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1.
STUDY OBJECTIVE: To evaluate the safety and efficacy of small-bore, silastic drains for patients undergoing general thoracic surgery. PATIENTS AND METHODS: Twenty-five patients who received soft, small-bore, silastic drains were compared with 17 patients who received semi-rigid double lumen (DL) tubes retrospectively. RESULTS: The pain score was significantly lower in patients who received the silastic tubes in video-assisted thoracoscopic surgery (VATS) cases on postoperative days 5 and 6 , after continuous epidural analgesia had finished (P=0.018). No specific morbidity was seen in the patients who received silastic tubes. CONCLUSION: We considered that soft, small-bore silastic drains were just as effective as traditional DL tubes, but caused less pain especially in VATS cases.  相似文献   
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The effects of testosterone (T) and 17 beta-estradiol (E2) on the prostate of castrated rats were investigated by histopathological and immunocytochemical procedures. A significant increase in prostatic weight occurred after 6 weeks treatment with T alone and in combination with E2. The greatest increase in prostatic weight occurred after the administration of T plus E2. Histopathologically, glandular hyperplasia of the prostate was noted, and the number of bromodeoxyuridine (BrdU)-positive cells showed a significant increase over that induced by testosterone alone.  相似文献   
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Objective. To assess the diagnostic value of magnetic resonance imaging (MRI) as compared with radiographic findings in osteonecrosis in divers. Design and patients. MRI scans and conventional radiographs of the shoulder, hip and knee joints of 23 professional male scuba divers were reviewed together with their clinical findings and personal histories. Correlations between the MRI findings and the radiographic evaluation, clinical symptoms, and personal history were then investigated. Results and conclusions. Lesions found on MRI in 23 divers included 27 in 39 proximal humeri, 17 in 36 proximal femora, 13 in 32 distal femora, and 12 in 32 proximal tibiae. Diffuse, marginated, or irregular patterns were observed. No lesions were seen in epiphyses of the distal femur or proximal tibia. We tried to classify these MRI findings by location and appearance. MRI showed no patients with only one affected bone. A close correlation between the MRI findings and maximum diving depth was observed in the proximal humerus. MRI depicted bone lesions that could not be detected on the radiographs. A routine MRI investigation of the hip joints should be performed in every diver in whom osteonecrosis is diagnosed at another site, for early detection of femoral head osteonecrosis. MRI of the shoulder joint is also the best surveillance in divers who dive deeper than 15?m.  相似文献   
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OBJECTIVE: It is controversial whether a systematic mediastinal lymph node dissection (MLND) needs to be performed in all patients with stage I lung cancer. The present study was done to examine the new sentinel lymph nodes hypothesis based on the lobe of the primary tumor. METHODS: In our first study, the lymph node (LN) metastases were assessed in 291 stage I non-small cell lung cancer (NSCLC) patients who had a major lung resection with a systematic mediastinal lymph node dissection. We evaluated the validity of using our new sentinel lymph nodes method based on the lobe of the primary tumor as follows: the pretracheal (#3), tracheobronchial (#4), and hilar nodes (#10) for right upper lobe tumors; #4, subcarinal (#7), and #10 for middle lobe tumors; the subaortic (#5), paraaortic (#6), and #10 for left upper lobe tumors; and the #7, #10, and interlobar nodes (#11) for tumors in either lower lobes. In the second study, we performed a lobectomy with new sentinel node sampling in 64 patients with preoperative complications. If all of the sampling nodes showed no metastases on frozen section diagnosis, systematic node dissections were not performed. RESULTS: Six of 291 patients in the first study had skip metastases that did not involve the new sentinel nodes; 5 of the 6 patients had macroscopic pleural invasion. Thus, we defined pleural invasion as an exclusion criterion for the second study. In the second study, the median follow-up time was 39 months. Metastatic lymph nodes were detected in 11 of 64 patients. Fifty-three patients (83%) had no metastasis in the sampled nodes, and, therefore, a mediastinal lymph node dissection was not done. The morbidity rate in the sampling group was 36%, and there was no mortality. In the sampling group, local recurrences were observed in two patients, distant metastases in eight, and carcinomatous pleuritis in one; the overall 5-year survival rate was 82%. CONCLUSIONS: We found that it is possible to perform a less invasive lymphadenectomy for patients with stage I lung cancer using intra-operative sampling of new sentinel lymph nodes.  相似文献   
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Twenty patients with malignant lymphomas and 12 with acute leukemias were treated with intravenous administration of etoposide, 60-100 mg/m2/day for five days, repeated for three to four weeks. Eighteen cases of malignant lymphoma and nine of acute leukemia were evaluable. CR was achieved in three cases (16.7%) and PR in four cases (22.2%) of malignant lymphoma. Although CR was not achieved in any patients with acute leukemia, and PR was in three (33.3%), it was found that etoposide was most effective for the patients with the M4 or M5 subtype in the FAB classification. The most serious adverse effect of the drug was leukopenia in patients with lymphoma. In three patients (30.0%), the leukocyte count was lower than 1,000/mm3. Gastrointestinal complications, such as anorexia, nausea, vomiting and diarrhea occurred in 60.7% of all patients, but were not serious. Alopecia was observed in 73.1%. Intravenous administration of etoposide was apparently effective for the patients with malignant lymphoma of the diffuse mixed type, and this efficacy found in our study was the same as that for oral administration of etoposide reported by us previously.  相似文献   
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MSM/Ms is an inbred strain derived from the Japanese wild mouse, Mus musculus molossinus. It is believed that subspecies molossinus has contributed substantially to the genome constitution of common laboratory strains of mice, although the majority of their genome is derived from the west European M. m. domesticus. Information on the molossinus genome is thus essential not only for genetic studies involving molossinus but also for characterization of common laboratory strains. Here, we report the construction of an arrayed bacterial artificial chromosome (BAC) library from male MSM/Ms genomic DNA, covering approximately 1x genome equivalent. Both ends of 176,256 BAC clone inserts were sequenced, and 62,988 BAC-end sequence (BES) pairs were mapped onto the C57BL/6J genome (NCBI mouse Build 30), covering 2,228,164 kbp or 89% of the total genome. Taking advantage of the BES map data, we established a computer-based clone screening system. Comparison of the MSM/Ms and C57BL/6J sequences revealed 489,200 candidate single nucleotide polymorphisms (SNPs) in 51,137,941 bp sequenced. The overall nucleotide substitution rate was as high as 0.0096. The distribution of SNPs along the C57BL/6J genome was not uniform: The majority of the genome showed a high SNP rate, and only 5.2% of the genome showed an extremely low SNP rate (percentage identity = 0.9997); these sequences are likely derived from the molossinus genome.  相似文献   
9.
The body of a Japanese flounder (Paralichthys olivaceus) changes from a symmetrical to an asymmetrical form during metamorphosis. To obtain detailed information on the mechanisms of the migration of the right eye to the left side, soft and hard tissues in the head of larval flounders were examined using transmission electron microscopy (TEM). Retrorbital vesicles (Rvs) are pairs of sac-like structures under the eyes. It has been suggested that the asymmetrical development of Rvs, with the right (blind) one being bigger than the left, is the driving force behind eye migration. The present study revealed that the ultrastructure of the Rv sheath is quite similar to that of a lymphatic capillary. Thus, it is possible that the Rv is a part of the lymph system, and is probably related to the secondary vascular system in teleosts. If we assume that the Rv sheath has a high permeability to liquid, similar to lymphatic capillaries, it is not plausible that the active expansion of the Rv pushes the eyeball. On the other hand, the pseudomesial bar (Pb) is a bone that is unique to flounders and is present only on the right (blind) side. At the beginning of eye migration, an aggregation of fibroblast-like cells is observed in the dermis under the right eye, where the Pb will subsequently be formed. These cells have a well-developed rough endoplasmic reticulum (rER) and mitochondria, and are probably responsible for formation of the thick layers of collagen fibrils around them. Since it is unlikely that the active expansion of the Rv causes eye migration, the role played by the Pb and its rudiment becomes more significant in right eye migration in the Japanese flounder becomes more significant.  相似文献   
10.
Vascular tumors of the soft tissue display a wide spectrum of histologic features and biologic behavior. Flow cytometric DNA analysis was performed on 40 vascular tumors, including nine African endemic-type Kaposi's sarcomas, nine angiosarcomas, seven hemangiopericytomas, six glomus tumors, and nine capillary hemangiomas. Six of the nine angiosarcoma cases (67%) and one of the seven hemangiopericytomas cases (14%) were aneuploid. All benign vascular tumors and Kaposi's sarcomas were diploid. Clinically, five of the six angiosarcoma patients with aneuploidy died within 2 to 28 months, while the remaining patient, who had the smallest tumor (2 x 1 cm), survived more than 4 years after the initial diagnosis was made. All three angiosarcoma patients with diploidy died within 10 to 14 months. One hemangiopericytoma patient with aneuploidy died within 1 month. No cases of benign tumor recurred. These results suggest that most vascular tumors, which generally follow a benign clinical course, were diploid and that the majority of those with a poor outcome were aneuploid. However, flow cytometrically assessed DNA ploidy has no prognostic value in angiosarcomas or hemangiopericytomas.  相似文献   
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