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1.
The efficacy of intravenous thrombolytic agents in preserving left ventricular function and in decreasing mortality from an acute myocardial infarction was demonstrated in the 1980s. The 1990s will concentrate on adjunctive therapy to thrombolysis in the treatment of an acute myocardial infarction.  相似文献   
2.
The surgical treatment of rectal cancer of the middle third remains controversial. We treated 30 consecutive patients with preoperative radiotherapy (45 Gy) and low anterior resection. Anastomoses were performed with a stapler. Intraoperative frozen-section examination of the rectal margin established that it was free of tumor. Two patients died of surgery-related causes. Median follow-up of the remaining patients is now 52 months (range: 26 to 76 months). Eight patients had recurrences documented at surgical re-exploration: two local (pelvic) only, three local and distant, and two distant only. Local recurrences happened despite a frozen-section examination of the rectal margin negative for tumor. Six of the eight patients who experienced a recurrence have died of disease progression. Distant metastases were found in six other patients during follow-up; they subsequently died. Thus, our therapeutic approach was not associated with decreases in local or overall recurrences.  相似文献   
3.
J Morales  P Kibsey  P D Thomas  M J Poznansky  S M Hamilton 《The Journal of trauma》1992,33(2):221-6; discussion 226-7
The bacterial translocation hypothesis was tested in two studies (acute and subacute) in a porcine model of hemorrhagic shock. Male pigs (30-40 kg each) under general anesthesia had their femoral vein, femoral artery, and portal vein catheterized. After stabilization (1 hour) they were bled (40% of blood volume) over 30 minutes, then maintained in the hypotensive state (MAP = 30-40 mm Hg) for 2 hours, following which, according to randomization, they entered the control group or were resuscitated with whole blood (WB group) or with lactated Ringer's solution (LR group). In the acute study, the mesenteric efferent lymphatic was also cannulated, the control group was not resuscitated, and the animals remained under general anesthesia to the end of the experiment (8.5 hours), when gut tissue was obtained for histologic study and measurement of lipid peroxidation. In the subacute study, the control group was not bled, the animals were awakened at 6.5 hours, and the portal vein catheter remained in situ until 48 hours. In both studies, samples of portal blood were obtained for culture at regular intervals and on completion, samples from mesenteric lymph nodes (MLNs) for culture were taken in the acute study, and in the subacute study samples from MLNs, spleen, and liver were obtained. In the acute study significant bacterial translocation to the MLNs and portal blood did not occur among the controls (n = 3), the LR group (n = 5), and the WB group (n = 6). Significant evidence of lipid peroxidation was found in both the LR and WB groups. Histologic assessment showed no difference among the groups.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
4.
Dietary factors are widely considered to be largely responsible for the different cancer incidences observed in different populations. In the present study we investigated the possible influence of dietary habits on the incidence of digestive cancer in the provinces of Spain. Data on specific mortality due to digestive cancer corresponding to the period 1975 to 1985 were obtained from the Instituto Nacional de Estadística. Nutritional data on the different provinces were in turn gathered from the Instituto de Nutrición del Consejo Superior de Investigaciones Científicas. The information was processed by the SPSS statistical software package. Lifestyle and socio-cultural factors are found to influence dietary risk factors in digestive cancer, particularly among women. The most significant correlations with the different cancers studied corresponded to total energy intake (responsible for 27.4% of variance), animal fats, and smoked fish and coffee. The latter is related to oral and esophageal cancer in particular (responsible for 15.4% of variance). Consumption of carrots and frozen vegetables is responsible for 6.5% of variance, vs. 4.4% of variance for alcoholic beverages, sugar, and Vitamin D. Differences are noted between both the sexes and their relationship to the different cancers studied.  相似文献   
5.
The objective of this study was to determine whether the aging process influences the changes in the electrophysiological properties of motoneurons that occur as a consequence of axotomy. Accordingly, using intracellular recording and stimulating techniques, the basic electrical properties of control (unaxotomized) and axotomized spinal cord motoneurons of aged cats were determined. Compared with control motoneurons, axotomized motoneurons exhibited increases in input resistance (Rin), membrane time constant (τb) and the equalizing time constant (τc). While the electrotonic length (L) remained unchanged, axotomy induced a decrease in the total cell capacitance (Ccell. The post-axotomy reduction of Ccell indicates that the motoneuron surface area was reduced and the increased membrane time constant indicates that there was an increase in membrane resistivity (Rm). The post-axotomy conservation of L accompanied by an increase in Rm suggests that aged axotomized motoneurons undergo geometrical changes. Furthermore, calculations based on cable theory suggest that the diameter of the equivalent cylinder (d) decreased following axotomy, whereas the equivalent cylinder length (l) remained unaffected. It is concluded that axotomy produces significant alterations in the soma-dendritic portion of aged spinal motoneurons, as indicated by the changes found in their passive electrophysiological properties, and that the pattern of the response that occurs in axotomized motoneurons of adult cats is also present in axotomized motoneurons of aged animals.  相似文献   
6.
Superficial bladder cancer is one of the few solid human malignancies in which immunotherapy has been proved to be effective. Bacillus Calmette-Guérin was the vaccine which opened the door for this innovative approach. In an era of remarkable achievements in biotechnology, it is truly amazing that this throwback to the Stone Age of tumor immunology has not yet been replaced by a more (or equally) effective substitute. Potential candidates are already on the horizon and deserve a comprehensive evaluation. They must show not only that they are devoid of significant adverse effects but that they possess, beyond a doubt, superior antineoplastic activity. Even more remarkable is that one of the oldest vaccines still in use could emerge in a new role as an effective antineoplastic agent. Bacillus Calmette-Guérin has demonstrated an uncanny capacity for effectiveness as therapy for human diseases. Its protective effect against tuberculosis is well recognized, and its contribution to cancer therapy is widely known. A new and increasing repertoire has recently been presented: two separate groups of researchers have employed the vaccine successfully as a vehicle to express antigen-encoded genes from other pathogens. The exciting aspect of these recent studies resides in the demonstration that the altered vaccine is able to induce humoral and cell-mediated immune responses to the recombinant antigens, including the human immunodeficiency virus (HIV). Thus, BCG once more attracts enormous interest from the scientific community for its versatility and potential as a therapeutic agent.  相似文献   
7.
The correct identification of syndromes and other congenital malformations at an early age is critical for the child, family and care providers. Most specialists who conduct large screenings of young children are not adequately trained to recognize signs and symptoms that should lead to appropriate referral to the clinical geneticist and/or diagnostic team. A systematic approach for recognizing important signs is presented here; a Craniofacial Screening Profile. Following a brief training program, the Profile was validated by 39 speech-language pathologists in screening 3,539 kindergarten and first grade children. The results were excellent (specificity was 99.6%), demonstrating that with limited training, specialists can effectively screen for important signs and symptoms of a major group of syndromes and other congenital malformations.  相似文献   
8.
Intraperitoneal chemotherapy was administered to 13 patients with peritoneal carcinomatosis, using acute peritoneal dialysis catheters immediately before the administration of the chemotherapy. A total of 59 cycles were administered, with insertion of the corresponding catheter. There were no inflow or outflow problems and no insertion-related complications. With the removal of the catheter after its use, there is no risk of abdominal infections.  相似文献   
9.
10.
Calcium channel blockers can act on dopaminergic systems, and some reports suggest that they could be useful for the treatment of several movement disorders. In order to assess the efficacy of nicardipine in tics disorders we performed a prospective open non-controlled study which included 10 previously untreated patients. Our results suggest that nicardipine could be a useful and safe treatment for tics.  相似文献   
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