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41.
A 61-year-old female was admitted to our hospital with epigastric pain and fever. The laboratory data showed severe inflammatory reactions. Computed tomography revealed an irregular tumor in the left hepatic lobe and swelling of lymph nodes. 18F-fluorodeoxy-glucose positron emission tomography (FDG-PET) showed high uptake by the tumor, with diffuse uptake in the spine. Based on the elevated leukocyte count and FDG-PET findings, the patient was diagnosed with a granulocyte colony-stimulating factor (G-CSF)-producing tumor (G-CSF, 213 pg/mL). We performed left trisegmentectomy of the liver, bile duct resection, and lymph node dissection. Histologically, the tumor was a poorly differentiated adenocarcinoma with some lymph nodes metastasis. Immunohistochemical staining of the tumor cells was positive for G-CSF. Therefore, the tumor was diagnosed as G-CSF–producing cholangiocellular carcinoma. The inflammatory reactions and serum G-CSF level transiently improved immediately after surgery. However, 1 month later, the leukocyte count and serum G-CSF level increased again, and recurrence was observed in the remnant liver. The patient died 3 months after the operation. G-CSF–producing cholangiocellular carcinoma is rare. This tumor progresses rapidly, and surgical treatment for advanced condition should be carefully selected.Key words: Granulocyte colony-stimulating factor, Cholangiocellular carcinoma, FDG-PET, Immunohistochemistry, LeukocytosisGranulocyte colony-stimulating factor (G-CSF)-producing tumors were first reported in 1977.1 G-CSF-producing cholangiocellular carcinomas (CCCs) are rare, with only 5 other reported cases. We herein report a surgical case of G-CSF–producing CCC with early recurrence and include bibliographic comments.  相似文献   
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Phosphaturic mesenchymal tumors (PMTs) are the most typical cause of tumor-induced osteomalacia (TIO) associated with mesenchymal neoplasms. Specifically, TIO is attributed to the production of phosphatonins, such as fibroblast growth factor 23 (FGF23), participating in the homeostasis of phosphate. Although immunohistochemistry (IHC) for FGF23 showed characteristic positive staining in PMTs, FGF23 antibodies that can be used for the reliable diagnosis of PMTs are hard to obtain in common pathology laboratories. Somatostatin receptor 2A (SSTR2A) has been previously proposed as an alternatively useful marker for the diagnosis of PMTs. However, SSTR2A is not commonly utilized in pathological laboratories. The CD56 marker is a useful alternative that is comparable to SSTR2A and is similar considering the sensitivity. Even in cases of PMTs originating in the bones, ethylenediaminetetraacetic acid-based decalcification for tissue processing does not seem to affect the IHC of CD56. As CD56 immunopositivity in mesenchymal tumors is limited, it also has some degree of specificity for PMTs. Thus, when PMTs are suspected, the use of CD56 is recommended.  相似文献   
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Melanotic oncocytic metaplasia (MOM) of the nasopharynx is an extremely rare lesion, with only 21 cases reported in English literature to date. MOM typically occurs near the Eustachian tube opening in Asian men in their 60 s to 70 s. Here, we present a case of MOM in a 57-year-old Japanese man who is a heavy smoker. The patient did not have complaints; MOM was diagnosed incidentally as 4 flat elevated lesions with brown to black discoloration, ranging from 2 to 3 mm in maximal diameter, were found in the right torus tubarius. On suspecting melanoma, the largest lesion was biopsied. Microscopic examination identified both oncocytic metaplasia and melanin pigmentation of the epithelium in the same gland. Upon immunohistochemical examination, melanocytes displayed reactivity for 3 out of 4 melanocytic markers; immunopositivity for S-100 protein, Melan-A, and MITF and immunonegativity for HMB-45 was observed. Normal melanocytes in the nearby surface respiratory epithelium displayed the same pattern of immunoreactivity. Immunopositivity for S-100 protein and immunonegativity for HMB-45 have been previously reported in MOM. Reduction of stimulation of melanocytes in a longstanding lesion like MOM may explain the immunonegativity for HMB-45. S-100 protein, in conjunction with more specific marker for melanocytes, Melan-A or MITF, could prove the definite presence of melanocytes in this case of MOM. As it has been shown by previous reports that MOM pursues a benign course, it will be sufficient to follow up the patients regularly for the remaining 3 lesions.  相似文献   
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Development of malignant peripheral nerve sheath tumors (MPNSTs) is a stepwise process that involves the alteration of many cell cycle regulators and the double inactivation of the NF1 gene. Inactivation of the TP53 gene and deletion of the CDKN2A/p16 gene are known to play an important role in the process. Herein, we present a 19-year-old man with a familial history of neurofibromatosis type 1, in whom the tumor arose from the intercostal nerve and showed 3 components: a neurofibroma, a low-grade MPNST, and a high-grade MPNST. Loss of p16 expression and homozygous deletion of the CDKN2A/p16 gene were observed in both the low-grade and the high-grade MPNST. In contrast to low-grade MPNSTs, high-grade MPNSTs generally tend to lose expression of p16 and harbor homozygous deletion of the CDKN2A/p16 gene. Loss of p16 expression and homozygous deletion of the CDKN2A/p16 gene in low-grade MPNST in our case might be related to its progression to high-grade MPNST. To the best of our knowledge, this is the first study correlating the p16 expression status and CDKN2A/p16 gene alteration in low-grade MPNSTs.  相似文献   
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Background and PurposeSome de- and re-polarization patterns can reflect an increased risk of ventricular tachyarrhythmias. We studied whether some electrocardiographic (ECG) patterns are able to predict the development of ventricular fibrillation (VF) during acute myocardial infarction (MI).MethodsWe compared the patterns of ST-T segment of 78 patients who developed VF during acute MI (patient with VF) vs 170 comparable patients with acute MI but with no VF complications.ResultsOf the VF group, 47 developed out-of-hospital VF and 31 developed VF after their admission to the hospital. A steep downsloping ST segment toward a negative T wave with or without a short, flat, or rising portion at the initial portion was observed in 69.2% of the 78 patients: 61.3% in patients with pre-VF and 74.5% in patients with post-VF, vs 9.4% of patients who did not develop VF (P < .0001). In 90.6% of the latter, a typical upward-concave or convex “ischemic” pattern of the ST segment was observed. Thus, the characteristic ST-T patterns were highly associated with VF with a specificity greater than 90%.ConclusionsA steep downsloping ST segment may characterize the ECGs of patients who develop VF during acute MI.  相似文献   
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A 75-year-old woman with a history of myocardial infarction, gallstones, and right renal cancer was referred to our department because of right flank pain. She had a surgical scar on the right abdomen between the 10th and 11th ribs; computed tomography demonstrated intercostal herniation of the colon. Recognizing the possibility of adhesions of the hernia and colon, we used a median skin incision and patched a polyester mesh coated with absorbent collagen. The patient had an uneventful postoperative course, with no pain for 6 months postoperatively. Transdiaphragmatic intercostal hernias with abdominal contents commonly develop after trauma or thoracic surgery. Incisional intercostal hernias seldom develop after nephrectomy; the present case is only the fourth report. We conjecture that a costochondral incision can induce subluxation of the costotransverse joint, intercostal nerve injury, and atrophy of the intercostal and abdominal oblique muscles. Surgeons must therefore recognize the potential, albeit rare, for intercostal hernia after nephrectomy.  相似文献   
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