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991.
BACKGROUND: Preoperative factors including age and body habitus affect intraoperative hypothermia during general anesthesia. We hypothesized that preoperative blood pressure also plays a contributory role in the induction of intraoperative hypothermia. METHODS: We evaluated the effect of preoperative systolic blood pressure (SBP) on core temperature during lower abdominal surgery under general anesthesia. In 36 female patients under 65 years of age, patients with a preoperative SBP of 140 mmHg or greater upon arrival in the operating theater were assigned to the high SBP group (n=18), while those with SBP below 140 mmHg were assigned to the normal SBP group (n=18). Anesthesia was maintained with isoflurane and nitrous oxide combined with epidural buprenorphine, and routine thermal care was provided intraoperatively. RESULTS: There were no significant differences in age, height or weight between the two groups. Tympanic membrane temperature in the normal SBP group started to decrease significantly from 15 min after induction of anesthesia compared to that in the high SBP group, and continued to decrease further at two hours after induction. Vasoconstriction threshold, determined to be tympanic membrane temperature at the time when a forearm minus finger skin surface gradient exceeded 0 degrees C, was significantly higher in the high SBP group than in the normal SBP group. CONCLUSION: These results suggest that preoperative SBP has some preventive effect on the decrease in intraoperative core temperature during lower abdominal surgery under general anesthesia.  相似文献   
992.
993.
Aortic dissection rarely occurs in 2 or more family members without Marfan's syndrome. This report describes two aged siblings who underwent emergency operations for aortic dissection. Case 1: A 71-year-old female (sister), who had Stanford type B aortic dissection, underwent replacement of the descending aorta with a Hemashield graft. Case 2: A 72-year-old male (brother of case 1), who had Stanford type A aortic dissection, underwent replacement of the ascending aorta with a UBE graft following the closure of the entry located in the proximal arch. Neither of 2 siblings nor other family members had any features of the Marfan's syndrome. It is proposed that two aortic dissections occurred coincidentally in one family without Marfan's syndrome.  相似文献   
994.
We report a case of traumatic diaphragmatic hernia (TDH) resulting from continuous thoracic drainage and was successfully treated by surgical procedures. A 45-year-old man was admitted to our department due to shock after a blunt trauma by a traffic accident. As he revealed left hemothorax on admission, continuous thoracic drainage was performed. Soon after the drainage, diaphragmatic hernia occurred as an incarceration of the spleen into the thoracic cavity. In the literature, 80 cases with TDH have been reported in Japan since 1986. The purpose of this study is to discuss the mechanism of TDH in the acute phase and to consider its appropriate diagnostic tools. The following two results were obtained. (1) TDH may be appeared during the clinical course, especially after a continuous thoracic drainage, in patients with damaged diaphragm by blunt traumas. (2) CT is the most effective tool for the diagnosis of TDH.  相似文献   
995.
Subclavian artery aneurysms are relatively rare, and the surgical approach depends on the location (intrathoracic or extrathoracic) and size of the aneurysm. Right subclavian artery aneurysms are usually operated upon using a supraclavicular approach or median sternotomy incision with right supraclavicular extension. We treated a right intrathoracic subclavian artery aneurysm by subclavicular trans-sternal approach. This surgical approach is recommended for treatment of right intrathoracic subclavian artery aneurysms for its easy access and excellent cosmetic results.  相似文献   
996.
The influence of suturing on cell infiltration into the meniscus and surrounding tissue is not well known. Histologic changes in the meniscus after suturing and prediction of histologic changes using magnetic resonance imaging were studied. Forty knees in 20 mongrel dogs were studied using four types of 4-0 suture material: nonabsorbable monofilament, nonabsorbable braided, absorbable monofilament, and absorbable braided. Each type of suture material was used for meniscal suture on eight knees each. The other eight knees were not subjected to meniscal suture. Specimens obtained at 1 and 3 months were studied by magnetic resonance imaging and light microscopic analysis. The maximum width of change of meniscal tissue was measured. Changes from the nonabsorbable suture group were smaller than that of the absorbable suture group in magnetic resonance imaging. Histologic changes as seen by light microscope were larger in the absorbable group than in the nonabsorbable group at 1 and 3 months after surgery. Injury was found in the articular cartilage of the femoral condyle in the nonabsorbable braided suture group. Histologic changes were significantly greater when changes in magnetic resonance imaging signal intensity were larger. The current study showed that non-absorbable monofilament suture material results in the least damage to the meniscus and surrounding tissue.  相似文献   
997.
PURPOSE: Hypertension is an important complication of multicystic dysplastic kidney and it has been suggested that it is induced by renin. Little information is available on renin production in this disease. To assess renin production we examined the distribution of renin containing cells in multicystic dysplastic kidneys using immunohistochemical methods. MATERIALS AND METHODS: Immunohistochemical examination of renin was performed in 29 multicystic dysplastic kidneys from 14 boys and 15 girls 1 month to 10 years old using rabbit anti-human renin antibodies. In all cases normal renal function was confirmed by the serum creatinine level and no proteinuria on urinalysis. Two patients had the complication of hypertension before removal of the multicystic dysplastic kidney but plasma renin activity was normal. RESULTS: Immunostaining of renin was observed in 26 of 29 multicystic dysplastic kidneys (90%). Histologically multicystic dysplastic kidney involved scarred and dysplastic areas. Renin positive cells were observed predominantly in the scarred areas, mainly in the juxtaglomerular apparatus of mature glomeruli, interlobular arteries and some mature tubules. Immunopositive renin was sparsely noted in the juxtaglomerular apparatus or Bowman's capsules of occasional immature glomeruli in dysplastic areas. CONCLUSIONS: Our observations suggest that multicystic dysplastic kidney may have the ability to produce renin. Renin producing cells in the juxtaglomerular apparatus of mature glomeruli and interlobular arteries in the scarred areas may be the predominant source of renin production in this organ.  相似文献   
998.
Spontaneous perforation of the bile duct (SPBD) is a rare disease in children. Pancreatico-biliary maljunction (PBM) has been postulated to contribute to its etiology. We have treated three children with SPBD over 30 years, two of whom had PBM. There was one boy and two girls aged 10 months to 2 years with symptoms of abdominal distension, vomiting, abdominal pain, jaundice, and acholic stools. The diagnosis of SPBD was made by paracentesis showing biliary ascites, and primary biliary and intra-abdominal drainage was performed in all cases. The site of perforation was at the connection of the common bile duct (CBD) with the cystic duct in all cases. In two cases reflux of contrast into the pancreatic duct was noted, the common channel was long (17 and 12 mm, respectively), and the bile amylase level in the CBD was abnormally high (50,000 and 67,000 IU/l, respectively). In the third patient there was no reflux of contrast into the pancreatic duct and the bile amylase and trypsin levels in the CBD and gallbladder were not measurable. Thus, SPBD in children may not be due solely to PBM, but may involve multiple mechanisms. Accepted: 11 January 2000  相似文献   
999.
We report a case of adenocarcinoma of the rectum with foci of metaplastic shadow cells. The patient was a 65 year old man with anemia. Macroscopically the tumor was an ordinary rectal cancer. Microscopically, in addition to the features of moderately differentiated adenocarcinoma invading the subserosa, islands of shadow cells in tumor nests were detected in both primary and one of three pericolic metastatic lymph node lesions. Neoplastic glandular cells showed gradual transition to shadow cells. An antibody specific for high-molecular-weight cytokeratins reacted with the shadow cells and intermediate zone epithelial cells surrounding them, but no CEA, low-molecular-weight cytokeratins or cyclin D1 was detectable in them. Cytokeratin 14 was expressed only in the transitional zone epithelial cells. The intermediate zone epithelial cells were regarded as metaplastic squamous cells, from which the shadow cells were derived. The patient died of multiple liver metastases nine and a half months after surgery. To our knowledge, this is the first report of an immunohistochemical study of rectal adenocarcinoma containing shadow cells not only in the primary lesion but also in a metastatic lymph node.   相似文献   
1000.
The MAD (mothers against decapentaplegic)-related genes, Smad2 (former name MA DR2 or JV18-1 ) and Smad4 (former name DPC4 ), have been identified on chromosome 18q21.1, We analyzed 30 primary esophageal squamous cell carcinomas (ESCC) and 7 cell lines derived from ESCC for intragenic mutations and loss of heterozygosity (LOH) of the Smad2 and Smad4 genes. LOH was detected in 5 of 14 (35%) informative cases. However, no mutations in either gene were detected in either the primary carcinomas or the cell lines, and only a G-to-A base transition within the 3'-untranslated region of the Smad4 gene was observed in a carcinoma. There were no homozygous deletions in either of the genes in the cell lines. MAD -related genes on chromosome 18q21.1 are altered infrequently in ESCC.  相似文献   
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