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101.
We have previously demonstrated the protective role of urinary trypsin inhibitor (UTI) against acute inflammatory lung injury induced by lipopolysaccharide (LPS) using UTI-deficient (-/-) mice and corresponding wild-type (WT) mice. The protection was mediated, at least partly, through inhibition of the enhanced local expression of proinflammatory cytokines, chemokines, and intercellular adhesion molecule-1. In the present study, we addressed whether UTI regulates oxidative stress generated by LPS challenge in the lung. UTI (-/-) and WT mice were treated intratracheally with vehicle or LPS (125 microg/kg). After LPS challenge in both genotypes of mice, the lung levels of mRNA for inducible nitric oxide synthase and hemo oxygenase-1 were elevated, but to a greater extent in UTI (-/-) mice than in WT mice. Immunohistochemistry showed that the formations of 8-hydroxy-2'-deoxyguanosine and nitrotyrosine in the lung were more intense in UTI (-/-) mice than in WT mice after LPS challenge. These results indicate that endogenous UTI is protective against acute lung injury induced by bacterial endotoxin, at least partly, via the antioxidative properties.  相似文献   
102.
BACKGROUND: Acute blood pressure (BP) elevation and cardiac abnormalities are known to follow ischemic stroke. Brain natriuretic peptide (BNP), which is produced in response to such cardiovascular alterations, is expected to play a hemodynamic role. We measured plasma BNP concentrations in patients with cerebral infarction (CI) to determine the implications of BNP in acute ischemic stroke. METHODS: Eighty-eight patients with CI, 59 with essential hypertension, 44 with spontaneous intracerebral hemorrhage, 22 with asymptomatic atrial fibrillation (Af), and 20 age- and sex-matched healthy volunteers were recruited in the study. CI patients were divided into 2 subgroups either having Af (27 patients) or not (61 patients). BNP levels were repeatedly measured in 58 patients with CI. BNP levels were compared between ischemic subgroups categorized by size of infarction. Correlation was investigated between BNP levels and hemodynamic parameters. RESULTS: BNP levels in CI patients were significantly higher, but they decreased in the subacute period. BNP levels in CI patients without Af were correlated with mean arterial blood pressure (MAP) on admission or the degree of reduction in MAP at day 1, while in CI patients with Af BNP levels showed negative correlation with MAP on admission. Follow-up serum sodium levels in CI patients with Af were negatively correlated with BNP levels on admission. CONCLUSIONS: This study suggests the hemodynamic implications of BNP in acute ischemic patients.  相似文献   
103.
Peripheral vascular disease (PVD) has been reported to cause deterioration in insulin sensitivity. The precise mechanism of insulin resistance induced by PVD has not been clarified. To elucidate the mechanism causing impaired insulin action and glucose metabolism under peripheral ischemic conditions, we determined glucose turnover and glucose tolerance in hindlimb-ischemic (FAL) rats. The right femoral artery was ligated in hindlimb-ischemic (FAL) rats, while the artery was only exposed in the Sham operated (Sham) rats used as a control. Two weeks after the ligation, glucose tolerance was impaired and plasma insulin levels were significantly increased in FAL rats compared with Sham rats after intraperitoneal glucose loading (2 g kg(-1)). Under euglycemic hyperinsulinemic clamp conditions, the glucose infusion rate was significantly lower in FAL rats compared with Sham rats, but there was no significant difference in the glucose disappearance rate between the two groups. Hyperinsulinemia suppressed endogenous glucose production by 50% in Sham rats, while the suppression was 20% in FAL rats, indicating hepatic insulin resistance in FAL rats. mRNA analysis of isolated liver after the clamp experiment revealed that glucokinase mRNA, but not PEPCK and glucose-6-phosphatase mRNA, was significantly lower in FAL rats compared with Sham rats. In conclusion, chronic hindlimb ischemia impaired glucose tolerance associated with insulin resistance in the liver rather than the peripheral tissues.  相似文献   
104.
A 65-year-old man was referred to our hospital for evaluation of his huge abdominal tumor. He was diagnosed as having a gastrointestinal stromal tumor arising from the stomach. Seven months after surgery, multiple liver metastases and mesenteric dissemination occurred. He was medicated with STI571, which works by blocking proliferation of malignant cells with expression of c-kit. The tumors shrank and serum lactate dehydrogenase and alkaline phosphatase concentrations fell to below the normal limit three months later. STI571 was effective medicine for the metastatic gastrointestinal stromal tumor for six months in this case.  相似文献   
105.
One major problem for patients with myelomeningocele (MMC) is fecal incontinence. To prevent this problem, fetal surgery for repair of MMC has been recently undertaken. The strategy behind this surgery is to allow normal development of anal sphincter muscles. The purpose of this study was to determine whether fetal surgery for repair of MMC allows normal development of anal sphincter muscles. Myelomeningocele was surgically created in fetal sheep at 75 days of gestation. At 100 days of gestation, fetal surgery for repair of the MMC lesion was performed. Three repair methods were used: standard neurosurgical repair (4 fetal sheep), covering the MMC lesion with Alloderm (2 fetal sheep), and covering the MMC lesion with Gore-Tex (2 fetal sheep). After the sheep were delivered (140 days of gestation), external and internal anal sphincter muscles were analyzed histopathologically. In control fetal sheep (not repaired) anal sphincter muscles did not develop normally. In contrast, in fetal sheep that underwent repair of the MMC, the external and internal anal sphincter muscles developed normally. Histopathologically, in the external sphincter muscles, muscle fibers were dense. In the internal sphincter muscles, endomysial spaces were small, myofibrils were numerous, and fascicular units were larger than those in unrepaired fetal sheep. There was no difference in muscle development for the repair methods. Fetal surgery for repair of MMC allows normal development of anal sphincter muscles.  相似文献   
106.
Tamura Y  Kuroiwa T  Doi A  Min KY 《Neurosurgery》2004,54(1):209-11; discussion 211-2
OBJECTIVE AND IMPORTANCE: Thymic carcinoma is an uncommon malignant tumor that is different from thymoma. Cranial and brain metastases from this tumor are extremely rare. We report a thymic carcinoma with cranial metastasis and discuss the behavior of this tumor. CLINICAL PRESENTATION: A 50-year-old man presented with headache and a palpable scalp tumor. Computed tomographic scans and magnetic resonance images revealed an osteolytic tumor with intradural and extracranial extension in the right occipital bone. INTERVENTION: After gross total resection and histological diagnosis, further investigation revealed a primary thymic tumor in the anterior upper mediastinum and liver metastases. The patient received multiple-cycle chemotherapy (cisplatin and gemcitabine) for primary and metastatic lesions. CONCLUSION: Thymic carcinoma has a poor prognosis because of a high degree of malignancy, early metastasis, and delayed diagnosis. Thus, treatment of a patient with this tumor calls for prompt diagnosis, surgical treatment, and optimal adjuvant therapy.  相似文献   
107.
108.
The efficacy of technetium-99m methoxyisobutylisonitrile (99mTc-MIBI)-guided surgery for detecting abnormal parathyroid glands in patients with secondary hyperparathyroidism (2-HPT) was evaluated and compared with the results from the same examination in patients with primary hyperparathyroidism (1-HPT). The results were also compared with those found by ultrasonography (US) and preoperative 99mTc-MIBI scintigraphy was also made. At operation 99mTc-MIBI accumulated in 64 nodules of 15 cases of 2-HPT, and all of 60 parathyroid swellings were detected (true-positives 60, sensitivity 100%, accuracy 94%). In the cases of 1-HPT, 99mTc-MIBI revealed 11 hot nodules in 10 cases, and the evaluation was true-positive 10, sensitivity 100%, and accuracy 91%. US and preoperative 99mTc-MIBI scintigraphy in patients with 2-HPT had a sensitivity of 75% and 67% and an accuracy of 70% and 66%, respectively. The usefulness of 99mTc-MIBI-guided surgery for detecting abnormal parathyroid tissue in 2-HPT patients was similar to that in 1-HPT patients but was superior to US and preoperative 99mTc-MIBI scintigraphy. Intraoperative 9mTc-MIBI for patients with 2-HPT is effective and makes the surgery easier, especially when the parathyroid glands are ectopic or when a few glands are markedly enlarged but the other glands are atrophied.  相似文献   
109.
OBJECTIVE: The purpose of our study was to compare the detectability of malignant hepatic tumors on ferumoxides-enhanced MRI using five gradient-recalled echo sequences at different TEs. MATERIALS AND METHODS: Ferumoxides-enhanced MRIs obtained in 31 patients with 50 malignant hepatic tumors (33 hepatocellular carcinomas, 17 metastases) were reviewed retrospectively by three independent offsite radiologists. T1-weighted gradient-recalled echo images with TEs of 1.4 and 4.2 msec; T2*-weighted gradient-recalled echo images with TEs of 6, 8, and 10 msec; and T2-weighted fast spin-echo images of livers were randomly reviewed on a segment-by-segment basis. Observer performance was tested using the McNemar test and receiver operating characteristic analysis for the clustered data. Lesion-to-liver contrast-to-noise ratio was also assessed. RESULTS: Mean lesion-to-liver contrast-to-noise ratios were negative and lower with gradient-recalled echo at 1.4 msec than with the other sequences. Sensitivity was higher (p < 0.05) with gradient-recalled echo at 6, 8, and 10 msec and fast spin-echo sequences (75-83%) than with gradient-recalled echo sequences at 1.4 and 4.2 msec (46-48%), and was higher (p < 0.05) with gradient-recalled echo sequence at 8 msec (83%) than with gradient-recalled echo at 6 msec and fast spin-echo sequences (75-78%). Specificity was comparably high with all sequences (95-98%). The area under the receiver operating characteristic curve (A(z)) was greater (p < 0.05) with gradient-recalled echo at 6, 8, and 10 msec and fast spin-echo sequences (A(z) = 0.91-0.93) than with gradient-recalled echo sequences at 1.4 and 4.2 msec (A(z) = 0.82-0.85). CONCLUSION: In the detection of malignant hepatic tumors, gradient-recalled echo sequences at 8 msec showed the highest sensitivity and had an A(z) value and lesion-to-liver contrast-to-noise ratio comparable with values from gradient-recalled echo sequences at 6 and 10 msec and fast spin-echo sequences.  相似文献   
110.
We report a case of right giant hydronephrosis. A 68-year-old man was admitted to our hospital with chief complaints of general fatigue, loss of appetite and a one-year history of progressive fullness on whole abdomen. Abdominal computed tomography scan exhibited a huge, homogeneous, low density mass originating from the right kidney. We performed right percutaneous nephrostomy and drained over 6,500 ml bloody fluid. Cytological examination of the drained fluid revealed atypical nuclear appearance defined as class III. Increased values of carbohydrate antigen 19-9 were observed both in the fluid as well as in the serum. We performed right nephrectomy. Macroscopic appearance of the resected kidney showed marked stenosis at the portion of ureteropelvic junction. Histological analysis of the stenotic portion demonstrated marked fibrosis without findings of malignancy.  相似文献   
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