The ultrastructural characteristics of the arcuate and median eminence in the rat have been studied by means of folmaldehyde-osmic acid fixation method. The observations showed that there are two kinds of neurons (dark and light) in the arcuate nucleus which might be responsible for producing both dopamine and releasing hormones. The tanycytes of the ependyma of the third ventricle run longitudinally through various zones of the median eminence and reach the perivascular space of the portal capillaries. The neurosecretory substance-containing nerve terminals may travel between ependymal cells or end around the basal membrane of the capillaries of the median eminence, even keep close to the endothelial fenestrae of "open-type capillary". The axo-somatie and axo-dendritic synapses are formed at the soma and dendrites of neurons of the arcuate nucleus. Both agranular type and granular type axo-axonic synapses are encountered in the fibrous zone of the median eminence. There are also synaptic connections between the basic processes and the large granular vesicles containing nerve terminals in the palisade zone of the median eminence. The ultrastructural characteristics mentioned above suggest that (1) the releasing (or inhibiting) hormones of the hypothalamus might be released into the portal capillaries from nerve terminals directly or into the cerebro-spinal fluid of the third ventricle and then uptaken by the tanycytes, and transported to the portal capillaries by their processes. (2) each step of synthesis, storage, transport and release of the releasing (or inhibiting) hormones could be regulated by nervous mechanism

The distribution of somatostatin (SRIF) in substantia gelatinosa of the rat spinal cord was studied by means of immuno-electron microscopy. The ultrastructural features showed that nerve terminals containing SRIF take part in forming presynap- tie elements of axe-somatic, axe-dendritic and axo-axonic synapses. The immune- reactive products locatl at the external membrane of mitochondria, around the small clear synaptie vesicles and in the large granular vesicles. Most of synaptic vesicles are round or ovoid in shape. Only a few of them are flattened. Based on the ultrastructural characteristics mentioned above and related experimental results the authors believe that SRIF in substantia gelatinosa of the rat spinal cord is probably involved as a neurotransmitter instead of neuromodulator.

Objective To analysis the risk factors and drug resistance of multidrug-resistant pseudomonas aeruginosa(MDRP) infection and to provide the basis for clinical anti-infective therapy .Methods Predisposing factors and drug resistance to clinical commonly used antibacterial drugs of MDRP which were separated from September 2010 to December 2011 were adopted for retro-spective analysis .Results A total of 235 hospital MDRP infection were collected ,97 multidrug resistant strains were concluded ,the separation rate was 41 .2% .The separation rate of ICU and neurosurgery were higher ,account for 35 .54% and 22 .31% respective-ly .The main resource of specimen is respiratory tract ,about 75 .21% .The resistance of MDRP was very serious .The resistant rate of Amikacin was the lowest ,account for 37 .11% ,followed by piperacillin/tazobactam ,ceftazidime ,account for 47 .4% and 48 .45%respectively .The resistant rate of other antimicrobial agents were greater than 50% .Advanced age ,serious underlying diseases ,long hospital stay ,long-term repeated application of broad-spectrum antimicrobial drugs ,admission to ICU ,invasive treatment operations were the risk factors for MDRP resistance .Conclusion The resistance is very serious ,in order to reduce the generation and spread of drug-resistant strains ,the hospital infection control ,drug resistance monitoring ,rational use of antimicrobial drugs and prevention of cross-infections should be strengthened .

Brain atlas provides a spatial reference system on which other images can be interpreted in a consistent way, and it is essential for the brain imaging research. However, because of the differences in structure between occidental and oriental brains, the brain atlas based on Western populations, e. g., the International Consortium for Brain Mapping's 154 T1 Weighted Average Atlas, may not be appropriate for other ethnic groups. Therefore, in the present study, we produce an average brain atlas which is based on the data collected from 100 healthy Chinese volunteers. The differences in brains between the Chinese population and the Western population were also investigated. Comparatively,Chinese brains are wider and shorter in size, and smaller in volume.
Asian Continental Ancestry Group ; Brain ; anatomy & histology ; physiology ; Brain Mapping ; Female ; Humans ; Imaging, Three-Dimensional ; Magnetic Resonance Imaging ; Male ; Reference Values