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71.
Guo-Wei Ma Martin Pytel Ana Luisa Trejos Victoria Hornblower Jennifer Smallwood Rajni Patel Aaron Fenster Richard A Malthaner 《Computer aided surgery》2007,12(5):270-277
OBJECTIVE: Interstitial brachytherapy is becoming an accepted treatment option for lung cancer patients for whom surgery poses a high risk. Robotic surgery has the potential to deliver brachytherapy seeds into tumors while keeping surgeons at a safe distance from the radioactive source. Our aim was to compare the accuracy, number of attempts, and time needed to place seeds next to a target when using a manual technique, video-assisted thoracoscopic surgery (VATS), and the ZEUS robot for minimally invasive surgery (MIS). METHODS: A brachytherapy seed injector was developed and attached to one of the ZEUS robotic arms. Four subjects each inserted inactive dummy brachytherapy seeds into clear agar-gelatin cubes containing a 1.6-mm stainless steel ball target. Two orthogonal radiographs were taken of each agar cube, and the corresponding distances were measured in triplicate using ImageJ processing software. The mean distance between the center of each seed and the corresponding target was calculated using the Pythagorean theorem. Comparisons were made using analysis of variance, t-tests, and Kruskal-Wallis tests, as appropriate. RESULTS: A total of 384 tests (128 for each technique) were performed. The median accuracies for the manual technique, VATS, and ZEUS were 1.8 mm (range: 0.9-6.7 mm), 2.4 mm (range: 1.0-11.3 mm), and 3.6 mm (range: 1.3-16.7 mm), respectively (p < 0.01). The median numbers of attempts for the manual technique, VATS, and ZEUS were 1 (range: 1-5), 4 (range: 1-14), and 3 (range: 1-20), respectively (p < 0.01). The median times for the manual technique, VATS, and ZEUS were 3.0 s (range: 1-43 s), 86.5 s (range: 6-372 s), and 64.5 s (range: 5-356 s), respectively (p < 0.01). CONCLUSIONS: The manual technique is the most accurate, least traumatic, and fastest method of inserting seeds into tumors. The ZEUS robotic platform was able to place seeds beside a target within a clinically acceptable distance, with an acceptable amount of trauma and time required. It achieved results equal to or better than those obtained with VATS. 相似文献
72.
阿奇霉素替代激素治疗婴幼儿喘息性支气管炎临床研究 总被引:6,自引:0,他引:6
目的评价阿奇霉素治疗婴幼儿喘息性支气管炎的疗效并探讨其作用机制。方法婴幼儿喘息性支气管炎60例,随机分为2组,各30例,A组用阿奇霉素治疗,B组用地塞米松治疗,分别观察3d后的临床疗效;2组均测定其外周血清IL-4,IFN-γ浓度变化,并与15例健康婴幼儿(对照组)血清IL-4,IFN-γ浓度对比。结果A组与B组临床总有效率差异无统计学意义;整个喘息性支气管炎组与正常对照组相比IFN-γ和IL-4值差异均有统计学意义,IFN-γ下降,IL-4升高;各组治疗前与治疗后相比差异均有统计学意义,A组治疗后血清IFN-γ浓度增高、IL-4浓度下降;B组治疗后血清IFN-γ浓度下降、IL-4浓度也下降,且2组IFN-γ/IL-4值均显著升高。结论阿奇霉素治疗婴幼儿喘息性支气管炎有较好的疗效,能与地塞米松有同样的调节TH1及TH2细胞因子使之趋于平衡,并且有更好的促进细胞免疫作用。 相似文献
73.
蟾酥注射液对小鼠S180和人结肠癌HT-29裸鼠移植性肿瘤的影响 总被引:6,自引:0,他引:6
目的研究蟾酥注射液对小鼠移植性肿瘤 S180和人结肠癌 HT-29裸鼠移植性肿瘤的抑制作用.方法分别用小鼠 S180和人结肠癌 HT-29裸鼠两种荷瘤小鼠模型,观察药物对上述肿瘤的抑瘤作用,并镜下观察后者细胞凋亡情况.结果与荷瘤阴性对照组比较,蟾酥注射液各剂量组对小鼠 S180抑瘤率( IR)为 19.1%~38.2%(P<0.05),呈量效关系;而对人结肠癌 HT-29裸鼠移植性肿瘤的 IR为 9.5%~15.8%(P>0.05),也呈量效关系,但差异均未见统计学意义;环磷酰胺则能显著抑制小鼠 S180和 HT-29细胞裸鼠移植性肿瘤的生长( IR分别为70.7%和 67.1%, P<0.01),镜检可见其有显著促进肿瘤细胞凋亡作用;未发现实验药物出现明显的毒副作用.结论该实验所用的蟾酥注射液,对小鼠 S180有抑制作用,而对人结肠癌 HT-29裸鼠移植性肿瘤,则作用不明显,表明不同类型的肿瘤对其敏感性不同. 相似文献
74.
Ramirez Claudia C. MD Ma Fangchao MD PhD Federman Daniel G. MD † Kirsner Robert S. MD PhD ‡§ 《Dermatologic surgery》2005,31(7):748-753
Background Results from in vitro and animal studies suggest that cyclooxygenase (COX) inhibitors may reduce the risk of melanoma, but among humans, the evidence remains limited.
Objective In a pilot retrospective cohort, to determine the relationship between the use of COX inhibitors and the incidence, recurrence, and metastases of melanoma in high-risk patients.
Methods Reviewing computerized records at the Miami Veterans Affairs Medical Center, we retrospectively examined the association between COX inhibitor use and melanoma incidence, recurrence, and metastases in high-risk subjects: white subjects previously diagnosed with melanoma (1996–2003). We evaluated three potential outcomes: new melanoma diagnosis, recurrence of a previous melanoma, and melanoma metastasis.
Results Eighty-three subjects with melanoma were included. There was one metastasis among 28 subjects prescribed COX inhibitors, whereas four new melanomas (7.3%), two melanoma recurrences, and six metastases (10.9%) occurred among 55 patients not prescribed COX inhibitors. Although no individual outcomes measures reached statistical significance, combining the three measures, these were significantly lower in users of COX inhibitors compared with nonusers (1 vs 12; p = .05 ). After adjustment for age and tumor depth of invasion, COX inhibitor users had significantly lower rates of melanoma outcome measures (odds ratio 0.08; 95% confidence interval 0.01–0.77; p = .03 ).
Conclusion Potential exists for chemoprevention of melanoma among high-risk patients. 相似文献
Objective In a pilot retrospective cohort, to determine the relationship between the use of COX inhibitors and the incidence, recurrence, and metastases of melanoma in high-risk patients.
Methods Reviewing computerized records at the Miami Veterans Affairs Medical Center, we retrospectively examined the association between COX inhibitor use and melanoma incidence, recurrence, and metastases in high-risk subjects: white subjects previously diagnosed with melanoma (1996–2003). We evaluated three potential outcomes: new melanoma diagnosis, recurrence of a previous melanoma, and melanoma metastasis.
Results Eighty-three subjects with melanoma were included. There was one metastasis among 28 subjects prescribed COX inhibitors, whereas four new melanomas (7.3%), two melanoma recurrences, and six metastases (10.9%) occurred among 55 patients not prescribed COX inhibitors. Although no individual outcomes measures reached statistical significance, combining the three measures, these were significantly lower in users of COX inhibitors compared with nonusers (1 vs 12; p = .05 ). After adjustment for age and tumor depth of invasion, COX inhibitor users had significantly lower rates of melanoma outcome measures (odds ratio 0.08; 95% confidence interval 0.01–0.77; p = .03 ).
Conclusion Potential exists for chemoprevention of melanoma among high-risk patients. 相似文献
75.
无症状性炎性前列腺炎对血清PSA、fPSA的影响 总被引:3,自引:0,他引:3
目的 探讨无症状性炎性前列腺炎(NIH分类Ⅳ型)对血清PSA、fPSA的影响。方法 对比分析36例NIH分类Ⅳ型、42 例有症状性慢性前列腺炎(NIH分类ⅢA型)患者以及22例健康对照组的血清PSA、fPSA、fPSA/tPSA之间的差异。结果 血 清PSA、fPSA、fPSA/tPSA在Ⅳ型和ⅢA型前列腺炎患者间差异无显著性(P>0.05),但与正常对照组比较差异有显著性(P< 0.01)。结论 NIH分类Ⅳ型前列腺炎可引起血清PSA、fPSA升高。对无症状、高血清PSA患者行前列腺活检前,应考虑到患 Ⅳ型前列腺炎的可能。 相似文献
76.
Z. Peng Q. Liu Q. Wang E. Rector Y. Ma R. Warrington 《Clinical and experimental allergy》2007,37(7):1040-1048
BACKGROUND: Immunotherapy with anti-IgE antibodies for treatment of allergy is promising but a short half-life and extremely high cost limit its application. OBJECTIVE: We sought to develop IgE vaccines that induce longer-lasting auto-antibodies to neutralize self-IgE as an alternative therapy. METHODS: The vaccine was made by conjugating three synthetic peptides corresponding to human IgE receptor-binding sites to a carrier, hepatitis B surface antigen. To test the immunogenicity of the vaccine, rats were immunized with the vaccine or hepatitis B surface antigen as control. Serum IgG titres to human IgE and the IgE of other species were measured. The inhibition by rat antisera of the binding of human IgE to its receptor was assessed by ELISA, flow cytometry analysis, and passive cutaneous anaphylaxis (PCA), and its ability to recognize receptor-bound IgE was examined. The in vivo effect of the vaccine was evaluated in trichosanthin-sensitized mice and rats. In the preventative study, vaccination started before sensitization commenced, while in the treatment study, vaccination started after sensitization. Sensitized mice and rats receiving injections of the carrier served as controls. Trichosanthin-specific IgE was measured using PCA. RESULTS: Sera from vaccine-immunized rats contained high titre antibodies that reacted with soluble and plate-bound but not with receptor-bound human IgE; they also reacted with mouse, rat, and dog IgE. Furthermore, the sera inhibited the binding of human IgE to its receptor in a dose-dependent manner. In preventative and treatment studies, serum trichosanthin-specific IgE levels were significantly reduced in vaccinated groups compared with controls. CONCLUSION: Antibodies against self-IgE can be induced by IgE peptide-based vaccines, which are effective in preventing the increase of IgE and in down-regulating IgE in sensitized animals. 相似文献
77.
78.
Using a two‐stage global scan design, we analyzed general population replicates 1 and 42 of the Genetic Analysis Workshop (GAW) 12 simulated data set using three methods: revisited Haseman‐Elston (HER), maximum likelihood variance estimation (ML), and variance components (VC). Three marker densities, 5‐, 10‐, and 15‐cM intervals, were examined in the first‐stage scan. We found that the 10‐cM interval appears to be the most cost‐effective approach in genotyping without sacrificing power when using a first stage significance level of 0.01. Subsequently, we performed the second‐stage scan at 1‐cM intervals for those putative positive regions identified in the first‐stage scan at a significance level of 0.01. We also compared the power to detect linkage using different numbers of sib pairs for a genome‐wide scan at a 10‐cM interval and found that power decreases nonlinearly as the number of sib pairs decreases. © 2001 Wiley‐Liss, Inc. 相似文献
79.
80.
本文分析91例60岁以上急性心肌梗塞(AMI)病人的心电图 V_1导联上 P 波的终末电势(PTFv_1)由 V_1导联的负向 P 波深度×宽度求得,单位为 mm·s。正常值≥-0.03mm·s,本组 PTFv_1异常者共44例,占48.4%,与 AMI 病人的年龄、梗塞部位、面积扩大及泵衰竭的增重有很大关系。经过治疗,随着病情的好转 PTFv_1可恢复正常。因此,PTFv_1对老年 AMI 的预后判断具有很大的意义。 相似文献