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91.
PURPOSE: The aim of this study was to clarify genetic and epigenetic alterations occurring during renal carcinogenesis. EXPERIMENTAL DESIGN: Copy number alterations were examined by array-based comparative genomic hybridization analysis using an array harboring 4,361 bacterial artificial chromosome clones, and DNA methylation alterations on CpG islands of the p16, human MutL homologue 1, von Hippel-Lindau, and thrombospondin 1 genes and the methylated in tumor (MINT-1, MINT-2, MINT-12, MINT-25, and MINT-31) clones were examined in 51 clear cell renal cell carcinomas (RCC). RESULTS: By unsupervised hierarchical clustering analysis based on copy number alterations, clear cell RCCs were clustered into the two subclasses, clusters A (n=34) and B (n=17). Copy number alterations were accumulated in cluster B. Loss of chromosome 3p and gain of 5q and 7 were frequent in both clusters A and B, whereas loss of 1p, 4, 9, 13q, and 14q was frequent only in cluster B. The average number of methylated CpG islands in cluster B was significantly higher than those in cluster A. Clear cell RCCs showing higher histologic grades, vascular involvement, renal vein tumor thrombi, and higher pathologic stages were accumulated in cluster B. The recurrence-free and overall survival rates of patients in cluster B were significantly lower than those of patients in cluster A. Multivariate analysis revealed that genetic clustering was a predictor of recurrence-free survival and was independent of histologic grade and pathologic stage. CONCLUSIONS: This genetic clustering of clear cell RCC is significantly associated with regional DNA hypermethylation and may become a prognostic indicator for patients with RCC.  相似文献   
92.
In order to investigate the origin of the loop-type diuretic activity of M17055 (1), several variants (3-9) were designed and synthesized by modifying the quinolinone skeleton, and their diuretic activities were compared with the lead 1 and furosemide in dogs. It was found that the negative charge distribution pattern afforded by the dispositional arrangement of the 4-oxime-O-sulfonic acid and 1-N-acyl carbonyl moiety attached to the tetrahydropyridine ring system is inevitable for the development of the activity, which strongly supports the previously proposed model for the active site of the Na(+)-K(+)-2Cl(-) cotransporter. Also reported is the first synthesis of the dihydrothieno[3,2-b]pyridine-7(4H)-one ring system required in the synthesis of compound 9.  相似文献   
93.
PURPOSE: To evaluate the structure of the anterior segment after congenital cataract surgery with ultrasound biomicroscopy. METHODS: Ultrasound biomicroscopy was performed on 28 eyes of 15 patients after congenital cataract surgery (age range, 8-27 years; mean, 13.1 +/- 1.1 years), of which 26 eyes had pars plana lensectomy and two eyes had phacoemulsification and aspiration, and on 21 eyes of 11 phakic control subjects who were healthy (age range, 6-17 years; mean, 11.5 +/- 1.1 years). The angle-opening distance at 500 microm was measured on a line perpendicular to the trabecular meshwork 500 microm from the scleral spur, and the trabecular-iris angle was measured. RESULTS: Angle-opening distance at 500 microm in the congenital cataract group ranged from 174 to 920 microm (mean, 424 +/- 28 microm), and in the control group it ranged from 260 to 1,119 microm (mean, 643 +/- 57 microm), a difference that was significantly different (P =.0004, Student t test). The trabecular-iris angle in the congenital cataract group ranged from 30.4 to 66.9 degrees (mean, 41.9 +/- 1.6 degrees) and in the control group ranged from 32.1 to 69.8 degrees (mean, 44.9 +/- 2.5 degrees), a difference that was not significantly different (P =.28, Student t test). This means that there is a tendency for high insertion of the iris in the congenital cataract group, and intraocular pressure was elevated after surgery (including glaucoma and ocular hypertension) in 10 (47.6%) of 21 eyes with high insertion. The pars plicata after congenital cataract surgery was significantly flatter than that of control subjects (P =.0057, Student t test). CONCLUSIONS: Ultrasound biomicroscopy is a useful method for evaluating the anterior segment of eyes with congenital cataract, and complications after cataract surgery can be caused by disorganization of the anterior segment. Patients with abnormalities of the anterior segment should be followed up closely for the development of glaucoma.  相似文献   
94.
Using subtractive cloning, we identified a 1.4 kb mRNA that was ubiquitously expressed in various tissues; this mRNA was highly up-regulated in amygdala nuclei in mice when morphine was repeatedly administered but not when an opiate-receptor antagonist was co-administered. The mRNA encodes a 23 kDa protein, designated 'addicsin'. This contains two putative PKC-phosphorylation motifs and several hydrophobic regions, and was recovered in a soluble protein fraction of brain lysate. Its primary structure showed 98% identity with that of rat glutamate-transporter-associated protein 3-18 (GTRAP3-18), a putative modulator of neural glutamate-transporter EAAC1. Up-regulation of addicsin expression by morphine may affect glutamate uptake in the amygdala, causing mice to develop morphine tolerance and dependence.  相似文献   
95.
Intraperitoneal administration of fermented pine seed shell extract (PSSE) (up to 2 g/kg) induced no apparent acute toxicity to mice. Pretreatment of mice with PSSE protected them from the lethality of Escherichia coli infection. PSSE showed a very weak cytotoxic activity against both normal and tumor cells and no anti-HIV activity, but stimulated the mouse macrophage-like Raw 264.7 cells to produce nitric oxide (NO) and citrulline. ESR spectroscopy showed that PSSE produced no detectable radicals, but effectively scavenged O2- (generated by the hypoxanthine-xanthine oxidase reaction), hydroxyl radical (generated by the Fenton reaction) and NO (generated by NOC-7). Comparison of PSSE with other natural products, such as polyphenols and vitamins, further confirmed the close association between radical intensity and radical scavenging activity, suggesting the bimodal action of natural products. Although the biological activities of PSSE were relatively lower than those of other natural products, the present study suggests the possible medicinal efficacy of PSSE.  相似文献   
96.
Humans with underlying cardiovascular disease are at greater risk than humans with normal hearts for developing torsade de pointes (TdP) following exposure to some drugs that prolong ventricular repolarization. This study was designed to test the hypothesis that rabbits with ischemic myocardial failure are at similarly increased risk of developing QTc prolongation and TdP following exposure to escalating doses of drugs, which is known to have a capacity to induce TdP in humans. Coronary artery ligation was performed in 28 rabbits, causing significant (p < 0.05) reduction in left ventricular shortening fraction and systolic myocardial dysfunction 4 weeks after ligation in all operated animals compared to 38 normal, nonoperated controls. All studies were performed on rabbits anesthetized with ketamine (35 mg/kg) and xylazine (5 mg/kg). Rabbits were exposed to escalating doses of amiodarone (3, 10, 30 mg/kg/10 min), cisapride (0.10, 0.25, 0.50 mg/kg/10 min), clofilium (0.1, 0.2, 0.4 mg/kg/10 min), dofetilide (0.005, 0.01, 0.02, 0.04 mg/kg/10 min), quinidine (3, 10, 30 mg/kg/10 min), and verapamil (0.25, 0.5, 1.0 mg/kg/10 min). A greater percentage of rabbits with failing hearts developed TdP following intravenous infusion of escalating doses of dofetilide (85%), clofilium (100%), or cisapride (50%) than did normal rabbits exposed to the same drug protocol (20, 33, and 0%, respectively). None of the rabbits in either group developed TdP when exposed to escalating doses of amiodarone, verapamil, or quinidine. Two out of four test articles lengthened QTc more in rabbits with myocardial failure than in normals, and TdP occurred in 13 out of 28 rabbits with myocardial failure as opposed to only four out of 38 rabbits with normal myocardial function.  相似文献   
97.
BACKGROUND: Nutritional rickets is considered rare in developed countries. However, reports on vitamin D deficiency rickets caused by improper lifestyle have recently increased. The clinical and laboratory characteristics of patients with vitamin D deficiency rickets treated at Fukuoka Children's Hospital, Fukuoka, Japan, were evaluated to clarify current causes and ways to prevent this disease. METHODS: Clinical records were reviewed, and obtained information and data were summarized. RESULTS: Eight patients with vitamin D deficiency rickets (five boys and three girls) were treated during the past 10 years (January 1992 to December 2001). Two infants were referred to the hospital for hypocalcemia and convulsion, and six toddlers (1-2 years old) for bowlegs. One patient lacked exposure to sunlight, and six had an unbalanced diet. The cause of rickets could not be established in one patient. Anthropometric and laboratory data did not indicate malnutrition. Serum alkaline phosphatase was 2518.3 +/- 1401.7 IU/l, calcium was 8.2 +/- 2.6 mg/dL (including 4.7 mg/dL in one infant and 4.8 mg/dL in another), and phosphorus was 4.9 +/- 1.0 mg/dL. High sensitive parathyroid hormone was 1393.1 +/- 321.7 pg/mL (reference range, 180-560), 1,25-dihydroxyvitamin D was 86.0 +/- 61.5 pg/mL (reference range, 20-70), and 25-hydroxyvitamin D was 11.6 +/- 5.6 ng/mL (reference range, 10-30). The patients recovered with a change to a balanced diet, the promotion of weaning, and/or an increase in sunlight exposure. CONCLUSION: Vitamin D deficiency rickets remains a common condition that is best managed by education and disease prevention.  相似文献   
98.
Meconium disease (MD) results in intestinal obstruction in the neonate where tenacious meconium is found in the distal ileum and proximal colon. The obstructive symptoms improve at several days of age after some of the meconium is passed. We observed premature infants with MD who underwent ileostomy for intestinal obstruction due to tenacious meconium. Afterward, meconium was passed well and the clinical symptoms improved. After closing the ileostomy, growth and defecation became normal. The MD in our cases was documented by histologic changes in the maturation of ganglion cells observed at the time of ileostomy creation and closure. For an objective evaluation of the maturation of intestinal ganglion cells (IGC), we attempted to distinguish immature from mature cells by the expression of cathepsin D. We examined the distribution of cathepsin D in IGC in patients with MD to test the hypothesis that ganglion-cell immaturity might be related to MD. In ganglion cells at the time of ileostomy, cathepsin D was detected in the perinuclear cytoplasm (immature staining pattern), while at the time of ileostomy closure it was detected in intense granules throughout the cytoplasm (mature staining pattern). We propose that it would be possible to evaluate the maturation of IGC by the intracellular distribution of cathepsin D in MD and suggest that immaturity of IGC might be the cause of MD. Accepted: 28 June 1999  相似文献   
99.
Among 36 neonates with intestinal perforations (IP) between 1975 and 1996, 5 had necrotizing enterocolitis (NEC IP) and 10 had focal IPs (FIP). A histologic review of the bowel near the perforations was made to see if there was any difference between cases of NEC IP and FIP. In 1 case of NEC IP, a defect in the musculature was found in addition to disappearance of the mucosal villi and dilated vessels or hemorrhage in the submucosa. Thinning or absence of the intestinal musculature and short villi in the mucosa was observed in 3 cases of FIP, but the acute ischemic changes in FIP were much less than in NEC IP. Hypothesizing that the defective musculature in FIP may be acquired by a vascular accident either before or after birth, we examined the histology of the latest consecutive infants diagnosed as having meconium peritonitis (MP) due to in-utero volvulus and perforation. In the tissue near the perforation, there was an identical focus of thinning and interruption of the musculature while the acute ischemic changes were minimal. We speculate that thinning or absence of the intestinal musculature in FIP may be a result of a transient ischemic event occurring in-utero and that FIP may develop in the damaged intestine after birth when it is fully dilated. Accepted: 1 September 1998  相似文献   
100.
Summary Comparative ultrastructural examination and energy-dispersive electron probe X-ray microanalysis were performed on a long standing skin lesion of hemosiderotic histiocytoma. Iron-containing fine particles present in siderosome were the main element of interest. Qualitative study of spectra over the siderosomes clearly demonstrated the characteristic X-ray energy emitted by iron, whereas spectra obtained from adjacent cytoplasm revealed minimal iron peak. On quantitative evaluation of the spectra yielded from various siderosomes, iron counts intensity was found to be proportionally increased with increment in amount and electron opacity of the siderosomal inclusion. Accounts on chemical nature of the siderosomal inclusion and on the presence of lipid residue in cytoplasm were noted.Supported in part by research funds from the Japanese Dermatological Association and the Japanese Ministry of Education.  相似文献   
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