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81.
AIM: Assessment of the antihypertensive effect of doxazosin, alpha-1 blocker, as well as its action on lipid and carbohydrate metabolism, microcirculation and platelet function in patients with non-insulin-dependent diabetes mellitus (NIDDM). MATERIALS AND METHODS: Doxazosin (tonocardin) treatment was given for 11 weeks to 33 NIDDM patients with concomitant hypertension. The clinical examination comprised evaluation of central hemodynamics, vessels of the fundus of eye, lipid and carbohydrate metabolism, renal function, platelet aggregation. RESULTS: Tonocardin produced a fall in the systolic blood pressure (BP) by 14%, in the diastolic BP--by 17%. The 24-h profile of BP, lipid and purine metabolism, microcirculation of the vessels of the fundus of eye also improved. Total peripheral vascular resistance, left ventricular myocardial mass and platelet aggregation. Carbohydrate metabolism remained unchanged. CONCLUSION: Monotherapy with tonocardin (2-8 mg/day) is effective and safe in the treatment of arterial hypertension in NIDDM patients.  相似文献   
82.
Current diagnostic criteria for Alcohol Related Dementia (ARD) are based almost exclusively on clinical judgment. Moreover, there are no guidelines available to assist the clinician or the researcher in distinguishing Alcohol Related Dementia from other causes of dementia such as Alzheimer's Disease (AD). However, this distinction may have implications for the prognosis and treatment of patients. In this article, provisional diagnostic criteria for establishing a diagnosis of Alcohol Related Dementia are proposed for further study. The criteria are based on the available literature on the relationship between alcohol consumption and dementia and were modeled after existing diagnostic criteria for AD and Vascular Dementia. Validity of these criteria for distinguishing AD from ARD will require further study.  相似文献   
83.
A combined one stage anterior and posterior approach was used to excise a giant cell tumor involving the second lumbar vertebra. The tumor involved the anterior and posterior elements of the vertebra. A wide excision was feasible with immediate stabilization using the Luque instrumentation posteriorly and fibular strut grafts supporting the vertebral bodies anteriorly. The followup period was 13 years. There is no recurrence, and the patient has no symptoms of disease, and the fibular grafts are fully incorporated.  相似文献   
84.
Spina bifida, a congenital deformity of the posterior wall of vertebrae of the spine, is a midline defect of skin, vertebral arches and neural tube, usually in the lumbosacral region. Its incidence is reported to be 0.2 to 0.4 per 1000 live births. Various hypotheses have been put forward as etiological factors for spina bifida including consumption of potato affected by blight and hardness of drinking water but these have not been proven. Two groups of 50 randomly chosen children were established. The study group consisted of children aged 5 to 12 years, weighing 15 to 30 kg, consuming fluoride rich drinking water (4.5 and 8.5 ppm fluoride; WHO permissible limit is 1.5 ppm fluoride), and manifesting either clinical, dental and/or skeletal fluorosis. The control group consisted of age and weight-matched children, consuming less than or equal to 1.5 ppm fluoride in drinking water and not showing any evidence of fluoride toxicity. These children were evaluated for antenatal history, general clinical examination (especially for dimples, tufts of hair, haemangioma on skin throughout the length of spine), other congenital abnormalities, evidence of fluoride toxicity, biochemical estimation for fluoride levels in blood and serum and by skiagrams of the spine to examine for the presence of spina bifida occulta. A total of 22 (44%) of the 50 children in group A, the study group, and 6 (12%) of the 50 children in group B, the control group, revealed spina bifida occulta in the lumbosacral region.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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86.
The purpose of this study was to develop an examination method to select children without from children with need of dental treatment. Furthermore the objective was that these examinations could be performed as a survey at school, without utilizing an expensive and fully equipped dental clinic but still maintain the certainty for the individual not to be at increased risk to be declared false caries-free, in comparison with ordinary examination at a dental clinic. The material comprised 88 children 10-13 years old. The children were subject to a survey-examination at school and a few weeks later at a dental clinic by the same examiner. Initially the children were examined at school by two examiners in order to measure the inter-examiner variability. The results showed that 2 of the 88 examined children (2.3%) were judged false healthy at school examination with respect to caries. The inter-examiner variability in diagnosing caries was greater than the intra-examiner variability between survey at school and examination at the dental clinic.  相似文献   
87.
Results of eight multicenter, randomized, placebo-controlled, double-blind, parallel-group studies were pooled to assess the efficacy of the angiotensin II-receptor blocker irbesartan over the dose range of 1 to 900 mg. A total of 2955 adults with a seated diastolic blood pressure of 95 to 110 mm Hg were randomized to treatment with oral irbesartan once daily or placebo for 6 to 8 weeks. Office blood pressure was measured at trough (24+/-3 hours after the last dose) and peak (3+/-1 hours after the last dose) by mercury sphygmomanometry. Demographic characteristics (mean blood pressure; 151/101 mm Hg; mean age, 54 years; 63% male; and 82% white) were similar across all dose groups. After the groups were pooled, antihypertensive efficacy was assessed by therapeutic response (trough seated diastolic blood pressure <90 mm Hg or a reduction from baseline of > or = 10 mm Hg) and by modeling of the maximum reductions in trough and peak seated diastolic and systolic blood pressure. Antihypertensive effects increased with increasing doses and reached a plateau at > or = 300 mg. Irbesartan 150 mg provided placebo-subtracted reductions in trough seated systolic and diastolic blood pressure of approximately 8 and approximately 5 mm Hg, respectively, with 56% of patients displaying a favorable response. In conclusion, irbesartan provides clinically significant blood pressure lowering, with a clear relationship between (log) dose and antihypertensive effect.  相似文献   
88.
89.
BACKGROUND: Bluetongue virus (BTV), which belongs to the Reoviridae family and orbivirus genus, is a non-enveloped, icosahedral, double-stranded RNA virus. Several protein layers enclose its genome; upon cell entry the outer layer is stripped away leaving a core, the surface of which is composed of VP7. The structure of the trimeric VP7 molecule has previously been determined using X-ray crystallography. The articulated VP7 subunit consists of two domains, one which is largely alpha-helical and the other, smaller domain, is a beta barrel with jelly-roll topology. The relative orientations of these two domains vary in different crystal forms. The structure of VP7 and the organizations of 780 subunits of this molecule in the core of virus is central to the assembly and function of BTV. RESULTS: A 23 A resolution map of the core, determined using electron cryomicroscopy (cryoEM) data, reveals that the 260 trimers of VP7 are organized on a rather precise T = 13 laevo icosahedral lattice, in accordance with the theory of quasi-equivalence. The VP7 layer occupies a shell that is between 260 A and 345 A from the centre of the core. Below this radius (230-260 A) lies the T = 1 layer of 120 molecules of VP3. By fitting the X-ray structure of an individual VP7 trimer onto the cryoEM BTV core structure, we have generated an atomic model of the VP7 layer of BTV. This demonstrates that one of the molecular structures seen in crystals of the isolated VP7 corresponds to the in vivo conformation of the molecule in the core. CONCLUSIONS: The beta-barrel domains of VP7 are external to the core and interact with protein in the outer layer of the mature virion. The lower, alpha-helical domains of VP7 interact with VP3 molecules which form the inner layer of the BTV core. Adjacent VP7 trimer-trimer interactions in the T = 13 layer are mediated principally through well-defined regions in the broader lower domains, to form a structure that conforms well with that expected from the theory of quasi-equivalence with no significant conformational changes within the individual trimers. The VP3 layer determines the particle size and forms a rather smooth surface upon which the two-dimensional lattice of VP7 trimers is laid down.  相似文献   
90.
Recent advances in head injury research have produced a plethora of useful data coupled with a paucity of conceptual integration across the four ways in which this research is pursued. These research orientations are the epidemiological, biomechanical, basic neuroscientific, and clinicopathologic/therapeutic (including rehabilitation). This overview of the history and current state of the art assumes that biomechanics is the basic science of causation in head injury research and when fully integrated with its counterparts, physiology and pathology, it can serve to overcome our conceptual handicaps. A paradigm integrating biomechanics; into the sequence of preventive, protective, acute therapeutic, and rehabilitative interventions will be described as the concept of preventive management. From this we derive the hypothesized claim that the exact biomechanics and the physiopathologic response at the time of injury (at the macroscopic and microscopic levels) determine the sequence of so-called secondary effects that are conceived as the inexorable delayed manifestations of the primary events and concomitant boundary conditions. Knowledge of these events will enable accurate predictions of the natural history and outcome of head injuries from observations carried out in the early acute phase. Examples to test this claim will be given with particular reference to the two types of traumatic brain injury (TBI) phenomenologically associated with disturbances of consciousness, the onset of which can be either immediate or delayed. The current economics and availability of computational power provide a significant opportunity for the development of selected experimental, physical, and simulated models of head injury on the basis of which the complex neurovascular and nonneural cellular and fluid elements of the nervous system may be accurately modeled. This approach will significantly improve the efficiency and quality of the essential biological and clinical observations and model experiments required to validate the theoretical methods and their predictions.  相似文献   
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