全文获取类型
收费全文 | 4632篇 |
免费 | 269篇 |
国内免费 | 20篇 |
专业分类
耳鼻咽喉 | 36篇 |
儿科学 | 128篇 |
妇产科学 | 83篇 |
基础医学 | 691篇 |
口腔科学 | 148篇 |
临床医学 | 357篇 |
内科学 | 1158篇 |
皮肤病学 | 110篇 |
神经病学 | 380篇 |
特种医学 | 67篇 |
外科学 | 516篇 |
综合类 | 30篇 |
一般理论 | 1篇 |
预防医学 | 162篇 |
眼科学 | 207篇 |
药学 | 427篇 |
中国医学 | 35篇 |
肿瘤学 | 385篇 |
出版年
2023年 | 44篇 |
2022年 | 58篇 |
2021年 | 115篇 |
2020年 | 49篇 |
2019年 | 86篇 |
2018年 | 105篇 |
2017年 | 78篇 |
2016年 | 108篇 |
2015年 | 100篇 |
2014年 | 121篇 |
2013年 | 167篇 |
2012年 | 251篇 |
2011年 | 312篇 |
2010年 | 174篇 |
2009年 | 158篇 |
2008年 | 294篇 |
2007年 | 314篇 |
2006年 | 282篇 |
2005年 | 307篇 |
2004年 | 289篇 |
2003年 | 264篇 |
2002年 | 283篇 |
2001年 | 84篇 |
2000年 | 88篇 |
1999年 | 73篇 |
1998年 | 52篇 |
1997年 | 38篇 |
1996年 | 41篇 |
1995年 | 28篇 |
1994年 | 30篇 |
1993年 | 18篇 |
1992年 | 47篇 |
1991年 | 42篇 |
1990年 | 47篇 |
1989年 | 35篇 |
1988年 | 23篇 |
1987年 | 23篇 |
1986年 | 25篇 |
1985年 | 31篇 |
1984年 | 31篇 |
1983年 | 15篇 |
1982年 | 12篇 |
1981年 | 14篇 |
1980年 | 18篇 |
1979年 | 23篇 |
1978年 | 18篇 |
1974年 | 16篇 |
1972年 | 12篇 |
1971年 | 11篇 |
1970年 | 11篇 |
排序方式: 共有4921条查询结果,搜索用时 31 毫秒
11.
Mikio Mikami Chisei Tei Kyoko Takehara Shinichi Komiyama Atsushi Suzuki Takanori Hirose 《International journal of gynecological pathology》2003,22(2):205-208
A 38-year-old female presented with a lower abdominal mass. During the operation the mass was found to be retroperitoneal and was excised. Gross examination revealed a mucin-containing cystic lesion with a mural nodule. On microscopic examination, the cystic areas were lined by an invasive mucinous adenocarcinoma and the nodule was composed of an anaplastic sarcomatoid tumor that was immunoreactive for cytokeratin. This present case is the 21st example of a retroperitoneal primary mucinous cystadenocarcinoma and the fourth with a mural nodule. Three of four cases with a mural nodule, including our case, had a rapidly fatal outcome. 相似文献
12.
Accumulation and declination of chlordane congeners in mice 总被引:1,自引:0,他引:1
A metabolic experiment involving technical chlordane in mice was carried out in vivo by single and repeated oral administration. In the single oral dose group, residues of trans- and cis-chlordane in mouse whole body showed a maximum content at 5 hours after administration; thereafter, the body content decreased rapidly. For other congeners, the residues of trans- and cis-nonachlor reached a maximum at 10 hours, the residual levels forming a plateau. The intermediate metabolite oxychlordane was detected 1 hour after the administration of technical chlordane, the content in the mouse body increasing with time. In the repeated oral dose group, although technical chlordane was administered repeatedly, increases in trans- and cis-chlordane content were not observed for 29 days. On the other hand, the nonachlor and oxychlordane content increased gradually throughout the observation period. These findings suggest that the accumulation of nonachlors and oxychlordane in the animal body must be high and sufficient attention must be paid to their toxic effect. 相似文献
13.
Patients on long-term hemodialysis (HD) are known to develop amyloid osteoarthropathy, evidenced as cystic radiolucencies on X-rays of the affected joints. To study the relationship between cystic radiolucencies and amyloid osteoarthropathy in 394 patients, we classified the severity of the cystic radiolucencies seen in the wrist joint on a 4-point scale and evaluated the association between lesion severity (grade) and several parameters. Biopsy was performed in 8 patients with 11 bone cysts of the wrist joint who had been operated for carpal tunnel syndrome. HD for 10 years or longer, age 50 or older and the presence of carpal tunnel syndrome were associated with severe cyst rating. There was no association between lesion grade and serum level of PTH-C, aluminum or beta 2-microglobulin (B2M). Ten of the 11 biopsied bone cysts in 8 patients with carpal tunnel syndrome demonstrated amyloid deposits which reacted with B2M. We conclude that a cystic radiolucency observed in the wrist joint of a patient undergoing HD indicates the deposition of amyloid. The cyst grade provides a useful marker for the severity of amyloid osteoarthropathy in HD patients. 相似文献
14.
15.
The present study was undertaken to elucidate the effect on platelet aggregation of the prothrombin-converting reaction on platelets with or without activated protein C (APC). A reaction mixture of washed platelets from human individuals, Factor Xa and prothrombin markedly induced platelet aggregation; maximum aggregation rates, 31.3–92.5%, and times to reach to maximum aggregation, 11.6 to 20.1 min. This aggregation was inhibited by the addition of APC with 50% inhibition concentration (IC50) value of 14.4 U/ml. APC also inhibited thrombin generation in the reaction mixture in a dose-dependent manner with IC50 value of 0.96 U/ml. However, APC did not inhibit the thrombin (0.1 CU/ml)-induced platelet aggregation at concentrations of up to 30 U/ml. These findings suggest that APC has no direct inhibitory effect on platelet aggregation and that APC inhibits platelet aggregation through inhibition of thrombin generation. 相似文献
16.
A new Le Fort I internal distraction device in the treatment of severe maxillary hypoplasia. 总被引:2,自引:0,他引:2
Jaime Gateno Eric R Engel John F Teichgraeber Kyoko E Yamaji James J Xia 《Journal of oral and maxillofacial surgery》2005,63(1):148-154
PURPOSE: The purpose of this pilot study was to test a new Le Fort I internal distraction device. PATIENTS AND METHODS: A new internal Le Fort I distraction device designed by 1 of the authors was used in 3 patients with cleft lip and palate and severe maxillary hypoplasia who needed maxillary advancements in excess of 12 mm. Presurgical planning used CASSOS (SoftEnable Technology, Ltd, Hong Kong SAR, China) prediction tracing software and a stereolithographic model to calculate the distraction vector. The distractors were pre-bent and installed on the stereolithographic model and activated to advance the maxilla. Surgery was performed in a conventional manner, and distraction was started after a 7-day latency phase at the rate of 1 mm/day and continued until the presurgical plan was achieved. The distractor was removed after a 3-month consolidation phase. Cephalometric radiographs were taken at the completion of each phase. RESULTS: This new Le Fort I internal distraction device successfully distracted the maxillae as planned in all 3 patients. At the end of the distraction phase, the maxillary advancement was measured at 15.8 mm, 15.8 mm, and 13.5 mm, respectively. In each patient, a clockwise rotation of the maxilla was observed with a tendency to a posterior open bite. Postoperative radiographs also showed that the actual distraction vectors differed from the planned vectors. After the consolidation phase, radiographs showed a relapse of 2.6 mm, 0 mm, and 5.0 mm, respectively. There was no further relapse on 3-month follow-up radiographs. Each case showed radiographic evidence of excellent new bone formation at the osteotomy sites. CONCLUSION: The new Le Fort I internal distraction device produced the necessary advancement in all 3 patients. The study also showed that the actual distraction vector differed from the planned vector. This discrepancy was caused by a clockwise rotation of the maxilla during the distraction. Finally, the study showed a variable relapse rate not previously reported in maxillary distraction. 相似文献
17.
Kenji Takahashi Toshikazu Kubo Kappei Kobayashi Jiro Imanishi Masaharu Tkigawa Yuji Arai Yasusuke Hirasawa 《Journal of orthopaedic research》1997,15(1):150-158
The present study investigated the influence of hydrostatic prssure on the exprssion of cytokines and heat shock protein 70 in a chondrocyte-like cell line. Chondrocyte-like cells (HCS-2/8) were exposed to hydrostatic pressur by a special pressure apparatus. Total RNA for cytokines (interleukin-1β, basic fibroblast growth factor, insulin-like growth factor-I, and transforming growth factor-β1) and for heat shock protein 70 was extracted and was analyzed by a polymerase chain reaction method and Northern blotting. An assay for incorporation of [35S]sulfate was performed to assess proteoglycan synthesis. The expression of transforming growth factor-β1 mRNA was enhanced after exposure to 5 Mpa of hydrostatic prssure and was reduced after 50 Mpa, whereas the expression of heat shock protein 70 was enhanced following exposure to 50 Mpa of hydrostatic pressure. The incorporation of [35S]sulfate into the cultured cells increased following exposure to 1-5 Mpa of hydrostatic pressure and decreased following 10-50 Mpa of pressure. These results suggest that hydrostatic pressure at physiologic levels enhances the expression of transforkming growth factor-β mRNA in addition to increasing proteoglycan synthesis in chondrocytes and that excessively high hydrostatic pressure reduces the expression of transforming growth factor-β1 mRNA and increases the expression of heat shock protein 79 mRNA while decreasing proteoglycan synthesis. 相似文献
18.
In basilar artery thrombosis, hemiparesis without obvious brainstem signs may precede the tetraplegia with coma or a locked-in state. This premonitory hemiparesis was called as "herald hemiparesis" by Fisher (1988). Its early detection is important because immediate anticoagulant therapy may prevent its evolution. We reported two patients with such hemiparesis. The first case was a 71-year-old diabetic and hypertensive man who was admitted because of right hemiparesis, dysarthria and decreased spontaneous speech. Initially, his symptoms looked like those of a left cerebral lesion. CT scans revealed no fresh cerebrovascular lesion. A few hours later, a myoclonic movement appeared in his left lower limb, and right MLF syndrome developed. We thought he had basilar artery thrombosis and we started intravenous administration of heparin. But he developed tetraplegia with locked-in state. The second case was a 76-year-old diabetic and hypertensive man with a confusional state, right hemiparesis, dysarthria and conjugate gaze deviation to left. After admission, he rapidly became comatose and developed respiratory arrest. CT scans revealed low density areas in the brainstem, cerebellum and the occipital lobe. He died ten days later. Early detection of herald hemiparesis is by no means easy. However, severe dysarthria and myoclonic jerks in a patient with hemiparesis should be considered as warning signs to indicate the herald hemiparesis with subsequent severe brainstem infarction. 相似文献
19.
Previous studies have suggested that facial displays in the presence of others are influenced by the relationship with accompanying persons. In these studies, subjects participated with friends or strangers, without any focus on social interactions between partners. In the current study, pairs of friends or strangers viewed film clips expected to elicit positive and negative affects; the control group participated without partners. We measured synchronous smiles between partners as a social interactive display, in addition to the duration and the frequency of smiles and frowns. Subjective emotion and social motive were also measured. Smiles were facilitated by the presence of a friend than a stranger or the condition of lone participation, regardless of stimulus valence. Synchronous smiles and the communication motive were also enhanced with a friend than with a stranger. These results suggested that the expression of smiles was facilitated by the communication motive and social interactions between partners. 相似文献
20.
Tomimori Y Muto T Fukami H Saito K Horikawa C Tsuruoka N Saito M Sugiura N Yamashiro K Sumida M Kakutani S Fukuda Y 《Laboratory investigation; a journal of technical methods and pathology》2002,82(6):789-794
An epicutaneous application of 2,4-dinitrofluorobenzene (DNFB) to a mouse ear caused a transient skin swelling, and the repetition of the challenge enlarged the contact dermatitis. The repeated challenge with DNFB also induced eosinophil infiltration on the application site. Administration of a chymase inhibitor significantly inhibited the ear swelling as well as eosinophil accumulation. An intradermal injection of human chymase to the mouse ear also elicited transient skin swelling and eosinophil infiltration, both of which were augmented in proportion to the number of injections. Human serum albumin and heat-inactivated chymase failed to induce such skin reactions, suggesting the participation of proteolytic activity of the enzyme. In addition, chymase stimulated eosinophil migration in vitro in a concentration-dependent manner. Taken together, these observations suggest that mast cell chymase may contribute to development of the DNFB-induced dermatitis, probably by promoting eosinophil infiltration. It is therefore possible that chymase plays a role in pathogenesis of chronic dermatitis such as atopic dermatitis. 相似文献