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BACKGROUND: Current Diagnostic and Statistical Manual of Mental Disorders (DSM) classifications describe spectrums of symptoms that define mood and anxiety disorders. These DSM classifications have been applied to primary care populations to establish the frequency of these disorders in primary care. DSM classifications, however, might not adequately describe the underlying or natural groupings of mood and anxiety symptoms in primary care. This study explores common clusters of mood and anxiety symptoms and their severity while exploring the degree of cluster congruency with current DSM classification schemes. We also evaluate how well the groupings derived from these different classifying methods explain differences in patients' health-related quality of life. METHODS: Study design was cross-sectional, using a sample of 1333 adult primary care patients attending a university-based family medicine clinic. We applied cluster analysis to responses on a 15-item instrument measuring symptoms of mood and anxiety and their severity. We used the PRIME-MD to determine the presence of DSM-III-R disorders. The SF-36 Health Survey was used to assess health-related quality of life. RESULTS: Cluster analysis produced four groups of patients different from groupings based on the DSM. These four groups differed from each other on sociodemographic indicators, health-related quality of life, and frequency of DSM disorders. Cluster membership was associated in three of four clusters with a clinically significant and progressive decrease in mental and physical health functioning as measured by the SF-36 Health Survey. This decline was independent of the presence of a DSM diagnosis. CONCLUSIONS: A primary care classification scheme for mood and anxiety symptoms that includes severity appears to provide more useful information than traditional DSM classifications of disorders.  相似文献   
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In recent years many studies have indicated an involvement of inflammatory mechanisms in Alzheimer's disease (AD). Acute-phase proteins such as 1-antichymotrypsin and c-reactive protein, elements of the complement system, and activated microglial and astroglial cells are consistently found in brains of AD patients. Most importantly, also cytokines such as interleukin-6 (IL-6) have been detected in the cortices of AD patients, indicating a local activation of components of the unspecific inflammatory system. Up to now it has remained unclear whether inflammatory mechanisms represent a primary event or only an unspecific reaction to brain tissue damage. Therefore, we investigated whether IL-6 immunoreactivity could be found in plaques prior to the onset of neuritic changes, or whether the presence of this cytokine is restricted to later stages of plaque pathology. we confirmed our previous observation that IL-6 is detectable in a significant proportion of plaques in the brains of demented patients. In AD patients IL-6 was found in diffuse plaques in a significant higher ratio as would have been expected from a random distribution of IL-6 among all plaque types. This observation suggests that IL-6 may precede neuritic changes, and that immunological mechanism may be involved both in the transformation from diffuse to neuritic plaques in AD and in the development of dementia.  相似文献   
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Summary To prove whether a cell-mediated mechanism is responsible for maintaining long-term normoglycaemia in BB/OK rats with a proved immune attack (insulitis, reduced Beta-cell volume), we transferred lymphocytes obtained from those rats into normoglycaemic diabetes-prone BB/OK rats or into diabetic BB/OK rats receiving a simultaneous syngeneic islet graft. Our results show the presence of a lymphocyte population in the long-term normoglycaemic BB/OK rats, which is able to arrest pancreatic Beta-cell destruction in diabetes-prone BB/OK rats detected by a decreased diabetes incidence following single lymphocyte transfusion. Syngeneic islets were destroyed by recurrence of the autoimmune process when transplanted into diabetic BB/OK rats. Lymphocytes obtained from long-term normoglycaemic BB/OK rats were able to protect the syngeneic BB/OK islet graft from autoimmune destruction in diabetic BB/OK rats, whereas allogeneic islet destruction was not prevented. The phenotype of the effective lymphocyte population is not yet clear, but it is negative for RT6. We conclude that the mechanism responsible for maintaining normoglycaemia in long-term normoglycaemic BB/OK rats is cell mediated, because this property can be transferred to prevent autoimmune destruction of pancreatic Beta cells.  相似文献   
35.
Summary Melanosomes and isolated melanosomal fragments (melanin particles) originating from gangliocytes (substantia nigra), astroglia (melanosis cerebelli), and melanocytes (melanotic meningeoma; metastases of melanoblastoma; melanosis thalami of the goat) were compared with synthetic melanins prepared from dopamine and serotonin, respectively. Samples were examined by electron microscopy, X-ray diffraction analysis according to Debye-Scherrer and by infrared spectrophotometry, and the results were evaluated with regard to characteristic features as they may relate to specific cell types or chemical structures.On electron microscopy all three types of melanosomes could be differentiated unequivocally as could the two synthetic melanins. Thus, there were similarities between synthetic melanin from dopamine and the gliogenic melanins of the cerebellum; the synthetic melanin from serotonin resembled melanin of melanocytes.X-ray diffraction analysis yielded 2-4 Debye diffraction rings with all human and synthetic samples, suggesting short range orders between 3.8 to 5 Å the sample obtained from a goat with thalamic melanosis showed a specific reflex pattern. While diffraction patterns of some melanins were partially identical, in particular that of melanin from dopamine and melanin of substantia nigra and dentate nucleus, respectively, they were different for the various melanocytic melanins. Further investigations are required to determine whether these differences are due to disparities in basic chemical structures or conformations or else, to particular compositional features of the various types of melanocytes as they arise from benign or malignant tumors or a specific species.Infrared spectrophotometry at higher wave numbers revealed the well known patterns of melanins, which are not, however, very suitable, for their further differentiation. At lower wave numbers (fingerprinting) melanin of substantia nigra and the glial melanin in melanosis cerebelli yielded additional absorption bands of identical configuration. In contrast to melanin from dopamine, melanin from serotonin exhibited a closely similar absorption pattern in this spectral range, suggesting that the neuroectodermal melanins may contain a component possibly arising from serotonin.
Herrn Prof. Dr. Wilhelm Doerr zum 25. 8. 1979  相似文献   
36.
BACKGROUND AND OBJECTIVE: Mucosa intact laser tonsillar ablation is an alternative to conventional tonsillectomy. The efficacy of this procedure was demonstrated in canines, but establishing the safety of irradiating human tonsils is paramount. STUDY DESIGN/MATERIALS AND METHODS: An optical-thermal simulation of tonsillar tissue irradiation was previously developed, but the effect of varying parameters was not investigated. The tissue response to irradiation at 5-25 watts for 1 minute and 10 watts for 10 seconds to 162 seconds is simulated. RESULTS: At 15 watts and greater, the peak temperature is over 100 degrees C and the mucosal temperature is over 70 degrees C. At the depth of the tonsil, the temperature does not vary significantly. The peak temperature is at 1 mm. The radial temperature profile is not significantly altered by longer irradiation times. CONCLUSIONS: The optimal dosimetry parameters for irradiation of human tonsillar tissue at 805 nm with the MILTA technique is under 15 watts for approximately 1 minute.  相似文献   
37.
Second primary cancers in breast cancer patients in Slovenia   总被引:8,自引:1,他引:8  
Data from the Cancer Registry of Slovenia were used in a cohort studyto determine whether the incidence of second primary cancers in patients withfirst primary breast cancer differs from the incidence expected in thegeneral population. Special interest was given to long-term survivors. Theexpected numbers of second primary cancers were calculated by multiplying thenumber of appropriate person-years at risk by the corresponding age-andcalendar-period-specific cancer incidence rates for women in Slovenia. Therisk of a second primary cancer was expressed as the standardized incidenceratio (SIR). Of the 8,917 patients newly diagnosed in the period 1961-85 andfollowed-up to the end of 1994, 547 (6.2 percent) developed second primarycancers, whereas 410 (4.7 percent) were expected (SIR = 1.3, 95 percentconfidence interval [CI] = 1.2-1.4). The risk was higher among youngerpatients. In long-term survivors, the risk was increased significantly forsecond primary cancer of th e breast (SIR = 1.4, CI = 1.1-1.7), lung cancer(SIR = 1.6, CI = 1.1-2.3), melanoma (SIR = 2.7, CI = 1.5-4.4) andnon-melanoma skin cancers (SIR = 2.0, CI = 1.6-2.4), corpus uteri cancer (SIR= 1.6, CI = 1.2-2.1), ovarian cancer (SIR = 2.3, CI = 1.7-3.0), and thyroidcancer (SIR = 2.5, CI = 1.2-4.6). Our results confirm the findings of severalcohort studies carried out in Europe, the United States, and Japan,indicating that breast cancer patients should be monitored carefully for theoccurrence of second primary cancers.  相似文献   
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The circle system has been in use for more than a 100 years, whereas the first clinical application of an anaesthetic reflector was reported just 15 years ago. Its functional basis relies on molecular sieves such as zeolite crystals or activated carbon. In a circle system, the breathing gas is rebreathed after carbon dioxide absorption; a reflector on the other hand specifically retains the anaesthetic during expiration and resupplies it during the next inspiration. Reflection systems can be used in conjunction with intensive care ventilators and do not need the permanent presence of trained qualified staff. Because of easy handling and better ventilatory capabilities of intensive care ventilators, reflection systems facilitate the routine use of volatile anaesthetics in intensive care units. Until now, there are three reflection systems commercially available: the established AnaConDa? (Sedana Medical, Uppsala, Sweden), the new smaller AnaConDa-S?, and the Mirus? (Pall Medical, Dreieich, Germany). The AnaConDa consists only of a reflector which is connected to a syringe pump for infusion of liquid sevoflurane or isoflurane. The Mirus represents a technical advancement; its control unit includes a gas and ventilation monitor as well as a gas dispensing unit. The functionality, specific features, advantages and disadvantages of both systems are discussed in the text.  相似文献   
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