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991.
A clinicopathologic analysis of 1503 thyroid tumors was conducted revealing 82.9% of benign and 17.8% of malignant lesions. The most common type of benign tumor was simple adenoma (62.1%) and of malignant tumor, papillary adenocarcinoma (52.5%). The malignant to benign tumor ratio was 1:4.8. The male to female sex ratio was 1:2.6 in the malignant and 1:3.8 in the benign tumors. The overall 5- and 10-year survival rates for all cancers were 67.7% and 47.6%, respectively. It is suggested that the follicular carcinoma could further be divided into well differentiated (papillary and follicular), poorly differentiated (including squamous cell carcinoma) and undifferentiated types.  相似文献   
992.
The development of a deep infection following vascular reconstructive surgery is the most demanding situation encountered in vascular surgery and requires diagnostic investigations that will vary with the hospital concerned and a targeted, early and aggressive attack on the infection both systemically and locally; in addition, local reconstruction carried out with autologous materials in association with sutures that are absorbed over the medium term – also referred to as autologous reconstruction – is helpful in many cases. A range of autologous reconstruction procedures is available for application at all sites of infection, allowing adequate and effective treatment. In most cases these can ensure a secure blood flow situation, win time, and keep the patient alive and conserve his or her extremity. The main priority is to combat the infection and make it possible to keep the patient alive and the extremity affected intact. When the stage of deep infection has been reached even recovery of the initial status once the infection is cured can be regarded as a success. After an appropriate time it is always possible to reoperate on the basis of the principles of vascular surgery.  相似文献   
993.
The purpose of this comparative study was to evaluate the response of primary splenic low‐grade non‐Hodgkin's lymphomas (NHL) to chemotherapy, splenectomy, and chemotherapy combined with splenectomy in order to elaborate the optimum treatment modality. A total of 104 patients (age range: 15–82 years) with primary low‐grade B‐cell NHL of the spleen were comprised by our study. Stage IV disease was determined in 102 (98.1%) cases. Regarding the treatment modality, splenectomy was performed in 14 patients, early splenectomy and single‐agent chemotherapy in 15, early splenectomy and combined chemotherapy in 19, single‐agent chemotherapy in 23, and combined chemotherapy in 33. In the above‐mentioned order, complete remission rate was following: none, 40.0, 31.6, 21.8, and 18.2%. Partial remissions were achieved in 85.7, 46.7, 57.9, 30.4, and 69.7% of cases, respectively. The median remission duration turned out to be longer (74.5 months) in the group of patients with complete remissions attained by means of splenectomy and combined chemotherapy. Local relapses in the spleen developed in 19 (72.7%) patients treated with combined chemotherapy and in 9 (90.0%), who had undergone single‐agent chemotherapy. The 5‐year overall survival was 54.4% after splenectomy, 39.4% after single‐agent chemotherapy, and 37.1% after combined chemotherapy, being significantly higher (P < 0.05) after splenectomy and single‐agent chemotherapy (67.2%), and splenectomy followed by combined chemotherapy (64.7%). Early splenectomy combined with chemotherapy is the optimum treatment option for primary low‐grade NHL of the spleen because of the superiority in complete remission rate, remission duration, and in overall survival rate. Splenectomy leads to somatic compensation of patients, makes impossible local relapsing in the spleen, prevents continuous dissemination from the primary tumor site, and mostly corrects cytopenias, creating better conditions for chemotherapy.  相似文献   
994.
狂犬病的特点及防制策略   总被引:9,自引:1,他引:8       下载免费PDF全文
  相似文献   
995.
We report a fluid level in an acute extradural haematoma developing after placement of a ventriculoperitoneal shunt for hydrocephalus. This fluid level was thought to be due to a mixture of blood and cerebrospinal fluid.  相似文献   
996.
N-(4-Cyanophenyl)-N'-(2-carboxyethyl)urea (2), an analogue of suosan [1,N-(4-nitrophenyl)-N'-(2-carboxyethyl)urea], is a known high-potency sweetener derived from beta-alanine. Sulfonic and phosphonic acid analogues of 2 were prepared to develop structure-activity relationships through modification of the carboxylic acid region of this family of sweeteners. Neither of the carboxylic acid replacements resulted in sweet analogues. However, we found that N-(4-cyanophenyl)-N'-[(sodiosulfo)methyl]urea (7) is an antagonist of the sweet taste response. The bitter taste response to caffeine, quinine, and naringin was also antagonized. Antagonist 7 was found to inhibit the sweet taste perception of a variety of sweeteners. Antagonist 7 had no effect on the sour or salty taste response.  相似文献   
997.
Summary Aminophylline reversed the protective action of both, D-3-(2-carboxypiperazine-4-yl)-1-propenyl-1-phosphonic acid (D-CPP-ene — a competitive NMDA antagonist) and valproate (used as a conventional antiepileptic drug for comparative purposes) against maximal electroshock-induced seizures. The respective ED50 values of aminophylline were 55.7 and 98.4mg/kg i.p. However, aminophylline (up to 100mg/kg i.p.) did not influence the protective efficacy of 1-(4-aminophenyl)-4-methyl-7,8-methyl-enedioxy-5H-2, 3-benzodiazepine (GYKI 52466 — a non-NMDA antagonist). Strychnine affected the protection provided by D-CPP-ene, GYKI 52466, and valproate against maximal electroshock — the ED50 values of strychnine for the reversal of the anticonvulsive effects of D-CPP-ene, GYKI 52466 or valproate were 0.082, 0.35 and 0.28mg/kg s.c., respectively.An involvement of strychnine sensitive glycinergic receptor-mediated events in the mechanism of the anticonvulsive activity of excitatory amino acid antagonists and valproate may be postulated. The ineffectiveness of aminophylline to reduce the anticonvulsive effects of GYKI 52466 may distinguish a new class of antiepileptic drugs offering an advantage over conventional antiepileptics in patients with epilepsy, requiring aminophylline for pulmonary reasons.  相似文献   
998.
999.
The effect of radix Paeoniae rubrae extract on mesenteric microcirculation was studied in 20 scalded SD rats. It was found that this drug effectively prevented some disturbances of mesenteric microcirculation induced by burn. It inhibited the contraction of arterioles, decreased the adhesion of leucocytes on the venous wall, reduced and delayed the aggregation of erythrocytes in microvessels.  相似文献   
1000.
Nitrous acid, a component of photochemical smog and a common indoor air pollutant, may reach levels of 100 ppb where gas stoves and unvented portable kerosene heaters are used. Nitrous acid is a primary product of combustion and may also be a secondary product by reaction of nitrogen dioxide with water. Because the usual assays for nitrogen dioxide measure several oxides of nitrogen (including nitrous acid) together, previous studies of indoor nitrogen dioxide may have included exposure to and health effects of nitrous acid. To assess the respiratory effects of nitrous acid exposure alone, we carried out a double-blinded crossover chamber exposure study with 11 mildly asthmatic adult subjects. Each underwent 3-hr exposures to 650 ppb nitrous acid and to filtered room air with three 20-min periods of moderate cycle exercise. Symptoms, respiratory parameters during exercise, and spirometry after exercise were measured. A statistically significant decrease in forced vital capacity was seen on days when subjects were exposed to nitrous acid. This effect was most marked at 25 min and 85 min after exposure began. Aggregate respiratory and mucous membrane symptoms were also significantly higher with nitrous acid. We conclude that this concentration and duration of exposure to nitrous acid alters lung mechanics slightly, does not induce significant airflow obstruction, and produces mild irritant symptoms in asthmatics.  相似文献   
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