal temporal cortices. There are some differences between rhesus monkey and human auditory anatomy. For instance, the koniocortex, root area PaI, and belt area PaA show further differentiation into subareas in the human brain. The relative volume of the core area is larger than that of the belt area in the human, but the reverse is true in the monkey. The functional significance of these differences across species is not known but may relate to speech and language functions.