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As the data collected in a survey we conducted show, a major part of the modern general practitioner's work continues to be in the field of family medicine. This fact is also confirmed by the results of other surveys of general practice today. Patients still appreciate their GPs as a source of good medical care and counseling for the whole family. Our own study has shown that most patients would even like to see an expansion of the GP's counseling activities. The duration of the doctor-family relationship extends over many years, and is frequently longer than a decade.  相似文献   
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BACKGROUND: The sensitivity of diagnostic imaging of processes in the parotid gland has been increased by improved spatial resolution, yet specificity remains unchanged. The purpose of this study was to determine whether the low-flow color duplex technique alters the specificity of B-mode ultrasonography. PATIENTS AND METHODS: Forty-one patients with tumors of the parotid gland were examined by color duplex echography as well as histologically. Twenty-eight of the 41 patients had benign tumors and 13 had malignant disease. In 17 of 41 patients, color duplex ultrasonography failed to detect any vascularization within the tumor. Histopathological examination showed that 3 of these 17 tumors were malignant and 14 of 17 were benign. Intranodal vascularization was detected in 24 cases. Ten of these patients were found to have malignant tumors of the parotid gland; 14 had benign parotid tumors. RESULTS: Our present findings show that marked intratumoral vascularization especially appears in malignant tumors. In contrast to lymph nodes, the location and texture of intranodal blood vessels do not provide information about the nature of the neoplasm. CONCLUSIONS: Low flow duplex ultrasonography does not increase the specificity of preoperative examination in tumors of the parotid gland.  相似文献   
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In many malignant cells, both the anchorage requirement for survival and the function of the p53 tumor suppressor gene are subverted. These effects are consistent with the hypothesis that survival signals from extracellular matrix (ECM) suppress a p53-regulated cell death pathway. We report that survival signals from fibronectin are transduced by the focal adhesion kinase (FAK). If FAK or the correct ECM is absent, cells enter apoptosis through a p53-dependent pathway activated by protein kinase C lambda/iota and cytosolic phospholipase A2. This pathway is suppressible by dominant-negative p53 and Bcl2 but not CrmA. Upon inactivation of p53, cells survive even if they lack matrix signals or FAK. This is the first report that p53 monitors survival signals from ECM/FAK in anchorage- dependent cells.  相似文献   
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Hematocrits (PCV) were measured at 29 and 106 d of age (PCV1 and PCV2, respectively) in male and female White Plymouth Rocks. Four lines were used, two of which had undergone 40 generations of divergent selection for 8-wk BW (HWS, LWS), and two respective sublines (HWR, LWR), in which selection had been relaxed for five generations. At both ages, males and females did not differ for PCV in lines HWR, LWR, and LWS. For line HWS there was an age by sex interaction that resulted from an age effect for males but not for females, and from a sex effect at each age. At both ages, PCV was higher for the HW than the LW lines. Initially, there was no difference between the selected and their respective relaxed lines, but by 106 d, HWR chickens had a higher PCV than HWS chickens. In lines HWR and LWR, PCV increased with age. There was a negative correlation in HWS males for PCV1 with 28 and 56 d BW. The HWR males also had a negative correlation for PCV1 with BW at 28 d, but not between PCV2 and BW. The correlation for PCV1 with PCV2 was high and positive for HWR males and females.  相似文献   
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A role for GH in the pathogenesis of diabetic retinopathy has long been postulated. Previous clinical studies, however, have been confounded by hyperglycemia. We have identified 2 cases of retinopathy associated with exogenous GH therapy in nondiabetic patients. Cases were identified through the MedWatch drug surveillance system of the U.S. Food and Drug Administration. Causality by concomitant medications was excluded by a search of the literature and the FDA data base. The first patient, an obese, 31-yr-old male with traumatic hypothalamic injury, presented with nonproliferative retinopathy and macular edema, resulting in decreased visual acuity (OD 20/40-1; OS count fingers), which required laser surgery. Human GH had been initiated at 0.009 mg/ kg.day, 14 months earlier, and titrated to 0.017 mg/kg.day. The second patient, a nonobese, 11-yr-old girl receiving GH for the management of short stature in Turner's Syndrome, presented with neovascularization. GH doses were 0.033 mg/kg.day for the first 17 months and 0.043 mg/ kg.day for the following 5 months. Cumulative laboratory and clinical observations suggest that GH and related peptides have a role in retinal pathology independent of the degree of glucose tolerance.  相似文献   
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Glycogen in the placenta and its appendages is important for fetal well-being. The precise location of the glycogen stores, however, is unknown. This study was initiated to quantitate glycogen levels at well-defined sampling sites in more than 641 samples from 10 uncomplicated pregnancies and to correlate these glycogen levels with clinical and morphological variables. By biochemical assay, glycogen levels were greatest in the midumbilical cord section (29.08 +/- 1.18 mg/g dry wt) and lowest in the amnionic membrane (2.31 +/- 0.08 mg/g dry wt). Within the placental disk, parenchymal glycogen levels were greatest near the cord insertion (9.31 +/- 2.68 mg/g dry wt) and lowest at the periphery (5.71 +/- 1.14 mg/g dry wt). The midumbilical cord glycogen level showed strong direct correlations (P < .001) with birth weight, umbilical cord weight, and total calculated umbilical cord glycogen and somewhat lower but significant (P < .037) direct correlations with the calculated mean umbilical cord glycogen level, total calculated placental glycogen content, and placental weight. The glycogen level in the middisk parenchymal section from the fetal surface correlated directly with gestational age. Periodic acid-Schiff stains showed that magenta glycogen granules were most abundant in the cytoplasm of the vascular smooth muscle cells. These data show significant variations in glycogen levels among sampling sites. Definition of the precise sampling site is important for clinicopathologic studies of placental glycogen and for interstudy correlations.  相似文献   
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