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981.
During trophoblast invasion, luminal and glandular endometrial epithelial cells (EEC) have been found to undergo apoptosis through undetermined mechanisms. We postulate that nitric oxide (NO) and progesterone may mediate apoptosis in EEC because they are produced by trophoblasts at concentrations that can cause apoptosis in non-uterine cells. Using a cultured EEC line, RL95-2, we found that sodium nitroprusside (SNP) or S-nitroso-N-acetylpenicillamine (SNAP), two commonly used NO-releasing agents, caused the death of EEC in a dose-dependent manner and progesterone markedly enhanced NO-induced cytotoxicity. Cells treated with NO/progesterone showed a significant increase in the percentage of condensed nuclei, as detected by DAPI staining, and in caspase-3 activity, indicating that these cells underwent apoptosis. Immunoblot analysis revealed that SNP/NO could activate extracellular signal-regulated kinase (ERK) and, to a lesser extent, p38 mitogen-activated protein kinase (MAPK). While pretreatment with PD98059 (an ERK inhibitor) did not prevent cell death, the addition of SB203580 (a p38 MAPK inhibitor) effectively rescued the cells from NO/progesterone treatment. Moreover, SNP/NO-induced p38 MAPK activation was significantly up-regulated by progesterone. Our results demonstrate that NO and progesterone may synergistically activate p38 MAPK to induce apoptosis in EEC, a process that may facilitate implantation. 相似文献
982.
Hardee PS Carter JL Piper KM Ng SY 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2001,91(4):455-461
A young woman developed an unusual adenocarcinoma in each submandibular salivary gland at an interval of 30 months. This presentation has not been described previously. The possible etiology for this and treatment options are discussed. The choice of diagnostic imaging (ultrasound versus magnetic resonance imaging) is highlighted. As a result of regular follow-ups using diagnostic ultrasound, a second tumor was observed to reach a dimension of 8 mm in less than 6 months. This is probably the first report documenting the extent of initial growth of this rare tumor. 相似文献
983.
OBJECTIVE: The aim of this study was to investigate the feasibility of using DNA in the circulation as a diagnostic tool for cervical cancer. METHODS: We used PCR followed by Southern hybridization to detect human papillomavirus (HPV) DNA in serum samples taken from patients of cervical cancer before treatment. RESULTS: A total of 60 samples were analyzed. In a set of 40 samples, without knowledge of the HPV DNA status in the corresponding cervical carcinomas, we could detect 8 (20%) positive samples, of which 7 (17.5%) were HPV 16 and 1 (2.5%) was HPV 18. In another set of 20 samples, known to be HPV 16 infected in the corresponding cervical carcinomas, we detected only 4 (20%) HPV-16-positive samples. The occurrence of HPV DNA in sera of cervical cancer patients seems sporadic. CONCLUSION: The low incidence indicates that serum HPV DNA has limited application in the diagnosis of cervical cancer. 相似文献
984.
Loh TO Wang PH Yen MS Chao KC Ng HT Yuan CC 《European journal of gynaecological oncology》2001,22(6):420-422
PURPOSE: To identify local risk factors for FIGO IB, IIA and IIB bulky cervical squamous cell carcinoma (tumor size > or = 4 cm) patients with node-negative, margin-free tumors treated by radical hysterectomy, pelvic lymph node and para-aortic lymph node dissections without adjuvant therapies. MATERIALS AND METHODS: Thirty-four patients were recruited between 1976 and 1989 because they all declined any postoperative adjuvant therapy. The pathology reports showed that all the specimen margins were free from cancer cells with no para-aortic or pelvic lymph node metastases. The survival interval was calculated starting from the time of surgical intervention to the time of death or the end of this study in the year 2000. RESULT: Tumor variables including cell differentiation, depth of stromal invasion, parametrial invasion, vaginal invasion, uterine body invasion, age, and FIGO stage were analyzed. Only vaginal invasion showed statistical significance for decreasing patient disease-free survival in both univariate and multivariate analyses with p values of 0.003 and 0.002, respectively. CONCLUSION: For node-negative and margin-free patients with bulky cervical squamous cell carcinoma with operable stage IB and IIB, surgical intervention alone could suffice when no vaginal invasion is noted plus an 85% survival rate could be achieved. A prospective pilot study should be initiated although this study showed an excellent survival rate which is perhaps due to the limited number of cases. 相似文献
985.
986.
OBJECTIVE: To compare the functional performance of subjects with unilateral anterior cruciate ligament (ACL) reconstruction. DESIGN: Cross-sectional comparative clinical trial. SETTING: A physical therapy outpatient department. SUBJECTS: Thirty-one subjects with unilateral ACL reconstruction for more than 5 months. INTERVENTION: Patients under 3 bracing conditions: (1) DonJoy Brace, (2) mechanical placebo brace, or (3) no brace. Running and turning 10 times on a 22-meter figure-8 runway, and running and jumping (and landing) on a semicircular path. MAIN OUTCOME MEASURES: Speed of running and turning, speed of running and jumping, and accuracy of landing after the jump. RESULTS: Subjects performed similarly in conditions 1 and 2 in all the tests, but the speeds of running and turning were significantly slower in conditions 1 and 2 than condition 3 (p =.008--.000). Results of the run and jump tests were not different among all conditions. CONCLUSION: Knee bracing may not improve functional performance of subjects 5 months after ACL reconstruction. The use of such a brace could actually slow down running and turning, irrespective of the mechanical constraints of the brace. These functional outcomes need to be noted when such a brace is used on this group of subjects. 相似文献
987.
The Safe-Cross wire system, which has optical coherence reflectometry technology for navigating and radiofrequency energy provided at its tip for crossing chronic total occlusions (CTOs), provides a promising means to treat hard, organized CTOs. Using this system, we report on a 60% success rate in patients who had long-standing coronary CTOs that had > or =1 failed attempt using conventional percutaneous coronary intervention. 相似文献
988.
989.
Portal vein thrombosis after radiofrequency ablation for recurrent hepatocellular carcinoma 总被引:4,自引:0,他引:4
Ng KK Lam CM Poon RT Fan ST 《Asian journal of surgery / Asian Surgical Association》2003,26(1):50-3; discussion 54
Recurrent hepatocellular carcinoma (HCC) deserves multidisciplinary treatment in addition to surgical resection. Radiofrequency ablation (RFA) is an evolving, localized, thermal ablative treatment for unresectable hepatocellular carcinoma (HCC). Though the preliminary results of RFA in clinical studies are encouraging, its serious complications should not be underestimated. Portal vein thrombosis as a result of direct blood vessel injury by RFA is rarely reported and is potentially fatal in patients with limited liver reserve due to underlying liver cirrhosis. We present a case of portal vein thrombosis as a complication of RFA treatment for recurrent HCC and illustrate its underlying possible mechanism. 相似文献
990.