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101.
Primary cutaneous B-cell lymphoma in Japanese patients   总被引:1,自引:0,他引:1  
Primary cutaneous B-cell lymphoma (PCBCL) is a rare group of lymphoproliferative disorders. There have been few reports of Japanese patients with PCBCL, so the present study investigated the clinicopathological and immunological features and Bcl-2 gene rearrangement and protein expression in 28 Japanese patients with PCBCL. According to the Revised European-American Lymphoma (REAL) classification, there were 25 diffuse large B-cell lymphomas (DLBCL), one Burkitt type lymphoma, one lymphoblastic lymphoma and one marginal zone cell lymphoma. Of the 25 DLBCL, 17 were in males and eight in females, with an average age of 69.4 years. Follow-up data were available in 19 cases of DLBCL of which seven died and 12 were alive. The overall 5-year survival rate was 61%. Cases of DLBCL involving the legs were found to have poorer clinical outcomes; two of four cases with leg lesions died, with a mean survival of 13 months. Of 14 cases with non-leg lesions, four died, and the mean survival was 38.9 months. Only one case of Burkitt type lymphoma was CD10 positive. Bcl-2 rearrangement was not observed in 13 cases studied by polymerase chain reaction. Bcl-2 expression was observed in nine of 13 cases studied. All five cases with leg lesions exhibited Bcl-2 expression, but four of six cases with non-leg lesions also expressed the protein. These results show that DLBCL is the most frequent subtype of PCBCL in Japanese patients and that the prognosis of Japanese patients with DLBCL is worse than that of reported European cases. The study also found that PCBCL was frequently associated with Bcl-2 expression, which was not site-confined, and that there was no evidence for a follicular center origin of PCBCL.  相似文献   
102.
Natural tooth loss represents a major medical issue within the elderly population, since it impairs masticatory function critical for oral intake of essential nutrition. Contribution of genetic factors has been implicated in the determination of natural tooth loss; degree of reduction in number of natural teeth remaining intact (NTI) varies among individuals; thus, heterogeneity in NTI might reflect genetic variation within the population. One candidate gene, the matrix Gla protein gene (MGP), has been implicated in the pathogenesis of bone loss through a repression of bone/tooth formation. We have investigated a possible association between the CA repeat polymorphism at the human MGP gene locus and the NTI in 458 elderly Japanese women. In 916 chromosomes tested, ten alleles of the polymorphic nucleotide repeat were observed (designated A1–A10), among which five alleles were regarded as major alleles to be tested for the association. Twenty-seven women who possessed an A6 allele (164 bp) had significantly higher NTI than the remaining participants (n=431), who did not carry an allele of that size (mean: 10.0 teeth vs 5.6 teeth; P=0.007, Mann-Whitney test). An eight-year longitudinal follow-up study of NTI suggested that the genetic variations at the MGP locus did not affect the rate of tooth loss in the elderly period. These results suggest that genetic variation at the MGP gene locus is associated with some determinants for tooth loss in elderly women.  相似文献   
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104.
We compared the expression of cell adhesion molecules (CAMs), cytotoxic granule proteins, and apoptosis-related proteins by immunohistology and in situ terminal deoxynucleotidyl transferase-mediated digoxigenin-dUTP nick end labeling (TUNEL) of 10 cases of cutaneous CD56+ NK/T cell lymphoma with and 6 cases without angiodestruction. Lymphoma cells in cases with angiodestruction frequently expressed CAMs CD2, CD11a, and CD49d and their ligands CD58, CD54, and CD106 and were positive for CD122 and cytotoxic granule proteins TIA1, perforin, and granzyme B. Lymphoma cells in cases without angiodestruction mostly were negative for CD2, CD58, CD54, CD106, and TIA1 and weakly positive for perforin and granzyme B. In the TUNEL method, mean apoptotic indices (AI) for cases with angiodestruction showed a higher percentage than those without angiodestruction. CD95L, CD95, apoptosis-induced cysteine protease CPP32, apoptosis-promoting protein Bax, and proliferating marker (MIB1) frequently were positive in the lymphoma cells of cases with angiodestruction, but there was no expression of apoptosis-inhibitor protein Bcl2. In most cases without angiodestruction, lymphoma cells were positive for CD95L and Bax and negative for CD95, CPP32, and MIB1. CAMs and the 3 cytotoxic granule proteins and an apoptosis pathway might be important factors in the paracrine and autocrine mechanisms of tissue necrosis in cutaneous CD56+ NK/T cell lymphoma.  相似文献   
105.
A rare case of serous papillary cystadenocarcinoma of the ovary showing chondrosarcomatous differentiation in a metastatic deposit late in the clinical course is reported. A 49-year-old female underwent a total abdominal hysterectomy with bilateral salpingo-oophorectomy for bilateral ovarian tumors. Histological diagnosis was serous papillary cystadenocarcinoma of both ovaries with lymph node metastasis. After six courses of chemotherapy, she was confirmed to be in complete remission following a second laparotomy. Following additional chemotherapy, a third laparotomy disclosed swollen left inguinal lymph nodes. In one of these nodes, approximately 5.0 cm in greatest diameter, the predominant histological features were: chondrosarcoma of the bone and soft tissue, with small foci of serous papillary adenocarcinoma and squamous epithelium. A histological transition between mesenchymal and epithelial areas was identified. Immunohistochemical positivity for broad-spectrum cytokeratin (AE1/AE3), vimentin, epithelial membrane antigen, and S-100 protein was observed in both chondrosarcomatous and epithelial areas. The current evidence may suggest that the chondrosarcomatous differentiation was derived from the metastatic epithelial component.  相似文献   
106.
The present study was designed to clarify the more precise ultrastructural feature of granules, especially mucous granules in the early postnatal rat parotid gland by using rapid freezing followed by freeze-substitution fixation. The parotid gland of Wistar rats (aged 0-10 days) was removed under anesthesia and immediately underwent cryofixation followed by substitution with osmium tetroxide. After fixation, the samples were embedded in Epon-Araldite, cut into ultrathin section, and then examined by transmission electron microscopy. Electron microscopy showed that the mucous granules of samples treated by freeze-substitution fixation had low electron density and were almost spherical in shape with a clear limiting membrane. By Day 5, granules that were a little more electron dense than mucous granules, granules with a more electron dense portion at their periphery, and heterogeneous granules with an internal highly electron dense portion were found. Moreover, cells containing both homogeneous granules with a high electron density similar to that of mature serous granules and heterogeneous granules were observed. These findings demonstrated that the morphology of the transforming-type mucous granules by chemical fixation in the previous study was an artifact and, as a result, strongly suggested that on the sequential morphological changes of transitional mucous/serous granules by rapid freezing method in the present study, the mucous cells in the early postnatal rat parotid gland undergo transformation to serous cells.  相似文献   
107.
The purposes of the present study were to examine the response of the skin blood flux (SBF) in the paralyzed lower limbs of persons with spinal cord injury (PSCI) and to clarify the relationship between the SBF and core temperature during prolonged arm exercise. Eight male PSCI with lesions from T6 to L5 and six male control subjects (CS) participated in this study. The subjects rested for 60 min and then performed arm-cranking exercise at 20 W for 30 min at 25 °C. The tympanic membrane temperature (T ty) and SBF in the anterior thigh (SBFT) and in the posterior calf (SBFC) were continuously measured throughout the experiment. The SBFC did not change in either PSCI or CS during the experiment. The SBFT in four PSCI with high lesions (T6 to T12), remained unchanged during exercise. The SBFT in the other four PSCI with low lesions (T12 to L5, SBFT+) began to elevate markedly when the T t, exceeded a threshold temperature of 36.69 °C. The pattern of increase of SBFT in SBFT+ was similar to that in CS, although onset of the increase in SBFT was delayed and the peak of SBFT during exercise was significantly lower in comparison with the CS. We consider that these differences between the SBFT+ and CS were largely attributable to the lowerT ty in the former group, which took a prolonged time to reach the threshold of 36.69 °C.  相似文献   
108.
A case of lymphomatoid granulomatosis (LYG) involving the lungs, skin, stomach, and possibly the left kidney in a 60-year-old man is presented. The infiltrates in the lungs, stomach, and skin showed a polymorphic appearance, and consisted predominantly of lymphocytes of mature and blastic form and of a few neutrophils, plasma cells, and histiocytes. Most lymphoid cells showed irregularly shaped nuclei and clustered dense bodies, characteristics indicative of T lymphocytes. An immunohistochemical study confirmed the T cell origin of the lymphocytes; i.e. they were positive for Leu-1, Leu-3a and la-like antigens but negative for Leu-2a antigen and the antibodies against light chains. The homogeniety of the major population of infiltrates in LYG indicates that at least some forms of LYG may be neoplastic or pre-neoplastic lymphocytic disorders which may ultimately progress to malignant lymphoma. ACTA PATHOL. JPN. 35 : 711–721, 1985.  相似文献   
109.
110.
A large tumor massively occupying the left pleural cavity had the Andings of both typical carcinoid and oncocytoma which were thought to be of bronchogenic origin. The ultrastructural observation of the tumor revealed a mixture of rod-shaped granules in addition to usual round neurosecretory ones. In the nuclei of dark cells of the oncocytoma, a latticed or hatched structure was detected. Besides two adenomas and hyperplastic foci of large acidophilic cells in the thyroid, a black adenoma and cortical adenoma in the adrenal gland, were detected. Moreover, there was an ectopic adrenal gland in the retroperitoneum. Briefly it was suggested that the bronchial carcinoid presented may be related to multiple endocrine adenomatosis.  相似文献   
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