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91.
We have reported that metastatic human melanoma cells utilize the αvβ3 integrin to adhere to lymph node vitronectin (VN). In the present study, the adhesion of human and rat breast carcinoma cells to lymph node tissue was analyzed. We have previously shown a correlation between the metastatic potential of breast carcinoma cells and an RGD-mediated adhesion to cryostat sections of peripheral lymph nodes; this adhesion could be blocked by an antibody to the integrin β1 subunit. Here, we show that the metastatic breast carcinoma cell were significantly more adherent to fibronectin (FN) expressed by lymph node-derived stromal cells than non-metastatic cells. Metastatic cells also spread more rapidly than non-metastatic cells on FN-coated substrates. Using a combination of immunofluorescence microscopy, immunoprecipitation and blocking assays with integrin-specific antibodies, we found (i) that expression of the α3β1 integrin on metastatic mammary carcinoma cells was specifically increased in comparison to non-metastatic cells and (ii) that the α3β1 receptor was involved in the increased adhesion of metastatic cells to lymph node FN and in cell spreading on FN-coated substrates. Our data also suggest that the α5β1 integrin, which is also expressed on the metastatic cells, did not contribute to this increase in adhesion. Our data implicate the α3β1 integrin in adhesion to lymph node stromal cell FN and suggest that metastatic cells of different tissue origins (e.g., melanoma and breast carcinoma) may utilize distinct integrin-ligand combinations to colonize the same target organ. © 1996 Wiley-Liss, Inc.  相似文献   
92.
Utero-cutaneous fistula is a rare pathology. It mostly occurs consecutively to surgical intervention such as Cesarean section. Blood discharge from the cesarean scar during menstruation is a quasi-pathognomonic feature. Imaging modalities, particularly with the injection of contrast material through the cutaneous fistulous opening, confirm the diagnosis. The management is mainly surgical.We report the case of a utero-cutaneous fistula in a 27-year-old lady, with systemic lupus erythematosus. She presented seven months after her third cesarean section with pain and blood discharge from the cutaneous scar during menstruation for four months. A pelvic CT scan with the injection of the contrast material through the cutaneous fistulous opening confirmed the diagnosis of utero-cutaneous fistula. Surgical management was successful.  相似文献   
93.
ObjectivesThe eighth edition American Joint Committee on Cancer (AJCC) Staging incorporates significant changes to the seventh edition in the staging of oropharyngeal squamous cell carcinomas (OPSCC). An important change was the inclusion of OPSCC associated with the human papilloma virus (HPV). Our goal is to compare the performance of both staging systems for patients with HPV-selected and unselected clinical characteristics for OPSCC.MethodsUsing the Surveillance, Epidemiology, and End Results (SEER) database, 2004-2016, we identified patients with likely HPV-associated OPSCC based on surrogate markers (white males aged <65 years old with squamous cell carcinomas of the tonsil and base of tongue), excluding those who underwent surgery. We re-classified these patients using seventh and eighth edition staging for HPV-selected OPSCC and compared the prediction performance of both staging editions for overall survival (OS) and disease-specific survival (DSS). We performed the same analysis for clinically unselected patients with OPSCC.ResultsOur analysis included 9554 patients with a median follow-up of 67 months. Comparing the eighth versus seventh edition for our HPV-selected cohort, clinical staging changed for 92.3% of patients and 10-year OS was 62.2%, 61.2%, 35.3%, and 15.5% for Stage I, II, III, and IV, versus 52.9%, 59.2%, 61.6%, 55.1%, 38.3%, and 15.5% for stage I, II, III, IVA, IVB, and IVC, respectively. A similar pattern was observed for 10-year DSS. The concordance statistics for our HPV-selected cohort were improved for both AJCC 7 (0.6260) and AJCC 8 (0.6846) compared with the unselected cohort, 0.5860 and 0.6457 for AJCC 7 and 8, respectively.ConclusionThe overall performance of discrimination improved from AJCC 7 to AJCC 8 for both clinically selected and unselected patients, but more notably for our HPV-selected cohort. Despite the lack of statistically significant differentiation between Stages I and II in AJCC 8 in either groups, markedly improved discrimination was observed between Stages I/II, III, and IV in the HPV-selected cohort.  相似文献   
94.
95.
European Archives of Oto-Rhino-Laryngology - Oral squamous cell carcinoma (SCC) is characterized by a high risk of cervical lymph node metastasis with a high incidence of occult metastasis. A...  相似文献   
96.
Purpose: Radiotherapy is a very effective tool in the treatment of painful bone metastases. The aim of this study was to compare the palliative effect of radiotherapy between the standard fractionation schedule 20 Gy over 5 fractions (20Gy/5fr) and the high biological dose schedule 27 Gy over 3 fractions (27Gy/3fr) which is frequently used in Stereotactic body radio-surgery (SBRT). Methods: Patients were randomized to receive (20Gy/5fr)or (27Gy/3fr). The primary aim of the study was pain relief using the numeric rating scale (NRS), after three months of radiation therapy. Secondary end points include pain relief immediately after finishing radiation therapy (within one week), and narcotic relief after three months of radiation therapy. Results: Twenty-two patients with painful bone metastases were included. 12 patients received (20Gy/5fr) and 10 patients received (27Gy/3fr). Male patients were predominant on both arms (81.8%) with a mean age of 58 years [ranging between 19-72 years]. For pain relief after three months of radiation therapy, partial pain relief was documented in 9 patients (75%) with (20Gy/5fr) and in 8 patients (80%) with (27Gy/3fr) with a p- value of 0.6. Additionally, narcotic relief after three months was equal for both groups. For immediate pain relief, partial pain relief was seen in one patient (8%) with (20Gy/5fr) versus seven patients (70%) with (27Gy/3fr) with a p value of 0.06. The increase in immediate pain relief in the 27Gy arm was numerically but not statistically significant. Conclusion: SBRT and standard fractionation radiation therapy had equal effectiveness for pain relief, when the assessment was done after three months of radiation therapy. Interestingly, SBRT had a better immediate pain relief.  相似文献   
97.
Molecular cosensitization is favorable for manipulating solar radiation through the judicious choice of cosensitizers having complementary absorption spectra. For greenhouse-integrated dye-sensitized solar cells (DSCs), the manipulation of solar radiation is crucial in order to maximize the flow of photosynthetically active radiation (PAR) for the effectual photosynthetic activity of plants; meanwhile, non-PAR is utilized in agrivoltaics for generating electricity. In this study, we report the synthesis of novel four UV-selective absorbers, based on the diimide scaffold, functionalized with carboxylate and pyridyl anchoring groups, for adequate adsorption onto the TiO2 electrode in DSC. The UV/Vis absorption spectra of the DMF solution-based free dyes were measured experimentally. Basic photophysical and energetics requirements for operating greenhouse-integrated DSCs were examined at the molecular level via (time-dependent) density functional theory-based calculations. The computational results revealed the outperformance of the biphenyldiimide-structured DI-CA1 dye, especially for maximum charge transferred to its anchor, lower thermodynamic barrier for dissociating the photogenerated exciton, largest Stokes'' shift, strong electronic coupling with TiO2 nanoparticles, and higher degree of charge separation at the DI-CA1/TiO2 interface. PDOS showed deeper existence for the LUMO level in the CB of TiO2, which expedites the electron injection process. The chemical and optical compatibility of DI-CA1 were then investigated as a potential cosensitizer of a reference BTD–DTP1, a green light-absorbing dye. Considerable overlap between the fluorescence spectrum of DI-CA1 and absorption spectrum of the reference BTD–DTP1 advocated the opportunity of excitation energy transfer via the radiative trivial reabsorption mechanism, which confirms the cosensitization functionality. Energy decomposition analysis and reduced density gradient maps estimated the chemical compatibility owing to weak dispersion interactions as the dominant stabilizing attractive force. This noncovalent functionalization retains the chemical compatibility without distorting the π–π conjugation and the associated physicochemical properties of the individual dye molecules. Along with the expanded consumption of non-photosynthetically active solar radiation, an improved power conversion efficiency of greenhouse-integrated DSC is accordingly expected.

Molecular cosensitization is favorable for manipulating solar radiation through the judicious choice of cosensitizers having complementary absorption spectra.  相似文献   
98.
The anterior liver hernia is a very rare entity that mainly occurs within an incisional hernia. Primary anterior liver hernia, in the absence of a previous abdominal incision, is extremely rare. The diagnosis is suspected in patients with epigastric bulging. The confirmation requires imaging studies such as computed tomography scan (CT scan). We report the case of an incarcerated primary ventral liver hernia, in an 83-year-old man who presented with a sudden epigastric swelling. A contrast-enhanced CT scan confirmed the diagnosis of incarcerated epigastric hernia with liver and epiploic content. Risk factors were thought to be the increased intra-abdominal pressure related to benign prostate hyperplasia, as well as the old age of the patient. The surgical conservative management was successful.  相似文献   
99.
Background and study aimsAscites may be of undetermined origin despite comprehensive study. This study aimed to assess the accuracy and safety of conventional and interventional high-frequency peritoneal ultrasound in the diagnosis of patients with ascites of unclear origin.Patients and methodsA total of 62 patients were prospectively enrolled; they underwent conventional (3.5–5 MHz) and high-frequency (6–8 MHz) transabdominal peritoneal ultrasound to suggest the nature of ascites supplemented by fine needle aspiration cytology (FNAC) of ascites and/or core biopsy of the omentum or other extra-visceral masses for final histopathologic diagnosis. Laparoscopy or laparotomy was needed if biopsy was inconclusive.ResultsUltrasound-guided procedures were diagnostic in 55 (87.7%) patients. Thirty-six (58.1%) were benign, of whom 86% had tuberculous peritonitis, 26 (41.9%) were malignant, of whom 76.9% had peritoneal metastasis. High-frequency ultrasound was able to propose ultrasonographic criteria in a trial to diagnose the nature of ascites. Our proposed ultrasonographic criteria were based on the amount and texture of ascites in addition to the omental and mesenteric features. These were able to suggest the diagnosis with 80.7% sensitivity for malignant ascites and 75% specificity for benign ascites. Moreover, histopathological examination of tissues obtained by ultrasound-guided procedures increased the sensitivity to 88.5% and the specificity to 88.9% in diagnosing malignant and benign disease, respectively, with an overall diagnostic accuracy of 88.6%. These procedures were considered to be safe as only one major (haemoperitoneum) and two minor complications (temporary ascitic fistula) were reported.ConclusionHigh-frequency peritoneal ultrasound together with the minimally invasive ultrasound-guided FNAC/biopsy of extra-visceral lesions may be considered an effective and safe tool in the diagnosis of ascites of undetermined origin.  相似文献   
100.
Objective: This study was done to evaluate the antibacterial effect of chitosan nano-particles (CNPs) root canal irrigant as a new alternative to Sodium hypochlorite (NaOCl) for disinfection of root canals inoculated with Enterococcus faecalis, with and without laser activation.

Methodology: Sixty single rooted human premolars were decoronated, prepared and had their apical foramina sealed. E. faecalis were incubated in the root canals for 15 days. The teeth were then randomly divided into two experimental groups (n?=?30) according to the disinfection protocol used. In Group I: disinfection was performed using the irrigant solutions only (Saline, 2.5% NaOCl, CNPs). Whereas in Group II, disinfection was done using the same irrigants followed by Diode laser at (980-nm) at 2 W output for 5?×?5?s. Intra-canal bacterial samples were taken before and after canal disinfection to determine the CFU count.

Results: In group I, 2.5% NaOCl was as effective as CNP in eradication and significantly more effective than Saline (p?=?0.008) in eradication of E. faecalis. In Group II, either 2.5% NaOCl or CNP in combination with diode laser irradiation showed a similarly high effect in bacterial eradication.

Conclusions: Within the parameters used in this study, a combination therapy consisting of irrigation followed by diode laser irradiation should be utilized as an effective treatment modality for eliminating E. faecalis from root canal systems.  相似文献   
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