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   521篇
  免费   23篇
儿科学   20篇
妇产科学   137篇
基础医学   56篇
口腔科学   4篇
临床医学   28篇
内科学   134篇
神经病学   22篇
特种医学   12篇
外科学   81篇
综合类   2篇
预防医学   18篇
药学   8篇
肿瘤学   22篇
  2022年   3篇
  2021年   5篇
  2020年   5篇
  2019年   5篇
  2018年   9篇
  2016年   8篇
  2015年   9篇
  2014年   9篇
  2013年   13篇
  2012年   15篇
  2011年   18篇
  2010年   20篇
  2009年   17篇
  2008年   20篇
  2007年   33篇
  2006年   40篇
  2005年   39篇
  2004年   23篇
  2003年   30篇
  2002年   12篇
  2001年   16篇
  2000年   8篇
  1999年   13篇
  1998年   3篇
  1997年   6篇
  1996年   4篇
  1993年   8篇
  1992年   13篇
  1991年   13篇
  1990年   14篇
  1989年   11篇
  1988年   8篇
  1987年   9篇
  1986年   13篇
  1985年   11篇
  1984年   12篇
  1983年   6篇
  1982年   3篇
  1981年   3篇
  1980年   2篇
  1979年   6篇
  1977年   2篇
  1974年   1篇
  1973年   3篇
  1972年   1篇
  1971年   1篇
  1970年   6篇
  1969年   5篇
  1968年   2篇
  1967年   1篇
排序方式: 共有544条查询结果,搜索用时 15 毫秒
101.
BACKGROUND: During IVF or ICSI cycles, ovarian hyperstimulation syndrome (OHSS) is a major problem. The aim of this prospective, multicentre, comparative study (using historical controls) was to assess the efficacy of a GnRH antagonist protocol in preventing OHSS in selected patients who had experienced OHSS or had been at risk of OHSS in their previous IVF/ICSI attempt. METHODS AND RESULTS: Patients underwent a new cycle where the same gonadotrophin protocol was used [same dose of recombinant FSH (rFSH)] but a different protocol was used for pituitary desensitization: cetrorelix 0.25 mg multiple-dose antagonist instead of GnRH agonist long protocol. Cetrorelix 0.25 mg was administered daily, starting when the leading follicle reached a diameter of 14 mm. In other words, rFSH was administered in the new cycle according to the dosage and the step-up or step-down modalities used during the previous cycle, independently of ultrasound findings and serum estradiol (E(2)) levels. Eighty-seven patients entered the study. Out of the 87 cycles involving GnRH agonists, 49 (56.3%) were cancelled and out of the 87 involving GnRH antagonists 28 (32.2%) were cancelled [McNemar's test; 95% confidence interval (CI) -35.8% to -11.2%; P < 0.001]. After GnRH agonist cycles, we recorded 24 cases of OHSS (18 moderate and six severe; 27.6%), whereas after the GnRH antagonist cycles there were 10 cases of OHSS (nine moderate and one severe; 11.5%) (95% CI-26.4% to -5.7%; P = 0.006). There was a statistically significant reduction in the total number of follicles with a diameter >10 mm (Wilcoxon's test; Z = 6.1; P < 0.001) and of E(2) levels on the day of HCG administration (2538 versus 4322.4 pg/ml; P < 0.001) in the GnRH antagonist cycles versus GnRH agonist cycles. Twenty-nine patients had an embryo transfer in the first cycle (76.3% of oocyte retrievals) and 57 in the cycle using GnRH antagonist (96.6%). This 20.3% difference was also significant (Z-test; 95% CI 6.8-36.0%; P = 0.003). After the antagonist cycles, 18 pregnancies (20.7 per initiated cycle; 31.6% per embryo transfer) were obtained. CONCLUSIONS: Although this study presents some limitations owing to the use of historical controls, our data show a favourable effect of GnRH antagonists in reducing the incidence of OHSS and the number of assisted fertilization cycles cancelled because of the risk of OHSS in high responder patients. As a consequence, GnRH antagonist plus gonadotrophin administration could also increase the percentage of oocyte retrievals and embryo transfers in this high risk group of patients.  相似文献   
102.
BACKGROUND:A specific and still poorly investigated issue in the field of infertility is represented by the impact that the need for IVF techniques may have on health-related quality of life (HRQoL). METHODS: A total of 1000 consecutive couples (1000 women and 1000 men) were invited to complete the Health Survey Short Form (SF-36) questionnaire separately, prior to initiating their first IVF attempt in our unit. Patients were also invited to report about demographic and clinical characteristics. RESULTS: A total of 1936 (96.8%) agreed to participate. Male SF-36 scores were higher than those reported by women. Duration of infertility and previous IVF attempts significantly influenced HRQoL (P < 0.01). When scores were plotted in relation to the normative source of the Italian general population stratified by gender, corresponding age and geographical area, the subjective health profile did not significantly differ from the normative sample for both women and men. CONCLUSION: The need for IVF did not seem to markedly influence subjective health status. Conversely, duration of infertility and failure to achieve a pregnancy through IVF might have a negative impact.  相似文献   
103.
BACKGROUND: In 2004, a law regulating assisted reproduction techniques (ART) was passed in Italy. The new rules allow for the formation and transfer of a maximum of three embryos at one time, whereas embryo selection and embryo storage are prohibited. The aim of this study is to evaluate the impact of these restrictions on ICSI outcome in couples affected by severe male factor infertility. METHODS: Thirteen Italian ART Units were involved in this study. Data were collected on ICSI cycles performed during 2 years before (control group) and 2 years after (study group) the enforcement of the law. Only cases of obstructive azoospermia (OA), non-obstructive azoospermia (NOA) and severe oligoastenoteratozoospermia (OAT) (sperm count 相似文献   
104.
The tumor necrosis factor receptor-associated factor 1 (TRAF1) participates in the signal transduction of various members of the tumor necrosis factor receptor (TNFR) family, including TNFR2, CD40, CD30, and the Epstein-Barr virus (EBV)-encoded latent membrane protein 1 (LMP1). In vitro, TRAF1 is induced by LMP1, and previous studies have suggested that expression of TRAF1 is higher in EBV-associated tumors than in their EBV-negative counterparts. To determine whether this was the case in posttransplant lymphoproliferative disease (PTLD) and related disorders, we used immunohistochemistry to analyze expression of TRAF1 in a total of 42 such lesions arising in a variety of immunosuppressive states. The specimens consisted of 22 PTLD lesions, 18 acquired immunodeficiency syndrome-associated lymphomas, including 6 primary central nervous system lymphomas, and 2 cases of Hodgkin disease. The presence of latent EBV infection was determined by EBER in situ hybridization, and expression of EBV-LMP1 was detected by immunohistochemistry. Latent EBV infection, as determined by a positive EBER signal, was detected in 36 of 42 tumors. Of the EBER-positive specimens, 30 of 36 also expressed LMP1. Twenty-four of 30 LMP1-positive tumors, including both Hodgkin disease specimens, expressed TRAF1, compared with only 3 of 12 LMP1-negative tumors. This difference was statistically significant (P <.005). These results show frequent expression of TRAF1 at the protein level in LMP1-positive PTLD and related disorders and suggest an important role for LMP1-mediated TRAF1 signaling in the pathogenesis of EBV-positive tumors arising in immunosuppressive states.  相似文献   
105.
Fifty-seven patients who had progressed during or relapsed after randomized first-line combination chemotherapy containing cisplatin or carboplatin were entered into a crossover study in which the analog not previously assigned was administered alone as salvage treatment. Carboplatin and cisplatin were administered at doses of 400 and 100 mg/m2, respectively, every 28 days. Among the 24 patients enrolled in the cisplatin arm, 6 (25%) objective responses (ORs) (3 complete, 3 partial) were observed, whereas 3 partial responses were obtained in the 33 carboplatin-treated patient (9%). Analysis of results, according to response to first-line chemotherapy, demonstrated that the patients who progressed were sensitive only to cisplatin second-line treatment (OR: 3/12), with no responders among carboplatin-treated patients (OR: 0/11). All patients were treated on an outpatient basis and therapy-related toxic effects were mild, consisting chiefly of myelosuppression, and more frequent in the carboplatin group. In our opinion, carboplatin 400 mg/m2 per cycle is scarcely effective in patients with refractory or relapsed ovarian cancer pretreated with cisplatin regimens, whereas cisplatin 100 mg/m2 per cycle appears to be an effective salvage therapy even in patients not responding to carboplatin. The dose of carboplatin should be further escalated especially in refractory patients.  相似文献   
106.
Ribociclib plus an aromatase inhibitor and ovarian function suppression is the preferred first-line option for pre-/perimenopausal women with hormone receptor-positive/human epidermal growth factor receptor-2-negative advanced or metastatic breast cancer. We opened an italian managed access program (MAP) that permitted access to ribociclib to selected patients and allowed to collect informative results on the clinical impact of the therapy. The MAP (April 2018–May 2020) included 64 premenopausal patients, with characteristics similar to those of the MONALEESA-7 trial. Of 57 patients with a known response, 48 (84.2%) achieved a clinical benefit (i.e., complete response, N = 7 (12.3%); partial response, N = 17 (29.8%); stable disease, N = 24 (42.1%)), while 9 (15.8%) experienced tumor progression. Some patients (N = 15–23.4%) needed ribociclib dose reduction because of adverse events. Thereafter, the treatment was well tolerated, and no new safety signals emerged. Our study is the first reported Italian real-world evidence of ribociclib effectiveness in premenopausal HR+/HER2− advanced breast cancer patients. Response and clinical benefit rates were particularly encouraging compared with those of the ribociclib group of MONALEESA-7. Our work confirms that ribociclib in combination with endocrine therapy is highly effective in the treatment of premenopausal HR+/HER2− advanced breast cancer patients with an expected safety profile.  相似文献   
107.
Polydopamine (PDA) is a synthetic eumelanin polymer mimicking the biopolymer secreted by mussels to attach to surfaces with a high binding strength. It exhibits unique adhesive properties and has recently attracted considerable interest as a multifunctional thin film coating. In this study, we demonstrate that a PDA coating on silica- and polymer-based materials improves the entrapment and retention of uremic toxins produced in specific diseases. The low-cost natural nanotextured fossil diatomaceous earth (DE), an abundant source of mesoporous silica, and polyvinylpyrrolidone-co-Styrene (PVP-co-S), a commercial absorbent comprising polymeric particles, were easily coated with a PDA layer by oxidative polymerization of dopamine at mild basic aqueous conditions. An in-depth chemical-physical investigation of both the resulting PDA-coated materials was performed by SEM, AFM, UV-visible, Raman spectroscopy and spectroscopic ellipsometry. Finally, the obtained hybrid systems were successfully tested for the removal of two uremic toxins (indoxyl sulfate and p-cresyl sulfate) directly from patients’ sera.  相似文献   
108.
109.
110.
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