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991.
Glucal and galactal are transformed into 2-deoxyglycolactams, which are important building blocks in the synthesis of biologically active piperidine alkaloids, fagomine and 4-epi-fagomine. In one of the strategies, reduction of 2-deoxyglycolactam-N-Boc carbonyl by lithium triethylborohydride (Super-Hydride®) has been exploited to generate lactamol whereas reduction followed by dehydration was utilized as the other strategy to functionalize the C1–C2 bond in the iminosugar substrate. The strategies provide the formal synthesis of 2-deoxynojirimycin, nojirimycin and nojirimycin B. DFT studies were carried out to determine the reason for the failure of the formation of the 2-deoxygalactonojirimycin derivative. Further, DFT studies suggest that phenyl moieties of protecting groups and lone pairs of oxygen in carbamate group plays a vital role in deciphering the conformational space of the reaction intermediates and transition-state structures through cation–π or cation–lone pair interactions. The influence of these interactions is more pronounced at low temperature when the entropy factor is small.

Synthesis of fagomine, 4-epi-fagomine, formal synthesis of nojirimycin, nojirimycin B, & 2-deoxynojirimycin has been carried out using Super-Hydride reduction as a key step. DFT studies explain the failure of the reduction of galactolactam substrate.  相似文献   
992.
Infection caused by vancomycin resistant enterococci (VRE) leads to adverse outcome and is a real challenge. Despite increasing reports of VRE in different countries, there is scanty data on this issue from India. A total of 685 enterococci were isolated from various clinical samples from January to December 2004. Antimicrobial susceptibility was performed as prescribed by National Committee for Clinical Laboratory Standards (NCCLS). Vancomycin resistance was confirmed by minimum inhibitory concentration (MIC). Resistant phenotype was determined by Polymerase chain reaction (PCR). Of 685, 456 (67%) were E. faecalis and 229 (33%) were E. faecium. Resistance to various antibiotics in E. faecalis and E. faecium was as follows: ampicillin 33% and 54%, erythromycin 91% and 86%, ciprofloxacin 69% and 81%, tetracycline 50% and 54% and high level gentamicin resistance in 62% and 77% respectively. Vancomycin resistance was confirmed in 10 (1.4%) cases by MIC and all had Van A phenotype by PCR. Emergence of vancomycin resistant enterococci is of great concern because of its epidemic potential and scanty therapeutic options. Prompt diagnosis and efficient infection control measures can restrict its spread.  相似文献   
993.
Guided Fine‐Needle Aspiration Cytology (FNAC) as the first line investigation is not only useful in diagnosis of space occupying lesions but can also help in choosing appropriate management. This technique is most useful in diagnosing metastasis but is also helpful in excluding malignancy in some cases. Aim of this study is to analyze the spectrum of cytological diagnosis, adequacy, and clinicoradiological correlation of guided FNAC. The study was carried out in the departments of pathology and radiology for a period from January 2000 to November 2011. All the data were retrieved from hospital medical record section and departmental data bank and were analyzed. We have performed a total of 500 FNACs, including 234 under CT guidance and 266 under USG guidance. Among the CT‐guided FNACs, 87.6% (205 cases) had adequate material which included 152 malignant cases, 38 inflammatory cases and 15 benign cases. Among the cases under USG, 91.7% (244 cases) had adequate material comprising of 112 malignant cases, 44 inflammatory cases, and 88 benign lesions. It was noted that increased number of inadequate aspirate was from lesions with smaller size and increased depth. Out of total 264 malignant cases diagnosed on FNAC, 160 cases were identified as malignant on clinical and radiological findings. Guided FNAC is useful in deep seated lesions as well as in suspicious superficial lesions and is a safe diagnostic tool. If performed properly and correlated well with clinical and radiological findings, FNAC provides correct diagnosis in most cases. Diagn. Cytopathol. 2013;41:1052–1062. © 2012 Wiley Periodicals, Inc.  相似文献   
994.

Introduction

Mandibular reconstruction has changed significantly over the years and continues to evolve with the introduction of newer technologies and techniques.

Purpose

This article reviews the history of oromandibular reconstruction, biomechanics of mandible, summarizes the reconstruction options available for mandible with defect classification, goals in reconstruction, the various donor sites, current reconstructive options, dental rehabilitation and persistent associated problems.

Summary

Oromandibular reconstruction, although a challenge for the head and neck reconstructive surgeon, is now reliable and highly successful with excellent long-term functional and aesthetic outcomes with the use of autogenous bone grafts and current reconstructive options. The ideal reconstruction would provide a solid arch to articulate with the upper jaw, restoring swallowing speech, mastication, and esthetics. Autogenous vascularized bone grafts in combination with microsurgical techniques have revolutionized mandibular reconstruction in oral cancer surgery. Current trends in mandibular reconstruction aim to achieve reestablishment of a viable mandible of proper form and maxillary mandibular relationship while decreasing the need for invasive autogenous graft procurement. However the optimal reconstruction of mandibular defects is still controversial in regards to reconstructive options which include the donor site selection, timing of surgery and method of reconstruction.
  相似文献   
995.
996.
Arunachal Pradesh, a land of high mountains and dense forest, is home to many tribal communities, which comprise two thirds of the state’s population. Alcohol is one of the common addictive substances used traditionally among them despite much awareness about its harmful effect on health. The present study is focused on finding the association of religion, ethnicity, and demographic characteristics with alcohol use among some tribal communities in Changlang district of Arunachal Pradesh. A cross-sectional household survey was conducted on substance use in Changlang district of Arunachal Pradesh, India. A sample of 3,421 tribal respondents (1,795 males and 1,626 females) aged 15 years and older was extracted and analyzed. Sociodemographic differences in the prevalence of alcohol use among the tribes were analyzed and compared using the chi-square and t test. Multivariate logistic regression analysis was applied to identify the predictor variables of alcohol use. Data analysis indicates high prevalence of alcohol use (39.1%) among the tribes; and it was higher among males (49.3%) than among females (27.9%). Alcohol use was higher among Indigenous (65%) and Hindu (55.1%) religions compared with Buddhist (24.7%) and Christian (10%). It was also recorded high among Tangsa (42.0%) and Tutsa (76%) tribes compared with Singpho (13.6%) and Khamti (11.4%). High association of alcohol use among the tribal community with age, occupation, ethnicity, and religion was also recorded. Association of alcohol use with demographic characteristics, religion, and ethnic group shows the traditional and cultural belief in alcohol use persists among the tribes.  相似文献   
997.
Parkinson disease (PD) is highly prevalent among neurodegenerative diseases, affecting a diverse patient population. Despite a general willingness of patients to participate in clinical trials, only a subset of patients enroll in them. Understanding the barriers to trial participation will help to alleviate this discrepancy and improve trial participation. Underrepresented minorities, older patients, and patients with more medical comorbidities in particular are underrepresented in research. In clinical trials, this has the effect of delaying trial completion, exacerbating disparities, and limiting our ability to generalize study results. Efforts to improve trial design and recruitment are necessary to ensure study enrollment reflects the diversity of patients with PD. At the trial design level, broadening inclusion criteria, attending to participant burden, and focusing on trial efficiency may help. At the recruitment stage, increasing awareness, with traditional outreach or digital approaches; improving engagement, particularly with community physicians; and developing targeted recruitment efforts can also help improve enrollment of underrepresented patient groups. The use of technology, for virtual visits, technology-based objective measures, and community engagement, can also reduce participant burden and increase recruitment. By designing trials to consider these barriers to trial participation, we can improve not only the access to research for all our patients but also the quality and generalizability of clinical research in PD.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13311-020-00960-0.  相似文献   
998.
Laparoscopic and Minimally invasive techniques have become a routine practice for various surgical disorders in present times. Though, advanced laparoscopic procedures are feasible they are largely restricted to fewer centers due to lack of advanced instrumentation, finances and expertise at most of them. In this context, we conducted a feasibility study to evolve definite criteria for performing advanced laparoscopic surgeries in resource restricted set-ups. We present our experience with 25 cases of advanced laparoscopic procedures using conventional laparoscopic instruments. We evaluated the clinico-investigative profile and operative details of all the patients. We classified the surgical expertise, laparoscopic instrumentation, surgical set ups and patient factors systematically to evolve the criteria for feasibility of advanced laparoscopicsurgery. Out of the 22 eligible patients for the study, various laparoscopic surgeries performed were - Fundoplication (4), Cystogastrostomy (3), Endoscopic thyroidectomy (7), Thoracoscopic Thyroidectomy (2), Adrenalectomy (5) and Retroperitoneal paraganglioma excision (1). There was no mortality and two morbidities in the form of hypercarbia and a tracheo-cutaneous fistula in 2 cases of endoscopic thyroidectomy. According to the criteria, we propose our surgical set up falls in to Grade 3, for which this criteria fits in. This study demonstrates the feasibility of advanced laparoscopic procedures in semi-equipped set-up, preferably by employing institute specific criteria of CLASS.  相似文献   
999.
High voltage electrical contact to hand result in injuries at multiple levels that may require more than a single flap for effective coverage. We present here a simple technique to utilise preputial flap as an adjunct to groin flap in cases where simultaneous coverage was required at more than one site in hands. In the past two years, 15 patients with unilateral involvement of hands due to electrical contact injury underwent this procedure. In addition to a comfortable position of the hand, stable and purposeful coverage at the wrist and various areas of hands was achieved in all the patients and none had flap failure. Minor complications related to penile erection were encountered that resulted in partial wound dehiscence that was managed with resuturing, pain relief and temporary suppression of erection. In our opinion, preputial flap is a good addition in our armamentarium to be used alongside groin flap for effective coverage of more than a single site requiring flap cover in electric injuries of the hand.  相似文献   
1000.
Segmentation of the prostate boundary on clinical images is useful in a large number of applications including calculation of prostate volume pre- and post-treatment, to detect extra-capsular spread, and for creating patient-specific anatomical models. Manual segmentation of the prostate boundary is, however, time consuming and subject to inter- and intra-reader variability. T2-weighted (T2-w) magnetic resonance (MR) structural imaging (MRI) and MR spectroscopy (MRS) have recently emerged as promising modalities for detection of prostate cancer in vivo. MRS data consists of spectral signals measuring relative metabolic concentrations, and the metavoxels near the prostate have distinct spectral signals from metavoxels outside the prostate. Active Shape Models (ASM's) have become very popular segmentation methods for biomedical imagery. However, ASMs require careful initialization and are extremely sensitive to model initialization. The primary contribution of this paper is a scheme to automatically initialize an ASM for prostate segmentation on endorectal in vivo multi-protocol MRI via automated identification of MR spectra that lie within the prostate. A replicated clustering scheme is employed to distinguish prostatic from extra-prostatic MR spectra in the midgland. The spatial locations of the prostate spectra so identified are used as the initial ROI for a 2D ASM. The midgland initializations are used to define a ROI that is then scaled in 3D to cover the base and apex of the prostate. A multi-feature ASM employing statistical texture features is then used to drive the edge detection instead of just image intensity information alone. Quantitative comparison with another recent ASM initialization method by Cosio showed that our scheme resulted in a superior average segmentation performance on a total of 388 2D MRI sections obtained from 32 3D endorectal in vivo patient studies. Initialization of a 2D ASM via our MRS-based clustering scheme resulted in an average overlap accuracy (true positive ratio) of 0.60, while the scheme of Cosio yielded a corresponding average accuracy of 0.56 over 388 2D MR image sections. During an ASM segmentation, using no initialization resulted in an overlap of 0.53, using the Cosio based methodology resulted in an overlap of 0.60, and using the MRS-based methodology resulted in an overlap of 0.67, with a paired Student's t-test indicating statistical significance to a high degree for all results. We also show that the final ASM segmentation result is highly correlated (as high as 0.90) to the initialization scheme.  相似文献   
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