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51.
52.
We reviewed the pattern of involvement of the calvarium by tuberculosis (TB) in five patients and the role of imaging in
its management. Four patients presented with localised scalp swelling and one with generalized seizures. Radiographs revealed
lucent lesions with minimal surrounding sclerosis in the frontal (2), parietal (2) and occipital (1) bones. CT showed lesions
involving the entire thickness of the calvarium and accompanying contrast-enhancing soft tissue. The patient presenting with
seizures had a ring-enhancing lesion in the parietal lobe in addition to the extra-axial lesions. Although radiographs in
all cases demonstrated calvarial TB, CT showed the extent of the defect, involvement of adjacent soft tissues, and in one
case an intra-axial lesion. Radiographs suffice for follow-up of these patients.
Received: 23 July 1999 Accepted: 20 September 1999 相似文献
53.
Increased expression and secretion of interleukin-6 in patients with Barrett's esophagus. 总被引:6,自引:0,他引:6
54.
Stephen F Stanziale Henrik Petrowsky Prasad S Adusumilli Leah Ben-Porat Mithat Gonen Yuman Fong 《Clinical cancer research》2004,10(9):3225-3232
PURPOSE: The antitumor efficacy of a herpes simplex virus (HSV)-1 oncolytic virus depends on the cytotoxic effect of the virus, but also on viral replication and spread within the tumor. Apoptosis is considered a defense mechanism of infected cells that minimizes the spread of viral progeny by limiting cellular production of virus. We sought to determine whether oncolytic HSV-1 infection induces apoptosis in neighboring, uninfected cells and whether manipulation of apoptosis can increase viral replication and cytotoxicity. EXPERIMENTAL DESIGN: NV1066 is an oncolytic HSV-1 mutant that contains the marker gene for enhanced green fluorescent protein. OCUM human gastric cancer cells were infected with NV1066 in vitro and inspected for apoptosis by Hoechst and terminal deoxynucleotidyltransferase-mediated nick end labeling staining and for infection by expression of green fluorescence. RESULTS: A significant increase in apoptosis was seen in cells infected by NV1066. More interestingly, a significant percentage (10%) of uninfected cells also proceeded to apoptosis. After NV1066 infection, cells were also treated with N-acetylcysteine (NAC), an inhibitor of apoptosis. By day 4 after infection, 2.7x more NV1066 was produced in cells exposed to NAC than in those not exposed to NV1066 (P = 0.04). NAC also increased tumor kill when administered with virus. CONCLUSIONS: These data suggest that NV1066 induces apoptosis in uninfected cocultured cells, potentially hindering propagation of viral progeny and concomitant tumor kill. Inhibition of apoptosis may improve the efficacy of oncolytic HSV-1 therapy. 相似文献
55.
Richard J Wong Mei-Ki Chan Zhenkun Yu Ronald A Ghossein Ivan Ngai Prasad S Adusumilli Brendon M Stiles Jatin P Shah Bhuvanesh Singh Yuman Fong 《Clinical cancer research》2004,10(13):4509-4516
PURPOSE: Oncolytic herpes simplex viruses (HSVs) may have significant antitumor effects resulting from the direct lysis of cancer cells. HSVs may also be used to express inserted transgenes to exploit additional therapeutic strategies. The ability of an interleukin (IL)-12-expressing HSV to treat squamous cell carcinoma (SCC) by inhibition of tumor angiogenesis is investigated in this study. EXPERIMENTAL DESIGN: A replication-competent, attenuated, oncolytic HSV carrying the murine IL-12 gene (NV1042), its non-cytokine-carrying analog (NV1023), or saline was used to treat established murine SCC flank tumors by intratumoral injection. The expression of secondary antiangiogenic mediators was measured. Angiogenesis inhibition was assessed by in vivo Matrigel plug assays, flank tumor subdermal vascularity, and in vitro endothelial cell tubule formation assay. RESULTS: Intratumoral injections of NV1042 (2 x 10(7) plaque-forming units) into murine SCC VII flank tumors resulted in smaller tumor volumes as compared with NV1023 or saline. IL-12 and IFN-gamma expression in tumors was 440 and 2.2 pg/mg, respectively, at 24 h after NV1042 injection, but both IL-12 and IFN-gamma were undetectable (<0.2 pg/mg) after NV1023 or saline injections. Expression of two antiangiogenesis mediators, monokine induced by IFN-gamma and IFN-inducible protein 10, was elevated after NV1042 treatment. Matrigel plug assays of NV1042-transfected SCC VII tumor cells demonstrated significantly decreased hemoglobin content and microvessel density as compared with NV1023 and PBS. Excised murine flank tumors treated with NV1042 had decreased subdermal vascularity as compared with NV1023 and PBS. Both splenocytes and IL-12 expression by NV1042 were required for in vitro inhibition of endothelial tubule formation. CONCLUSIONS: IL-12 expression by an oncolytic herpes virus enhances therapy of SCC through antiangiogenic mechanisms. Strategies combining HSV oncolysis with angiogenesis inhibition merit further investigation for potential clinical application. 相似文献
56.
Tendon-to-bone healing of a semitendinosus tendon autograft used for ACL reconstruction in a sheep model 总被引:19,自引:0,他引:19
Goradia VK Rochat MC Grana WA Rohrer MD Prasad HS 《The American journal of knee surgery》2000,13(3):143-151
Anterior cruciate ligament (ACL) reconstruction was performed in a single hind limb of 30 sheep using a doubled semitendinosus tendon graft. Three additional animals were used as controls. Histologic and biomechanical analysis was performed from 4-52 weeks postoperatively. Perpendicular collagen fibers were found connecting the tendon graft to the bone tunnels at 8 weeks. These fibers were seen circumferentially at 12 weeks. By 24 weeks, the bone tunnel was well-defined, and no further changes were observed at 52 weeks. Tendon incorporation within the femoral and tibial tunnels was similar at each interval. Although the small sample size did not permit statistical testing, the reconstruction strength was similar up to 12 weeks (15%-19% of controls). This increased at 24 (28%) and 52 (40%) weeks. The stiffness primarily increased from 4-8 weeks (18%-39%) and 24-52 weeks (52%-82%). Up to 12 weeks, failures occurred by graft pull-out from the bone tunnel. All 24- and 52-week specimens ruptured through the intra-articular portion of the graft, further indicating sufficient graft incorporation within the bone tunnels. 相似文献
57.
58.
59.
Patankar T Krishnan A Patkar D Kale H Prasad S Shah J Castillo M 《Skeletal radiology》2000,29(7):392-396
Objective. To review imaging studies of isolated involvement of the sacrum due to tuberculosis and determine the role of imaging in
the diagnosis and management of these patients.
Design and patients. A retrospective analysis of 15 cases of isolated sacral tuberculosis imaged with MR imaging was performed. The CT images
were also reviewed where available, and the various lesion characteristics were identified. We also reviewed the medical records
in an attempt to determine the impact of the imaging studies on the management of these patients.
Results. Fifteen patients (5 male, 10 female) presented with symptoms of 3–15 months’ duration. Chronic localized backache with muscle
spasm was the commonest presenting symptom; discharging sinuses with abscess formation was found in six patients, five of
whom were children. MR imaging of the sacrum revealed a hypointense marrow signal on T1-weighted images and hyperintense signal
on T2-weighted images in 14 of 15 patients, the S2 vertebra being always involved. CT revealed osteolytic changes in the sacrum
in all the five patients in whom CT was performed. All patients showed marked clinical improvement within 1 year of anti-tuberculous
chemotherapy.
Conclusion. Isolated tuberculosis of the sacrum is uncommon but should be suspected in patients presenting with chronic low backache
or children with discharging sinuses/abscesses and showing sacral destruction on CT or MR imaging. MR imaging can identify
cases and enables early institution of anti- tuberculous chemotherapy.
Received: 31 August 1999 Revision requested: 1 November 1999 Revision received: 27 March 2000 Accepted: 14 April 2000 相似文献
60.
Gamma Surgery for Hemangiopericytomas 总被引:6,自引:0,他引:6
A retrospective analysis of a consecutive series of 12 patients with 15 intracranial hemangiopericytomas treated at the University of Virginia using Gamma surgery is presented. Clinical and radiographic follow up of 3 to 56 months is available for 10 patients with 12 tumors. There was one tumor present at the time of initial Gamma surgery in each patient. Two new tumors occurred in patients previously treated. Nine of the tumors decreased in volume and three remained stable. Four of the nine tumors that shrank later progressed at an average of 22 months after treatment. Of the tumors that decreased in volume and have not progressed, the response has been for an average of 11 months. The follow-up for two tumors that remained unchanged was 10 and 34 months (average 22 months). A third tumor was unchanged at 42 months but the patient died of new disease adjacent to the treated area in the anterior skull base. There were no complications and the quality of life following the procedure was maintained or improved in every case. Gamma surgery is effective in palliating the patients by decreasing tumor volume and delaying recurrence. 相似文献