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91.
Cells in culture were exposed to cis-dichlorodiammineplatinum (II) and platinum-uracil blue. No platinum could be demonstrated in an intracellular location morphologically or by electron-probe x-ray analysis in the case of the former compound. However, platinum was readily demonstrated in phagosomes or phagolysosomes after exposure of cells to platinum-uracil blue.  相似文献   
92.
Diconium bromide, 2-(3,4-dichloroanilino)-quinolizinium bromide, a potent antispasmodic in the lower bowel of the dog, was found in the present study to exert gastric acid-antisecretory and antiulcerogenic activities in the rat stomach. These effects were demonstrated by means of short- and long-term pyloric ligation, acetylsalicylic acid (ASA)-induced ulcerogenesis, and cold-and-restraint stress studies. A reduction of gastric acid concentration by the drug was probably responsible for the decrease in the degree of ulceration and hemorrhagic lesion formation. The drug's inhibition of stress hemorrhagic lesions may be related to an effect both on gastric HCl secretion and on the vasculature in the glabdular mucosa. The delay of gastric emptying by diclonium bromide results from its known antispasmodic or smooth-muscle depressant action. The toxicity of diclonium bromide, perorally, was low in rats and overt signs of drug effect were not evident until toxic doses were administered. It is concluded that diclonium bromide may represent a useful non-anticholinergic drug effective in treating both peptic ulcers and spasticity of the colon (irritable-colon syndrome) in man.  相似文献   
93.
To determine whether foreign medical graduates (FMGs) provide a disproportionate and increasing share of primary care in some rural areas, changes in physician distribution in a rural section of upstate New York over a 20-year period (1953-1973) were evaluated by country of medical education and type of practice. A contiguous urban area was examined for comparison. In 1953, FMGs accounted for a higher proportion of primary care physicians in rural areas (11%) than in urban practice (6%) (p less than 0.01). By 1973, this distribution had increased to 26% rural and 14% urban (p less than 0.001). During the two decades, the number of U.S. medical graduates in primary care declined by 15% in the rural areas but increased by 13% in the urban center. The number of primary care FMGs in this same period increased 88% in the rural area. With a 10% decline in (rural) FMGs trained in developed countries, this net increase in FMGs was accounted for by physicians from developing countries. Primary care physicians trained in the U.S. or in developed countries increased more in the urban center, while physicians from developing countries increased more in rural (53%) than urban (47%) practices. Finally, by 1973, rural primary care physicians were more likely than urban primary care physicians to be from developing countries (p less than 0.001).  相似文献   
94.
In our experience, some examples of mouse monoclonal antibodies of anti-B blood group specificity develop a precipitate when stored at 4 degrees C. This poses problems during the preparation of blood grouping reagents containing anti-B, and in the storage and use of such reagents. Here we show that this problem can be circumvented by alteration of the glycan moiety of the secreted immunoglobulin, either by glycosidase treatment of the partially purified immunoglobulin, or by the addition of glycan processing inhibitors to the hybridoma cell cultures. These findings have importance for the manufacture of monoclonal antibodies, and highlight a possible new role for carbohydrate in immunoglobulin interaction and immune complex formation.  相似文献   
95.
The oral and dental abnormalities associated with a distinct variety of severe short-limb dwarfism are described. The patient, a 9-year-old Arab boy, had delayed development and eruption of teeth, severe oligodontia of permanent dentition, hypodontia, microdontia, supplemental incisor, enamel hypoplasia of primary teeth, doubled and abnormal frenal attachments, bifid uvula, hypoplastic maxilla, and malocclusion. Clinical and radiographic examinations revealed asymmetric dysplasia and anaplasia of long bones, craniofacial dysmorphia, prominent forehead, budlike fingers and bulbous toes, dysplastic nails, severe hearing loss, and reduced joint mobility. These features resemble, in general, those characteristic of Grebe chondrodysplasia, an extremely rare ill-defined syndrome that is inherited as an autosomal-recessive disorder.  相似文献   
96.
Lithiation of 5-bromo-2,4-bis(benzyloxy)pyrimidine (3) with n-BuLi at -80 degrees C followed by the addition of diphenyl diselenide or diphenyl disulfide as an electrophile furnished the corresponding 5-(phenylhetera)-2,4-bis(benzyloxy)pyrimidine, which on exposure to trimethylsilyl iodide in CH2-Cl2 at room temperature yielded the 5-(phenylhetera)uracils in 70-75% yield. Similarly, the 6-(phenylhetera)uracils were prepared from 6-bromo-2,4-bis(benzyloxy)pyrimidine (10). 1-[(2-Hydroxyethoxy)methyl]-5-(phenylselenenyl)uracil (PSAU, 18) and 1-(ethoxymethyl)-5-(phenylselenenyl)uracil (17) were synthesized by the electrophilic addition of benzeneselenenyl chloride to the acyclic uracils under basic conditions. These compounds were evaluated for their ability to inhibit dihydrouracil dehydrogenase (DHUDase, E.C. 1.3.1.2), orotate phosphoribosyltransferase (OPRTase, E.C. 2.4.2.10), uridine phosphorylase (UrdPase, E.C. 2.4.2.3), and thymidine phosphorylase (dThdPase, E.C. 2.4.2.4). 5-(Phenylselenenyl)uracil (PSU, 6) and 5-(phenylthio)uracil (PTU, 7) inhibited DHUDase with apparent K(i) values of 4.8 and 5.4 microM, respectively. The corresponding 6-analogues, compounds 13 and 14, demonstrated inhibitory activity against OPRTase. PTU as well as PSU and its riboside, 2'-deoxyriboside, and acyclonucleosides were inhibitors of UrdPase, with PSAU (18) being the most potent with an apparent K(i) value of 3.8 microM. None of the compounds evaluated had any effect on dThdPase. Interestingly, most of the compounds showed modest selective anti-human-immunodeficiency-virus activity in acutely infected primary human lymphocytes.  相似文献   
97.
Transbronchial biopsy has become the procedure of choice for the diagnosis of acute lung rejection after transplantation, but the sensitivity of the technique in this setting remains unknown. In this study, 14 mongrel dogs underwent left lung transplantation, after which triple-drug immunosuppression was given for 5 days and then all immunosuppression was stopped. All animals had clear chest radiographs at this time. Transbronchial biopsy was performed in nine lung regions (two to six pieces of lung tissue were obtained per region, with a mean of 4.3 pieces per region) before the animals were killed 2 to 4 days later, at which time varying degrees of rejection had occurred. Rejection was graded histologically on a scale of 0 to 3 (0 = no rejection, 1 = mild rejection, 2 = moderate rejection, 3 = severe rejection) in each piece of lung tissue obtained at transbronchial biopsy. After the dogs were put to death, the true state of lung rejection was determined by histologic examination of the entire lung. We calculated the sensitivity of transbronchial biopsy with 95% confidence intervals. Five pieces of lung tissue were needed to yield a sensitivity of 92% (82%, 100%) to identify mild rejection in the entire lung with transbronchial biopsy. Three pieces of lung tissue were needed to yield a sensitivity of 92% (84%, 100%) to identify the presence of moderate to severe rejection in the entire lung (that is, rejection that requires pulse therapy) on transbronchial biopsy. These results indicate that three to five pieces of lung tissue that are suitable for diagnostic purposes obtained at transbronchial biopsy are adequate for the diagnosis of acute pulmonary rejection after lung transplantation.  相似文献   
98.
The present study investigated the effects of the cannabinoid receptor agonist CP 55,940 (1-)-cis-3-[2-hydroxy-4-(1,1-dimethylheptyl) phenyl]-trans-4-(3-hydroxypropyl)cyclohexanol) and the cannabinoid receptor antagonist SR 141716A (N-(piperidin-l-yl)-5-(4-chlorophenyl)-1-(2,4-dichlorophenyl)-4-me thyl-1 H-pyrazole-3-carboxamide hydrochloride) on ultrasonic vocalizations, body temperature and activity in 11-13-day-old rat pups. Testing occurred in a 5-min session 30 min following drug administration. CP 55,940 produced a dose-dependent decrease in ultrasonic vocalizations, with a 1000-micrograms/kg dose causing an almost complete inhibition of calls. Doses of 100 and 1000 micrograms/kg of CP 55,940, but not 10 micrograms/kg, caused significant hypothermia in the pups and the 1000 micrograms/kg dose also inhibited activity. The cannabinoid receptor antagonist SR 141716A (20 mg/kg) reversed the effects of 1000 micrograms/kg CP 55,940 on ultrasonic vocalizations and body temperature, but the benzodiazepine receptor antagonist flumazenil (20 mg/kg), the dopamine D1 receptor antagonist SCH 23390 (0.5 mg/kg) and the opioid receptor antagonist naloxone (1 mg/kg) did not. When administered alone, SR 141716A (20 mg/kg) increased pup ultrasonic vocalizations without affecting body temperature or activity. These results indicate that cannabinoids modulate ultrasonic vocalization production in rat pups in a manner that is independent of hypothermia. The increase in ultrasonic vocalizations produced by SR 141716A is one of the first reported behavioural effects of this drug and suggests that the endogenous cannabinoid ligand anandamide may be involved in the regulation of ultrasonic vocalizations.  相似文献   
99.
BACKGROUND: Ewing's sarcoma and primitive neuroectodermal tumour (ES/PNET) are rare, limiting opportunities for therapy studies in adults. Chemotherapy regimens adapted from paediatric studies are often used for adults but concerns about poor outcome and treatment toxicity may adversely affect drug dose intensity. We present our experience using a paediatric protocol at full dose. PATIENTS AND METHODS: Records of 34 patients with ES/PNET who received the IVAD chemotherapy regimens were reviewed. Received drug dose intensity, toxicity and survival data were collected. RESULTS: Received dose intensity in 30 evaluable patients was 0.92 compared to the standard IVAD schedule. Myelosuppression was the major toxicity, 83% of patients experienced grade 4 neutropenia. There was no major renal or cardiac toxicity. In patients without metastases at presentation, five-year overall survival was 63% and progression free survival was 39%. Tumour burden at presentation was statistically significantly associated with survival (P = 0.002). The five-year survival rate of 80% in patients presenting with low volume non metastatic disease was equivalent to published paediatric series. CONCLUSIONS: Although the IVAD chemotherapy regimens are myelotoxic in adults, they can be given safely. We recommend that adults with ES/PNET should be included in current multicentre, multidisciplinary treatment studies directed at children.  相似文献   
100.
A surgeon has many options available to aid in the closure of abdominal wall defects in the elective setting. In the emergent setting, active infection or contamination increases the likelihood of infection of permanent prosthetic material and limits the surgical options. In such settings, we have used absorbable mesh (Dexon) as an adjunct to fascial closure until the acute complications resolve. To evaluate the effectiveness of this technique, we reviewed the outcome of such closures in 26 critically ill patients. Between July 1987 and June 1993, 26 patients were identified who had placement of absorbable mesh as part of an emergent laparotomy at a major urban trauma center. Through a retrospective chart review, the incidence of complications and outcome of the closure were tabulated. Seven patients were initially operated on for trauma. Two of the patients had mesh placement at their initial procedure secondary to fascial loss from trauma. The remainder of the patients hd mesh placement during a subsequent laparotomy for complications related to their initial procedure. Indications for these laparotomies included combinations of wound dehiscence, intra-abdominal abscess, anastomotic disruption, and perforation. Mesh placement in patients with intra-abdominal infection created effectively open abdominal wounds that allowed continued abdominal drainage, but required extensive wound care. Despite the absorbable nature of the mesh and often prolonged hospital stay in these ill patients, none of them required reoperation for dehiscence, recurrence of intra-abdominal abscess, or infection of the mesh.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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