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951.
The topographic organization of afferent projections from the deep cerebellar nuclei, medulla oblongata and spinal cord to the paramedian reticular nucleus (PRN) of the cat was studied using the horseradish peroxidase (HRP) method of retrograde labelling. Discrete placements of HRP within each of the dorsal (dPRN) and ventral (vPRN) regions of the PRN showed some segregation of input. The deep cerebellar nuclei project in a predominantly contralateral fashion upon the PRN. A small but significant ipsilateral fastigial afferent component is also present. The fastigial and dentate nuclei contribute the majority of fibers to the dPRN whereas the interposed nucleus provides very little. The vPRN receives a relatively uniform input from all 3 cerebellar nuclei. Both lateral vestibular nuclei contribute the majority of fibers from the vestibular nuclear complex largely from their dorsal division. Additional input arises from bilateral medial and inferior vestibular nuclei. The vPRN receives relatively more fibers from the inferior vestibular nuclei than does the dPRN while inputs from the medial vestibular nuclei are comparably sparse. The PRN receives bilateral projections from the nucleus intercalatus (of Staderini). A significant projection to the contralateral PRN occurs from the ventrolateral subnucleus of the solitary complex and its immediate vicinity. Additional sources of medullary afferent input include the lateral, gigantocellular and magnocellular tegmental fields, the contralateral PRN and the raphe nuclei. Sites of origin of spinal afferents to the dPRN are bilaterally distributed mainly within Rexed's laminae VII and VIII of the cervical cord whereas those to the vPRN are confined largely to the medial portion of the contralateral lamina VI in the C1 segment. A few labelled cells are found in the thoracolumbar cord with those to the vPRN being more caudal. These data provide the neuroanatomical substrate for a better understanding of the functional role of the PRN in mediating cardiovascular responses appropriate to postural changes.  相似文献   
952.
Objectives. To assess the prevalence of activated protein C resistance (APC-R) among healthy subjects and thromboembolic patients and to determine the clinical characteristics associated with APC-R.
Design. A prospective study.
Setting. One academic medical centre.
Subjects. 91 health controls and 126 thromboembolic patients.
Measurements. Patients and control were genotyped for the factor V Leiden (VaQ506) mutation. The anticoagulant response of the patient's plasma to activated protein C was also determined.
Results. The frequency of APC-R was 3.3% among healthy control subjects and 22% among thrombotic patients of whom 18% were heterozygous and 4% were homozygous. The mean age at the first thrombotic event and the severity of thrombotic disease including the proportion of proximal deep vein thrombosis and the frequency of lung embolism were identical among APC-R positive and negative patients. A family history of thromboembolic disease was elicited more frequently in APC-R positive than in APC-R negative patients (57% vs. 22%, P <0.001). The recurrence rate was higher for APCR-R positive patients (57% vs. 34%, P <0.05). The percentage of cases with a factor predisposing to thrombosis was very similar in APC-R positive (57%) and negative (68%) patients.
Conclusions. A familial history of thromboembolic disease and recurrences are significantly more frequent among APC-R positive than APC-R negative patients.  相似文献   
953.
Abstract. In order to study the natural course of venous flow and temperature reaction in the legs after symptomatic first episode of deep vein thrombosis (DVT), 65 patients (57 with proximal DVT) without further thromboembolic complications during the observation period were followed for 1 year by repeated plethysmography (PG) and thermography (TG). Regarding the non-invasive parameters substantial individual variations were observed during the observation period. After 1 year pathologic PG and TG were still demonstrated in 39% (Iμ (95%) = /0.43±0.05/) and 65% (Iμ (95%) = /1.18±0.11/), respectively, of the patients after proximal DVT. Only a minority of the patients were normalized permanently in both PG and TG during the first year. The high frequency of remaining venous obstruction and especially, persistent thermoactivity is notable and may be of clinical importance.  相似文献   
954.
106 sites with probing pocket depths 7 mm or greater from 14 patients were treated with plaque control instruction and 1 episode of root planing. Sites in each patient were either irrigated with 2% chlorhexidine or left as non-irrigated controls. Irrigation immediately followed root planing and was repeated daily, by the patient, for 24 weeks. Clinical measurements were made at 12 and 24 weeks, as were gingival washings for determining the number and % of spirochetes. Results at 24 weeks demonstrated that bleeding scores decreased from 91% to 9%; the % of spirochetes dropped from approximately 9% to less than 1%; probing pocket depths decreased from 7.5 to 4.5 mm, and probing attachment levels gained 1.1 to 1.4 mm. The chlorhexidine irrigated experimental group and the non-irrigated control group did not differ significantly in any of the studied parameters. Thus, daily patient-administered chlorhexidine irrigation of deep pockets did not augment the effects of non-surgical periodontal therapy.  相似文献   
955.
基底静脉的显微外科解剖学   总被引:3,自引:0,他引:3  
在手术显微镜下对17例(34侧)成人脑标本的基底静脉及其属支进行观察。基底静脉主要由大脑前静脉和大脑中深静脉形成;其长度和管径分别为36.43±6.60mm和1.43±0.39mm;在环池内,基底静脉与大脑后动脉、小脑上动脉和滑车神经关系密切;基底静脉主要位于松果体外下方和外方。此外,还对其属支的起源、形成、管径、回流和支数进行了观察。  相似文献   
956.
957.
Candida septicaemia with multidrug resistance is an uncommon event in preterm neonates. We present an extremely low birth weight infant (gestational age of 27 weeks, birth weight of 980 g) who developed congenital Candida parapsilosis septicaemia. Because the fungus was resistant both to amphotericin B and fluconazole, caspofungin was chosen for therapy. The fungus was successfully eradicated without any clinical or laboratory adverse effects.  相似文献   
958.
Jobst D  Kraft K 《Mycoses》2006,49(5):415-420
Patients with unspecific symptoms were sometimes tested for Candida. In case of findings of this yeast-like fungus in their stools they often were labelled with the diagnosis of a "Candida-syndrome". This comprises headache, weakness, flatulence, ravenous appetite for sweets, itching skin and several more unspecific symptoms. All 500 randomly sampled patients in 12 mainly naturopathic practices were asked to take part. In case of participation, they received stool-tubes and questionnaires to be answered during the waiting-time by the patients themselves. We asked for details of lifestyle, diseases and a number of unspecific symptoms. The stool-tubes were sent to a microbiological lab within 24 h after being filled. About one-third of all 308 participants carried Candida albicans in their stools. This finding is regarded as normal. Smoking habits were highly associated to Candida: 45 of the 78 smokers (58%), but only 68 of the 230 (29%) non-smokers were Candida positive, P < 0.0001. Three more results were associated with Candida-positive stools: Candida-vaginitis, allergies against food and allergies in general. Hints of a Candida-syndrome could not be found. The relation with smoking cigarettes is a new result. Associations to Candida-vaginitis and allergies were described before.  相似文献   
959.
Evidence now confirms that noncommunicable chronic diseases can stem from infectious agents. Furthermore, at least 13 of 39 recently described infectious agents induce chronic syndromes. Identifying the relationships can affect health across populations, creating opportunities to reduce the impact of chronic disease by preventing or treating infection. As the concept is progressively accepted, advances in laboratory technology and epidemiology facilitate the detection of noncultivable, novel, and even recognized microbial origins. A spectrum of diverse pathogens and chronic syndromes emerges, with a range of pathways from exposure to chronic illness or disability. Complex systems of changing human behavioral traits superimposed on human, microbial, and environmental factors often determine risk for exposure and chronic outcome. Yet the strength of causal evidence varies widely, and detecting a microbe does not prove causality. Nevertheless, infectious agents likely determine more cancers, immune-mediated syndromes, neurodevelopmental disorders, and other chronic conditions than currently appreciated.  相似文献   
960.
Short-survival and long-survival thymidine radiograms, and methacrylate-embedded tissue from normal and X-irradiated rat embryos were used to delineate the neuroepithelial source of the cerebellum and trace the earliest cell movements. The cerebellar anlage, crescent shaped, is demarcated by two ventricular landmarks, the anterior extension of the tela choroidea of the fourth ventricle and the embryonic cerebellar fissure. The cerebellar tela choroidea extends from the medullary fourth ventricle posteromedially to the lateral recess of the pontine fourth ventricle anterolaterally. The embryonic cerebellar fissure begins caudally as a single midline incision beneath the fused posterior cerebellar primordium, then splits to follow the unfused cerebellar halves, first separating each from the isthmus then from the pons. The cerebellar primordium is divided into three parts. The lateral cerebellar primordium caps the lateral recess of the fourth ventricle; it is contiguous with the pons medially and separated ventrally from the anlage of the cochlear nuclei by the tela choroidea. The subisthmal cerebellar primordium is situated beneath the isthmus, medially lining the isthmus canal. Laterally and posteriorly, it is continuous with the lateral and postisthmal primordia. The postisthmal cerebellar primordium caps the postisthmal recess of the fourth ventricle and extends to the medullary fourth ventricle. As we shall describe later, each of these primordia is a source of different components of the developing cerebellum. Most cells of the superficially located nuclear transitory zone are labeled with 3H-thymidine administered on day E14 but not thereafter. A high proportion of the cells of the deeper cortical transitory zone could still be labeled on day E15. This supports the assumption made earlier that the first is composed of differentiating deep neurons, the second of Purkinje cells. The cells of the nuclear transitory zone originate in the lateral cerebellar primordium near the junction with the tela choroidea prior to the formation of the germinal trigone and migrate in a superficial position medially. Beginning on day E16, the nuclear transitory zone splits into two components. One has transversely oriented cells that seem to be the source of a decussating fiber tract, presumably the hook bundle of Russell. The other is composed of longitudinally oriented cells that apparently contribute fibers to the ipsilateral superior cerebellar peduncle. The translocation of the cells of the nuclear transitory zone from the cerebellar surface to its depth, to form the deep nuclei, and the radial migration of the cells of the cortical transitory zone to the surfa  相似文献   
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