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101.
Heparin cofactor II is postulated to be an extravascular thrombin inhibitor that is physiologically stimulated by dermatan sulfate. However, the role of heparin cofactor II has not yet been clearly demonstrated in vivo. In this study, we estimated the antithrombotic effect of heparin cofactor II administered exogenously in a rat model of thrombosis. Thrombus was induced in the rat femoral artery by endothelial damage due to the photochemical reaction between systemically injected rose bengal and transillumination with green light. Pretreatment with heparin cofactor II significantly prolonged the time required to occlude the femoral artery (occlusion time) in a dose-dependent manner. At an effective dose in this thrombosis model, heparin cofactor II did not prolong the activated partial thromboplastin time and the prothrombin time in normal rats. Argatroban, a selective synthetic thrombin inhibitor, significantly prolonged the occlusion time. However, argatroban also prolonged the activated partial thromboplastin time and prothrombin time at an effective dose. These results suggest that the administration of heparin cofactor II in vivo effectively inhibited thrombus formation on the vessel walls whose endothelium is damaged without a prolongation of the coagulation time while heparin cofactor II may also inhibit the thrombin activity in the subendothelial tissue in vivo.  相似文献   
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PURPOSE: Cladribine (2-CdA) is a purine analogue that exhibits activity against a variety of hematological malignancies and has a potent immunosuppressive effect. We therefore performed a pilot study to evaluate the feasibility of a novel 2-CdA-based reduced-intensity stem cell transplantation (RIST) regimen. EXPERIMENTAL DESIGN: A total of 16 scheduled patients with hematological malignancies were enrolled for comparison of their data with conventional stem cell transplantation (n = 19). The regimen for RIST consisted of 2-CdA (0.11 mg/kg/day for 6 days), busulfan (4 mg/kg/day for 2 days), and rabbit antithymocyte globulin (2.5 mg/kg/day for 4, 2, or 0 days). The underlying diseases included acute myelogenous leukemia (n = 6), chronic myelogenous leukemia (n = 2), myelodysplastic syndrome (n = 6), and non-Hodgkin's lymphoma (n = 2). RESULTS: After RIST, four patients died before day 100 as a result of acute graft-versus-host disease (n = 1), bacteremia (n = 1), disseminated candidasis (n = 1) and congestive heart failure (n = 1). Another patient died of cerebral infarction on day 140. Thus, acute-phase regimen-related toxicities >grade III were observed in only one patient. Engraftment and complete donor chimerism were achieved by day 28 in 14 evaluable patients, and 6 of them (43%) experienced grade II-IV acute graft-versus-host disease. With a median follow-up of 328 days (range, 231-633 days), the actuarial 1-year overall and disease-free survival rates were 69% and 50%, respectively. Notably, among seven high-risk patients (five patients had been in complete remission two or more times and two not in complete remission with refractory disease at transplant), only two patients developed leukemia relapse after RIST. Although the recovery of CD4+ cells was significantly slower (P = 0.02) in RIST than in conventional stem cell transplantation, the incidence of clinically documented infections was not significantly different between the two groups. CONCLUSION: The results suggest that this novel regimen containing 2-CdA is well tolerated and induces early complete donor chimerism. The unexpected durable remission achieved in patients with advanced disease at transplant suggests the presence of an acceptable antileukemia/lymphoma effect, which would warrant a further clinical trial.  相似文献   
104.
We experienced a rare case of endotracheal metastasis derived from squamous cell lung cancer. The patient was 56 year-old male whose primary lung cancer of the left upper lobe was completely resected. Pathological diagnosis indicated stage IIB and he underwent two cycles of chemotherapy with CDDP + VDS. He had been asymptomatic thereafter, however, two years postoperative chest CT revealed a nodular lesion of the anterior carinal wall. Bronchofiberoptic examination showed same as CT finding and its brushing cytology confirmed squamous cell carcinoma. WE successfully resected his endotracheal metastatic lesion and reconstructed by direct sutures assisted by PCPS (Percutaneous Cardiopulmonary Support System). His postoperative course was uneventful. Majority of the reported cases of endotracheal metastases were treated conservatively as radiation, laser and/or chemotherapy. We conclude that PCPS is useful device for surgical management for selected cases.  相似文献   
105.
We report a case of multiple endocrine neoplasia type 1 who had repeated hypoglycemic episodes and had previously been diagnosed with bipolar manic-depressive disorder. The patient had a positive family history of multiple endocrine neoplasia type 1 and had multiple pancreatic endocrine tumors, hyperparathyroidism and possibly a pituitary tumor. The pancreatic tumors were resected by subtotal pancreatectomy and examined by histochemical staining and gene analysis. The tumor cells were positive for immunoreactive insulin and glucagon. A microsatellite polymorphism analysis revealed loss of heterozygosity on 11q13 in the tumors. By polymerase chain reaction-based nucleotide sequencing, we identified a germline mutation 483del2 of the MEN1 gene in the normal pancreatic tissue of the patient. This mutation causes a shift of the reading frame of menin mRNA at codon 125. It seems that the wild type allele of the MEN1 gene had been lost in the tumor cells whereas the mutant allele remained intact. This is the first identified MEN1 gene mutation in Japanese families and is different from all MEN1 gene mutations reported previously.   相似文献   
106.
A considerable number of gastric cancers derive from stomach mucosa where chronic atrophic gastritis is severe and extensive. Based on the fact that the serum pepsinogen levels provide a precise measure of the extent of chronic atrophic gastritis, we have devised a mass screening method involving serum pepsinogen measurement to identify subjects at high risk of gastric cancer. In 1991, we screened 4,647 workers (male: 4,113, female: 534, mean age: 49.0 years) at a Japanese company using this method. Out of 875 subjects (18.8%) with a serum pepsinogen I level of less than 50 μg/liter and a pepsinogen I/II ratio of less than 3.0, 676 subjects (14.5%) were selected for further investigation by endoscopy. This led to the detection of four subjects (0.086%) with gastric cancer (three in an early stage) and four subjects with adenoma. The cancer detection rate of this new screening method was comparable, and in some respects superior, to that of the traditional barium X-ray screening. Since the incidence of test-positive subjects was as low as 10% amongst subjects aged less than 40, this screening method appears to be especially useful for screening of younger generations. The new method is less expensive than the traditional barium X-ray and subjects experience little discomfort. Further, many serum samples can be quickly measured simultaneously. The results of this study have indicated that serum pepsinogen screening provides a valuable method for detecting gastric cancers.  相似文献   
107.
In vitro studies were initiated to study the antitumour effect of protein-doxorubicin (DXR) conjugate on the growth of the multidrug resistant rat ascites hepatoma cell line, AH66DR. The 50% inhibitory concentration (IC50) for DXR in AH66DR cell line was 16 mumol l-1 (AH66 parental cell line, AH66P, IC50 was 0.08 mumol l-1). Treatment of AH66P and AH66DR cells with various concentrations of DXR or conjugates at equivalent concentrations of DXR was performed. The two types of conjugates used were bovine serum albumin (BSA)-DXR conjugate and immunoglobulin G (IgG)-DXR conjugate. Both of these conjugates showed potent dose-dependent inhibition of cell growth against AH66DR cells as compared with the cells treated with DXR or other controls. The IC50 for BSA-DXR and IgG-DXR conjugates in AH66DR cell line was 0.05 (equivalent DXR) mumol l-1 and 0.07 (equivalent DXR) mumol l-1, respectively. These values were similar to that of the AH66P treated with DXR. Cellular uptake and accumulation of DXR or BSA-DXR conjugate was also quantitated in both cell lines. The cellular concentration of DXR in AH66DR cells was 2-fold lower than that of AH66P cells throughout the experiment. In contrast, by the treatment of AH66DR cells with BSA-DXR conjugate, the intracellular drug concentration increased as a function of time up to 24 h (639.1 +/- 41.8, equivalent DXR, ng 10(-5) cells) and reached the same drug level as AH66P cells treated with DXR (617.9 +/- 17.3 ng-5 cells). Ammonium chloride treatment inhibited the effects of the conjugates but did not inhibit the free drugs. Intracellular DXR was effluxed rapidly from AH66DR cells, but BSA-DXR conjugate remained in the cells at relatively high concentration for a long time. These results indicate that by chemically modifying DXR, such as by conjugation of the drug with proteins, it may be possible to overcome multidrug resistance.  相似文献   
108.
Plasma renin activity (PRA) and plasma aldosterone concentration (PAC) were measured in 156 healthy infants and children under basal conditions of normal diet and recumbency. PRA and PAC were also evaluated during and after stimulation of the renin-angiotension-aldosterone system by postural change. Basal values of PRA significantly declined with increasing age. Postural change by standing up resulted in an increase of PRA and PAC in all age groups. The increment of PRA but not of PAC was greater in older than in younger children. Neither the basal nor the stimulated levels of PRA and PAC were influenced by sex, body weight, body surface area, serum sodium, serum potassium, creatinine, and 24-h urine secretion of sodium and potassium. Both PRA and PAC returned to the basal levels within 60 min after resuming recumbent posture.  相似文献   
109.
110.
BACKGROUND: KAI1/CD82, a tumor metastasis suppressor gene, is correlated inversely with the progression and invasion of several tumors. It also has been reported that the KAI1 gene is related to the tumor suppressor gene p53. This study was performed to clarify the correlation between KAI1/CD82 expression and clinicopathologic characteristics and p53 expression in patients with esophageal squamous cell carcinoma (ESCC). The authors also investigated mutation of the KAI1 gene coding region to determine whether this may reduce KAI1 expression in ESCC. METHODS: Using immunohistochemistry with anti-KAI1 polyclonal antibody and monoclonal antibody against p53, KAI1/CD82 and p53 expression were detected in 55 patients with ESCC who had undergone surgery. The authors examined the KAI1 gene mutation in 22 patients with ESCC by polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) analysis and DNA sequencing. RESULTS: KAI1/CD82 expression was positive in 36 of 55 patients (65.5%). There was a significant inverse correlation between KAI1/CD82 expression and regional lymph node metastasis (P = 0.0045), distant metastasis (P = 0.0092), the number of lymph node metastases (P = 0.0019), and pathologic stage (P = 0.0046). The survival rates of KAI1/CD82 negative patients were poorer than those of positive patients (P = 0. 024). The correlation between KAI1 positive and p53 positive tumors was not statistically significant. None of the 22 patients with ESCC showed mutation of the KAI1 gene by PCR-SSCP. In one patient, there was polymorphism in the SSCP assay and DNA sequencing. CONCLUSIONS: The authors demonstrated immunohistochemically that the expression of KAI1 protein appeared to be correlated with lymph node metastasis. Mutation does not seem to be a mechanism for dysregulation of the KAI1 protein in ESCC.  相似文献   
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