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951.
We studied 17 patients with atherosclerotic bilateral occlusion of vertebral arteries (VA) identified by angiography. Seven had vertebrobasilar TIAs, eight a brainstem stroke (severe in two), and two had only carotid symptoms. Brainstem strokes were more frequent with bilateral intracranial occlusion (60%) than with at least one extracranial occlusion (28.6%), but long-term prognosis did not differ in these two groups. In follow-up, the mortality rate was 4.5% per year, and the stroke rate was 1.8% per year. Major functional disability was seen in 16.7% of the survivors. Bilateral distal VA occlusion may sometimes have a better prognosis than previously assumed. These findings raise doubts about the value of extra-intracranial surgical bypass procedures in patients with these lesions. 相似文献
952.
Hasegawa BH; Naimuddin S; Dobbins JT d; Mistretta CA; Peppler WW; Hangiandreou NJ; Cusma JT; McDermott JC; Kudva BV; Melbye KM 《Radiology》1986,159(2):537-543
The feasibility of producing patient-specific beam attenuators for chest radiography has been investigated using an anthropomorphic phantom and a human volunteer. A low-dose test exposure is digitized, processed, and used to print a small cerium filter, which is placed in the x-ray beam near the collimator. The final radiograph is recorded on film. The technique results in relatively uniform film exposure, so that structures in all regions of the chest are simultaneously displayed with optimal film contrast. The equalized exposure improves image quality in the normally underpenetrated regions and reduces the role of cross-scatter from the lungs. The image is analogous to optical or computer-processed unsharp masking techniques, but the processing is accomplished in the x-ray beam and results in an improved exposure distribution, giving advantages that cannot be achieved with image processing techniques alone. 相似文献
953.
JC Szepietowski† J Salomon† P Pacan‡ E Hrehorów† A Zalewska§ 《Journal of the European Academy of Dermatology and Venereology》2008,22(7):795-799
The aim of this study was to determine the frequency of body dysmorphic disorder (BDD) identified by Polish dermatologists and to evaluate the treatment modalities applied by them.
Methods A specially designed questionnaire was distributed to 172 dermatologists. A total of 118 doctors responded (68.6%). The dermatologists were asked regarding demographic data, frequency of BDD in their everyday practice and methods of treatment they used in managing BDD patients.
Results During the whole working period, over the half of dermatologists (64%) had observed at least one BDD patient in their practice. One fifth (20%) of the respondents observed 1 or 2 BDD cases during the past 5 years, 14% observed 3 to 5 such patients, 7% observed 5 to 10 BDD cases, and 5% of the doctors reported seeing more than 10 BDD patients within this period. Almost 18% of dermatologists were currently treating a BDD patient. Our data show that 40.7% of the respondents always ask and 28.8% often ask for a psychiatric opinion. More experienced dermatologists statistically more frequently ( P < 0.05) obtained a psychiatric opinion about their patients. Only a small group of dermatologists (15.3%) use their own pharmacological treatment. If they do so, they first use anxiety-relieving drugs and placebo.
Conclusion BDD is a quite common disorder; however, not all dermatologists are sufficiently prepared to treat it. There is an urgent need for training of dermatologists on the effective approach to psychodermatoses. 相似文献
Methods A specially designed questionnaire was distributed to 172 dermatologists. A total of 118 doctors responded (68.6%). The dermatologists were asked regarding demographic data, frequency of BDD in their everyday practice and methods of treatment they used in managing BDD patients.
Results During the whole working period, over the half of dermatologists (64%) had observed at least one BDD patient in their practice. One fifth (20%) of the respondents observed 1 or 2 BDD cases during the past 5 years, 14% observed 3 to 5 such patients, 7% observed 5 to 10 BDD cases, and 5% of the doctors reported seeing more than 10 BDD patients within this period. Almost 18% of dermatologists were currently treating a BDD patient. Our data show that 40.7% of the respondents always ask and 28.8% often ask for a psychiatric opinion. More experienced dermatologists statistically more frequently ( P < 0.05) obtained a psychiatric opinion about their patients. Only a small group of dermatologists (15.3%) use their own pharmacological treatment. If they do so, they first use anxiety-relieving drugs and placebo.
Conclusion BDD is a quite common disorder; however, not all dermatologists are sufficiently prepared to treat it. There is an urgent need for training of dermatologists on the effective approach to psychodermatoses. 相似文献
954.
955.
Electrosurgery is a useful tool in the orthopedic procedures outlined, including lateral release, synovial lesions, and shoulder impingement syndrome. The salient positive characteristic of electrosurgery is the capacity to obtain immediate and thorough hemostasis, thereby allowing the patient to begin a rehabilitative program far sooner than with conventional operative techniques. Less hemarthrosis also lowers the level of postoperative pain and the risk of postoperative infection. By becoming familiar with some of the basics of electrosurgery, including equipment and electrosurgical principles, the surgeon and staff can better utilize electrosurgery and be aware of the potential, yet avoidable, complications. The future appears bright for electrosurgery, with new equipment and procedures being developed, but more research is needed to clarify the long-term effects on tissues involved and the clinical results of patients. 相似文献
956.
J K Stehr-Green L McCaig H M Remsen C S Rains M Fox D D Juranek 《The American journal of tropical medicine and hygiene》1987,36(2):338-342
In June 1985, we investigated an outbreak of cryptosporidiosis at a day-care center in Florida. Through day-care center-wide stool screening, 33% (28/84) of the children and 22% (4/18) of the staff members submitting stool specimens were found to have cryptosporidiosis. Children 12-35 months of age and their teachers were at highest risk. All but 1 of the Cryptosporidium-positive patients reported diarrhea, which lasted between 1-44 days. Serial stool specimens were obtained from 8 infected individuals (5 children and 3 adults). Duration of oocyst shedding ranged from 8 to more than 50 days and continued in 5 individuals after diarrhea ceased. No relationship was found between duration of oocyst shedding and the age of the patient or duration or severity of diarrhea. Results of the investigation indicate that infected individuals may continue to excrete oocysts and, therefore, may remain infectious for days or weeks after gastrointestinal symptoms disappear. 相似文献
957.
直到最近为止,冠心病的内科治疗原则仍是降低心肌需氧量。由于粥样硬化病变一直认为是固定不变的狭窄,不可能增加冠脉血流量,因此认为用药物扩张冠状动脉是徒劳的。在近几年内这些概念有了基本转变。然而仅能引起远端心肌内小动脉扩张的药物却起着相反的作用。当心外膜冠状动脉有粥样硬化时,冠状小动脉扩张可加重血流分布异常,导致心肌缺血。冠状循环由近端大冠状动脉及其分枝小动脉组成的心肌内动脉网构成。近端大冠状 相似文献
958.
L M Anderson J M Ward S D Fox H J Isaaq C W Riggs 《International journal of cancer. Journal international du cancer》1986,38(1):109-116
Polychlorinated biphenyls (PCBs) are widespread, chemically-stable environmental contaminants; some congeners are commonly found in human adipose tissue and breast milk. We investigated the effects of a single dose of one PCB mixture (Aroclor 1254) on tumors initiated by N-nitrosodimethylamine (NDMA), also a common environmental agent. Infant outbred Swiss male mice were treated with NDMA (5 mg/kg) i.p. on the 4th day of life, to initiate lung and liver tumors. Four days later each received a single intragastric dose of PCBs (50, 250, or 500 mg/kg of Aroclor 1254) or oil. Groups were killed 16 and 28 weeks later. At both endpoints the mice given 500 mg/kg PCBs after NDMA developed twice as many lung tumors (alveologenic adenomas) as those treated with NDMA only, a significant difference. The PCBs alone did not cause lung tumors. This is the first demonstration of tumor promotion by PCBs in an extrahepatic organ, and it occurred after a single exposure. There were also complex, multiple effects on NDMA-caused liver tumors (adenomas and carcinomas) and on focal hepatocellular proliferative lesions: PCB treatment after the NDMA was associated with decreased number but increased size of these tumors and foci. All of these changes were accompanied by retention in the bodies of 0.1-6 ppm PCBs, as indicated by gas chromatography with electron capture detection. Of this, 80% or more consisted of 2,4,5,2',4',5'-and 2,3,4,2',4',5'-hexachlorobiphenyls in about equal amounts for periods up to 28 weeks. These results point to a need for both experimental and epidemiological studies of the effect of PCB body burden on tumor development. 相似文献
959.
Mercado S; Hunter DW; Castaneda-Zuniga WR; Amplatz K; Young AT; Cardella JF; Lange PH; Hulbert JC; Reddy P 《Radiology》1986,158(1):207-209
Percutaneous nephrostolithotomy, which can require a double puncture, is presently the method of choice in our institution for the removal of renal stones. Patients that underwent this procedure were evaluated to identify the possible reasons for the double puncture. Of 200 patients evaluated, 14 needed a second tract. The three variables that determined whether a second puncture was needed, in order of importance, were number and size of the stones, with second tracts needed in patients with multiple stones and staghorn calculi; anatomical variations of the renal collecting system itself, with bifid systems the most significant anatomic variation; and the dexterity of the radiologist in performing the puncture and the ability of the urologist to extract the stone. Second tracts were needed more frequently in patients who presented with stones in both the lower and middle poles of the collecting systems. 相似文献
960.
A Wolff J C Atkinson A A Macynski P C Fox 《NCI monographs : a publication of the National Cancer Institute》1990,(9):87-90
Salivary gland dysfunction is a common side effect of cancer therapies. Salivary secretions are reduced rapidly after starting head and neck radiotherapy. Salivary gland dysfunction has also been linked to bone marrow transplantation and to cytotoxic chemotherapy. Salivary gland stimulation during radiation has been suggested as a means of reducing radiation damage. Results of an ongoing study investigating the effects of pilocarpine on radiation-induced salivary gland dysfunction suggest that parotid function was preserved, but not submandibular/sublingual function. Also, patients receiving pilocarpine had less frequent oral complaints. Further research is necessary to develop means of preventing or alleviating the salivary side effects of cancer therapies. 相似文献