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91.
Journal of Digital Imaging - Measurement of angles on foot radiographs is an important step in the evaluation of malalignment. The objective is to develop a CNN model to measure angles on...  相似文献   
92.
93.

Background

Anticoagulation increases the risk of intracerebral hemorrhage (ICH), yet whether different underlying disease processes are equally affected is unknown. We tested the hypothesis that coagulopathy, measured by admission international normalized ratio (INR), disproportionately increases the risk for lobar hemorrhages.

Methods

Patients with primary ICH were enrolled into a registry between December 2006 and February 2012 with prospective data acquisition and systematic follow up. Logistic regression was used to test whether lobar versus deep ICH location was independently associated with INR, and then whether INR had an influence on mortality. Spearman’s correlation coefficient was used to test for an association between INR and hematoma volume separately in the lobar and deep ICH groups.

Results

221 patients were studied. Patients with lobar ICH were older (71 vs. 62 years old, p < 0.001) and more likely to have prior ICH (10 vs. 0 %, p < 0.001). INR >1.4 was observed on admission more frequently in lobar versus deep ICH (19 vs. 8 %, p = 0.02). Lobar ICH location was independently associated with INR >1.4 (OR: 2.51, 95 % CI: 1.03–6.14, p = 0.043). ICH volume correlated with INR in lobar ICH (p = 0.009), but not deep ICH (p = 0.8). Death at 1 month was independently associated with INR >1.4 (OR: 7.6, 95 % CI: 2.4–24.1, p = 0.001) after correction for the ICH Score.

Conclusions

Abnormal coagulation occurs disproportionally in lobar versus deep ICH, and is associated with larger ICH volumes and higher mortality. These findings suggest a unique risk interaction between coagulopathy and underlying brain pathology due to cerebral amyloid angiopathy.  相似文献   
94.
IntroductionLatarjet procedure is commonly performed for recurrent anterior shoulder instability with glenoid side bone loss. Classic Latarjet procedure can be performed using specially designed drill guides, jigs, or by freehand technique. Here we have described a technical note on classic Latarjet procedure performed with freehand technique utilizing simple rulers and caliper. The functional and radiological outcomes of our patients have also been analysed.Material and Methods149 open classic Latarjet procedures were performed using our technique between March 2015 and July 2018. The mean age of the patients was 32.95 years (Range 22–59 years). The functional outcome of the patients was measured using Western Ontario Shoulder Instability (WOSI) and Oxford Shoulder Instability Score (OSIS) at 2 years of follow-up. Screw and graft positioning were studied in 24 consecutive patients with a postoperative computed tomography (CT) scan.ResultsThere was no incidence of recurrent subluxation or dislocation post-surgery. Mean OSIS score increased from 15.63 ± 3.20 preoperatively to 42.44 ± 3.88 postoperatively (p value < 0.05). WOSI score decreased significantly from 62.54% ± 8.24 to 10.26 ± 6.33 postoperatively at 2-year follow-up (p value < 0.05). Postoperative CT scan also showed satisfactory screw placement in all patients.ConclusionOpen Latarjet procedure performed using freehand technique provides good functional and radiological outcomes in patients with recurrent anterior shoulder instability with glenoid side bone loss.Supplementary InformationThe online version contains supplementary material available at 10.1007/s43465-021-00385-7.  相似文献   
95.
Direct-acting antiviral (DAA) therapy has transformed the management of human immunodeficiency virus (HIV) and hepatitis C (HCV) coinfected patients with advanced liver disease. STOP-Coinfection was a multicenter prospective and retrospective, open-label study using sofosbuvir-based DAA therapy to treat HIV/HCV-coinfected participants pre– or post–liver transplant (LT). Sixty-eight participants with end-stage liver disease (Child-Turcotte-Pugh score ≥7 and Model for End-Stage Liver Disease score 6–29) were enrolled, 26 had hepatocellular carcinoma. Forty-two participants were treated pre–LT and 26 post–LT. All participants completed therapy without need for dose reduction or transfusion; eight required two or more courses of therapy. Ninety-three percent achieved a sustained virologic response and DAA therapy was well tolerated. Despite HCV cure, 12 end-stage liver disease participants required subsequent LT, 7 for decompensated liver disease. Thirteen participants died, 10 with decompensated liver disease pre–LT and three post–LT. Overall, transplant free survival was 42.8% at 4 years and post–LT survival was 87.9% at 5 years. We conclude that sofosbuvir-based DAA therapy is safe and highly effective in HCV-HIV patients with decompensated liver disease and post–LT, with post–LT survival rates comparable to other indications. This removes one of the last barriers to liver transplantation in this challenging cohort of recipients.  相似文献   
96.
The purpose of this study was to assess the feasibility of PET imaging of oncogene VPAC1 receptors overexpressed in human breast cancer cells. METHODS: Vasoactive intestinal peptide (VIP) analog (TP3982) was synthesized to harbor a carboxy-terminus lysine (Lys) residue separated from VIP-asparagine (Asn(28)) by 4-aminobutyric acid (Aba) as a spacer. Lys was derivatized with diaminopropionic acid coupled to a pair of dibenzoylthioglycolic acid residues as protecting groups. The analog was labeled with (64)Cu at pH 9 ((64)Cu-TP3982) and (99m)Tc at pH 12 ((99m)Tc-TP3982). (99m)Tc-TP3982 and VIP derivatized with Aba-GAGG and labeled with (99m)Tc ((99m)Tc-TP3654) were used as reference agents. Smooth muscle relaxivity assays performed with each derivative and compared with unaltered VIP(28) demonstrated functional integrity. In vitro stability of (64)Cu-TP3982 was determined by challenging the complex with 100-mol excess of diethylenetriaminepentaacetic acid (DTPA), human serum albumin (HSA), and cysteine. In vivo stability was determined in urine and serum for up to 24 h. The mass of the Cu-TP3982 complex was determined by mass spectrometry. Human T47D breast tumor xenografts were grown in athymic nude mice. Planar scintigraphic imaging was performed at 4 and 24 h after the intravenous administration of (99m)Tc-TP3982 and (99m)Tc-TP3654 and PET imaging was performed using a small animal MOSAIC PET scanner, also at 4 and 24 h after injection of (64)Cu-TP3982. Tissue-distribution studies were also performed. In a separate experiment, receptors were blocked by intravenous injection of authentic VIP(28) 30 min before the administration of (64)Cu-TP3982 and tissue distribution was examined. RESULTS: (64)Cu-TP3982 labeling yields were 98% +/- 1.2% and those for (99m)Tc-TP3982 and (99m)Tc-TP3654 were 98.2% +/- 1.1% and 97% +/- 1.6%, respectively. The biologic activity of both VIP analogs was uncompromised. When (64)Cu-TP3982 was challenged with 100-mol excess of DTPA, HSA, or cysteine, >98% radioactivity remained as (64)Cu-TP3982. In vivo, >98% of (64)Cu circulating in plasma remained as (64)Cu-TP3982. Of the (64)Cu excreted in urine 4, 20, and 24 h after injection, >98%, 89.9% +/- 0.9%, and 85% +/- 3%, respectively, were bound to TP3982. The mass of Cu-TP3982 as determined by surface-enhanced laser desorption/ionization time of flight (SELDI-TOF) was 4,049.7 Da. Four hours after receptor blocking with VIP(28), there was a significant reduction in uptake of all tissues except in the liver. With (64)Cu-TP3982, the 4-h postinjection tumor uptake was 10.8 +/- 2.1 %ID/g versus 0.5 +/- 0.02 %ID/g and 0.24 +/- 0.08 %ID/g for (99m)Tc-TP3982 and (99m)Tc-TP3654, respectively. Twenty-four hours after injection, the corresponding numbers were 17 +/- 0.7 %ID/g, 0.77 +/- 0.1 %ID/g, and 0.23 +/- 0.1 %ID/g. The severalfold greater uptake (21.2-74) of (64)Cu-TP3982 is attributable to the in vivo stability of the agent. CONCLUSION: The results suggest that the uncompromised biologic activity and the significantly greater tumor uptake of (64)Cu-TP3982, combined with the high sensitivity and enhanced resolution of PET imaging, make (64)Cu-TP3982 highly desirable for further studies in PET imaging of oncogene receptors overexpressed in breast and other types of cancers.  相似文献   
97.
Artificial intelligence (AI) applications, in the form of machine learning and deep learning, are being incorporated into practice in various aspects of medicine, including radiation oncology. Ample evidence from recent publications explores its utility and future use in external beam radiotherapy. However, the discussion on its role in brachytherapy is sparse. This article summarizes available current literature and discusses potential uses of AI in brachytherapy, including future directions. AI has been applied for brachytherapy procedures during almost all steps, starting from decision-making till treatment completion. AI use has led to improvement in efficiency and accuracy by reducing the human errors and saving time in certain aspects. Apart from direct use in brachytherapy, AI also contributes to contemporary advancements in radiology and associated sciences that can affect brachytherapy decisions and treatment. There is a renewal of interest in brachytherapy as a technique in recent years, contributed largely by the understanding that contemporary advances such as intensity modulated radiotherapy and stereotactic external beam radiotherapy cannot match the geometric gains and conformality of brachytherapy, and the integrated efforts of international brachytherapy societies to promote brachytherapy training and awareness. Use of AI technologies may consolidate it further by reducing human effort and time. Prospective validation over larger studies and incorporation of AI technologies for a larger patient population would help improve the efficiency and acceptance of brachytherapy. The enthusiasm favoring AI needs to be balanced against the short duration and quantum of experience with AI in limited patient subsets, need for constant learning and re-learning to train the AI algorithms, and the inevitability of humans having to take responsibility for the correctness and safety of treatments.  相似文献   
98.
Malignant peripheral nerve sheath tumors (MPNST) are rare spindle-cell sarcomas derived from Schwann cells or pluripotent cells of the neural crest accounting for less than 10 % of all soft tissue sarcomas. They arise from major or minor peripheral nerve fibers or their sheaths. The World Health Organization coined the term MPNST for tumors of neurogenic origin with similar biological behavior replacing all the previous heterogeneous and, often, confusing nomenclature including malignant schwannoma, malignant neurilemmoma, and neurofibrosarcoma. The retroperitoneum and the lower extremities are the most common sites, but MPNST may arise anywhere in the body. Its location in the retroperitoneum in a patient without neurofibromatosis is an exceedingly rare occurrence. Imaging is routinely performed to assess the extent of the disease and to plan surgical resection. Surgical resection is the first line of therapy, ideally with total removal of the tumor. Owing to a high risk of recurrence with incomplete resection, postoperative irradiation and chemotherapy are necessary; however, they are often used as adjuvant therapy even if the tumor is completely resected.  相似文献   
99.

Objectives

To determine whether Helicobacter pylori (H. pylori) is detectable in both benign prostatic hyperplasia (BPH) and prostate cancer (PCa). Epidemiological studies have shown significant associations between infective chronic prostatitis and prostatic carcinoma. Many bacteria have been found in the prostate of patients with chronic prostatitis, BPH, and PCa.

Methods

One hundred consecutive patients with prostate diseases were enrolled in the study. Detection of H. pylori DNA in prostate tissue from patients with BPH and PCa was performed using both immunohistochemistry and PCR, and the results were confirmed by DNA sequencing. Odds ratios and the Fisher Exact test were used for the analysis of the associations between the variables.

Results

Among the patients, 78% had BPH and 19% had PCa. While immunohistochemistry showed no positive sample for H. pylori, PCR combined with sequencing detected H. pylori DNA in prostate tissue samples from 5 patients. However, statistical analysis of the data showed that BPH and PCa are not significantly associated with the presence of H. pylori DNA in prostate tissue (odds ratio = 0.94, 95% confidence interval = 0.09–23.34, one-tailed Chi-square value = 0.660, p > 0.05). The limitation of this study was the small number of PCa patients.

Conclusions

This study provides, for the first time, molecular evidence of the presence of H. pylori DNA in prostatic tissue of patients with BPH and PCa. It paves the way for further comprehensive studies to examine the association of H. pylori infection with BPH and PCa.Key Words: Helicobacter pylori infection, Prostate cancer, Benign prostate hyperplasia, PCR  相似文献   
100.
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