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31.
Intravenous phenytoin has come under increased scrutiny with the introduction of the prodrug, fosphenytoin. We evaluated adverse events and length-of-stay using parenteral the two drugs in routine emergency department use. Open-label randomization of phenytoin or fosphenytoin in 256 Emergency Department patients prescribed 279 parenteral doses of a phenytoin-equivalent. All phenytoin was administered intravenously, and fosphenytoin was given intravenously or intramuscularly (physician preference). Adverse events and Emergency Department length-of-stay were recorded; re-presentation to the Emergency Department within three months was reviewed for evidence of the purple glove syndrome. Nonparametric statistics were used to analyze the data. Seventy-seven patients received phenytoin and 202 fosphenytoin; 28 (10.0%) received intramuscular fosphenytoin. The mean phenytoin-equivalent dose was similar between the groups. Eighteen patients required reduction in infusion rates because of an adverse event (phenytoin = 6.5%, fosphenytoin = 6.4%; OR 0.9, 95% CI 0.4 2.6; p = 1.0). Adverse events occurred with similar frequency (phenytoin 9.1%, fosphenytoin 15.8%; OR 0.7, 95% CI 0.3 1.4; p = 0.3). The most common events were: pruritis, pain on infusion, and paresthesias. One patient developed hypotension (fosphenytoin); there were no other serious adverse events, including phlebitis. Median Emergency Department length-of-stay was 6.7 h for phenytoin and 5.7 h for fosphenytoin (p = 0.6). In routine Emergency Department use, our data do not support formulary conversion from phenytoin to fosphenytoin, based on the incidence of adverse events or Emergency Department length-of-stay.  相似文献   
32.
Successful treatment of an infant with chylous ascites secondary to "congenital leaky lymphatics" is described, followed by a literature review of cases of pediatric chylous ascites. The infant was placed on home total parenteral nutrition for 10 weeks, during which time the chylous ascites resolved and did not recur with the introduction of a normal diet. Forty cases of pediatric chylous ascites have been reported since 1960, with an age range from birth to 18 years. The presenting signs and symptoms were secondary to abdominal distension in over 80% of cases. The chylous ascites was secondary to trauma, which included child abuse (19%), obstruction (27%), or lymphatic abnormalities (54%). Most studies described were not helpful in making the diagnosis, except for lymphangiography and exploratory laparotomy. Many patients were treated with a high-protein, low-fat diet, with or without medium-chain triglycerides, with variable success. Total parenteral nutrition (TPN) was the primary therapeutic modality in five patients, and in all but one of the cases there was complete resolution of the chylous ascites over 3 to 10 weeks with no significant side effects. Total parenteral nutrition, including home TPN, is a safe and effective therapeutic modality for some cases of chylous ascites.  相似文献   
33.
OBJECTIVES: This study sought to determine adherence of physicians to tuberculosis (TB) screening guidelines among foreign-born persons living in the United States who were applying for permanent residency. METHODS: Medical forms of applicants from 5 geographic areas were reviewed, along with information from a national physician database on attending physicians. Applicant and corresponding physician characteristics were compared among those who were and were not correctly screened. RESULTS: Of 5739 applicants eligible for screening via tuberculin skin test, 75% were appropriately screened. Except in San Diego, where 11% of the applicants received no screening, most of the inappropriate screening resulted from the use of chest x-rays as the initial screening tool. CONCLUSIONS: Focused physician education and periodic monitoring of adherence to screening guidelines are warranted.  相似文献   
34.
35.
Osteoblast phenotypic expression in monolayer culture depends on surface microtopography. Here we tested the hypothesis that mineralized bone nodule formation in response to osteotropic agents such as bone morphogenetic protein-2 (BMP-2) and dexamethasone is also influenced by surface microtopography. Fetal rat calvarial (FRC) cells were cultured on Ti implant materials (PT [pretreated], Ra = 0.6 microm; SLA [course grit blasted and acid etched], Ra = 4.0 microm; TPS [Ti plasma sprayed], Ra = 5.2 microm) in the presence of either BMP-2 (20 ng/ml) or 10(-8) M dexamethasone (Dex). At 14 days post-confluence, a homogenous layer of cells covered the surfaces, and stacks of cells that appeared to be nodules emerging from the culture surface were present in some areas on all three Ti surfaces. Cell proliferation decreased while alkaline phosphatase specific activity (ALPase) and nodule number generally increased with increasing surface roughness in both control and treated cultures. There was no difference in cell number between the control and Dex-treated cultures for a particular surface, but BMP-2 significantly reduced cell number compared with control or Dex-treated cultures. Treatment with Dex or BMP-2 further increased ALPase on all surfaces except for PT cultures with Dex. Dex had no effect on nodule area in cultures grown on PT or SLA disks, yet increased nodule number by more than 100% in cultures on PT disks. Though the effect of BMP-2 on nodule number was the same as Dex, BMP-2 increased nodule area on all surfaces except TPS, where area was decreased. Ca and P content of the cell layers in control cultures did not vary with surface roughness. However, cultures treated with Dex had increased Ca content on all surfaces, but the greatest increase was seen on SLA and TPS. BMP-2 increased Ca content in cultures on all surfaces, with the greatest increase on the PT surface. BMP-2 treatment increased P content on all surfaces, whereas Dex only increased P on rough surfaces. Of all cultures examined, the Ca/P weight ratio was 2:1 only on rough surfaces with BMP-2, indicating the presence of bone-like apatite. This was further validated by Fourier transform infrared (FTIR) imaging showing a close association between mineral and matrix on TPS and SLA surfaces with BMP-2-treated cells, and individual spectra indicated the presence of an apatitic mineral phase comparable to bone. In contrast, mineral on the smooth surface of BMP-2-treated cultures and on all surfaces where cultures were treated with Dex was not associated with the matrix and the spectra, not typical of bone apatite, implying dystrophic mineralization. This demonstrates that interactions between growth factor or hormone and surface microtopography can modulate bone cell differentiation and mineralization.  相似文献   
36.
Fourteen consecutive clinically definite relapsing-remitting multiple sclerosis (MS) patients were treated with monthly intravenous cyclophosphomide (CTX) for 6 months. All had experienced severe dinical deterioration during the 12 months prior to treatment with CTX despite treatment with conventional immunomodulating agents and intravenous methylprednisolone. Treatment with CTX led to improvement and neurologic stability within 6 months which was sustained for at least 18 months after the onset of treatment with CTX. Therapy with CTX was well tolerated. CTX may be of benefit in MS patients who experience rapid clinical worsening and are resistant to conventional therapy.  相似文献   
37.
This retrospective review of seven patients with completely obstructing cancers of the left half of the colon, in addition to other reports in the literature, suggests that subtotal colectomy with primary ileal
1 Clinical data on seven patients who underwent subtotal colectomy for obstructing carcinoma of the left colon: 1975–1982.
PatientAge (yr) and SexTumor LocationHospital StayComments
168, FDecending10 daysA and W 40 mo postop1
271, FSigmoid22 daysA and W 18 mo postop
373, FSigmoidA and W 5 yr postop
466, FDecending8 moDead from complications
572, MSigmoid11 daysIncidental cecal cancer; A and W 3 mo postop
666, MSigmoid28 daysAlive with metastasis 16 mo postop
778, MLeft transvers34 daysMany other polyps; A and W 9 mo postop
1
A and W = alive and well.
proctostomy may be the treatment of choice for those lesions that are technically resectable and located high enough to permit an intraperitoneal ileal proctostomy. The morbidity and mortality is less than that seen with the staged approach and the length of hospitalization is shorter. By eliminating a second or third hospitalization and a temporary colostomy, palliation is better in those patients who ultimately die from recurrent cancer. Furthermore, those patients resected for cure may have increased rates of long-term survival.  相似文献   
38.
Metastasis of unknown origin   总被引:1,自引:0,他引:1  
Metastasis of unknown origin (MUO) constitutes between 5% and 10% of all noncutaneous cancers. An MUO is defined as a metastatic tumor for which the site of origin is not suggested by thorough history, physical examination, chest x-ray studies, routine blood and urine studies, and histologic evaluation. Two major groups of MUO can be defined: MUO to lymph nodes only (N1-3), and MUO to visceral sites. The prognosis may be quite good for patients with MUO limited to lymph nodes in the mid to high cervical, axillary, and groin areas. However, MUO in other lymph node areas is far more serious, with the possible exception of that in patients with a new syndrome, i.e., "advanced poorly differentiated carcinoma of unknown primary origin." There is some suggestion that these patients may respond to cisplatin-based combination chemotherapy. Patients with MUO to visceral sites have a poor prognosis. However, metastases from some primary tumors are sensitive to chemotherapy and a limited search for these tumors should be undertaken. These tumors include leukemia-lymphoma, germ cell tumors, small cell carcinoma of the lung, adenocarcinomas of the breast, ovary, endometrium, thyroid, or prostate, and possibly adrenal carcinoma. We start by reviewing the biochemical events of metastasis that may be targets for therapy. The importance of a correct tissue diagnosis is then considered, including the role of standard histochemistry, electron microscopy, enzyme histochemistry, and immunohistochemistry. The relatively limited value of radiologic tests in localizing the primary site of origin of the tumor is emphasized, as well as the limited role of currently available biomarkers. We conclude by discussing the treatment of each of the subtypes of MUO.  相似文献   
39.
Previous studies have shown good clinical results following anterior transposition of the ulnar nerve for compression neuropathy. However, no studies have examined all patients pre- and post-operatively with both clinical and electrophysiological studies to determine if a correlation exists. Twenty-three of 24 (96%) anterior transpositions performed consecutively over 6 years were followed up at a mean of 33.2 months with clinical and electrophysiological examinations. All patients were male "blue-collar" workers with a mean age of 52.1 years. The mean duration of preoperative symptoms was 11.3 months. Preoperatively, 30% were graded moderate and 70% severe. The motor conduction velocity (MCV) across the elbow and electromyography (EMG) correlated with the severity of the clinical findings. Postoperatively, 70% of patients improved, with 40% having a good result and 30% fair, and the MCV improved to a highly significant degree (P less than 0.0005). Thirty percent had a poor result with no clinical improvement, yet the MCV improved to a significant degree (P less than 0.05). There was no correlation between the clinical result and the distal motor or sensory latencies, MCV below the elbow, or EMG. Advanced age, duration of preoperative symptoms, diabetes, hypertension, alcoholism, etiology, type of transposition, tourniquet time, and atrophy did not correlate with a poor result, either clinically or electrophysiologically. Severe clinical findings confirmed by electrophysiological studies do not contraindicate surgery and have a reasonable success rate. In conclusion, preoperative electrophysiological studies correlate with the clinical findings but postoperative ones do not, including the MCV. The MCV improves after anterior transposition of the ulnar nerve regardless of the clinical outcome.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
40.
This study compared silver penetration in the adhesive interface among four versions of adhesives from the same manufacturer: OptiBond FL, OptiBond Solo Plus, OptiBond Solo Plus Dual Cure, and OptiBond Solo Plus Self-Etch, when coupled with dual-cured composite, CoreRestore 2 (Kerr). Twenty flat dentin surfaces were prepared using one of the adhesives and bonded with the composite, following the manufacturer's instructions. The surfaces were sectioned into 2-mm slabs and immersed in ammoniacal silver nitrate for 24 hours. Each specimen was exposed to a photodeveloping solution for eight hours and examined with a scanning electron microscope (SEM). The water permeable area occupied by the silver nitrate tracer was determined, and the relative weight of silver was analyzed by wavelength dispersive spectrometry (WDS). The OptiBond FL group had a significantly lower silver content than the other groups (p < 0.0001). Each group demonstrated different patterns of silver deposition within the adhesive layer and within various features of artifactual fracture from dehydration stress of the SEM. This may be indicative of weak links in the bonded interfaces. Simplified-step adhesives showed increased permeability, which can lead to disruption of coupling with composites.  相似文献   
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