We have designed a sort of multi-functional bone forceps for use as orthopedic surgical instruments to grip, bend and cut the spicula. It is labor-saving and easily installed. Its left and right clamp bodies are connected by a rivet to hold the spicula, and the pressure-regulating shank is connected with the clamp seat body at the right top of the clamp body by a rivet. It is used to curve the spicula. At an appropriate location on the pressure-regulating shank is a pin-cutting chip. On the right body rotating disc-clamp, there is a rectangular open cutting groove to be in use for cutting the specula with the role of pin-cutting chip. Being characterized by the use of mechanical leverage, the manipulations of holding and bending are less arduous. After achieving the 90-degree bend, the operator can cut off the specula successfully. The operation is easy to perform and labor-saving; the forceps can further meet the actual clinical demand.
Equipment Design ; Fracture Fixation, Internal ; instrumentation ; Humans ; Surgical Instruments

The afferent projections of the locus coeruleus (LC) were studied in 32 rats following the microelectrophoretic delivery of HRP into the different parts of the LC. It was revealed that the LC received afferent fibers widely from the brain, and some topographic localization may exist. Following the injection of HRP into the rostral part of the LC, HRP labeled neurons were observed widely distributed in the brain and spinal cord. In the telencephalon, moderately HRP labeled neurons were observed in the bed nucleus of the stria terminalis, medial and lateral preoptic area, and a few HRP labeled neurons were observed in the areas 13 and 14 of the insular cortex, areas 8 and 10 of the frontal cortex and the central amygdaloid nucleus. In the diencephalon, numerous labeled neurons were observed in the lateral and dorsal hypothalamic area, and a few labeled neurons were observed in the paraventricular nucleus, ventromedial nucleus and arcuate nucleus of the hypothalamus, the parafascicular nucleus of the thalamus, zona incerta and the lateral habenular nucleus. In the brain stem, cerebellum and spinal cord, numerous labeled neurons were observed in the periventricular gray substances, reticular formation and Vestibular nuclei, and a few labeled neurons were observed in the lateral reticular nucleus, solitary nucleus, prepositus nucleus, nucleus of the Spinal tract of the trigeminal nerve, nucleus raphe magnus, nucleus raphe pontis, nucleus raphe dorsalis, parabrachial nucleus, substantia nigra, nucleus lemnisci lateralis, fastigial nucleus, and spinal cord. However, following the injection of HRP into the caudal part of the LC, labeled neurons were observed only in the brain stem, cerebellum and spinal cord, no HRP labeled neurons were found in the telencephalon and diencephalon.

The divergent axon collaterals from neurons in locus coeruleus have been in vestigated by means of fluorescent double labeling technique in 36 rats.Different fluorescent tracers, Fast Blue, Nuclear Yellow, Propidium iodide, Bisbenzimide, Evans Blue, DAPI and Primuline were injected into the prefrontal cortex, the thalamus, the hippocampus, the cerebellum and cervical cord to observe the double retrograde labeling neurons of the locus coeruleus.Following unilateral or bilateral combined injections of two fluorescent tracers into the thalamus and cerebellum, the hippocampus and cerebellum, the hippocampus and thalamus, the larefrontal cortex and cerebellum, the prefrontal cortex and thalamus, the prefrontal cortex and cervical cord, the hippocampus and cervical cord, the cerebellum and cervical cord, double labeled cells were found in locus coeruleus, and some topographical organizations were also found.

The afferent projections of the prefrontal cortex(PFC) from the cerebral cortex were studied using WGA-HRP technique in 25 rats. The PFC of the rat re- cieved the afferent projections widely arising from the frontal, parietal,temporal, occipital, cingulate, piriform and retrohippocampal cortex. Furthermore,the dif- ferent organizations of the cortical afferent projections of the medial and lateral part of the PFC were also found. Besides the afferents from the somatic and visceral sensory cortex, the PFC of rat also recives afferents of visual and auditory cortex and it appears to be a multiple sensory convergence area.

0.02～0.3?l of 33％ HRP (Sigma Ⅵ) solution in sterile water were injected with a stereotaxic instrument into various sites of the caudate-putamen in 40 rats. The animals were perfused transaortically with 3％ paraformatdehyde and 1％ glutaradehyde in 0.1 M phosphate buffer solution (pH7.4). Frozen sections were dried in a container with P_2O_5 for 2～4 hours and examined for fluorescence in the nucleus nigra. After which, the sections were processed for HRP reaction according to Mesulam's method. A number of cells of substantia nigra were found to show both fluorescence and HRP-positive product, thus confirming the dopaminergic nature of the nigroneostiatum projection.Furthermore, the nigroneostriatum projection was found to be topographically organized, the ventro-medial part of compact zone of the substantia nigra projecting to the dorso-medial caudate-putamen, the dorso-medial part of compact zone to the ventral caudate-putamen, the ventro-middle of compact zone to 1be dorso-lateral and central caudate-putamen, the caudo-lateral part to the central caudate-putamen, the middle part of reticular zone to the lateral and central caudate-putamen, the lateral zone of substantia nigra to the caudal caudate-putamen. Some overlap existed.Strionigral fibers were also topographically organized, which terminated predominantly about the cells of reticular zone. These may form a feedback loop concerning with the modulation of the activity of the dopaminergic neurons in the substantia nigra.

WGA-HRP was injected into different segment of the dorsomedial nucleus (DM) of thalamus by means of microiontophoretical delivery in 19 rats to observe the afferent projections of DM. It is found that the DM received afferent projections widely from the frontal cortex, basal telecephalon, limbic system, monoaminergic neuron, reticular formation, central gray matter and superior colliculus. Furthermore, some topographical organization has also been observed. The medial segment of DM received afferent projections mainly from dorsal agranular insular cortex, infralimbic cortex, amygdaloid complex, septum, bed nucleus of the stria terminalis and raphe nuclei, related with the function of the limbic system. The central segment of DM received afferent projections from the dorsal agranular insular cortex and the prepiriform cortex, also related with the function of the limbic system. The lateral segment of DM received afferent projections mainly from the medial precentral cortex, dorsal division of anterior cingulate cortex, E-W nucleus and superior colliculus, related with the function of eye movement. In addition, all the three segments of DM received numerous afferents from the substantia innominata, nucleus tractus diagonalis (Broca), lateral preoptic area and reticular nucleus of the thalamus.

Using the HRP retrograde tracing method, the projections from the mammillary nucleus to the anterior nuclear complex of the thalamus were studied in the rat. The mamillo- thalamic projections arised from either the medial mammillary nucleus or the lateral mammillary nucleus. The efferent fibers of the lateral part of the medial mammillary nucleus projected mainly to the ipsilateral anteroventral nucleus of the thalamus. The efferent fibers from the medial part as well as the posterior part of the medial mammillary nucleus projected to the ipsilateral anteroventral and anteromedial nucleus of the thalamus. In addition, the projections from the median part of the medial mammillary nucleus to the anteromedial nucleus of the thalamus were also observed. The efferent fibers of the lateral mammillary nucleus projected bilaterally to the anterodorsal nucleus of the thalamus, but more on the ipsilateral side.

WGA-HRP was injected into the dorsomedial nucleus of thalamus (DM)by means of microiontophoretical delivery in 19 rats, and into the dorsal division of anterior cingulate cortex (ACd), the prelimbic area (PL), the dorsal agranular insular area (AId) of prefrontal cortex by using microinjective system in 17 rats to observe the efferent projections of the DM.It was found that the DM projected to a large part of the prefrontal cortex including the medial precentral area (PCm), ACd, PL, AId, ventral agranular insular area (AIv), medial orbital area (MO), ventral orbital area (VO), ventrolateral orbital area (VLO), and some topographical organizations were also found. The lateral segment of DM projects to the ACd, PCm, PL, AId, AIv and VLO. The intermediate segment of DM projects to the AId and AIv. The medial segment of DM projects to the AId, PL, IL, AIv, MO and VO. Furthermore, the DM also projects to some subcortical nuclei, such as the reticular nucleus of thalamus (R), the lateral preoptic area (LPO), the lateral hypothalamic area (LHA), the caudoputamen, the nucleus accumbens and the parafascicular nucleus of thalamus. In addition, some reciprocal connections between the DM and the ACd, PCm, PL, IL, AId, R, LPO and LHA were observed.

The projections of the cerebellar nuclei to the spinal cord were studied in the rat following injections of HRP into the cervical, thoracic, lumbar and sacral cord. Numerous HRP-positive neurons were found in the fastigial nucleus (F) and the posterior interpositus nucleus (IP) on both sides, but more on the contralateral side. In the F labelled neurons were mainly distributed in the ventrolateral and medial part of the middle portion of the nucleus, and considerable amount of labelled cells were found in the bundles of the cerebellar corticovestibular fibers as well. In the IP labelled neurons were seen only in the medial part of the nucleus. In addition, a few labelled cells were also found in the dentate nucleus (D) bilaterally. The present study suggests that the neurons of the F, IP and D project their fibers to C_4, a few fibers may extend caudally to C_8.

The nigrothalamic projections were studied with HRP technique in 40 rats.Theanimals were divided into two groups.In one group HRP was injected into varioussubdivisions of the thalamus to observe the retrograde labelled cells in the reticularzone of substantia nigra(SNR)and in the other group HRP was injected into SNRto observe the anterograde labelled fibers and terminals in the thalamus.The nigrothalamic projections were found to originate mainly from SNR,but afew from the compact zone of substantia nigra(SNC)were also observed.Thefibers originated from all parts of the SNR,but the fibers originating from thecaudal part out number those from the rostral part and the ventral part was foundto predominate over the dorsal part.The nigrothalamic projections mainly terminated in ventral medial nucleus ofthe thalamus,but a few fibers terminating in dorsal medial nucleus,parafascicularisnucleus,ventral anterior nucleus and central lateral nucleus of the thalamus were alsofound.It is essentially similar with the site of termination and distribution ofnigrothalamic fibers in the cat and monkey,but there are some quantitative differ-ences.