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   4578篇
  免费   253篇
  国内免费   17篇
耳鼻咽喉   1篇
儿科学   72篇
妇产科学   979篇
基础医学   299篇
口腔科学   7篇
临床医学   159篇
内科学   386篇
皮肤病学   262篇
神经病学   51篇
特种医学   39篇
外科学   1906篇
综合类   121篇
预防医学   113篇
眼科学   5篇
药学   113篇
中国医学   54篇
肿瘤学   281篇
  2024年   10篇
  2023年   113篇
  2022年   179篇
  2021年   234篇
  2020年   281篇
  2019年   138篇
  2018年   178篇
  2017年   136篇
  2016年   163篇
  2015年   234篇
  2014年   373篇
  2013年   305篇
  2012年   322篇
  2011年   233篇
  2010年   226篇
  2009年   252篇
  2008年   189篇
  2007年   184篇
  2006年   152篇
  2005年   124篇
  2004年   92篇
  2003年   94篇
  2002年   79篇
  2001年   54篇
  2000年   50篇
  1999年   57篇
  1998年   49篇
  1997年   35篇
  1996年   50篇
  1995年   40篇
  1994年   19篇
  1993年   14篇
  1992年   18篇
  1991年   12篇
  1990年   19篇
  1989年   25篇
  1988年   16篇
  1987年   16篇
  1986年   10篇
  1985年   8篇
  1984年   8篇
  1983年   11篇
  1982年   8篇
  1981年   10篇
  1980年   7篇
  1979年   4篇
  1978年   4篇
  1977年   3篇
  1976年   3篇
  1972年   2篇
排序方式: 共有4848条查询结果,搜索用时 15 毫秒
1.
2.
《Clinical genitourinary cancer》2022,20(1):95.e1-95.e6
IntroductionThis study aimed to evaluate the concordance in tumor stage and grade between ureteroscopic (URS) biopsy and radical nephroureterectomy (RNU) in patients with upper tract urothelial carcinoma (UTUC).Patients and MethodsRecords of 1,214 UTUC patients who had undergone URS biopsy followed by RNU were included. Univariable and multivariable logistic regression analyses were performed to identify factors contributing to the pathological upstaging.ResultsThe concordance between URS biopsy-based clinical and RNU pathological staging was 34.5%. Clinical understaging occurred in 59.5% patients. Upstaging to muscle-invasive disease occurred in 240 (41.7%) of 575 patients diagnosed with ≤cT1 disease. Of those diagnosed with muscle-invasive disease on final pathology, 89.6% had been clinically diagnosed with ≤cT1 disease. In the univariable analyses, computed tomography urography (CTU)–based invasion, ureter location, hydronephrosis, high-grade cytology, high-grade biopsy, sessile architecture, age, and women sex were significantly associated with pathological upstaging (P < .05). In the multivariable analyses, CTU-based invasion and hydronephrosis remained associated with pathological upstaging (P < .05). URS biopsy-based clinical and pathological gradings were concordant in 634 (54.2%) patients. Clinical undergrading occurred in 496 (42.4%) patients.ConclusionsClinical understaging/undergrading and upstaging to muscle-invasive disease occurred in a high proportion of UTUC patients undergoing RNU. Despite the inherent selection bias, these data underline the challenges of accurate UTUC staging and grading. In daily clinical practice, URS biopsy and CTU offer the most accurate preoperative information albeit with limited predictive value when used alone. These findings should be considered when utilizing preoperative, risk-adapted strategies.  相似文献   
3.
4.
Objective: To assess the effect of electroacupuncture(EA) on expression of cytoskeletal proteins from Sertoli cells(SCs) and spermatogenesis in rats with oligozoospermia of insufficiency of Shen(Kidney)essence syndrome(OIKES).Methods: Twenty healthy male Sprague-Dawley rats were randomly assigned to four groups using a random number table: control,tripterygium glycosides(TG) treatment,sham and EA groups(n=5 in each group).A rat model of OIKES was established by oral gavage with TG.The EA group was treated with TG and received EA at Shenshu(BL 23) and Zusanli(ST 36) acupoints for 20 min,once daily for 30 days,while the sham group received EA at identical acupoints with skin penetration without stimulation.After 30 days,the ?nal body weight and coef?cients for the testis and epididymis were calculated and sperm parameters were measured.Immunohistochemical analyses were performed to detect expression of vimentin and α-tubulin in SCs and proliferating cell nuclear antigen(PCNA) immunoreactivity in germ cells.Apoptosis in germ cells was quanti?ed by the transferase biotin-dUTP nick end labeling assay.Results: Compared with the control group,the final body weight and testis/epididymis coefficients of rats in the TG-treated group were not significantly different,but the sperm count and motility were lower(P0.05).Expressions of vimentin and α-tubulin were also signi?cantly weaker(P0.01).The PCNA immunoreactivity of germ cells was decreased(P=0.059),whereas the apoptotic index of germ cells was increased signi?cantly(P0.01).In contrast,EA at BL 23 and ST 36 acupoints signi?cantly improved the ?nal body weight as well as the sperm count,concentration and motility(P0.01 or P0.05).EA increased expression of vimentin and α-tubulin in SCs markedly,and signi?cantly enhanced PCNA immunoreactivity with decreased apoptosis in germ cells(P0.01 or P0.05).Conclusions: EA at BL 23 and ST 36 acupoints has protective effects on spermatogenesis in rats with OIKES.This effect seems to be achieved by attenuating TG-induced disruption of cytoskeletal protein in SCs.  相似文献   
5.
6.
BackgroundRecently, the variability and heterogeneity of gender presentations in transgender youths have gained significant attention worldwide. Alongside this, specialized gender services have reported an increase in referrals of youths reporting non-binary identities. In Italy, studies investigating gender identity and expression in gender non-conforming youths are lacking, as are data regarding the non-binary population.AimThe present study aimed at dimensionally exploring how transgender and non-binary Italian adolescents identify and express their gender.OutcomesGender expression in trans binary youths and non-binary youths.MethodsThe Gender Diversity Questionnaire (GDQ; Twist & de Graaf, 2019) was used to investigate gender identity, gender fluidity, and gender expression in a sample of 125 adolescent patients from the Gender Identity Development Service (SAIFIP) in Rome and the Gender Incongruence Unit of the Careggi Hospital in Florence, between April 2019–June 2021.ResultsThe majority of participants (74.4%) identified as trans* binary and the remaining (25.6%) participants identified as non-binary. Trans binary participants reported a stable gender identity, whereas non-binary participants reported a more fluid gender identity across time and contexts. Almost all participants rated external appearance as important to their gender expression, yet trans binary participants attributed more importance to the body in this respect. Body discomfort and pubertal stage emerged as the most influential factors in participants’ experiences of gender. Participants who were assigned male at birth expressed significantly more desire for puberty blockers, whereas those who were assigned female at birth had a stronger desire to engage in breast/chest surgery. Non-binary participants sought different medical interventions relative to trans binary participants.Clinical ImplicationsThese results may be useful for clinicians working with transgender youths as they provide awareness regarding the features of young people who identify within and outside of binary constructions of gender.Strengths & LimitationsThis study provides useful data in gaining insight into understanding the variety of experiences and challenges of gender non-conforming youths. However as the sample was recruited from specialized services, it may not represent the entire gender non-conforming population in Italy.ConclusionThe results describe the range of gender identities and expressions among gender non-conforming youths attending gender specialized services in Italy, thereby improving our understanding of the variety of identities experienced and the specific medical needs of both trans binary and non-binary adolescents.Mirabella M, Piras I, Fortunato A, et al. Gender Identity and Non-Binary Presentations in Adolescents Attending Two Specialized Services in Italy. J Sex Med 2022;19:1035–1048.  相似文献   
7.
8.
Background: Intraductal carcinoma and cribriform (IDC/C) tumor features are well-established prognosticators of biochemical recurrence (BCR), metastasis, and prostate cancer (PCa)-specific mortality. However, approximately 70% of PCa patients undergoing a radical prostatectomy are IDC/C negative, yet up-to 20% of these patients progress and experience BCR. Thus, tumor histopathologic characteristics such as IDC/C alone are limited in their ability to predict disease progression. Conversely, several nomograms such as Cancer of the Prostate Risk Assessment-Surgery (CAPRA-S) have been developed to aid in the prognostication of BCR, but not yet widely applied in clinical settings. Materials and methods: In this study, we assessed the combined prognostic utility of IDC/C, and CAPRA-S for BCR in 3 PCa patient cohorts. Results: CAPRA-S+IDC/C improved the predictive accuracy of BCR in all 3 cohorts (P < .001). Specifically, among IDC/C negative cases, CAPRA-S improved the prognostication of BCR in low-risk (Cohort 1; P < .001, Cohort 2; P < .001, Cohort 3; P = .003), intermediate (Cohort 1; P < .001, Cohort 2; P = .006, Cohort 3; P = .03) and high-risk (Cohort 1-3; P < .001) patients. Conversely, IDC/C improved the prognostication of BCR among CAPRA-S low-risk (Cohorts 1; P < .001 and Cohort 3; P = .003) patients. Conclusion: Our results suggest the investigation of histopathological IDC/C features in CAPRA-S low-risk patients and conversely, nomogram CAPRA-S among IDC/C negative patients improves the identification of patients likely to experience BCR, which would otherwise be missed through current assessment regimens. These patients can be offered more intensive monitoring and adjuvant therapies upfront to circumvent the development of recurrent cancer or overtreatment at the time of surgery.  相似文献   
9.
BackgroundThe use of plaque incision and graft techniques (PIG) for the treatment of severe Peyronie's disease (PD), may lead to erectile dysfunction (ED); graft size is 1 of the contributing factors for post-PIG ED. Recently the iGrafter software APP was introduced using a mathematical algorithm to distribute the incisions along the penile length resulting in a smaller grafting area.AimCompare 2 PIG techniques, the Double-Y(DY) and iGrafter, in 3 main aspects: (i) Total grafting area; (ii) The variation in calculating the grafting to be used; (iii) time to perform the PIG.MethodsSix urologists with expertise in sexual medicine performed both techniques twice using four 3-D validated training models for PD with a standard 60° uniplanar dorsal curvature.OutcomesThe graft areas and operative partial and total time for each step of the operation were recorded for each procedure. Unpaired t-test and the coefficient of variation for graft area across surgeons was calculated comparing both techniques.ResultsFor all surgeons, the use of iGrafter resulted in 2 grafts, for the DY technique in 1 graft. Overall, TT for the iGrafter was significantly longer than for DY technique (49.4 ± 11 vs 40.7 ± 5.7 minute; P = .02), The iGrafter grafting area was significantly smaller (11.6 ± 1.2 vs 23.3 ± 5.4 cm2; P: .01), representing a 50.2% area reduction when compared to the DY. The variation of graft area, using the iGrafter also yielded a more consistent graft across all surgeons (CV = 10.56% vs 23.28%).Clinical SignificanceThe iGrafter, when compared to DY technique, reduced the graft area by 50%, which potentially means less erectile dysfunction.Strengths and LimitationsOur study eliminates anatomical variations found in a real clinical case making it possible to compare surgical techniques with the same penile anatomy. However, the 3D-printed model cannot replicate the living human tissue property preventing a simulation close to actual surgery.ConclusionThe use of the iGrafter software for PIG surgery has shown to be a promising technique for severe PD management resulting in smaller graft size (about 50% smaller when compared to the DY), although it might be more time-consuming.Tourchi A, Nascimento B, de Freita Miranda A, et al. Grafting Area Reduction in Peyronie's Disease Surgery: Comparative Assessment Between Double Y Vs iGrafter APP Using 3D-Printed Penile Models. J Sex Med 2022;19:669–675.  相似文献   
10.
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