首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   1252篇
  免费   71篇
  国内免费   1篇
耳鼻咽喉   2篇
儿科学   56篇
妇产科学   16篇
基础医学   115篇
口腔科学   14篇
临床医学   116篇
内科学   267篇
皮肤病学   11篇
神经病学   69篇
特种医学   18篇
外国民族医学   1篇
外科学   128篇
综合类   29篇
预防医学   158篇
眼科学   93篇
药学   100篇
中国医学   4篇
肿瘤学   127篇
  2023年   11篇
  2022年   21篇
  2021年   48篇
  2020年   27篇
  2019年   30篇
  2018年   47篇
  2017年   30篇
  2016年   40篇
  2015年   47篇
  2014年   71篇
  2013年   66篇
  2012年   91篇
  2011年   110篇
  2010年   63篇
  2009年   45篇
  2008年   60篇
  2007年   56篇
  2006年   61篇
  2005年   52篇
  2004年   59篇
  2003年   48篇
  2002年   41篇
  2001年   21篇
  2000年   27篇
  1999年   18篇
  1998年   3篇
  1997年   4篇
  1996年   3篇
  1995年   7篇
  1994年   2篇
  1993年   5篇
  1992年   9篇
  1991年   7篇
  1990年   11篇
  1989年   14篇
  1988年   5篇
  1987年   4篇
  1986年   9篇
  1985年   11篇
  1984年   7篇
  1983年   3篇
  1981年   2篇
  1980年   2篇
  1979年   2篇
  1978年   4篇
  1977年   4篇
  1974年   2篇
  1973年   2篇
  1970年   2篇
  1966年   2篇
排序方式: 共有1324条查询结果,搜索用时 15 毫秒
1.
Angiosarcoma is a rare, highly malignant tumor arising from endothelial cells of small blood vessels. They usually occur in the skin, deep soft tissues, breast and liver. Pleural angiosarcomas are extremely rare and are restricted to case reports in medical literature. It is very difficult to distinguish them from malignant mesotheliomas on clinical, radiological and even histopathological features. Immunohistochemistry is valuable in making the diagnosis, showing negative reactivity for mesothelial markers and positivity for vascular markers. Prognosis is generally dismal except in occasional cases where the disease is localized and amenable for surgical resection. We report a 55-year-old man who presented to us with chest pain, cough and hemoptysis and was diagnosed to have a pleural angiosarcoma.  相似文献   
2.
OBJECTIVE: The aim of this study was to assess the quality of life and psychologic profile during radiation therapy for head and neck cancer. STUDY DESIGN AND SETTING: The University of Washington QoL instrument and the Hospital Anxiety and Depression Scale were administered to 202 patients at two or three time points during radiation therapy. RESULTS: A total of 118 (54.6%) patients completed the questionnaires at the beginning and at the end of the study. A mid-treatment dataset was also available for 67 (31.0%) patients. There was a statistically significant deterioration in composite QoL scores (P < 0.000) and a statistically significant increase in depression (P < 0.000). There was no difference in anxiety levels (P = 0.276). CONCLUSION: Patients undergoing radiation are increasingly depressed as treatment progresses, with worsening QoL during the treatment. SIGNIFICANCE: This study underlines the need for good psychologic support during radiation therapy in head and neck cancer.  相似文献   
3.
Misra LN  Shawl AS  Raina VK 《Planta medica》1988,54(2):165-166
The essential oil of DRACOCEPHALUM NUTANS L. (Lamiaceae) has been investigated for the first time. The GC-MS analysis of the oil showed the presence of about 25 monoterpenoids including pinocamphone (56.4%), beta-pinene (12.7%), isopinocamphone (4.3%), alpha-phellandrene (4.6%), and isopinocampheol (3.7%).  相似文献   
4.
Results of primary surgery with or without locoregional radiotherapy (LRRT) are poor in stage III (T4b, NO-2, M0) breast cancer. Combination of mitoxantrone, mitomycin-c and methotrexate (MMM) has been reported to be as efficacious as doxorubicin based protocols with advantages of reduced nausea, vomiting, alopecia and cardiotoxicity. We tested MMM chemotherapy with LRRT and surgery in locally advanced breast cancer (LABC) with a view to assess response, survival, breast conservation, cost and toxicity. Fifty two previously untreated patients were given Mitoxantrone: 8 mg/m sq by infusion on days 1 and 21, Mitomycin-C: 8 mg/m sq by infusion on day 1 and Methotrexate: 35 mg/m sq i.v. on days 1 and 21. Cycles were repeated every 42 days. After 3 cycles LRRT was given if lump reduced to less than 2 cms. Otherwise patients were subjected to modified radical mastectomy (MRM) or radical mastectomy (RM). Following this 3 more cycles of chemotherapy were given. Patients with soft tissue, skin or heavy nodal involvement also received LRRT. Tamoxifen 20 mg daily was prescribed at the end of chemotherapy to postmenopausal patients. Complete/partial responses were seen in 5 and 26 patients, respectively after chemotherapy giving an overall response of 59.5%. Twenty four patients each had LRRT and MRM/RM. Responses could be significantly enhanced by LRRT/and or surgery. Nineteen out of 25 relapses were at distant sites. Breast conservation was achieved in 24/52 (46%) patients. Three year disease free and overall survival was 54% and 65%, respectively. There was 1 toxic death. Severe prolonged myelosuppresion was seen in those who also received LRRT. Mucositis, alopecia, nausea and vomiting were minor problems. Overall, combination was less expensive than doxorubicin based protocols.  相似文献   
5.
Amphiphysin is a protein peripherally associated with synapticvesicles. It is expressed in many neurons, certain endocrinecell types, and spermatocytes. Autoantibodies against amphiphysinoccur in patients afflicted with a rare neurologic autoimmunedisease, paraneoplastic Stiff—Man syndrome. To providea basis for the understanding of antl-amphiphysin autolmmunity,we have cloned cDNAs and determined the primary structure ofhuman amphiphysin. Comparison with chicken amphiphysin definesdomains of low and high amino acid sequence conservation. Asa candidate for heritable disorders of the nervous system, endocrinetissues or male fertility, the human amphiphysin gene was mappedto chromosome 7, region p13–p14.  相似文献   
6.
Airway mucus hypersecretion is a prominent feature of many obstructive lung diseases. We thus determined the ontogeny and exocytic phenotype of mouse airway mucous cells. In naive mice, ciliated (approximately 40%) and nonciliated (approximately 60%) epithelial cells line the airways, and > 95% of the nonciliated cells are Clara cells that contain Clara cell secretory protein (CCSP). Mucous cells comprise < 5% of the nonciliated cells. After sensitization and a single aerosol antigen challenge, alcian blue-periodic acid Schiff's positive mucous cell numbers increase dramatically, appearing 6 h after challenge (21% of nonciliated/nonbasal cells), peaking from Days 1-7 (99%), and persisting at Day 28 (65%). Throughout the induction and resolution of mucous metaplasia, ciliated and Clara cell numbers identified immunohistochemically change only slightly. Intracellular mucin content peaks at Day 7, and mucin expression is limited specifically to a Clara cell subset in airway generations 2-4 that continue to express CCSP. Functionally, Clara cells are secretory cells that express the regulated exocytic marker Rab3D and, in antigen-challenged mice, rapidly secrete mucin in response to inhaled ATP in a dose-dependent manner. Thus, Clara cells show great plasticity in structure and secretory products, yet have molecular and functional continuity in their identity as specialized apical secretory cells.  相似文献   
7.
The case is reported of a 37-year-old woman who complained of a gradually progressive mass in the left medial canthus area of one year's duration associated with epiphora. Although the clinical and investigative observations were suggestive of an acquired lacrimal sac cyst, the diagnosis was clinched by the operative and histopathological findings. Excision of the cyst along with dacryocystorhinostomy provided complete cure for this patient.  相似文献   
8.
BACKGROUND AND OBJECTIVES: To note the effect on filtration function of using polyglactin sutures for scleral flap suturing in trabeculectomy. PATIENTS AND METHODS: Polyglactin sutures were compared with nylon sutures to secure the scleral flap of trabeculectomy in 30 consecutive eyes. Parameters studied were intraocular pressure, central anterior chamber depth, and bleb score in this randomized prospective study. RESULTS: Observations regarding intraocular pressure, central anterior chamber depth and bleb score in the early postoperative period were comparable in the 2 groups. The results at 12 months follow-up reveal a lower mean IOP (P < 0.05) and a higher mean bleb score (P < 0.05) in the group with polyglactin sutures. Success rate (defined as IOP < 21 mm Hg) at 12 months was 100% with use of polyglactin sutures compared to 80% with nylon sutures. CONCLUSIONS: Polyglactin sutures can be used as an alternative to nylon sutures for scleral flap suturing in trabeculectomy, with the possible additional benefit of better long-term filtration function.  相似文献   
9.
Traumatic injuries to the rectum although uncommon can result in virulent complications and even death. Diverting colostomy, presacral drainage, distal wash out and rectal repair, when feasible, have become the standard treatment for rectal injuries. We report an unusual case of rectal injury resulting in anorectal avulsion from skin and surrounding tissues.  相似文献   
10.
Herein, zinc oxide nanoparticles (ZnO NPs) were greenly synthesized from Tridax procumbens aqueous leaf extract (TPE) and characterized physically (e.g., Fourier-transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM)) and biologically (test of their anti-diabetic activity). Anti-diabetic activities of TPE and TPE-derived ZnO NPs have been carried out in a streptozotocin (STZ)—induced diabetic rat model. Diabetes mellitus (DM) was induced with a single intraperitoneal dosage of the glucose analogue STZ (55 mg/Kg) known to be particularly toxic to pancreatic insulin-producing beta-cells. TPE and TPE-derived ZnO NPs were administered orally, once every day for 21 days in diabetic rats, at 100 and 200 mg/Kg, respectively. The standard antidiabetic medication, glibenclamide, was used as a control at a dose of 10 mg/Kg. Various parameters were investigated, including bodyweight (bw) variations, glycemia, lipidaemia, glycated hemoglobin (HbA1c), and histopathological alterations in the rat’s liver and pancreas. The TPE-mediated NPs were small, spherical, stable, and uniform. Compared to TPE and, to a lesser extent, glibenclamide, TPE-derived ZnO NPs lowered blood glucose levels considerably (p < 0.05) and in a dose-dependent manner while preventing body weight loss. Further, positive benefits for both the lipid profile and glycated hemoglobin were also noticed with TPE-derived ZnO NPs. The histopathological assessment revealed that synthesized TPE-derived ZnO NPs are safe, non-toxic, and biocompatible. At 200 mg/Kg/day, TPE-derived ZnO NPs had a more substantial hypoglycemic response than at 100 mg/Kg/day. Thus, in this first reported experimental setting, ZnO NPs biosynthesized from the leaf extract of Tridax procumbens exert more potent anti-diabetic activity than TPE and glibenclamide. We conclude that such a greenly prepared nanomaterial may be a promising alternative or complementary (adjuvant) therapy, at least to the current Indian’s traditional medicine system. Translational findings are prompted in human populations to determine the efficacy of these NPs.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号