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991.
Kuehnemund M  Bootz F 《Head & neck》2006,28(11):1046-1048
BACKGROUND: This is a case report about a rare hypopharyngeal foreign body causing dysphagia, dyspnea, and hemoptysis as well as melena: an ingested leech. The patient was in this condition for more than 1 week. METHODS: The ingested leech, attached to the right piriform fossa partially obstructing the larynx, had to be removed under general anesthesia. RESULTS: After removal, no further symptoms occurred. The leech was identified as the species Theromyzon tessulatum. CONCLUSIONS: Human infestation of a leech in the upper aerodigestive tract is a very rare condition in urban areas. The current literature is reviewed and the diagnostic approach as well as therapeutic options are discussed.  相似文献   
992.
BACKGROUND: Orthotopic transplantation of intestinal mucosal organoids that contain putative mucosal stem cells serves as an important step toward implementing intestinal gene therapy and treatment for malabsorption syndromes in animals and humans. We hypothesized that intestinal mucosal organoids can be transplanted along the axis of the small bowel giving rise to a neomucosa expressing proteins of its donor origin. METHODS: Epithelial organoids were harvested from neonatal mice or rat small intestine with the use of a combination of enzymatic digestion with dispase and collagenase, and gravity sedimentation. In adult syngeneic recipients, a 7-cm segment of midjejunum was isolated, leaving its vascular pedicle intact. The remaining proximal and distal segments were anastomosed to restore intestinal continuity. The isolated segments were randomly subjected to surgical or chemical mucosectomy with a chelator solution for 30, 45, or 60 minutes and then compared. Histologic examination was used to confirm the presence of enterocytes, goblet cells, enteroendocrine cells, and Paneth cells in the neomucosal segments. To confirm the presence of ileal bile acid transporter (IBAT) gene message and function, we measured sodium-dependent bile acid uptake and IBAT-messenger RNA. Immunohistochemical examination using anti-IBAT antibodies was performed to demonstrate the expression of IBAT in the neomucosal segments. Experiments were repeated in a murine model transgenic for the green fluorescent protein to verify donor origin of the engrafted mucosa expressing IBAT. RESULTS: The area of peak IBAT function was found to be located in the terminal ileum. Organoid units harvested from this region were capable of generating a small-bowel neoileal mucosa after being seeded into the jejunum. This mucosa was histologically confirmed to differentiate into all 4 intestinal lineages and to express IBAT signal, confirming its donor-derived origin. Optimal engraftment of mucosa expressing the IBAT protein was found in isolated jejunal segments debrided for 45 minutes. Sodium-dependent bile acid uptake was 5-fold higher in the neoileum, compared with the jejunum. IBAT-mRNA levels in the neoileum were 18-100-fold higher than those in the jejunum. Areas of green fluorescent protein-positive mucosa stained positively with anti-IBAT antibody in adjacent sections, suggesting that the regenerated mucosa is from transplanted ileal stem cells. CONCLUSIONS: Orthotopic transplantation of epithelial organoids containing ileal stem cells was used to generate a neoileal mucosa that expressed all 4 intestinal lineages along with a new zone of active bile acid uptake and IBAT expression in a recipient jejunal segment.  相似文献   
993.
BackgroundInjury to kidney podocytes often results in chronic glomerular disease and consecutive nephron malfunction. For most glomerular diseases, targeted therapies are lacking. Thus, it is important to identify novel signaling pathways contributing to glomerular disease. Neurotrophic tyrosine kinase receptor 3 (TrkC) is expressed in podocytes and the protein transmits signals to the podocyte actin cytoskeleton.MethodsNephron-specific TrkC knockout (TrkC-KO) and nephron-specific TrkC-overexpressing (TrkC-OE) mice were generated to dissect the role of TrkC in nephron development and maintenance.ResultsBoth TrkC-KO and TrkC-OE mice exhibited enlarged glomeruli, mesangial proliferation, basement membrane thickening, albuminuria, podocyte loss, and aspects of FSGS during aging. Igf1 receptor (Igf1R)–associated gene expression was dysregulated in TrkC-KO mouse glomeruli. Phosphoproteins associated with insulin, erb-b2 receptor tyrosine kinase (Erbb), and Toll-like receptor signaling were enriched in lysates of podocytes treated with the TrkC ligand neurotrophin-3 (Nt-3). Activation of TrkC by Nt-3 resulted in phosphorylation of the Igf1R on activating tyrosine residues in podocytes. Igf1R phosphorylation was increased in TrkC-OE mouse kidneys while it was decreased in TrkC-KO kidneys. Furthermore, TrkC expression was elevated in glomerular tissue of patients with diabetic kidney disease compared with control glomerular tissue.ConclusionsOur results show that TrkC is essential for maintaining glomerular integrity. Furthermore, TrkC modulates Igf-related signaling in podocytes.  相似文献   
994.
CRADLE was a 36-month multicenter study in pediatric (≥1 to <18 years) kidney transplant recipients randomized at 4 to 6 weeks posttransplant to receive everolimus + reduced-exposure tacrolimus (EVR + rTAC; n = 52) with corticosteroid withdrawal at 6-month posttransplant or continue mycophenolate mofetil + standard-exposure TAC (MMF + sTAC; n = 54) with corticosteroids. The incidence of composite efficacy failure (biopsy-proven acute rejection [BPAR], graft loss, or death) at month 36 was 9.8% vs 9.6% (difference: 0.2%; 80% confidence interval: −7.3 to 7.7) for EVR + rTAC and MMF + sTAC, respectively, which was driven by BPARs. Graft loss was low (2.1% vs 3.8%) with no deaths. Mean estimated glomerular filtration rate at month 36 was comparable between groups (68.1 vs 67.3 mL/min/1.73 m2). Mean changes (z-score) in height (0.72 vs 0.39; P = .158) and weight (0.61 vs 0.82; P = .453) from randomization to month 36 were comparable, whereas growth in prepubertal patients on EVR + rTAC was better (P = .050) vs MMF + sTAC. The overall incidence of adverse events (AEs) and serious AEs was comparable between groups. Rejection was the leading AE for study drug discontinuation in the EVR + rTAC group. In conclusion, though AE-related study drug discontinuation was higher, an EVR + rTAC regimen represents an alternative treatment option that enables withdrawal of steroids as well as reduction of CNIs for pediatric kidney transplant recipients. ClinicalTrials.gov: NCT01544491.  相似文献   
995.
We longitudinally assessed erectile function as well as the willingness to use pro-erectile treatment in a cohort on AAT for advanced RCC. Thirty-seven patients with advanced RCC completed the five-item version of the International Index of Erectile Function (IIEF-5) and other interview items before (T0) and 12 weeks into therapy (T12) with AAT. Patients were further asked if they were willing to use and pay out-of-pocket for on-demand treatment with phosphodiesterase-5-inhibitors (PDE-5i). Statistical analysis was performed using nonparametric hypothesis testing. The IIEF-5 score at T12 was significantly decreased compared with T0 (p < .001). Subjective patient satisfaction regarding their sexual lives was associated with higher IIEF-5 scores at both time points (p = .006 and p = .03, respectively). At T12, subjective sexual contentment showed a nonsignificant trend towards decline (p = .074). Patients who opted for medical treatment of ED showed significantly better IIEF-5 scores at both time points compared with the rest of the cohort (p < .001 and p = .005, respectively). In summary, AAT seems to have a negative effect on erectile function in RCC patients, however, the role of psychosocial issues warrants further elucidation. Affected patients may benefit from a proactive approach promoting medical treatment of erectile dysfunction during AAT.  相似文献   
996.
The number of patients returning to dialysis after graft failure increases. Surprisingly, little is known about the clinical and immunological outcomes of this cohort. We retrospectively analyzed 254 patients after kidney allograft loss between 1997 and 2017 and report clinical outcomes such as mortality, relisting, retransplantations, transplant nephrectomies, and immunization status. Of the 254 patients, 49% had died 5 years after graft loss, while 27% were relisted, 14% were on dialysis and not relisted, and only 11% were retransplanted 5 years after graft loss. In the complete observational period, 111/254 (43.7%) patients were relisted. Of these, 72.1% of patients were under 55 years of age at time of graft loss and only 13.5% of patients were ≥65 years. Age at graft loss was associated with relisting in a logistic regression analysis. In the complete observational period, 42 patients (16.5%) were retransplanted. Only 4 of those (9.5%) were ≥65 years at time of graft loss. Nephrectomy had no impact on survival, relisting, or development of dnDSA. Patients after allograft loss have a high overall mortality. Immunization contributes to long waiting times. Only a very limited number of patients are retransplanted especially when ≥65 years at time of graft loss.  相似文献   
997.
998.
ObjectiveTo assess the lymphatic vessel density (LVD) and lymphangiogenesis in urothelial carcinoma of the bladder (UCB) and to identify predictors of progression in patients treated by transurethral resection (TUR).Materials and methodsOne hundred eleven patients who underwent TUR for UCB were retrospectively included. Lymphatic endothelial cells were stained immunohistochemically [D2-40 (podoplanin) antibody in all samples; Prox-1, LYVE-1, and VEGFR-3 (Flt-4) in subgroups]. LVD was measured in representative intratumoral (ITLVD), peritumoral (PTLVD), and nontumoral (NTLVD) areas using standardized criteria. Double-immunostainings with D2-40/CD-34 were performed to distinguish between blood and lymphatic vessels, and D2-40/Ki-67 stainings were done to detect lymphangiogenesis. Lymph-specific parameters were correlated with pathologic and clinical characteristics. In patients with non-muscle-invasive UCB (n = 76) univariable and multivariable analyses were performed to identify predictors of progression.ResultsThe PTLVD was significantly higher than ITLVD and NTLVD (P < 0.001). Proliferating lymphatic vessels were observed in all specimens assessed with D2-40/Ki-67. Characteristic suburothelial D2-40 positivity was observed in noninvasive pTa tumors. LYVE-1-stainings revealed the existence of tumor-associated macrophages. The presence of intratumoral lymphatic vessels was significantly associated with higher tumor stage, high grade, and sessile growth (all P < 0.001). Muscle-invasive tumors (P = 0.020), higher grade (P = 0.026), the presence of lymphovascular invasion (P < 0.001), and concomitant carcinoma in situ (CIS) (P = 0.020), sessile growth (P = 0.004), and loss of suburothelial D2-40 positivity (P = 0.031) were associated with disease progression in univariable analysis. LVD values in any area were not significantly associated with progression despite detection of proliferating lymphatic vessels. The presence of concomitant CIS was identified as an independent predictor of progression on multivariable analysis (P = 0.041; hazard ratio 4.620).ConclusionsA high peritumoral LVD is present in clinically localized UCB. The presence of intratumoral lymphatic vessels correlates with characteristics of aggressive disease. Lymphangiogenesis occurs; however, the lymph-specific parameters tested in this study cannot be used to predict progression following TUR. The presence of concomitant CIS is an important risk factor for later disease progression in patients with non-muscle-invasive UCB. Our results contribute to the understanding of metastatic tumor spread in UCB.  相似文献   
999.
1000.
Background contextClosed reduction and internal fixation by an anterior approach is an established option for operative treatment of displaced Type II odontoid fractures. In elderly patients, however, inadequate screw purchase in osteoporotic bone can result in severe procedure-related complications.PurposeTo improve the stability of odontoid fracture screw fixation in the elderly using a new technique that includes injection of polymethylmethacrylat (PMMA) cement into the C2 body.Study designRetrospective review of hospital and outpatient records as well as radiographs of elderly patients treated in a university hospital department of orthopedic surgery.Patient sampleTwenty-four elderly patients (8 males and 16 females; mean age, 81 years; range, 62–98 years) with Type II fractures of the dens.Outcome measuresComplications, cement leakage (symptomatic/asymptomatic), operation time, loss of reduction, pseudarthrosis and revision surgery, patient complaints, return to normal activities, and signs of neurologic complications were all documented.MethodsAfter closed reduction and anterior approach to the inferior border of C2, a guide wire is advanced to the tip of the odontoid under biplanar fluoroscopic control. Before the insertion of one cannulated, self-drilling, short thread screws, a 12 gauge Yamshidi cannula is inserted from anterior and 1 to 3 mL of high-viscosity PMMA cement is injected into the anteroinferior portion of the C2 body. During polymerization of the cement, the screws are further inserted using a lag-screw compression technique. The cervical spine then is immobilized with a soft collar for 8 weeks postoperatively.ResultsAnatomical reduction of the dens was achieved in all 24 patients. Mean operative time was 64 minutes (40–90 minutes). Early loss of reduction occurred in three patients, but revision surgery was indicated in only one patient 2 days after primary surgery. One patient died within the first eight postoperative weeks, one within 3 months after surgery. In five patients, asymptomatic cement leakage was observed (into the C1–C2 joint in three patients, into the fracture in two). Conventional radiologic follow-up at 2 and 6 months confirmed anatomical healing in 16 of the19 patients with complete follow-up. In two patients, the fractures healed in slight dorsal angulation; one patient developed a asymptomatic pseudarthrosis. All patients were able to resume their pretrauma level of activity.ConclusionsCement augmentation of the screw in Type II odontoid fractures in elderly patients is technically feasible in a clinical setting with a low complication rate. This technique may improve screw purchase, especially in the osteoporotic C2 body.  相似文献   
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