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621.
AIM: To investigate the expression of microRNA-141 (miR-141) in human hepatocellular carcinoma (HCC) cell line SMMC-7721 and normal hepatocyte line HL-7702, and to analyze the effect of abnormal expression of miR-141 on the malignant biological behaviors of human hepatocarcinoma cells. METHODS: The RNA from SMMC-7721 cells and HL-7702 cells was extracted. SYBR Green real-time PCR was performed to detect the expression of miR-141. Synthetic miR-141 mimic and its negative control were transfected into the SMMC-7721 cells, and miR-141 inhibitor and its negative control were transfected into the HL-7702 cells by the method of Lipofectamine. After transfection, MTS assay and BrdU-ELISA were employed to evaluate the effect of miR-141 on the cell proliferation. Flow cytometry was used to detect cell cycle and apoptosis. The changes of migration ability were investigated by Transwell invasion assay. RESULTS: The expression of miR-141 in the SMMC-7721 cells was significantly lower than that in the HL-7702 cells (P < 0.05). Compared with blank group, Lipofectamine group and negative control group, the proliferation of the SMMC-7721 cells transfected with 25 nmol/L miR-141 mimic was significantly inhibited in a time-dependent manner (P < 0.05). The percentages of G1 phase cells and early apoptotic rate were significantly increased when miR-141 was up-regulated, but the migration ability was inhibited (P < 0.05). Compared with blank group, Lipofectamine group and negative control group, the proliferation of HL-7702 cells transfected with 50 nmol/L miR-141 inhibitor was significantly increased in a time-dependent manner (P < 0.05). When miR-141 was down-regulated, the percentages of G1 phase cells and early apoptotic rate were significantly decreased, but the migration ability was enhanced (P < 0.05). CONCLUSION: miR-141 is down-regulated in human hepatocarcinoma cell line. Up-regulation of miR-141 will not only inhibit cell proliferation and migration ability, but also affect the cell cycle and apoptosis of SMMC-7721 cells. miR-141 may function as a tumor suppressor gene during HCC development.  相似文献   
622.
目的探讨川芎嗪(TMP)对人鼻咽癌顺铂(DDP)耐药细胞系(CNE2/DDP)多药耐药性的逆转作用。方法 TMP处理CNE2/DDP细胞后,分别用MTT法、流式细胞术、RT-PCR检测其对DDP耐药性的逆转作用、细胞凋亡和bcl-2mRNA表达的影响。结果 50、100mg/LTMP处理后,CNE2/DDP细胞对DDP耐药性的相对逆转率分别为57.50%、85.72%,差异有统计学意义(P〈0.01)。与对照组比较,50mg/LTMP处理可使CNE2/DDP细胞凋亡率明显增高(P〈0.01),而bcl-2mRNA表达明显降低(P〈0.05)。结论 TMP可部分逆转CNE2/DDP细胞对DDP的耐药性。TMP可增强DDP对CNE2/DDP细胞的促凋亡作用,下调bcl-2mRNA表达。  相似文献   
623.
Twenty‐nine dogs were treated with linac‐based stereotactic radiation therapy (SRT) for non‐lymphomatous nasal tumours. Only dogs with a follow‐up time >365 days were included in this retrospective analysis. No dogs had evidence of distant metastasis at diagnosis. Treatment was planned and a total of 30 Gy in 3 daily 10 Gy fractions was delivered using intensity‐modulation, cone‐beam CT‐based image guidance and a robotic treatment couch. Clinical signs improved in all cases. Nineteen dogs had CT scans 3‐4 months post‐SRT and all had partial or complete tumour response. Minimal acute toxicities were detected. Clinically significant late toxicities included oronasal or nasocutaneous fistulas (N = 3) and biopsy‐confirmed fungal rhinitis with no evidence of tumour progression (N = 2). The median progression‐free survival (PFS) was 354 days, with 49% and 39% progression‐free at 1 and 2 years post‐SRT, respectively. The median survival time (ST) was 586 days, with 69% and 22% alive 1 and 2 years post‐SRT, respectively. Neither the clinical parameters evaluated (modified Adams’ stage, histopathology, presence of intracranial extension of the tumour) nor dosimetric data were predictive for PFS or ST. This SRT protocol appears to be well tolerated, and PFI and ST are comparable or superior to those reported in other definitive‐intent radiotherapy protocols.  相似文献   
624.
目的:探讨端粒酶在原发性肝细胞癌(HCC)患者肝组织中的表达及临床意义。方法:用TRAP—ELISA法检测45例原发性肝细胞癌和26例癌旁组织以及7例正常肝组织的端粒酶活性。结果:45例原发性肝细胞癌组织中有38例显示端粒酶活性,其阳性率为84.4%,而26例癌旁组织只有2例具端粒酶活性,阳性率只为7.6%;7例正常肝组织端粒酶表达均为阴性;结果还显示肝癌组织端粒酶的表达与肿瘤病理分化程度无关。结论:端粒酶在绝大多数原发性肝细胞癌中表达,其活性可能在HCC的发生和发展中起重要作用,有希望成为诊断HCC的肿瘤标志物。  相似文献   
625.
AIM:To study the effect of Aurora protein kinase inhibitor VX-680 on homogeneous adhesion and migration ability in human hepatocellular carcinoma cell line HepG2. METHODS:The HepG2 cell were divided into experimental group and control group, respectively. VX-680 was used in experimental groups at 3 concentrations (3.125 μmol/L group, 6.25 μmol/L group and 12.5 μmol/L group). DMSO was used in the control group. The effects of VX-680 at different concentrations on the adhesion ability of human hepatocellular carcinoma HepG2 cells were observed by cell slow aggregation test and separation experiment. The effects of VX-680 at different concentrations on the migration ability of HepG2 cells was detected by wound healing assay. The expression of E-cadherin in HepG2 cells was detected by Western blot. RESULTS:The results of the slow aggregation test showed that compared with the control group, the number of cell clumps formed in experimental groups was significantly decreased (P<0.01). The results of separation experiment showed that the ratio of NTC/NTE gradually decreased with the increased concentration of VX-680. The results of wound healing assay showed that as the concentration of VX-680 increased, the cell scratch healing ability gradually weakened compared with control group. The results of Western blot showed that the protein expression of E-cadherin in the HepG2 cells increased with the increased concentration of VX-680 (P<0.05). CONCLUSION:VX-680 increases the homogeneous adhesion and inhibits the migration of HepG2 cells.  相似文献   
626.
A 7-year-old, intact, anestrous, female Doberman pinscher was presented with anorexia and hindlimb swelling of three days duration. Renal failure was documented. Survey radiographs revealed patchy alveolar consolidation and bilateral renomegaly with increased retroperitoneal and sublumbar soft tissue opacification. Renal ultrasonography showed bilateral hydronephrosis with ectatic ureters. A retroperitoneal carcinoma was identified via fine needle aspiration. Percutaneous nephropyelocentesis and antegrade nephrography further delineated the hydronephrosis and ureteral obstruction.  相似文献   
627.
We compared clinical characteristics and outcomes for dogs with various digital tumors. Medical records and histology specimens of affected dogs from 9 veterinary institutions were reviewed. Risk factors examined included age, weight, sex, tumor site (hindlimb or forelimb), local tumor (T) stage, metastases, tumor type, and treatment modality. The Kaplan-Meier product limit method was used to determine the effect of postulated risk factors on local disease-free interval (LDFI), metastasis-free interval (MFI), and survival time (ST). Outcomes were thought to differ significantly between groups when P < or = .003. Sixty-four dogs were included. Squamous cell carcinoma (SCC) accounted for 33 (51.6%) of the tumors. Three dogs presented with or developed multiple digital SCC. Other diagnoses included malignant melanoma (MM) (n = 10; 15.6%), osteosarcoma (OSA) (n = 4; 6.3%), hemangiopericytoma (n = 3; 4.7%), benign soft tissue tumors (n = 5; 7.8%), and malignant soft tissue tumors (n = 9; 14%). Fourteen dogs with malignancies had black hair coats, including 5 of the 10 dogs with MM. Surgery was the most common treatment and, regardless of the procedure, had a positive impact on survival. None of the patient variables assessed, including age, sex, tumor type, site, and stage, had a significant impact on ST. Both LDFI and MFI were negatively affected by higher T stage, but not by type of malignancy. Although metastasis at diagnosis correlated with a shorter LDFI, it did not have a significant impact on ST. On the basis of these findings, early surgical intervention is advised for the treatment of dogs with digital tumors, regardless of tumor type or the presence of metastatic disease.  相似文献   
628.
A 15-year-old female collared peccary (Tayassu tajacu) was presented for ophthalmic examination following sudden onset of blindness. Bilateral retinal detachment was diagnosed, neoplasia suspected, and euthanasia performed. Widespread tumor dissemination was apparent at autopsy, and transitional cell carcinoma was diagnosed histologically. The tumor was identified as arising from the ovary. Epidemiologic features of this case are discussed.  相似文献   
629.
Medical records and biopsy specimens were retrospectively reviewed from 25 dogs diagnosed with unresectable urinary bladder carcinoma and treated with chemotherapy. Our intention was to identify clinical, histologic, and immunohistochemical indicators of prognosis. Immunohistochemical stains for P-glycoprotein, glutathione-S-transferase pi, and factor VIII-related antigen were applied to archived tissue. There were more spayed female dogs than castrated male dogs (76% versus 24%). Transitional cell carcinoma was the most common tumor (88%, n = 22), followed by undifferentiated carcinoma (8%, n = 2) and squamous cell carcinoma (4%, n = 1). Overall median survival was 251 days. Histologic diagnosis and immunohistochemical characteristics did not correlate with prognosis. Spayed females survived significantly longer than castrated males (358 days versus 145 days, P = .042). Dogs that received either doxorubicin or mitoxantrone in addition to a platinum-based chemotherapeutic (either cisplatin or carboplatin) lived significantly longer than those that received only a platinum compound (358 days versus 132 days, P = .042).  相似文献   
630.
The records of 33 dogs treated with radiation therapy for nontonsillar oral squamous cell carcinoma (SCC) were reviewed to determine which, if any, prognostic factors affected local tumor recurrence and survival. Information was collected on nine factors: age, sex, anatomic subsite, intraoral location, bone involvement, radiation dose, portal size, and tumor recurrence. Product limit survival estimates indicated than only anatomic subsite was significantly related to disease-free interval. Mean disease-free interval was 12.0, 3.4, and 1.8 months for maxilla, mandible, and soft tissue subsites, respectively. Four factors were significantly associated with survival. The intraoral location (listed in descending survival time: rostral > caudal > rostral and caudal), tumor recurrence (no > yes), relative portal size (less than 100 cm2/m2 > greater than or equal to 100 cm2/m2), and age at diagnosis (less than or equal to 6 years > greater than 6 years) were of prognostic importance. Based on these data, a prospective randomized clinical trial for the treatment of nontonsillar oral SCC would be appropriate.  相似文献   
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