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991.
992.
The extent of donor hepatectomy may affect splenic hypertrophy and platelet count. The subjects were 50 live liver donors. The ratio of the graft weight to total liver volume (GW/TLV) and the splenic hypertrophy ratio, expressed as the splenic volume one month after surgery divided by that before surgery, were calculated. The platelet count one month after surgery was divided by that before surgery to determine the rate of the platelet count decrease. The correlation of GW/TLV to the splenic hypertrophy ratio and the rate of the platelet count decrease were examined. The median (range) GW/TLV was 54 (28-71)%. The splenic hypertrophy ratio and the rate of the platelet count decrease was 133 (99-191)% and 92 (71-129)%, respectively. GW/TLV positively correlated with the splenic hypertrophy ratio (Spearman's correlation coefficient (r(s)) = 0.448, p = 0.001), and negatively correlated with the rate of the platelet count decrease (r(s) = -0.471, p < 0.001). Multivariate analysis revealed that GW/TLV influenced the splenic hypertrophy ratio [adjusted odds ratio (OR), 12.0; 95% confidence interval (CI), 1.32-9.04; p = 0.01] and the ratio of the platelet count decrease (adjusted OR, 11.6; 95% CI, 1.40-8.33; p = 0.01). Larger graft procurement might place living liver donors at higher risk for post-operative thrombocytopenia.  相似文献   
993.
From April to December 2002, 40 patients underwent coronary artery bypass grafting (CABG) using the St. Jude Medical (Minneapolis) Symmetry bypass system (aortic connector system: ACS). 59 proximal anastomoses (51 saphenous vein grafts, 8 radial artery grafts) were performed with the ACS. One saphenous vein graft occluded during operation. Postoperative evaluation of the anastomotic patency was carried out by angiography in 45 grafts. Five of the saphenous vein grafts were occluded (5/38). One patient who was shock state before operation presented with postoperative unconsciousness. Another patient died at 8th postoperative day caused by ventricular fibrillation. We conclude that the ACS produces a simple, quick way of performing the proximal anastomosis without the need for clamping the aorta, allows reducing risk of embolization by aortic manipulation. However, it is necessary to discuss sufficiently using the ACS, because the graft patency with the ACS is lower than with standard suturing technique.  相似文献   
994.
To elucidate the central mechanisms of sound segregation, we compared responses to a harmonic sound and a mistuned sound using a whole-head magnetoencephalography system. The harmonic sound was composed of a 200-Hz tone and its 2nd to 12th harmonics. The mistuned sound had, instead of the 600-Hz harmonic, a 696-Hz tone. In the right hemisphere, the amplitude of N100m responses evoked by the mistuned sound was significantly larger and the peak latency significantly longer than that evoked by the harmonic sound, suggesting that the right hemisphere plays a more important role than the left in detecting mistuned partials.  相似文献   
995.
OBJECTIVE: To clarify the mechanism of congenital mirror movements. DESIGN: The triple stimulation technique (TST) and the silent period were used to investigate a patient with congenital mirror movements. The TST was used to calculate the ratio of ipsilateral to contralateral corticospinal tracts from the two hemispheres to the spinal motor neurones. RESULTS: Transcranial magnetic stimulation over unilateral M1 induced larger ipsilateral than contralateral motor evoked potentials on both sides. Only 9% of spinal motor neurones innervating the abductor digitorum minimi were excited by contralateral primary motor cortex (M1) stimulation, while 94% were excited by the ipsilateral M1 stimulation. The silent period was examined during mirror movements and with voluntary contraction of the right first dorsal interosseus mimicking mirror movements. Left M1 stimulation (through the crossed corticospinal tract) did not show any difference in silent period between the two conditions, while right M1 stimulation (through the uncrossed tract) caused a longer silent period during mirror movements than during voluntary contractions. CONCLUSIONS: The results suggest that mirror movements may be caused by a strong connection between ipsilateral M1 and the mirror movements conveyed through a dominant ipsilateral corticospinal pathway.  相似文献   
996.
997.
Some studies have shown reduced portal blood flow in patients with occult hepatic metastases, which may lead to decreased liver volume. A retrospective study was conducted in patients undergoing curative resection for colorectal (n = 63) or gastric (n = 52) cancer. The ratio of the preoperative computed tomography (CT)-estimated liver volume to the standard liver volume (CV/SV ratio) was calculated. The mean ± SD CT-estimated liver volume was 858 ±109 in 14 patients who subsequently developed hepatic metastases and 1173 ± 230 ml in 101 patients without metastases (p < 0.0001). The CV/SV ratio was smaller in patients with metachronous hepatic metastases than in those without (0.78 ± 0.08 vs. 1.02 + 0.13; p < 0.0001). The results suggest that the liver with occult metastases decreases in size before metastases develop that are detectable using conventional imaging techniques. The CV/SV ratio may be of value in detecting occult hepatic metastases from colorectal and gastric cancer.  相似文献   
998.
Intrahepatic cholangiocarcinoma (IHCC) is a rare primary hepatic tumor. Outcomes after resection and the use of lymph node dissection have not been well described. From a prospective database, we identified 53 patients with IHCC who underwent exploration between April 1983 and March 2004. Hepatic resection was performed in 44 patients, 30 of whom underwent lymph node dissection. Clinicopathological features and outcomes were analyzed. The actuarial 1-year survival was 66.2% in resected patients, compared to 0% in unresectable patients (p < 0.0001), with a 50% overall survival of 21.5 months and 3.1 months, respectively. The actuarial 3-year and 5-year overall survival rates in resected patients were 38.3% and 26.3%, respectively. Univariate analysis revealed that factors associated with poor overall survival included multiple tumors, extrahepatic bile duct involvement, noncurative resection, and involvement of lymph nodes. Multivariate analysis in resected patients revealed that multiple tumors (p < 0.0074) and non-curative resection (p = 0.0068) were significant risk factors for poor overall survival. The survival rate in patients with three or more positive nodes was significantly lower than in those with fewer than three (p < 0.0001). Three patients with solitary tumors and one or two involved lymph nodes have survived beyond 4 years after extended lobectomy with systemic lymphadenectomy. Curative resection, single tumor, and fewer than two lymph node metastases were prognostic factors for good outcome. Curative resection with lymph node dissection improved survival in patients with no more than two positive lymph nodes.  相似文献   
999.
BACKGROUND: Lysis-deficient (LyD) bacteriophages (phages) kill bacteria without endotoxin (Et) release. This may minimize systemic cytokine responses and limit inflammation in bacterial sepsis. We determined the effects of t amber A3 T4 LyD and virulent wild-type (WT) phages on mouse bacterial peritonitis. METHODS: Balb/c mice were injected with B40sul Escherichia coli, treated intraperitoneally with LyD, WT, or a beta-lactam antibiotic [latamoxef sodium (LMOX)], and followed for survival. We measured Et release, tumor necrosis factor (TNF)-alpha and interleukin (IL)-6, as well as bacterial counts and peritoneal exudative cells (PECs) in peritoneal lavage fluid at 6 and 12 hours after infection. RESULTS: LyD mice showed significantly greater survival compared with other groups. Et levels were significantly lower in the LyD mice at 6 and 12 hours after infection. TNF-alpha and IL-6 levels were lower in LyD mice compared with control (untreated) mice at 12 hours. Compared with controls, bacteria counts in peritoneal lavage fluid were lower in all treatment groups (LyD, WT, or LMOX) at 6 and 12 hours. PEC counts were highest in LyD mice at 6 hours but significantly lower than that in WT phage- and LMOX-treated mice at 12 hours. CONCLUSIONS: LyD phage therapy significantly improves survival and attenuates the systemic effects of bacterial sepsis by minimizing Et release and pro-inflammatory mediators in murine bacterial peritonitis. Further studies may find phage therapy useful in treating peritonitis and multidrug-resistant bacterial infections.  相似文献   
1000.
Human beta-defensins (hBDs), which are mainly expressed in epithelial tissues, may contribute to infection-protective mechanisms in the ocular surface. We examined hBD1 and hBD2 expression in the ocular surface by RT-PCR and immunohistochemistry and studied the effects of immunosuppressive agents on their expression in human corneal epithelial cells in vitro. mRNA expression of hBD1 and hBD2 was confirmed in corneal epithelial cells. While the hBD1 peptide was immunohistochemically detected in corneal, limbal, and conjunctival epithelium, the level of expression was stronger in limbal- and conjunctival- than in corneal epithelium. Very weak expression of the hBD2 peptide was detected only in corneal epithelium. After 48-h culture of human corneal epithelial cells in the presence of 10(-5) M dexamethasone or 1 mg l(-1) cyclosporin A, total RNA was extracted and hBD1 and hBD2 mRNA expressions compared using semi-quantitative RT-PCR and introduced amplified fragment length polymorphism (iAFLP) assay. The two methods yielded almost identical results. hBD1 mRNA expression was not changed by dexamethasone but was down-regulated by cyclosporin A. hBD2 mRNA expression was up-regulated by dexamethasone and down-regulated by cyclosporin A. Our findings suggest that hBD1 and hBD2 are regulated by different mechanisms and that hBD1 may contribute to infection-protective mechanisms in the relatively immunosuppressed status induced by dexamethasone.  相似文献   
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