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991.
We studied the possibility that cryopreserved human heart cells could be transplanted with some advantage. METHOD: Cells derived human atrial tissues (control group (n = 13)), cryopreserved cells (cell-cryopreservation group (n = 23), and cells derived cryopreserved tissue (tissue-cryopreservation group (n = 29)) were cultured for 15 days. The cell proliferation was compared between control and cryopreservation group by growth curves. BasicFGF, TGFbeta-1, IL-6, IL-8, and cell cycle were measured at pre and post-cryopreservation. Mixed Lymphocyte-heart cell culture established by PBL and heart cells was evaluated by PBL proliferation. Transplanted cells were evaluated by visually and histology. RESULTS: Cryopreserved cells were proliferated much more than control cells (p < 0.0001). The growth factors were increased, and cytokines were decreased by cryopreservation (p < 0.05). The cryopreserved cell cycles were shifted to G2 + M from G1 + G0 period. Cryopreserved cells stimulated PBL less than non-cryopreserved cells (p < 0.0001). Transplanted cryopreserved cell were survived. CONCLUSION: Cryopreserved human heart cells can be transplanted, and proliferated much more than non-cryopreserved cells. Cryopreservation enables the human cells to be more prolific, and reduced the immunogenicity of them. The transplanted cryopreserved cells survived and formed cardiac-like tissue.  相似文献   
992.
A decrease in renal synthesis of nitric oxide (NO) in the progression of diabetic nephropathy has been documented. As (6R)-5,6,7,8-tetrahydrobiopterin (BH4) is an essential cofactor of NO synthase, we investigated whether BH4 deficiency is involved in the pathogenesis of nephropathy. Ten-week-old Otsuka Long-Evans Tokushima Fatty (OLETF) rats were used as a type II diabetic model, and Long-Evans Tokushima Otsuka (LETO) rats as the healthy controls. OLETF rats were orally treated with BH4 (10 mg/kg daily) or with water from 10 to 61 weeks of age. In another experiment, OLETF rats were treated orally with a calcium channel blocker, benidipine (5 mg/kg daily), or with 0.3% carboxymethyl cellulose (nontreated) from 10 to 52 weeks of age. Proteinuria was observed periodically, and at the end of the study, BH4 level and GTP cyclohydrolase I (GTPCH) activity in the kidney were measured. Proteinuria was observed at 13 weeks of age in the OLETF rats, and deteriorated until 61 weeks of age. Supplemental BH4 reduced the proteinuria. At 52 weeks of age, GTPCH activity and the BH4 level were decreased in the plasma and kidneys of OLETF rats, whereas they were significantly higher in the benidipine group than in the nontreated group. Proteinuria was milder in the benidipine group than in the nontreated group, without a concomitant decrease in blood pressure. Histologically observed glomerulosclerosis was mild in the BH4 and benidipine groups. In type II diabetic rats, renal BH4 is considered to play a crucial role in the pathogenesis of diabetic nephropathy. Benidipine was found to preserve BH4 levels, suggesting therapeutic renoprotective effects.  相似文献   
993.
Meta-analysis of antiplatelet therapy for IgA nephropathy   总被引:1,自引:0,他引:1  
Background Antiplatelet agents have been widely used in the management of immunoglobulin A (IgA) nephropathy in the Japanese population. To systematically evaluate the effects of antiplatelet agents for IgA nephropathy, we conducted a meta-analysis of the published studies. Methods Data sources consisted of MEDLINE, EMBASE, the Cochrane Library, Ityu-shi (Japanese medical database), and bibliographies from the studies. The quality of the studies was evaluated from the intention to treat analysis and allocation concealment, as well as by the Jadad method. Meta-analyses were performed on the outcomes of proteinuria and renal function. Results Seven articles met the predetermined inclusion criteria. The use of antiplatelet agents showed statistically significant effects on proteinuria and renal function. The pooled risk ratio for proteinuria was 0.61 (95% confidence intervals (CI) 0.39–0.94) and for renal function it was 0.74 (95% CI 0.63–0.87). Conclusions Antiplatelet agents resulted in reduced proteinuria and protected renal function in patients with IgA nephropathy. However, studies of high-quality design were rare, and most studies assessed surrogate outcomes. More properly designed studies are needed to reach a definitive assessment of this matter.  相似文献   
994.
995.
In this study, we have developed an implantable electronics unit (IEU) for driving an undulation pump-left ventricular assist device (UP-LVAD). The IEU consists of a pump driver, three series-connected lithium ion batteries (1800 mAh), a charger, and a transcutaneous information transmission system. These electronic subunits were encapsulated in a case (110 x approximately 80 x approximately 30 mm) made of epoxy resin. The IEU was evaluated in two animal experiments using goats implanted with the UP-LVAD. The lithium ion batteries in the IEU provided 30-min energy supply daily to the UP-LVAD. The transcutaneous information transmission system transmitted data bidirectionally between the IEU and the personal computer at the data transmission ratio of 56 kbps without any transmission error. We could obtain survival days of 27 and 28 days supporting cardiac function with the UP-LVAD system. The temperature inside the IEU case was maintained under 45 degrees C, and there was evidence of a burn on the surrounding tissue in autopsies in each experiment. Based on the results, the IEU is promising to be suitable for drive and control of an implantable UP-LVAD.  相似文献   
996.
A novel approach to the treatment of bone tumors using tissue-engineered implants is reported in this study. The number of mesenchymal stem cells (MSCs) obtained from each patient's bone marrow cells was first increased, and the MSCs were forced to differentiate into osteoblasts followed by bone matrix formation on hydroxyapatite (HA) ceramics. The strong osteogenic ability of the implants, as evidenced by high osteoblastic activity, was confirmed. Consequently, the HA surface was covered with the patient's derived cultured osteoblast/bone matrix. The tissue-engineered HA was used to fill the patient's bone cavity after tumor curettage. Immediate healing potential was found by serial plain radiographs and computed tomograhy images, and no adverse reactions were noted in these patients. The results indicate that tissue-engineered osteogenic ceramics might be an alternative to autologous bone grafts.  相似文献   
997.
Autologous mesenchymal stem cells (MSCs) cultured with beta-tricalcium phosphate (beta-TCP) ceramics and with a free vascularized fibula were transplanted into three patients with steroid-induced osteonecrosis of the femoral head. The average follow-up period was 34 months and the average patient age at the time of surgery was 28 years old. Fifteen milliliters of bone marrow was obtained from the patients 4 weeks before surgery, and was used for in vitro proliferation of MSCs. beta-TCP granules were immersed in the MSC suspension and the cells were further cultured for 2 weeks. Cultured MSCs/beta-TCP composite granules were implanted into the cavity that remained after curettage of necrotic bone; and finally, a free vascularized fibula was grafted. All hips showed preoperative collapse and radiographic progression was observed in two hips postoperatively. Osteonecrosis did not progress any further and early bone regeneration was observed. This tissue-engineered approach has potentials for the treatment of osteonecrosis. However, our results suggested that the present procedure could not be used for cases with severe preoperative collapse.  相似文献   
998.

Background

Antenatal magnetic resonance imaging (MRI) is useful for the diagnosis of abdominal wall defects. Its predictive value concerning the possibility of primary closure of the abdominal wall, however, has so far not been reported.

Methods

Between August 2001 and November 2004, antenatal MRI was performed on 9 patients with abdominal wall defects in whom surgical repair was performed immediately after birth. Areas of the abdominal cavity and exteriorized viscera were manually traced from both sagittal and axial MR images, and the data were further transmitted to a Workstation for MRI Volumetry (Advantage Windows 4.1, General Electric Medical Systems, Milwaukee, Wis). We examined the exteriorized ratio (ER), which is calculated by dividing the absolute volume of the abdominal cavity by that of the exteriorized viscera, and evaluated the predictive value by a retrospective comparison with surgical procedure.

Results

In the primary closure group (n = 5), mean values of ER were 0.33 ± 0.31 from axial and 0.45 ± 0.31 from sagittal MR images. In contrast, in the staged closure group (n = 4), mean values of ER were 1.39 ± 0.40 from axial and 1.34 ± 0.42 from sagittal MR images. There was a significant difference (P < .05) between the 2 groups for both sets of images. The ER obtained from antenatal MRI correlated well with surgical procedure.

Conclusions

The ER might be useful for antenatal counseling, planning for delivery, and prediction of the most likely surgical procedure.  相似文献   
999.
Orthotopic bladder substitution is the most desired form of urinary diversion because the patient can restore normal voiding after cystectomy. However, urethral recurrence must be seriously considered and the patients with a risk of urethral recurrence are not indicated. Each method of bladder substitution has merits and demerits. We compared the Mainz method and the Studer method of orthotopic bladder substitution we performed on 8 and 11 patients, respectively since 1992. The Studer orthotopic ileal bladder substitution has given better results with better voiding pattern and less complication rates. We consider the Studer ileal bladder substitution as a good technique to restore normal voiding after cystectomy.  相似文献   
1000.
BACKGROUND: Removal of the primary lesion with a clear operative margin is the standard treatment for gastrointestinal stromal tumor (GIST) of the stomach. However, there are few reports on the operative indications for relatively small GIST. METHODS: Clinicopathologic features and survival data of all 60 patients with GIST of the stomach treated at Keio University Hospital from 1993 to 2004 were analyzed. Laparoscopic wedge resection was used as the primary procedure for tumors between 2 to 5 cm. Tumors larger than 5 cm were resected by laparotomy or laparoscopy-assisted operation. RESULTS: Thirty-five lesions (58.3%) were resected by laparoscopic wedge resection, 3 by laparoscopic operation with a small skin incision and 22 by conventional open procedures. The mean size of the tumors was 42.5 mm, with a range of 18 to 150 mm and a median value of 35.5 mm. All operative margins were clear, but 1 patient had liver metastases at the time of resection of the primary lesion. The median follow-up period was 53 months and the 5-year disease-free survival rate (DFS) was 96.1%. No local recurrence or distant metastasis was encountered in patients with tumors smaller than 4 cm. A statistically significant correlation was observed between tumor size and mitotic count in this cohort (P = .010). Tumors from the intermediate- (n = 14) and high-risk (n = 10) groups as classified by the Risk Assessment Classification showed significantly worse DFS than the low-risk and very low risk group (n = 35) (89.9% vs 100% in 5-year DFS, P = .045). Even among tumors smaller than 3 cm, 2 of 14 cases (14.3%) were classified into the intermediate-risk group. CONCLUSIONS: Although a prospective randomized trial remains to be performed, this study provides additional evidence suggesting that the early removal of GIST, at 5 cm or less in size, provides better DFS than later removal of the tumor at a larger size.  相似文献   
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