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New inferior vena caval filters for percutaneous placement were made by attaching filter wires similar to those in the bird's nest inferior vena caval filter onto expandable metallic stents. These stents formed a base on which to anchor the filter to the wall of the inferior vena cava. The stent filter can be introduced through a 12- to 13-French catheter sheath system. The system was successfully tested in 13 dogs.  相似文献   
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A cohort of children in North-East Thailand was followed from birth to 2 years of age in an attempt to throw light on factors determining the development of stunting in linear growth. By 2 years the group as a whole had an average deficit in height of nearly -2 standard deviations. Those index children whose sibs were stunted had larger deficits than those with normal sibs. Their mothers were also shorter and lighter. These findings suggest that it is possible to think in terms of stunted families. No differences were identified in socio-economic factors and the prevalence of infection was in general low. Dietary intakes estimated by 24-hour recall, supplemented at 1 and 2 years by 24 h weighing, were satisfactory for most nutrients except iron, calcium and niacin. Intakes of Ca and P were lower in the more stunted children. A number of variables were measured in urine and blood at 1 and 2 years but few relationships could be established with the degree of stunting. Excretions of calcium and phosphorus showed weak negative correlations with height. On average the serum concentration of calcium was satisfactory but that of phosphorus was somewhat low. Concentrations of somatomedin C, thyroxin and vitamin D were within reported normal ranges, with no relation to the degree of stunting. From a comparison of the linear growth of these children with the results of other reports from Thailand it is suggested that environmental factors have produced stunting in the cohort as a whole, but the cohort is essentially homogeneous, showing within it a normal range of genetic variation. If that is so, major differences in intake or biochemistry between the taller and shorter children would not be expected. The problem remains of why the group as a whole is stunted. This is the first systematic attempt to assess biochemical factors that may be related to stunting in Third World children; these results are essentially negative, although there are hints that point at a possible deficiency of calcium.  相似文献   
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Twenty patients with colon cancer metastatic to the liver underwent successful hepatic resection and adjuvant perioperative therapy that included hepatic arterial mitomycin C and floxuridine (FUDR). The median survival for all 20 patients was 51 months: 10 are still alive with a median postoperative follow-up of 49 months; 6 are disease-free with a median postoperative follow-up of 43 months. Among 10 patients in whom the surgical margins of the specimen contained tumor cells, the median survival was 52 months. This survival was comparable to that among 10 patients in whom the surgical margins were tumor free (P = 0.22). Neither the number of metastatic liver deposits nor the disease-free interval between the primary diagnosis of colorectal carcinoma and the development of liver metastases significantly affected survival. A transient chemical hepatitis which resolved before the next scheduled treatment was associated with 50% of arterial chemotherapy cycles (approximately 70% of the patients). Gastric or duodenal ulcerations occurred in 23% of the patients. Surgical complications were either pulmonary such as pleural effusion or atelectasis, or wound infections and subphrenic abscesses. Although these results compare favorably with the results in previously published series, this aggressive adjuvant chemotherapy appears to be particularly justified in patients with tumor positive surgical margins or those with multiple tumor masses and, therefore, are characterized by a poor prognosis.  相似文献   
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Background: The K-ras oncogene is activated by point mutations at codon 12 in most patients with exocrine pancreatic cancer. Mutant-enriched polymerase chain reaction (PCR) amplification can enhance the detection of mutated K-ras. This technique was applied to patients undergoing percutaneous fine-needle aspiration (FNA) biopsy of suspect pancreatic lesions. Methods: Twenty-five patients underwent percutaneous FNA of the pancreas for cytologic and molecular analysis. After preparing cytologic smears, the 22-gauge needle and syringe used for FNA were rinsed in RPMI-1640. The specimen was centrifuged, and DNA was extracted from the supernatant and subjected to mutant-enriched PCR using appropriate mismatched primers that introduce a BstNI restriction endonuclease cleavage site at codon 12 of wild-type, but not mutant, K-ras. After digestion with BstNI, the DNA was reamplified. To increase assay sensitivity, the final five PCR cycles were completed incorporating 5 μCi of (α-32P)dCTP. The DNA was then redigested and subjected to gel electrophoresis and autoradiography. Results: The median amount of DNA retrieved per specimen was 3.33 μg. Mutant K-ras was detected as a band of 143 bps; residual wild-type DNA was seen as a 114-bp fragment. Twenty-one of 25 specimens demonstrated mutated K-ras DNA. Two patients with nondiagnostic cytology results had mutated K-ras DNA; adenocarcinoma of pancreatic origin was confirmed in both cases after pancreatectomy. Conclusion: The molecular diagnosis of pancreatic cancer through identification of mutations in K-ras can be readily performed on specimens obtained by percutaneous FNA. As aggressive multimodality management of this disease becomes more common, pretreatment analysis of molecular determinants may have greater clinical significance. Presented at the 48th Cancer Symposium of The Society of Surgical Oncology, Boston, Massachusetts, March 23–26, 1995.  相似文献   
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Parenchymal changes of the liver in cholangiocarcinoma: CT evaluation.   总被引:5,自引:0,他引:5  
We evaluated parenchymal changes of the liver in 92 patients (41 peripheral types and 51 hilar types) with cholangiocarcinomas studied by bolus-enhanced computed tomography (CT). In 39% of patients with the peripheral type, a wedge-shaped increased enhancement of the liver was observed peripheral to the tumor on bolus-enhanced CT. Tumor was observed in all cases. In 58.8% of patients with the hilar type, a segmental or lobar increased degree of enhancement of the liver was observed, but the tumor was demonstrated in only 58.8%. Atrophy was accompanied by areas of increased enhancement in 80% of hilar type and 25% of peripheral type. Areas of increased degree of enhancement corresponded to a wedged-shaped perfusion defect on CT during arterial portography. On magnetic resonance imaging (MRI), those lesions showed hyperintensity on T2-weighted images. Most of these changes were considered to be due to reversible hepatic parenchymal ischemia secondary to portal vein invasion by the tumor.  相似文献   
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We assessed the therapeutic efficacy and toxicity of continuous hepatic infusion of vinblastine in the treatment of breast cancer predominantly metastatic to the liver. Twenty-six patients previously treated with one or more chemotherapeutic regimens received vinblastine at a dose of 2.0 mg/m2 daily for 5 days, via percutaneously inserted intra-arterial catheters, at 3-4-week intervals. Nine of 25 evaluable patients (36%) achieved partial response and four (16%) had minor response. For responding patients, the median time to disease progression was 21 weeks (range, 12-99), with a median survival of 11 months (range, 4-29) from the beginning of hepatic arterial infusion. The toxicity of the treatment was acceptable, and drug-related effects were comparable to those seen in patients with breast cancer treated by iv continuous infusion of vinblastine at slightly lower doses. We observed two episodes of transient inappropriate antidiuretic hormone secretion. Percutaneous hepatic arterial infusion of vinblastine had significant activity in the treatment of breast cancer metastatic to the liver.  相似文献   
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Pediatric Surgery International - Human breast milk (HBM), which contains an abundant supply of exosomes, is known to prevent necrotizing enterocolitis (NEC). Preterm infants are commonly given...  相似文献   
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