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61.
62.
J A Kane  S P Kane    S Jain 《Gut》1995,36(1):146-147
Traditional Chinese herbal remedies are widely available in the United Kingdom for the treatment of chronic skin disorders. Their benefits are considerable, but their use is completely unregulated. Two patients are described here who suffered an acute hepatitic illness related to taking traditional Chinese herbs. Both recovered fully. The mixtures that they took included two plant components also contained within the mixture taken by a previously reported patient who suffered fatal hepatic necrosis. These cases high-light the need for greater awareness of both the therapeutic and toxic potential of herbal remedies, as well as greater control of their use.  相似文献   
63.
A case of covered exstrophy without sequestration of a bowel segment is reported. A 4-year-old female presented with dribbling of urine. Treatment to date has been simple excision of the covered membrane with functional closure of the bladder and bilateral posterior iliac osteotomies, with reconstruction of the bladder neck and genitalia to be performed at a later date. The embryogenesis of this rare variant, a review of the reported cases, and management options are discussed. Accepted: 6 November 1997  相似文献   
64.
A 35-item questionnaire, designed to assess the relative importance of various factors to medical students when ranking physical medicine and rehabilitation (PM&R) residency training programs during the Match, was sent to all members of the 1991 senior class after Match Day. This mailing was coordinated with the National Resident Matching Program. The questionnaire was also sent to all PM&R residency training program directors and all physiatrist faculty members at the University of Medicine and Dentistry of New Jersey--New Jersey Medical School (UMDNJ-NJMS). Recipients were asked to grade selection factors based on a numerical scale: 1, extremely important; 2, very important; 3, important; 4, minimally important; 5, not important. A response rate of 41% (73/179) for medical students, 87% (62/71) for residency training directors and 71% (22/31) for UMDNJ-NJMS faculty members was attained. Analysis of the results indicates that, overall, there is no significant difference in ranking of the factors by each of the three groups surveyed. The intergroup responses for one-third of the factors were significantly different. Diversity of the training experience, current house officer satisfaction, it "feels" right and house officer quality were the four most important selection factors to the medical students.  相似文献   
65.
Pancreatic adenocarcinoma can present with a vast spectrum of rare manifestations. It usually occurs after the age of 50 years, the peak incidence being in sixth and seventh decades. We report a previously asymptomatic subject of pancreatic adenocarcinoma who presented for the first time with massive upper gastrointestinal hemorrhage. Endoscopy revealed ruptured esophageal varices which were secondary to tumour-induced thrombosis of the portal vein. Besides the uncommon mode of presentation, the patient was unusual because of his young age. Further, he was non-icteric at the time of presentation and remained so throughout the clinical course despite having a large lesion in the head of the pancreas.  相似文献   
66.
Duplications in the 22q11.2 region can cause 22q11.2 duplication syndrome and encompass a variety of phenotypes including developmental delays, facial abnormalities, cardiovascular defects, central nervous system delays, and other congenital abnormalities. However, the contribution of these contiguous duplicated regions to the clinical phenotypes has not been fully elucidated. In this study, we identified nine patients carrying different 22q11.2 microduplications detected by chromosomal microarray. Of these patients, seven pediatric patients presented with various clinical features including two neonate cases died shortly after birth, and two healthy adults. We examined region specific genotype–phenotype associations and found unpredictability associated with 22q11.2 duplications in these nine patients.  相似文献   
67.
The biological effects of camphorquinone (CQ), an initiator for light-polymerized resins, have been reported to relate to its ability to generate free radicals and cause radical-induced membrane damage via lipid peroxidation. However, the effects of CQ on lipids other than peroxidation may result in unfavorable tissue responses especially at concentrations that are not overtly toxic to cells. The purpose of the current study was to examine the effects of CQ on cell lipid metabolism at subtoxic concentrations, with or without visible light irradiation. HCP and THP-1 cells were exposed to CQ with or without light irradiation under clinically relevant conditions and lipid metabolism was analyzed using 14C-labeling and thin-layer chromatography. We found that CQ increased synthesis of neutral lipids, such as triglycerides, from 7 to nearly 15% of the total and diglycerides from 2% to about 3% of the total in HCP cells, while synthesis of phospholipids, such as sphingomyelin, was decreased by 1-1.5%. In THP-1 cells cholesterol synthesis increased more than 2-fold and cholesterol ester synthesis increased more than 5-fold. Light-activated CQ did not differ significantly in terms of its bioactivity compared to no-light conditions. We conclude that CQ significantly altered the metabolism of several important structural lipids in two cell types at sub-toxic concentrations that are clinically relevant. These changes in lipid metabolism may in turn affect membrane integrity and permeability and possibly lead to significant changes in cell responses.  相似文献   
68.
Rotavirus causes severe morbidity in developed countries and frequent deaths (> or = 500,000 per year) in less-developed countries. Historically, four serotypes--G1, G2, G3, and G4-have predominated; they are distinguished by one of two surface neutralization antigens (VP7). However, in 1983 and 1984 we described a new rotavirus serotype, designated G9, in five children hospitalized for diarrhea in Philadelphia, Pa. G9 rotavirus was not identified again in the Western Hemisphere until it caused ca. 50% of the rotavirus disease detected in Philadelphia in the 1995-1996 season. This outbreak allowed us to question whether a rotavirus strain completely new to a well-studied community would target either very young infants or older children, cause especially severe disease, or completely displace previously extant serotypes. We observed a significant excess of G9 infections in younger infants (especially in those < 6 months old) that might be attributed to the lack of G9-specific antibodies in mothers. Of further note, six of the seven oldest patients with rotavirus diarrhea were infected with the G9 strains (not significant). However, the age distribution of children with rotavirus did not differ over a 5-year study period regardless of the infecting serotype. Patients with diarrhea associated with G9 strains did not have disease more severe than that caused by the G1, G2, or G3 serotype. G9 strains did not displace the other serotypes but were virtually completely replaced by G1 or G2 serotypes in the three subsequent rotavirus seasons. We conclude that the abrupt appearance of this novel rotavirus serotype did not present a special threat to public health in the community.  相似文献   
69.
1. The inhalation of CO(2) produces a tachypnoea only in the presence of intact vagus nerves; the present study was designed to examine the mechanism of this phenomenon in the dog.2. Closed-chest cardiopulmonary bypass was established in dogs weighing 16-24 kg, anaesthetized with chloralose. When the ;bypass' was established pulmonary blood flow ceased, P(A, CO2) was reduced and the respiratory rate slowed. 3-10% CO(2) in O(2) could then be inhaled without change in the level of P(a, CO2) set at the oxygenator.3. The addition of CO(2) in these concentrations to the inspired oxygen resulted in an increase in respiratory frequency, maximal at the first breath and sustained for the 1 min period of exposure. The increase in respiratory frequency was due to a shortening of expiratory duration. Inspiratory duration did not change. The response was absent after vagotomy.4. Inert gases in O(2), given as a control, had no effect on breathing.5. The effect of raising P(a, CO2) (by increasing the concentration of CO(2) in the gas equilibrating the blood in the oxygenator), was primarily to increase tidal volume.6. The ventilatory effect of inspiring CO(2)/O(2) mixtures was shown to be additive to the effect of raising P(a, CO2).7. These experiments show that an afferent vagal reflex originating from the lungs causes tachypnoea, when a dog, on ;bypass', inhales low concentrations of CO(2) in O(2).  相似文献   
70.
There are several points of similarity between the processes of cancer metastasis and inflammation. In both, cells circulate in the vasculature, arrest, and cross vessel walls, thereby entering the extravascular tissues. In vitro, leukocytes and some, but not all, tumor cells exhibit chemotaxis. Since the chemotactic response of leukocytes effect their transvascular migration, we propose that chemotactic responsiveness contributes to the ability of circulating tumor cells to localize in extravascular tissues. This study was done to seek a relationship between chemotactic responsiveness of tumor cells and their behavior in vivo. Two subpopulations of cells were isolated from a methylcholanthrene-induced fibrosarcoma. The two cell lines were compared with regard to their biologic behavior in vivo and their chemotactic responsiveness in vitro. In vivo one subpopulation was highly malignant. An injection of 2.0 x 10(5) cells into the footpad of syngeneic mice led to the development of primary tumors in 87% of the animals and lung metastases in 61% of the animals with primary tumors. This line demonstrated chemotaxis to a factor that behaved similarly in gel filtration and showed immunologic reactivity similar to that of a previously described tumor cell chemotactic factor derived from the fifth component of complement. In contrast, an injection of the same number of cells from the second subpopulation of fibrosarcoma cells led to the development of primary tumors in only 12% of syngeneic mice, and lung metastases did not occur. Neither this subpopulation nor normal embryonic fibroblasts demonstrated chemotactic responsiveness. We postulate that the ability of tumor cells to respond to specific chemotactic stimuli may be one of the many unique properties which distinguish malignant from benign tumor cells. This is the first report documenting the chemotactic responsiveness of non-ascites tumors and fibrosarcomas.  相似文献   
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