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71.
Sentinel lymph node (SLN) biopsy is increasingly being used as an accurate and less morbid surrogate for axillary dissection. However, a standardized technique in the biopsy of SLNs is not used. Some authors propose subdermal injection to be as accurate as peritumoral intraparenchymal injection (IPI). Our objective is to determine whether the SLNs identified by subdermal injection truly represent SLNs and match those found with IPI. Specific end points of the study were 1) successful localization of the SLN by the IPI of isosulfan blue or the radiocolloid intradermal injection, 2) successful uptake of radiocolloid and isosulfan blue on individual SLN, and 3) determination of the frequency with which the radiocolloid injection detected the "gold standard" blue SLN. SLNs were found in 71 of 73 cases (success rate = 97%). Blue SLNs were identified in 64 patients (88%). SLNs in 61 patients (84%) were radioactive. A total of 112 SLNs were identified in 71 patients (1.6 nodes/patient). Seventy-six of 87 SLNs found with IPI were also radioactive (concordance of 87%). All SLNs harboring metastatic cancer (16 patients) were found by both techniques, being both blue and radioactive. Our results support the concept of shared lymphatic pathways in the breast with a high degree of communication between the subdermal lymphatics and the intraparenchymal lymphatics. The success in identification of the SLN is made simpler and improved by the addition of subdermal radiocolloid injection.  相似文献   
72.
Fluid transport parameters in intracranial tumours influence the delivery of therapeutic agents and the resolution of peritumoral oedema. The tumour and cortex interstitial fluid pressure (IFP) and the cerebrospinal fluid pressure (CSFP) were measured during the growth of brain and pial surface tumours [R3230AC mammary adenocarcinoma (R3230AC) and F98 glioma (F98)] in rats. Intratumoral and intracranial pressures were also measured in rodents and patients treated with dexamethasone, mannitol and furosemide (DMF), and hypocapnia. The results show that (1) for the R3230AC on the pial surface, IFP increased with tumour volume and CSFP increased exponentially for tumours occupying a brain volume of 5% or greater; (2) in F98 with volumes of approximately 10 mm3, IFP decreased from the tumour to the cortex, whereas for tumour volumes > 16 mm3 IFP equilibrates between F98 and the cortex; (3) DMF treatment reduced the IFP of intraparenchymal tumours significantly and induced a pressure gradient from the tumour to the cortex; and (4) in 11 patients with intracranial tumours, the mean IFP was 2.0 +/- 2.5 mmHg. In conclusion, the IFP gradient between intraparenchymal tumours and the cortex decreases with tumour growth, and treatment with DMF can increase the pressure difference between the tumour and surrounding brain. The results also suggest that antioedema therapy in patients with brain tumours is responsible in part for the low tumour IFP.  相似文献   
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BACKGROUND: This study tested the effectiveness of a nutrient-rich preservation solution in a small animal model of orthotopic whole small bowel transplantation. METHODS: Lewis rats received syngeneic total orthotopic small bowel graft after cold storage for 6 h. Donor small bowel was flushed vascularly with University of Wisconsin (UW) solution and flushed luminally with UW solution or an amino acid-rich (AA) solution as follows: Group 1, no luminal flush; Group 2, UW solution; Group 3, AA solution. Biopsies were taken over 14 days posttransplant; energetics, oxidative stress, neutrophil recruitment and histologic injury were assessed. RESULTS: All animals in Groups 1 and 2 failed to survive 12 h posttransplant due to hemorrhagic shock and fluid loss. In contrast, all animals in Group 3 survived the operation; survival after 14 days was 80% (4/5). In Group 3, full recovery of tissue adenylates (ATP and energy charge) to freshly isolated tissue values occurred within 3 days. Oxidative stress as assessed by malondialdehyde (MDA) levels was low in Group 3 throughout 14 d; Groups 1 and 2 exhibited high oxidative stress over the initial 35 min reperfusion (P<0.05). Neutrophil recruitment (myeloperoxidase activity) was significantly reduced in Group 3 tissues, as was histologic injury (P<0.05 compared to Groups 1 and 2). By day 14, Group 3 exhibited complete mucosal restoration. CONCLUSIONS: The data presented in this communication supports the use of an intraluminal preservation solution that is tailored to the metabolic requirements of the small bowel.  相似文献   
75.
Norovirus and foodborne disease, United States, 1991-2000   总被引:2,自引:0,他引:2  
Efforts to prevent foodborne illness target bacterial pathogens, yet noroviruses (NoV) are suspected to be the most common cause of gastroenteritis. New molecular assays allow for better estimation of the role of NoV in foodborne illness. We analyzed 8,271 foodborne outbreaks reported to the Centers for Disease Control and Prevention from 1991 to 2000 and additional data from 6 states. The proportion of NoV-confirmed outbreaks increased from 1% in 1991 to 12% in 2000. However, from 1998 to 2000, 76% of NoV outbreaks were reported by only 11 states. In 2000, an estimated 50% of foodborne outbreaks in 6 states were attributable to NoV. NoV outbreaks were larger than bacterial outbreaks (median persons affected: 25 versus 15), and 10% of affected persons sought medical care; 1% were hospitalized. More widespread use of molecular assays will permit better estimates of the role of NoV illness and help direct efforts to control foodborne illness.  相似文献   
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In the present study, the effects of intra-locus coeruleus injection of a dopamine D(1) receptor agonist (SKF38393) on naloxone-induced withdrawal signs of morphine-dependent rats were examined. Twenty different withdrawal signs were assessed. The total withdrawal score was calculated and used as an index of withdrawal intensity for comparison. The D(1) agonist and antagonist were injected 15 and 30 min prior to expression of naloxone-induced withdrawal signs, respectively. SKF38393 (2 and 4 microg/site) decreased while SCH23390 (a D(1) antagonist) had no effect on the total withdrawal score. On the other hand, SCH23390 (25 ng/site) reversed the SKF38393 effect. It may be concluded that activation of dopamine D(1) receptors in the locus coeruleus attenuates naloxone-induced withdrawal.  相似文献   
78.
Allgrove syndrome is a genetic disorder inherited in an autosomal recessive pattern and characterized by a triad of adrenal insufficiency, achalasia, and alacrima. The gene affected by the mutation in patients with Allgrove syndrome is termed either AAAS or ALADIN (alacrima/achalasia/adrenal insufficiency/neurologic disorder). Adrenal insufficiency in patients with this disorder may develop as late as the third decade of life. We describe a 24-year-old female with Allgrove syndrome, in whom initial testing with 250 microg corticotropin (ACTH) stimulation test performed on 3 occasions produced normal serum cortisol values and results of the 1-microg ACTH stimulation tests performed on 6 occasions were conflicting. Insulin-induced hypoglycemia produced a nadir serum glucose value of 36 mg/dL without adequate serum cortisol stimulation, confirming presence of adrenal insufficiency. Gene sequencing identified 2 mutations in the triple A gene: an IVSC14 + 1 G to A mutation, which has been previously reported, and a novel R155P exon 6 mutation. We conclude that a novel R155P mutation in the ALADIN gene is associated with Allgrove syndrome and that insulin-induced hypoglycemia, rather than ACTH stimulation tests, should be used for accurate diagnosis of adrenal insufficiency in this disorder.  相似文献   
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80.
BACKGROUND: Lichen planus (LP) is classified as a papulosquamous disease. It has been associated with liver disease, particularly hepatitis C virus (HCV) infection, in several studies. Most of these reports, especially the larger series, were conducted in Europe and Japan. OBJECTIVE: We conducted a case-control study in Kerman, Iran to explore the association between LP and HCV. METHODS: The study included 66 patients with LP (as cases; mean age = 39.7 +/- 15.8 years; 31 female, 35 male) and 140 volunteer blood donors (as controls; mean age = 29.5 +/- 8.4 years; 43 females, 97 males). An enzyme-linked immunosorbent assay (ELISA) was used to determine the presence of anti-HCV antibodies in all subjects in both groups. To confirm positive diagnoses, a second generation recombinant immunoblot assay (RIBA II) test was performed. RESULTS: Lichen planus lesions were most frequently located on the trunk and extremities, and the most common clinical type was generalized LP (48.5%). One of the patients with LP (1.5%) and three of the controls (2.1%) were HCV-Ab positive. No significant difference was observed in HCV-Ab positive between the two groups (OR = 0.7; 95% CI = 0.1-6.9). CONCLUSION: The findings indicate that an investigation for HCV infection should not necessarily be performed in all patients with LP. It is recommended that further studies should focus on larger groups in other regions of Iran to determine whether testing for HCV infection is necessary in patients with LP.  相似文献   
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