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91.
A lymphoepithelial cyst (LEC) is an extremely rare benign lesion of the pancreas. During a medical check-up, a 77-year-old man without any symptoms was found to have a cyst in the body of the pancreas. His serum carbohydrate antigen 19-9 level was slightly elevated. Computed tomography showed a multilocular, low-attenuating cyst on the superior surface of the pancreatic body. Thus, we performed distal pancreatectomy with splenectomy. Histological examination revealed that the cyst wall was lined with squamous epithelium and surrounded by abundant mature lymphoid tissue. Keratinous substances were present in the cyst. An LEC of the pancreas is associated with a good prognosis and, although unusual, it should be considered in the differential diagnosis of pancreatic cystic lesions. Minimal resection of the cyst should be performed whenever possible, and extensive surgery avoided. For patients with a high surgical risk, fine-needle aspiration biopsy may be considered.  相似文献   
92.
Abstract:  A 38-yr-old man with chronic renal failure received a second kidney transplantation from a cadaveric donor. Complement-dependent cytotoxicity cross-match (CDC) was negative against T cells, but positive with the B-cell warm test. Human leukocyte antigen (HLA)-typing showed a one haplo-identical match. The blood type was compatible. He was treated with tacrolimus, mycophenolate mofetil (MMF), methylpredonisolone (MP), and basiliximab as immunosuppressive therapy. A clinical episode graft biopsy and Flow-PRA on post-operative day (POD) 19 showed anti-HLA antibody-mediated acute rejection (AHR). The patient was treated with plasmapheresis (PP). Renal biopsy performed on POD 65 because of re-rise of serum creatinine level showed worsening of renal injury. The patient was treated with rituximab (100 mg/body) with PP and MP pulse therapy, followed by tacrolimus and MMF. Graft function thereafter improved. A renal allograft biopsy specimen on POD 300 and Flow-PRA showed the remission of AHR within one-yr after transplantation.  相似文献   
93.
A 72-year-old man was admitted to another hospital because of general fatigue and dyspnea secondary to renal insufficiency. Abdominal computed tomography (CT) and magnetic resonance imaging showed left atrophic kidney, right hydronephrosis, and an intra-pelvic mass of soft-tissue density located anterior to the sacrum, involving the right ureter at the level between the 5th lumber vertebra and the sacrum. He was referred to our hospital after percutaneous nephrostomy was constructed into right kidney. CT-guided needle biopsy revealed the idiopathic retroperitoneal fibrosis, leading us to give him steroid therapy. Three weeks later, radiographic findings showed a remarkable reduction of the mass and the improvement of the right ureteral stricture.  相似文献   
94.
It has been reported that in patients undergoing posterolateral lumbar fusion (PLF), the fusion status is not related to the short-term operative results. To determine whether the fusion status influences the long-term operative results of PLF, we retrospectively examined the surgical outcomes of uninstrumented PLF for a minimum of 8 years (average, 9.5 years), by comparing cases exhibiting union with those exhibiting nonunion. Uninstrumented PLF was performed for the treatment of lumbar canal stenosis (LCS) with degenerative spondylolisthesis. Since nine patients were lost to final follow-up, the study included 42 patients, and the follow-up rate was 82.4%. The mean age of the patients was 64.1 years (range 46–77 years). Eight patients exhibited fusion at the L3–4 level and 34 patients, at the L4–5 level. The fusion status was assessed using plain radiographs. The clinical outcomes were evaluated using the Japanese Orthopaedic Association (JOA) scores. Nonunion was noted in 26% (11/42) of the patients. There were no statistically significant differences between the groups exhibiting union and nonunion with respect to age, sex, preoperative JOA score, or preoperative lumbar instability. The union group achieved better operative results than the nonunion group at the 5-year and final follow-up (P = 0.006 and 0.008, respectively) although there was no significant difference in the percent recovery at 1 and 3-year follow-up (P = 0.515 and 0.506, respectively). A stepwise regression analysis revealed that the best combination of predictors for percent recovery at the time of final follow-up included the fusion status and the presence of comorbid disease. The results indicate that the fusion status following PLF is a critical factor influencing the long-term but not short-term operative results in the treatment of LCS with degenerative spondylolisthesis.  相似文献   
95.
96.
Tanaka M  Mori H  Kayasuga R  Ochi Y  Kawada N  Yamada H  Kishikawa K 《BONE》2008,43(5):894-900
The present study examined the effect of the highly potent nitrogen-containing bisphosphonate, minodronic acid (ONO-5920/YM529), on bone mineral density (BMD), bone turnover, bone histomorphometry and bone strength in ovariectomized (OVX) rats. Female F344/DuCrj rats, aged 14 weeks, were OVX or sham operated. After 3 months, the OVX rats showed an increase in bone turnover, and a decrease in bone mass and bone strength. Minodronic acid was administered orally once a day for 12 months at doses of 0, 0.006, 0.03 and 0.15 mg/kg from 3 months after OVX. Minodronic acid dose-dependently inhibited the decrease in BMD of lumbar vertebrae and femur. In the femur, treatment with 0.15 mg/kg minodronic acid increased the BMD of distal and mid sites to sham levels. Minodronic acid dose-dependently suppressed OVX-induced increase in urinary deoxypyridinoline, a bone resorption marker, after a month of treatment and these effects were maintained for 12 months of treatment. Minodronic acid also decreased serum osteocalcin, a bone formation marker. In bone histomorphometric analysis after 12 months of treatment, OVX rats showed an increase in bone resorption (Oc.S/BS and N.Oc/BS) and bone formation (MS/BS and BFR/BV) at lumbar vertebral bodies. Minodronic acid suppressed the OVX-induced increase in bone turnover at tissue level. Trabecular bone volume, trabecular thickness and trabecular number of lumbar vertebral bodies were decreased after OVX. Minodronic acid increased these structural indices, indicating that it prevented the deterioration in trabecular architecture. In a mechanical test at 12 months of treatment, ultimate load of lumbar vertebral bodies and mid femur in the OVX-control group was decreased compared to the sham group. Minodronic acid prevented the reduction in bone strength at both sites. In particular, in the mid femur, treatment with 0.03 and 0.15 mg/kg minodronic acid increased bone strength to sham levels or greater. In conclusion, minodronic acid suppressed increased bone turnover, plus prevented the decrease in BMD, deterioration of bone microarchitecture and reduction in bone strength in OVX rats with established osteopenia. These results suggest that minodronic acid may be clinically useful for treatment of osteoporosis.  相似文献   
97.
A single-dose ofantimicrobial prophylaxis (AMP) was administered parenterally for prevention of perioperative infection in a total of 206 urologic surgeries including 114 endoscopic-instrumental, 92 clean, and 20 clean-contaminated procedures between January and December, 2007, and surgical site infections (SSI), urinary tract infections (UTI), and remote infections (RI) were prospectively surveyed. The definition of a single-dose of AMP allowed the administration of a second dose of an antimicrobial during a surgical procedure that exceeded 3 hours but not parenteral or oral administration at the end of the procedure, in the recovery room, or at a later time over a period of more than 24 hours. UTI was observed in 3 cases (2.7%) after endoscopic-instrumental procedures and in 1 case (5%) after clean-contaminated procedures while no case was associated with UTI in clean procedures. SSI was seen in 1 case each after clean procedures (1.1%) and after clean-contaminated procedures (5%), and RI was seen in 2 cases (2.2%) after clean procedures. A single-dose regimen of AMP was effective for prevention ofperioperative infections including SSI, UTI, and RI in endoscopic-instrumental, clean, and clean-contaminated surgical procedures in urology.  相似文献   
98.
Adipose tissue-derived stem cells (ASCs) are expected to have clinical applications as well as other stem cells, because ASCs can be obtained safely from adult donors and used in autologous therapies without concern about rejection and the need for immunosuppression. However, the use of gene transfer with Sendai virus (SeV) vectors, which can efficiently introduce foreign genes without toxicity into several cells, with ASCs has not yet been investigated. This study documents on the use of SeV vectors for gene transfer to ASCs. The dose-dependent GFP expression of ASCs transfected with SeV vectors after 48 h of culture at 37 degrees C was first evaluated. Next, the cellular toxicity of ASCs transfected with SeV vectors was verified. In addition, SeV vectors were compared with adenovirus (AdV) vectors. Finally, the time-dependent GFP expression of ASCs transfected with SeV vectors was evaluated. The results showed that transfection of ASCs with SeV vectors results in more efficient expression of transgene (GFP expression) in the ASCs than with AdV vectors after 48 h of culture at 37 degrees C. Moreover, while the transfection of ASCs with AdV vectors at high MOIs was cytotoxic (a lot of transfected cells died) that of ASCs with SeV vectors at high MOIs was not necessarily cytotoxic. In addition, the preservation of multilineage ASCs transfected with SeV was observed. In conclusion, this is the first report describing the successful use of SeV-mediated gene transfer in ASCs, and the results indicate that SeV may thus provide advantages with respect to safety issues in gene therapy.  相似文献   
99.
BACKGROUND: Recently, tissue-engineered chondrocyte transplantation has been tried to treat full-thickness cartilage defects. We developed an injectable type II collagen gel scaffold by chemically reacting type II collagen with polyethylene glycol crosslinker. This type II collagen was prepared from the nasal septa of cattle. In the present study, chondrocytes embedded in type II collagen gel were injected into rabbit full-thickness cartilage defects without a periosteal graft, and the feasibility for clinical application of the gel was evaluated. METHODS: Chondrocytes were isolated from 1-kg New Zealand white rabbits. A full-thickness articular cartilage defect (5 mm diameter, 4 mm depth) was created on the patellar groove of the femur of 16 male 3-kg New Zealand white rabbits. A type II collagen solution of mixed chondrocytes at a density of 1 x 10(7) cells/ml was injected and transplanted into the defect in the right knee. The controls were the defect only in the left knee. At 4, 8, 12, and 24 weeks after operation, four cases from each group were evaluated macroscopically and histologically. RESULTS: After injection into the cartilage defect, the gel bonded to the adjacent cartilage and bone within several minutes. Macroscopic examination revealed that the surface of the transplanted area was smooth and exhibited similar coloration and good integration with the surrounding cartilage at 12 and 24 weeks after transplantation. Histological examination at 8 weeks revealed favorable hyaline cartilage regeneration with good chondrocyte morphology. At 12 and 24 weeks, reparative cartilage remained rich in type II collagen. According to O'Driscoll histological scores, significant differences between the transplanted and control groups were apparent at 12 and 24 weeks. Immunohistochemical staining indicated sufficient type II collagen synthesis in regenerated cartilage 8 weeks after transplantation, and it was maintained until 24 weeks. CONCLUSIONS: These results indicate that type II collagen gel is suitable for injection into cartilage defects without any covering of a graft and offers a useful scaffold during chondrocyte transplantation.  相似文献   
100.
The clinicopathological characteristics relevant to prognosis after surgical treatment of intrahepatic cholangiocarcinoma (ICC) remain unclear. In this study, the clinicopathological features of 19 patients with mass-forming ICC, the most common form of the disease, were reviewed to analyze prognostic determinants. Two or more segmentectomies of the liver with systematic lymphadenectomy were performed in 18 patients. Resection of the extrahepatic bile duct was performed in 14 patients, and reconstruction of the portal vein was accomplished in 5 patients. Stage IVA or IVB tumors were seen in 13 patients, and lymph node (LN) metastasis was present in 14 patients. The estimated 5-year survival rate after surgery for mass-forming ICC was 28%, with median survival time of 18 months. In univariate analysis, five variables were determined to be significantly correlated with poor survival of patients with mass-forming ICC after surgery. These variables include mass-forming ICC with periductal infiltration, perineural invasion, portal vein invasion, presence of intrahepatic metastasis, and two or more LN metastases. Survival rates of 5 patients without LN metastasis and 6 patients with a single LN metastasis were 80% and 33% at 5 years, respectively, while 8 patients with two or more LN metastasis failed to survive beyond 2 years. Multivariate analysis revealed the presence of intrahepatic metastasis to be an independent prognostic factor of poor survival. Hepatectomy with resection of the extrahepatic bile duct and systematic lymphadenectomy yields a good chance for prolonged survival for patients with mass-forming ICC when the lesion is singular and LN metastasis is limited to a regional LN. Because the presence of intrahepatic metastasis was closely related to a poor prognosis in patients with mass-forming ICC, efficacious chemotherapy would be needed to control development of the lesion.  相似文献   
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