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The aim of the study was to prove the long-lasting and continuously harmful effect of chronic Chlamydia pneumoniae (CPn) infection on vessel walls in patients with diffuse coronary artery disease (CAD). In surgically obtained endarterectomized atherosclerotic plaques grade VI-VIII (Stary classification) from 10 patients with diffuse coronary artery disease and chronic (7) or past (3) CPn infection, signs of inflammatory response of the vessel wall on infectious agents were studied. In all 10 endarterectomized plaque step serial sections, immunologic signs of vessel wall response were present (positive T- and B-lymphocytes, macrophages, and capillarogenesis). In 8 of 10 patients' atherosclerotic plaque, unique features of active vasculitis in the neoarteriolar wall as well as arteriologenesis, were found. Seven of these 8 patients had serologically proven chronic CPn infection, and 1 had past infection. Features of vasculitis as well as arteriologenesis were absent in 2 patients who recovered from CPn infection at the time of surgery. In the endarterectomized segments of 3 randomly chosen patients in this study, the polymerase chain reaction method revealed positive DNA of CPn. Two of these patients had chronic infection, but the third had only a past CPn infection. This study provides evidence that CPn infection has continuous and a long-lasting inflammatory response in the high-grade atherosclerotic coronary artery vessel wall.  相似文献   
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Endometrial biopsies were obtained from 12 volunteers treated with d-norgestrel-releasing intrauterine devices (IUDs) with two different release rate. Four subjects scheduled for hysterectomy had d-norgestrel-releasing IUDs inserted approximately 1 month prior to surgery. The effect of d-norgestrel on the endometrium and fallopian tubes of the removed uteri was examined. A uniform suppression of the endometrium with glandular atrophy and decidualization of the stroma was found in all of the endometrial specimens. Moreover, changes similar to those observed during the luteal phase and early pregnancy could be seen in the tubal epithelium.  相似文献   
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Tumor progression and recurrence of cervical cancer is associated with upregulation of matrix metalloproteinase 2 (MMP-2). We evaluated the location, origin and activity of MMP-2 in cervical squamous cell carcinomas in comparison with MT1-MMP (MMP-14), TIMP-2 and extracellular matrix metalloproteinase inducer (EMMPRIN). Positive immunostaining for MMP-2 in malignant cells was detected in 83% of the patients. Two patterns of tumor cell MMP-2 staining were observed: either homogenous in all tumor cells or confined to the cells neighboring the stroma (tumor-border staining pattern, TBS). Fluorescence in situ zymography showed active MMP-2 mainly around tumor nodules displaying TBS. The MMP-2 staining of TBS tumors correlated significantly with the presence of TIMP-2 and MT1-MMP, proteins involved in docking MMP-2 to the cell surface and essential for MMP-2 activation. In situ mRNA hybridization in TBS tumors demonstrated more abundant presence of MMP-2 mRNA in neighboring myofibroblasts than in the adjacent tumor cells. Moreover, the TBS MMP-2 pattern correlated with the presence of EMMPRIN (p = 0.023), suggesting that tumor cells induce MMP-2 production in nearby stromal cells. This pro-MMP-2 could subsequently be activated on tumor cells via the presence of MT1-MMP and TIMP-2. The biological relevance of this locally activated MMP-2 was underscored by the observation that only the TBS pattern of MMP-2 significantly correlated with decreased survival. In conclusion, the colocalization of EMMPRIN, MT1-MMP and TIMP-2 in human cervical carcinomas seems to be involved in a specific distribution pattern of tumor cell bound MMP-2, which is related with local proteolytic activity and therefore might be associated with worse prognosis of the patients.  相似文献   
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Zarins CK  Crabtree T  Bloch DA  Arko FR  Ouriel K  White RA 《Journal of vascular surgery》2006,44(5):920-29; discussion 929-31
OBJECTIVE: The appropriate size threshold for endovascular repair of small abdominal aortic aneurysms (AAA) is unclear. We studied the outcome of endovascular aneurysm repair (EVAR) as a function of preoperative aneurysm diameter to determine the relationship between aneurysm size and long-term outcome of endovascular repair. METHODS: We reviewed the results of 923 patients treated in a prospective, multicenter clinical trial of EVAR. Small aneurysms were defined according to two size thresholds of 5.5 cm and 5.0 cm. Two-way analysis was used to compare patients with small aneurysms (<5.5 cm, n = 441) to patients with large aneurysms (> or =5.5 cm, n = 482). An ordered three-way analysis was used to compare patients with small AAA (<5.0 cm, n = 145), medium AAA (5.0 to 5.9 cm, n = 461), and large AAA (> or =6.0 cm, n = 317). The primary outcome measures of rupture, AAA-related death, surgical conversion, secondary intervention, and survival were compared using Kaplan-Meier estimates at 5 years. RESULTS: Median aneurysm size was 5.5 cm. The two-way comparison showed that 5 years after EVAR, patients with small aneurysms (<5.5 cm) had a lower AAA-related death rate (1% vs 6%, P = .006), a higher survival rate (69% vs 57%, P = .0002), and a lower secondary intervention rate (25% vs 32%, P = .03) than patients with large aneurysms (> or =5.5 cm). Three-way analysis revealed that patients with small AAAs (<5.0 cm) were younger (P < .0001) and were more likely to have a family history of aneurysm (P < .05), prior coronary intervention (P = .003), and peripheral occlusive disease (P = .008) than patients with larger AAAs. Patients with smaller AAAs also had more favorable aortic neck anatomy (P < .004). Patients with large AAAs were older (P < .0001), had higher operative risk (P = .01), and were more likely to have chronic obstructive pulmonary disease (P = .005), obesity (P = .03), and congestive heart failure (P = .004). At 5 years, patients with small AAAs had better outcomes, with 100% freedom from rupture vs 97% for medium AAAs and 93% for large AAAs (P = .02), 99% freedom from AAA-related death vs 97% for medium AAAs and 92% for large AAAs (P = .02) and 98% freedom from conversion vs 92% for medium AAAs and 89% for large AAAs (P = .01). Survival was significantly improved in small (69%) and medium AAAs (68%) compared to large AAAs (51%, P < .0001). Multivariate Cox proportional hazards modeling revealed that aneurysm size was a significant independent predictor of rupture (P = .04; hazard ratio [HR], 2.195), AAA-related death (P = .03; HR, 2.007), surgical conversion (P = .007; HR, 1.827), and survival (P = .001; HR, 1.351). There were no significant differences in secondary intervention, endoleak, or migration rates between small, medium, and large AAAs. CONCLUSIONS: Preoperative aneurysm size is an important determinant of long-term outcome following endovascular repair. Patients with small AAAs (<5.0 cm) are more favorable candidates for EVAR and have the best long-term outcomes, with 99% freedom from AAA death at 5 years. Patients with large AAAs (> or =6.0 cm) have shorter life expectancy and have a higher risk of rupture, surgical conversion, and aneurysm-related death following EVAR compared to patients with smaller aneurysms. Nonetheless, 92% of patients with large AAAs are protected from AAA-related death at 5 years. Patients with AAAs of intermediate size (5 to 6 cm) represent most of the patients treated with EVAR and have a 97% freedom from AAA-related death at 5 years.  相似文献   
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Six components used in vaginal tampons were tested for their effects on a strain of Neisseria gonorrhoeae isolated from a patient with disseminated infection. Tampon components containing carboxymethyl cellulose or its derivative prolonged the in-vitro survival of gonococci and, when injected with mucin into mice, significantly (P less than 0.0001) increased the dissemination of gonococci from the peritoneal cavity. In contrast, a component extracted from rayon tampons reduced in-vitro survival and appeared to suppress gonococcal dissemination in mice. Since tampons are used by a large number of women at a time when the risk of developing complications from venereal infections are increased, their effects on potential urogenital pathogens warrant further study.  相似文献   
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