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91.
To improve low-pitched voices in cases with polypoid vocal cords, YAG laser irradiation combined with a mucosal suturing technique was attempted in 9 female cases with severe polypoid changes in their vocal cords. A YAG laser beam (5 to 10 W) was used to irradiate the upper surface of the polypoid vocal cord. The polypoid content of the cord was gradually coagulated, and the free edge of the cord appeared to slide up toward the burned area. The polypoid content was then removed and squeezed through an open wound made in the burned area using a conventional method. Bleeding was successfully controlled using the laser. After the excessive mucosal margin was trimmed and the contour of the vocal cord was adjusted, the wound was closed by 7-0 monofilament absorbable suture. Suturing was relatively easy because the mucosal edge was also coagulated. Postoperative evaluations of voice quality revealed an improvement in the GRBAS scale of voice quality as well as an elevation in voice pitch and an upwards shift in the voice range in all cases.  相似文献   
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93.
In this study, we analyzed the extent and pattern of regression of left ventricular (LV) hypertrophy after aortic valve replacement in patients with aortic stenosis (AS) and compared the results with those of another group of patients with aortic regurgitation (AR). Seventy patients who underwent isolated aortic valve replacement were divided into 2 groups. Group 1 was comprised of 29 patients who underwent aortic valve replacement for aortic stenosis, and Group 2 of 41 patients who underwent aortic valve replacement for aortic regurgitation. A third group of 10 healthy subjects served as a healthy control group. Echocardiographic studies were done before the operation and 5 years postoperatively. At follow-up, a significant reduction in the left ventricular mass was found in both groups, but it remained significantly greater than in the healthy control group. The ratio of LV wall thickness to radius (th/r) in Group 1 decreased significantly, and at follow-up it was within the normal value. In Group 2, the th/r ratio increased, and at follow-up it was within the normal value. After aortic valve replacement, the wall thickness remained significantly greater than normal for patients with AS, and the chamber radius remained significantly greater than normal for patients with AR. For these reasons, LV hypertrophy still existed in both groups at postoperative follow-up. The actuarial survival rate was 85.3% at 16 years for Group 1 and 83.4% at 18 years for Group 2. There was no significant difference in the long-term survival rates between the 2 groups. Actuarial freedom from valve-related events was 91.9% at 16 years for Group 1 and 82% at 18 years for Group 2. There was no significant difference in the valve-related event free curves between groups. After 5 years of follow-up, th/r reached normal for both groups, indicating remodeling of the LV geometry after aortic valve replacement.  相似文献   
94.
95.
PURPOSE: T helper (Th) 1/Th2 balance, controlled by Th1 or Th2 cells producing cytokines, plays important roles in antitumor immunity. Interleukin-18 (IL-18) can act together with IL-12 in promoting the generation of IFN-gamma producing Th1 cells. The goal of this study was to determine whether cytotoxic T lymphocyte (CTL) secreted in a murine IL-18-induced Th1-dominant state inhibited the development of primary tumors and synchronous liver metastases in orthotopic colon cancer model. EXPERIMENTAL DESIGN: Murine IL-18 gene was transduced into activated T lymphocytes by an adenovirus vector encoding IL-18 (AdIL-18) liposome complex method. Efficacy of adoptive immunogene therapy using AdIL-18 with or without IL-12 was tested in advanced orthotopic xenograft of murine colon cancer. To elucidate the mechanism responsible for the adoptive immunogene therapy, serum IL-4, IL-6, IFN-gamma, and tumor necrosis factor alpha production in Th1/Th2 cytokine balance and quantification of tumor vascularity were investigated. RESULTS: By a modified method of adenoviral gene transduction, T lymphocytes achieved efficient IL-18 production without cell toxicity. Against orthotopic colon cancer, when combined with low dose of recombinant (r) IL-12 (AdIL-18-CTL/rIL-12), the therapeutic efficacy showed much smaller tumors with no liver metastases and no disseminated tumors. There was a significant difference in the volume of primary tumors and the number of liver metastases compared with the group treated with AdIL-18-CTL alone or other group (P < 0.01). In addition, the median survival time of the group treated with AdIL-18-CTL was 53.7 +/- 5.8 days and that of AdIL-18-CTL/rIL-12 was 78.4 +/- 6.1 days, which was also a significant difference (P < 0.01). These antitumor mechanisms were involved with Th1-dominant response in serum Th1/Th2 cytokine balance and suppression of neovascularization at primary tumor site. CONCLUSION: These data suggest that a strategy of Th1/Th2 balance-based adoptive immunogene therapy might be useful for advanced cancer patients.  相似文献   
96.
Background Deletions involving chromosome 9p21, on which the tumor suppressor genep16/MTS1 is located, have been noted in esophageal cancer. We investigated the relationship between the deletion of chromosome 9p21–22 and the clinical features of esophageal cancer. Methods We examined the loss of heterozygosity (LOH) on chromosome 9p21–22 in 56 esophageal cancers using polymerase chain reaction (PCR) analysis and 2 microsatellite markers (RPS6 and IFNA). Results In 18 out of 50 informative cases (36%), LOH had occurred at 1 or 2 loci on chromosome 9p21–22. We found no relationship between LOH on chromosome 9p21–22 and patient sex, age tumor length, location, histologic differentiation, depth of tumor invasion, the extent of lymph node metastasis, histologic stage, or curability. Among 35 patients without an absolute noncurative resection, the mean survival of 11 patients with LOH on chromosome 9p21–22 was 19.3 months, compared with 42.3 months for 24 patients with a normal allele; thus, the survival rate of those with LOH was significantly lower than that of patients without LOH on chromosome 9p21–22 (log-rank test;P=0.03). Conclusion These data suggest that LOH on chromosome 9p21–22, on which the cell-cycle regulatorp16/MTS1 gene is located, may be related to cancer development, and probably can serve as a clinical marker for evaluating a patient's prognosis.  相似文献   
97.
BACKGROUND: Several researchers reported promising results that local excision with or without postoperative chemo-radiation therapy is an alternative approach for sphincter preservation in patients with locally invasive rectal carcinomas. However, indications and long-term results have not yet been determined. METHODS: Demographic and pathological characteristics of eight patients with locally invasive tumors undergoing initially local excision were reviewed with reference to histological features at the invasive margin. RESULTS: All the tumors were well differentiated adenocarcinomas. In all but two tumors, the invasion was limited within the proper muscle layer. Radiation therapy was given preoperatively in one patient and postoperatively in two patients. Additional bowel resection was not attempted in these three cases. Among the remaining five patients, two received additional bowel resection with lymph node dissection. No lymph node metastasis was observed in these two patients. During the average follow-up period of 55 months, three patients had regional lymph node metastases at 7, 36 and 72 months, respectively. Another patient had regional lymph node and distant metastases at 5 months. Three out of five patients with moderate to severe grade of dedifferentiated histology at the invasive margin (H-inv) had regional lymph node metastases. On the other hand, one out of three patients with mild H-inv had lymph node metastases. CONCLUSIONS: H-inv may be useful as a clinical predictor of lymph node metastasis. However, more experience is needed to confirm the usefulness of H-inv in selecting invasive rectal cancer patients in whom local excision is safe and appropriate.   相似文献   
98.
To determine whether bucolome (5-n-butyl-1-cyclohexyl-2,4,6-trioxoperhydropyrimidine), a nonsteroidal anti-inflammatory agent, can reverse diuretic resistance of furosemide in patients with nephrotic syndrome, we examined the inhibitory effect of bucolome on the protein binding of furosemide in serum and urine. Bucolome significantly inhibited the protein binding of furosemide not only in serum but also in urine of preparation albumin (UPA), which mimics urinary albumin concentration in patients with nephrotic syndrome by ultrafiltration method. The binding percentage of furosemide to albumin was approximately 70% in UPA. With coadministration of bucolome to healthy volunteers, renal clearance of furosemide was increased, reflecting the increase of the free fraction of furosemide in serum. Furthermore, coadministration of bucolome caused a significant increase of urine volume and sodium concentration in urine. Even at higher urine levels of furosemide, the inhibitory effect of bucolome on the protein binding of furosemide in UPA remains constant, and changes in pH at weakly acidic pH levels (pH 5.5-6.5) did not alter the inhibitory effect of bucolome. Interestingly, coadministration of bucolome with furosemide in doxorubicin (Adriamycin)-induced nephrotic syndrome model rats alleviated the diuretic resistance. These results suggest that bucolome has a potent inhibitory effect on the protein binding of furosemide in the urine and can partially restore the diuretic response of furosemide in patients with nephrotic syndrome by increasing the free fraction of furosemide at the site of action.  相似文献   
99.
Recently, we demonstrated that some A-ring-modified vitamin D3 analogs had unique biological activity. Of these analogs, 2alpha-propoxy-1alpha,25(OH)2D3 (C3O1) and 2alpha-(3-hydroxypropoxy)-1alpha,25(OH)2D3 (O2C3) were examined for metabolism by CYP27A1 and CYP24A1. Surprisingly, CYP27A1 catalyzed the conversion from C3O1 to O2C3, which has 3 times more affinity for vitamin D receptor than C3O1. Thus, the conversion from C3O1 to O2C3 by CYP27A1 is considered to be a metabolic activation process. Five metabolites were detected in the metabolism of C3O1 and O2C3 by human CYP24A1 including both C-23 and C-24 oxidation pathways. On the other hand, three metabolites of the C-24 oxidation pathway were detected in their metabolism by rat CYP24A1, indicating a species-based difference in the CYP24A1-dependent metabolism of C3O1 and O2C3 between humans and rats. Kinetic analysis revealed that the Km and kcat values of human CYP24A1 for O2C3 are, respectively, approximately 16 times more and 3 times less than those for 1alpha,25(OH)2D3. Thus, the catalytic efficiency, kcat/Km, of human CYP24A1 for O2C3 is only 2% of 1alpha,25(OH)2D3. These results and a high calcium effect of C3O1 and O2C3 in animal experiments using rats suggest that C3O1 and O2C3 are promising for clinical treatment of osteoporosis.  相似文献   
100.
To examine the role of c-Jun N-terminal kinase (JNK/SAPK) in the developing nervous system of vertebrates, the localization of an active form of JNK, phosphorylated JNK (p-JNK), was studied in the lumbosacral spinal cord of the chick embryo. We also examined the localization of phosphorylated neurofilaments (NFs, potential targets of p-JNK) and cyclin-dependent kinase 5 (Cdk5), which is known to phosphorylate cytoskeletal proteins, including NFs, and compared their expression with that of p-JNK. Additionally, the localization of phosphorylated forms of c-Jun and ATF-2 was compared with that of p-JNK. On embryonic day 3 (E3), the expression of p-JNK was observed in regions containing early-projecting axons. Axons in these regions also expressed phosphorylated NFs. Subsequently, on E5 and E8, the expression of both p-JNK and phosphorylated NFs increased concomitantly in the axonal tracts in the spinal white matter. Thus, white matter expressed both p-JNK and phosphorylated NFs, whereas there was only weak expression of Cdk5. By E13, the spinal cord expression pattern of p-JNK and phosphorylated NFs had changed compared to earlier ages. Although phosphorylated NFs were still expressed in the white matter, the expression of p-JNK was decreased in axons in the white matter, whereas strong p-JNK expression appeared in cell nuclei in the gray matter. In summary, the present study revealed that the localization of p-JNK in the spinal cord changes dramatically from axons to cell nuclei during development, suggesting multiple roles of p-JNK, depending on the developmental age.  相似文献   
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