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11.
Between March 1984 and February 1991, six orthotopic liver transplantations were performed at the Chang Gung Memorial Hospital in Taiwan. The indications for transplantation were Wilson's disease (5 patients) and biliary atresia (1 patient). Donors and recipients were matched only for size and ABO blood group compatibility, and the recipient operations were performed without the use of a venovenous bypass. Arterial reconstruction was carried out by end-to-end hepatic artery anastomosis (4), thoracic aortic conduit (1), or interposition of an iliac artery graft (1), whereas biliary reconstruction was accomplished by a choledochocholedochostomy using a T-tube stent (4) or a choledochocholedochostomy using an external cholecystostomy without stenting (2). Biliary complications occurred in three patients, and all required additional surgery. The average duration of donor-liver cold ischemia, operating time, and blood loss during surgery were 7 h and 50 min (range, 4.5–9 h), 13.5 h (range, 11.8–17h), and 4,385 ml (range, 750–12,000 ml) respectively. The immunosuppressive regimens included a cyclosporinsteroid combination (n=2) and a triple-drug combination (n=4). All except one of the surviving patients experienced at least one rejection episode that was reversed by a methyl-prednisolone bolus and/or recycle. One patient developed a primary cytomegalovirus (CMV) infection that responded well to Ganciclovir treatment. Two of the patients died, one of injuries sustained in a traffic accident 3 years after transplantation, and the other of massive upper gastrointestinal bleeding. The overall survival value at 3 months was 83%, and the follow-up period ranged from 3 months to 7 years. All of the survivors have achieved complete rehabilitation and currently enjoy an excellent quality of life with normal liver function. Althought the present study involved a small number of cases, our results indicate that liver transplantation can be successfully achieved in a high proportion of patients with acceptable morbidity, mortality, and cost in an Asian setting. The extreme shortage of donor organs is currently the most important obstacle limiting the application of liver transplantation in Taiwan.Presented at The Second International Symposium on Treatment of Liver Cancer. Taipei, 3–4 February 1991  相似文献   
12.
Human renin is synthesized as an inactive zymogen (prorenin) which is processed to the active form. We synthesized an 11-amino acid peptide which spans the human prorenin processing site in order to develop a simple assay to study human prorenin activation. Six enzymes which are capable of activating recombinant prorenin in vitro were studied. Four of these enzymes digested the synthetic peptide in a specific fashion, as analyzed by reverse-phase high-performance liquid chromatography. Amino acid analysis of the purified digestion products revealed that trypsin cleaves between Arg-Leu, the authentic processing site, while kallikrein, plasmin and elastase all cleaved at alternate sites. On the other hand, pepsin and cathepsin D did not cleave this substrate, suggesting that the activation of prorenin by these proteases might occur at a site distinct from the authentic processing site. Our data suggest that this synthetic peptide may be used as a simple and specific assay for prorenin activation.  相似文献   
13.
Objective: To study the relationship between transaldolase activity, protein expression and testosterone synthesis in Leydig cells of pubertal mice. Methods: Leydig cells were cultured for 2 hours and 8 hours, to the Stimulation Group, hCG was added and to the Controls, only the vehicle. The testosterone concentration was then determined by enzyme-linked immunoadsordent assay (ELISA) and the transaldolase activity and protein expression by Western blot. Results: (1) Both the testosterone concentration and the transaldolase activity in both Stimulation Groups were significantly higher than those in the corresponding Controls (2 h: p<0.05-0.01; 8 h: P<0.001); (2) The ratios of the A isoform, the B isoform and the total transaldolase protein to β-actin between the Stimulation and Control Groups did not differ signifi-cantly. Conclusion: hCG stimulates the transaldolase activity as well as the testosterone synthesis in the Leydig cells of pubertal mice, indicating a positive relationship between them.  相似文献   
14.
15.
A genome-wide screen was conducted using a large white sample to identify QTLs for FNCS geometry. We found significant linkage of FNCS parameters to 20q12 and Xq25, plus significant epistatic interactions and sex-specific QTLs influencing FNCS geometry variation. INTRODUCTION: Bone geometry, a highly heritable trait, is a critical component of bone strength that significantly determines osteoporotic fracture risk. Specifically, femoral neck cross-sectional (FNCS) geometry is significantly associated with hip fracture risk as well as genetic factors. However, genetic research in this respect is still in its infancy. MATERIALS AND METHODS: To identify the underlying genomic regions influencing FNCS variables, we performed a remarkably large-scale whole genome linkage scan involving 3998 individuals from 434 pedigrees for four FNCS geometry parameters, namely buckling ratio (BR), cross-sectional area (CSA), cortical thickness (CT), and section modulus (Z). The major statistical approach adopted is the variance component method implemented in SOLAR. RESULTS: Significant linkage evidence (threshold LOD = 3.72 after correction for tests of multiple phenotypes) was found in the regions of 20q12 and Xq25 for CT (LOD = 4.28 and 3.90, respectively). We also identified eight suggestive linkage signals (threshold LOD = 2.31 after correction for multiple tests) for the respective geometry traits. The above findings were supported by principal component linkage analysis. Of them, 20q12 was of particular interest because it was linked to multiple FNCS geometry traits and significantly interacted with five other genomic loci to influence CSA variation. The effects of 20q12 on FNCS geometry were present in both male and female subgroups. Subgroup analysis also revealed the presence of sex-specific quantitative trait loci (QTLs) for FNCS traits in the regions such as 2p14, 3q26, 7q21 and 15q21. CONCLUSIONS: Our findings laid a foundation for further replication and fine-mapping studies as well as for positional and functional candidate gene studies, aiming at eventually finding the causal genetic variants and hidden mechanisms concerning FNCS geometry variation and the associated hip fractures.  相似文献   
16.
The tumor microenvironment consists of tumor, immune, stromal, and inflammatory cells which produce cytokines, growth factors, and adhesion molecules that promote tumor progression and metastasis. Of particular interest in this setting is interleukin-1 (IL-1), a pleiotropic cytokine with numerous roles in both physiological and pathological states. It is known to be up regulated in many tumor types and has been implicated as a factor in tumor progression via the expression of metastatic and angiogenic genes and growth factors. A number of studies have reported that high IL-1 concentrations within the tumor microenvironment are associated with a more virulent tumor phenotype. Solid tumors in which IL-1 has been shown to be up regulated include breast, colon, lung, head and neck cancers, and melanomas, and patients with IL-1 producing tumors have generally bad prognoses. The exact mechanisms by which IL-1 promotes tumor growth remain unclear, though the protein is believed to act via induction of pro-metastatic genes such as matrix metalloproteinases and through the stimulation of adjacent cells to produce angiogenic proteins and growth factors such as VEGF, IL-8, IL-6, TNFα, and TGFβ. The IL-1 receptor antagonist (IL-1ra) is a naturally occurring inhibitor to IL-1 and acts by binding to the IL-1 receptor without activating it. The protein has been shown to decrease tumor growth, angiogenesis, and metastases in murine xenograft models. Our focus in this review is to summarize the known data on the role of IL-1 in tumor progression and metastasis and the use of IL-1 inhibition as a novel therapeutic approach in the treatment of solid organ malignancies.  相似文献   
17.
心脏穿透伤是心胸外科的特急重症,占到胸部外伤的 2%~396,据报道院外死亡率为62%~8496,入院后死亡率为15%,且有日益增高的趋势。我科1998年9月- 2005年4月共收治心脏穿透伤18例,取得一定的救护经验, 现报道如下。  相似文献   
18.
BACKGROUND: This study investigated the utility of the alveolar - arterial oxygen pressure difference (AaDO (2)) in predicting the short-term prognosis of acute pulmonary embolism (PE). METHODS AND RESULTS: This study retrospectively enrolled 114 consecutive patients with acute PE, diagnosed by either spiral computed tomography or high probability ventilation - perfusion lung scans. During the first 24 h of admission, all patients had initial artery blood gas collected under room air. Patient exclusion criteria were chronic lung disease, septic emboli, and moderate and low probability lung scans. Patients were assigned to 2 groups based on either 30-day death or a 30-day composite event. Receiver operating characteristic analyses was used to determine the AaDO(2) cut-off value for predicting primary and composite endpoints. Statistical analysis demonstrated significant differences in AaDO(2) between the 30-day composite endpoint group and the 30-day composite event-free survival group (p=0.012). The AaDO(2) had a strong trend between the 30-day death group and the survival group (p=0.062). The best cut-off value for AaDO(2) was 53 mmHg and using this, the positive predictive value for 30-day death was 25% and the negative predictive value was 92%. For the 30-day composite endpoint, the positive predictive value for AaDO(2) was 35%, and the negative predictive value was 84%. In this study, thrombocytopenia was also an indicator of poor prognosis for patients with acute PE. CONCLUSION: The AaDO(2) measurement is a highly useful and simple measurement for predicting short-term prognosis in patients with acute PE. It has high negative predictive value and moderate positive predictive value for 30-day death and 30-day composite event. Aggressive thrombolytic treatment strategies should be considered for patients with an initial poor prognostic parameter (ie, AaDO(2) >or=53 mmHg).  相似文献   
19.
脱细胞尿道及其海绵体基质制备的实验研究   总被引:1,自引:0,他引:1  
目的 探索脱细胞尿道及其海绵体基质的制备方法。方法取健康壮年兔完整尿道及其海绵体组织,以Triton-X100与NH3H2O联合提取法进行脱细胞处理。标本做HE染色,组织学观察分析脱细胞效果。结果脱细胞处理11天后,成功获得脱细胞及其海绵体基质,所得基质外观良好。HE染色观察无细胞存在。弹力纤维排列规整,间隙较大,结构无破坏。结论利用Triton-X100与NH3H2O联合提取法可成功制备完整无细胞尿道及其海绵体基质,为尿道再造修复提供崭新思路。  相似文献   
20.
BACKGROUND AND PURPOSE: The potential risk of prolongation of treatment time in cervical cancer has been reported for many low-dose rate (LDR) studies, with an estimated loss of local control ranging from 0.3 to 1.6% per day of treatment prolongation. Since the treatment schedule for fractionated high-dose rate intracavitary brachytherapy (HDRICB) is not directly comparable with that for low-dose rate studies, this report aims to evaluate the adverse effect of treatment prolongation specifically for cervical cancer treated with HDRICB. MATERIAL AND METHODS: From September 1992 to December 1997, 257 patients diagnosed with uterine cervical cancer (35 Ib, 26 IIa, 122 IIb, 10 IIIa, 57 IIIb, 7 IVa), who underwent external radiotherapy combined with between two and four courses of HDRICB and a minimum of 3 years of follow-up (median 57 months), were analyzed. Treatment consisted of irradiation of the whole pelvis with 44-45 Gy consisting of 22-25 fractions by 5 weeks, with the dose boosted to 54-58 Gy (with central shielding) for patients diagnosed as FIGO stage IIb-IVa bilateral parametrial disease. HDRICB was performed using an Ir-192 remote afterloading technique at 1-week intervals. The standard prescribed dose for each course of HDRICB was 7.2 Gy to point A for three insertions (before July 1995), or 6.0 Gy to point A for four insertions (after July 1995). Total prescribed point A doses (external beam radiotherapy+HDRICB) ranged from 58 to 71.6 Gy (median, 65.6 Gy) for stage IB-IIA, while analogous dosage for larger lesions (stage IIb-IVa) ranged from 59 to 75.6 Gy (median, 65.6 Gy). Kaplan-Meier and multivariate analyses were used to test the effect of treatment time on pelvic control rate (PCR) and cause-specific survival (CSS) at 5 years. RESULTS: Median treatment time was 63 days. For all stages of disease, the 5-year CSS and PCR were significantly different comparing treatment times of less than and greater than or equal to 63 days [83% and 65% (P=0.004], 93% and 83% (P=0.02), respectively]. These associations were also significant for stage Ib/IIa [97% and 79% (P=0.01), and 100% and 87% (P=0.02), respectively), but not for stage IIb [75% and 72% (P=0.79), and 93% and 87% (P=0.83), respectively] or stage III [66% and 49% (P=0.2), and 83% and 72% (P=0.21), respectively]. Multivariate analysis identified three prognostic factors for CSS, stage (P<0.001), tumor response to external RT (P=0.001), and overall treatment time (OTT; P=0.006). Prognostic factors for pelvic failure were stage (P<0.001), tumor response to external RT (P=0.001), and OTT (P=0.03). Prolongation of treatment time resulted in a daily decrease in pelvic control rate of 0.67% overall, and 0.43% for stage Ib-IIa, 0.57% for stage IIb, and 0.73% for stage III patients. CONCLUSION: Analysis of the data from the current study demonstrates that the adverse effect of treatment prolongation was observed later in the treatment course for the high-dose rate (HDR) series compared to the LDR analog, however, treatment-time prolongation still negatively influenced the cause-specific survival and pelvic control rate for both dosage groups.  相似文献   
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