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201.
202.
The prognosis for patients with pancreatic cancer is extremely poor, as evidenced by the disease's five‐year survival rate of ~5%. New approaches are therefore urgently needed to improve detection, treatment, and monitoring of pancreatic cancer. MRS‐detectable metabolic changes provide useful biomarkers for tumor detection and response‐monitoring in other cancers. The goal of this study was to identify MRS‐detectable biomarkers of pancreatic cancer that could enhance currently available imaging approaches. We used 1H high‐resolution magic angle spinning MRS to probe metabolite levels in pancreatic tissue samples from mouse models and patients. In mice, the levels of lipids dropped significantly in pancreata with lipopolysaccharide‐induced inflammation, in pancreata with pre‐cancerous metaplasia (4 week old p48‐Cre;LSL‐KrasG12D mice), and in pancreata with pancreatic intraepithelial neoplasia, which precedes invasive pancreatic cancer (8 week old p48‐Cre LSL‐KrasG12D mice), to 26 ± 19% (p = 0.03), 19 ± 16% (p = 0.04), and 26 ± 10% (p = 0.05) of controls, respectively. Lactate and taurine remained unchanged in inflammation and in pre‐cancerous metaplasia but increased significantly in pancreatic intraepithelial neoplasia to 266 ± 61% (p = 0.0001) and 999 ± 174% (p < 0.00001) of controls, respectively. Importantly, analysis of patient biopsies was consistent with the mouse findings. Lipids dropped in pancreatitis and in invasive cancer biopsies to 29 ± 15% (p = 0.01) and 26 ± 38% (p = 0.02) of normal tissue. In addition, lactate and taurine levels remained unchanged in inflammation but rose in tumor samples to 244 ± 155% (p = 0.02) and 188 ± 67% (p = 0.02), respectively, compared with normal tissue. Based on these findings, we propose that a drop in lipid levels could serve to inform on pancreatitis and cancer‐associated inflammation, whereas elevated lactate and taurine could serve to identify the presence of pancreatic intraepithelial neoplasia and invasive tumor. Our findings may help enhance current imaging methods to improve early pancreatic cancer detection and monitoring. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
203.
Abstract

Background: Pancreatic cancer is a fatal disease most often diagnosed at an advanced stage. Most patients already suffer from irresectable tumor or distant metastases being most commonly found in the liver or the lung. However, cerebral metastases occur extremely rare.

Methods: We performed a retrospective analysis of our database to identify all patients diagnosed with pancreatic cancer and cerebral metastases who underwent surgical treatment in our department from January 2004 to November 2016.

Results: Only 0.2% (4 of 2492) were diagnosed with cerebral metastases. Two patients had surgical resection of the cerebral metastases. One patient underwent palliative radiation therapy and the fourth patient received only palliative therapy. Mean interval between initial diagnosis and development of brain metastases was 8.5 months (range 1–20). Mean survival period after diagnosis of brain metastases was 4.75 months (range 1–10).

Conclusions: Cerebral metastases of pancreatic cancer occur extremely rare. They are associated with an advanced tumor stage, commonly liver and lung metastases. All patients presenting with neurological symptoms, multifocal metastases, and significantly elevated CA 19-9 levels are suspicious of sustaining cerebral metastases and should undergo brain imaging.  相似文献   
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Nine morbidly obese subjects were studied with a test meal before and 3 months after a gastric partitioning operation. After the operation the postprandial release of plasma gastric inhibitory polypeptide was significantly increased, the plasma pancreatic polypeptide release was similar, and the serum insulin release significantly reduced as compared with the preoperative values.  相似文献   
206.
Abstract: Pancreatic cancer is a major health problem because of the aggressiveness of the disease and the lack of effective systemic therapies. Melatonin (MEL) has antioxidant activity and prevents experimental genotoxicity. The specific inhibitor of cyclooxygenase‐2 (COX‐2), celecoxib (CEL), increases the efficacy of chemoradiotherapy in advanced pancreatic cancer. The objective of the study was the comparison and synergic effect of MEL and CEL during either the induction or progression phases of the tumor process, measuring parameters of oxidative stress, number of tumor nodules and survival of animals with pancreatic cancer. Pancreatic cancer was induced by N‐nitrosobis (2‐oxopropyl)amine) (BOP) in Syrian hamsters. Melatonin and/or CEL were administered during the induction, postinduction as well as during both phases. The presence of tumor nodules were observed macroscopically in pancreatic and splenic areas, and the levels of lipoperoxides (LPO), reduced glutathione (GSH), superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH‐Px) in pancreatic tissue were measured. The increases in tumor nodules and LPO as well as the reductions in GSH and enzymatic antioxidants in the pancreas induced by BOP were related to a lower survival rate of animals. The administration of MEL exerted a more potent beneficial effect than CEL treatment on the reduction in tumor nodules, oxidative stress and death of experimental BOP‐treated animals. The combined treatment only exerted a synergistic beneficial effect when administered during the induction phase. Melatonin by itself had significant beneficial actions in improving the survival of hamsters.  相似文献   
207.
208.
Panniculitis can be the initial presentation of both alpha‐1 antitrypsin deficiency and pancreatic disease. They can both present with abscess‐like draining nodules, but may present like other forms of panniculitis with erythematous nodules. It is important to consider these in the differential diagnosis of patients presenting with panniculitis. Alpha‐1 antitrypsin deficiency is a relatively common disorder mainly affecting the lungs and liver. It frequently goes undiagnosed, yet critical interventions can be made to minimize disease progression. Panniculitis associated with alpha‐1 antitrypsin deficiency can be difficult to treat. Pancreatic panniculitis occurs in less than 3% of patients with underlying pancreatic disease and is often associated with arthritis. Diagnosis and treatment of the underlying pancreatic disease is imperative.  相似文献   
209.
In rats, total gastrectomy (TG) has been shown to induce pancreatic hyperplasia and increased tissue concentrations of pancreatic trypsin and amylase, whereas lipase concentration was decreased. We performed total gastrectomy with the additional insertion of a duodenal tube in 17 rats. A central venous catheter was placed after 3 wk. The control groups consisted of sham-operated rats with a gastrotomy plus duodenal tube and a group of rats with only a duodenal tube. The rats received meal stimulation with a 6 mL liquid diet (3 mL oil, 2 mL amino acid solution, and 1 mL glucose) via duodenal tube upon recuperation. Blood samples were taken before as well as 5, 15, 30, and 60 minutes after the meal and analyzed for insulin, pancreatic glucagon, gastrin, and CCK by specific RIA techniques. Glucose tolerance was found to be impaired after total gastrectomy. Though insulin release was delayed compared to the controls, the integrated postprandial output was unchanged.  相似文献   
210.
Summary Ninety-two insulin-dependent diabetics (aged 4–20 years, mean±SD: 13±4) with a duration of diabetes from 2 to 17 years (7±3) were transferred from Lente or NPH (5 × crystallised insulin) to Monotard insulin (highly purified insulin). Total serum immunoreactive insulin levels and concentrations of antibodies against insulin, porcine proinsulin, a-component and pancreatic polypeptide were determined prior to [I] and at a mean of 220 [II], 460 [III], 830 [IV], and 1170 [V] days after the change. All but two subjects had insulin antibodies (IgG) at the start, with a mean value of 2864 U/ml. There was a significant fall in the mean insulin antibody level between [I] and [II] to 2165 U/ml (p<10-7), followed by an increase between [II] and [III] whereafter a slight decrease was observed being significant between [III] and [IV], as well as between [IV] and [V] (p<0.05); some patients showed a constant fall over the entire period, while others showed fluctuations. Total serum insulin showed a similar pattern, with a mean value of 1141 U/ml at [I] declining to 522 U/ml at [V]. The percentage fall between [I] and [V] was greater (54%) than that in the insulin antibodies (30%). Antibodies against acomponent, proinsulin and pancreatic polypeptide were present in 96%, 72% and 41% of the patients respectively before the change in therapy. There was a decline in these antibodies between each sampling (p values between <10-3 and 10-8) and, at the end of the investigation antibodies against a-component were above the detection limit in only 4 patients, and none of the patients showed antibodies against proinsulin or pancreatic polypeptide. Thus, removal of the impurities, including the hormonal contaminants of insulin, leads to a slow fall in antibodies to insulin and a much faster disappearance of antibodies against acomponent, proinsulin and pancreatic polypeptide.  相似文献   
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