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101.
102.
Joseane C. de Castro Laila V. de Almeida Mariana Santos Cardoso Fabricio M. Silva Oliveira Denise S. Nogueira João Luis Reis-Cunha Luisa M.D. Magalhaes Bin Zhan Maria Elena Bottazzi Peter J. Hotez Lilian L. Bueno Daniella Castanheira Bartholomeu Ricardo T. Fujiwara 《Vaccine》2021,39(2):394-401
An estimated 400 million people are infected by parasites of the genus Ascaris and the existing control measures are inefficient. Vaccine development using B cell antigens is a promising strategy for increased protection against this parasite. The present study aimed at developing a chimeric protein capable of conferring protection against infection by Ascaris sp. For this purpose, we performed B-cell epitope predictions on previously described vaccine candidate proteins from Ascaris suum and the corresponding peptides were used to construct a chimeric protein. Female BALB / c mice were immunized subcutaneously in three doses at 10 day intervals with a vaccine formulation comprised of the chimeric protein together with monophosphoryl lipid A (MPLA). Control groups included protein alone, MPLA, or PBS. After challenge infection, animals vaccinated with chimeric protein plus MPLA showed a reduction of 73.54% of larval load in the lung compared to control group animals. Animals immunized with chimeric protein plus MPLA also display higher IgG response and a reduction in lung inflammation. Our study highlights how chimeric proteins containing more than one B cell epitope can enhance immune protection against helminthic infection and offer new approaches to the development of Ascaris vaccines. 相似文献
103.
Salcedo M Taja L Utrera D Chávez P Hidalgo A Pérez C Benítez L Castañeda C Delgado R Gariglio P 《International journal of experimental pathology》2002,83(6):275-286
The role of tumour suppressor genes in the development of human cancers has been studied extensively. In viral carcinogenesis, the inactivation of suppressor proteins such as retinoblastoma (pRb) and p53, and cellular oncogenes overexpression, such as c-myc, has been the subject of a number of investigations. In uterine-cervix carcinomas, where high-risk human papillomavirus (HPV) plays an important role, pRb and p53 are inactivated by E7 and E6 viral oncoproteins, respectively. However, little is known about the in situ expression of some of these proteins in pre-malignant and malignant cervical tissues. On the other hand, it has also been demonstrated that c-myc is involved in cervical carcinogenesis, and that pRb participates in the control of c-myc gene expression. By using immunostaining techniques, we investigated pRb immunodetection pattern in normal tissues, squamous intraepithelial lesions (SILs) and invasive carcinomas from the uterine cervix. Our data show low pRb detection in both normal cervical tissue and invasive lesions, but a higher expression in SILs. C-Myc protein was observed in most of the cellular nuclei of the invasive lesions, while in SILs was low. These findings indicate a heterogeneous pRb immunostaining during the different stages of cervical carcinogenesis, and suggest that this staining pattern could be a common feature implicated in the pathogenesis of uterine-cervix carcinoma. 相似文献
104.
Pablo Lapunzina Jos Ignacio Rodríguez Elena de Matteo Ricardo Gracia Felipe Moreno 《American journal of medical genetics. Part A》1995,55(3):349-355
We report on 3 patients with Mulibrey nanism (MN), or Perheentupa syndrome: the first 2 sibs from Argentina and a new patient from Spain. All 3 patients had growth failure, short stature, abnormal pigmentary retinal changes, and a J-shaped sella turcica. These findings are considered major criteria of MN. Two had pericardial constriction, which is a frequent and lifethreatening abnormality in this syndrome. MN is a rare autosomal recessive condition. Reviewing the 39 patients described so far, we have classified the anomalies into the very frequent (present in more than 66%), frequent (in at least 25%), and not frequent. Identifying the anomalies specific to MN should help its early diagnosis and treatment. © 1995 Wiley-Liss, Inc. 相似文献
105.
Background: The complications of the gastric pouch in gastric bypass surgery are well known. Since the first report of this
surgery 30 years ago, new technical aspects that make it safer and more effective have been implemented. Methods: As a modification
of gastric bypass, the authors have performed 305 vertical banded gastroplasty-gastric bypass procedures. Two groups of patients
underwent the procedure: Group I (n = 206) without a limb of jejunum interposed between the gastric pouch and the excluded
stomach, and Group II (n = 99) with a limb of jejunum interposed between the pouch and the stomach. The results regarding
excess weight loss and complications of the gastric pouch during the first year after surgery were compared. Results: Age,
sex, initial weight, body mass index, and percentage of ideal weight were similar in both groups. Excess weight loss was also
similar. The complications in Group I were 1 leak, 3 left subphrenic abscesses, 2 erosive gastritis with bleeding, 1 stenosis
of the gastrojejunostomy, 1 perforated ulcer, and 4 marginal ulcers with bleeding. Two patients in Group II developed bleeding
from the staple-line. Conclusions: These preliminary data suggest that complications of the gastric pouch can be reduced by
interposing a limb of jejunum between the pouch and the excluded stomach. This is an early experience; long-term results are
pending. 相似文献
106.
107.
Sialyl-Tn antigen (STn) is a mucin-type carbohydrate normally present in goblet cells of small and large bowel. STn expression has been demonstrated to occur in complete and incomplete intestinal metaplasia as well as in many carcinomas but in no normal gastric cell. The aim of our present study was to evaluate the distribution of STn in Helicobacter pylori chronic gastritis (HpCG) of pediatric patients. Eighteen gastric biopsies from 15 children (mean age: 11.5 years) with HpCG, 9 gastric biopsies from 9 children without H. pylori infection, and 1 heterotopic gastric mucosa in Meckel's diverticulum were immunostained using the anti-STn antibody STn1 (18/18), NCL-MUC-1 (7/18), and NCL-MUC-2 (18/18) antibodies. Also, sulfated mucosubstances were investigated with the Alcian Blue-Periodic Acid Schiff (AB-PAS), pH 1.0 stain. Although with different intensity (weak in 5/18, moderate 9/18, and intense 4/18) all cases with HpCG exhibited STn immunoreactivity. The expression of STn was found to be located mainly to the supranuclear region of the epithelial cells at the foveolae and glandular necks, with occasional cells showing diffuse cytoplasmic staining. When reactivity was intense, it was for the most part found in the cells at the neck of the glands. The mucus out of the luminal border above the positive cells was usually also stained. MUC-1 was negative (2/7) or weakly positive (5/7) in a few surface mucous cells. MUC-2 was negative (16/18) or occasionally detected in some foveolar and surface cells (2/18). AB-PAS pH 1.0 revealed the presence of sulfomucins in the cytoplasm of isolated cells of gastric pits and glands of most cases (11/15). None of these findings was observed in the control group. We conclude that STn can be identified in gastric cells of pediatric patients with HpCG and that this does not correlate with other mucosubtances markers. Thefindings could indicate that minimal intestinal metaplasia takes place in children with HpCG. 相似文献
108.
Proton magnetic resonance spectroscopy improves outcome prediction in perinatal CNS insults. 总被引:4,自引:0,他引:4
Munaf Kadri Stanford Shu Barbara Holshouser Douglas Deming Andrew Hopper Ricardo Peverini Stephen Ashwal 《Journal of perinatology》2003,23(3):181-185
OBJECTIVE: Prediction of neurologic outcome is difficult in neonates with acute nervous system injury. Previous studies using proton magnetic resonance spectroscopy ((1)H-MRS) have been used to predict short-term neurologic outcome in neonates with a variety of neurologic insults. We were interested in determining the effectiveness of combining clinical evaluation and spectroscopy obtained at the time of injury in predicting neurologic outcome at 24 months. STUDY DESIGN: We studied 33 neonates with acute central nervous system injury, 5.8+/-3.7 days of injury, owing to hypoxic-ischemic encephalopathy. Neonates were assessed using clinical variables (initial arterial pH, initial blood glucose, Sarnat score, electroencephalography) and spectroscopy (NAA/Cho, NAA/Cre, Cho/Cre, and lactate). Neonates were divided into two outcome groups: good/moderate and poor. Differences between the groups were assessed using chi(2) and t-test analyses. We analyzed the best predictors of outcome using discriminant analysis and calculated sensitivity, specificity, positive, and negative predictive values for each variable independently and in combination. RESULTS: There were significant differences between the good/moderate and poor outcome for the Sarnat score, EEG, lactate, and NAA/Cho. Spectroscopy combined with clinical variables improved sensitivity, but not specificity for predicting outcome. The presence of lactate had the best individual predictive value. Combination of the clinical with the MRS variables had the highest predictive value. CONCLUSION: Proton magnetic resonance spectroscopy done early after injury improves the ability to predict neurologic outcome at 24 months of age. 相似文献
109.
Skp2 protein expression in soft tissue sarcomas. 总被引:15,自引:0,他引:15
Andre M Oliveira Scott H Okuno Antonio G Nascimento Ricardo V Lloyd 《Journal of clinical oncology》2003,21(4):722-727
BACKGROUND: p45 S phase kinase-associated protein-2 (p45(skp2)), a member of the F-box family of proteins, is an important component of the Skp1-Cullin-F-box protein (SCF) ubiquitin-ligase complex (SCF(skp2)). The latter has been implicated in the ubiquitination and degradation of p27(kip1) (p27) and G(1)-S cell cycle progression. The expression and prognostic role of Skp2 in a large series of soft tissue sarcomas has not been previously investigated. METHODS: Clinicopathologic features and immunohistochemical expression of Skp2, p27, and Ki-67 proteins were studied in 182 cases of soft tissue sarcomas (American Joint Committee on Cancer stages II and III). Survival analyses were performed using the Kaplan-Meier method and the Cox regression model. RESULTS: The male to female ratio was 1.2:1, and the median age at the diagnosis was 53 years. The tumors were predominantly located in the lower extremities (n = 163; 90%) and had a median size of 9 cm. High Skp2 expression (> or = 10% of the cells) was identified in 68 tumors (37%), and was correlated with high grade histology (P =.002) and Ki-67 proliferative index (r = 0.44; P <.0001), but not with p27 expression (r = -0.02; P =.80). By univariate analysis, high Skp2 expression was associated with decreased metastasis-free, disease-free, and overall survival. In a multivariate model, high Skp2 expression was an independent predictor for decreased local recurrence-free, disease-free, and overall survival. CONCLUSION: These results indicate that Skp2 expression is associated with cell proliferation and a worse prognosis in soft tissue sarcomas. The lack of an inverse correlation between Skp2 and p27 suggests that additional molecular events associated with either Skp2 expression or p27 proteolysis may be operating in these tumors. 相似文献
110.
Ramtin R. Kassir Christopher H. Rassekh John B. Kinsella John Segas Ricardo L. Carrau James A. Hokanson 《The Laryngoscope》1997,107(1):56-61
To assess the role of adjuvant therapy in the treatment of osteogenic sarcoma of the head and neck, treatment and survival information from 173 patients with osteosarcoma of the head and neck was entered into a database. A meta-analysis of the data was attempted with primary emphasis on the effect of adjuvant therapy on disease outcome. The overall 5-year survival was 37%. Patients with mandibular and maxillary tumors had similar survival rates; both groups fared significantly better than patients with extragnathic tumors (P<0.001). Treatment with surgery alone was associated with significantly longer survival rates (P<0.03) than surgery with adjuvant therapy. In the majority of patients reported, information about surgical margins was not available. For this reason, the differences may not adequately represent the effect of adjuvant therapy. While there have been encouraging results with adjuvant treatment protocols for long bone osteosarcoma, the ultimate role of radiation and chemotherapy in the management of osteosarcoma of the head and neck remains unproven. Nevertheless, we recommend that adjuvant therapy be considered due to the poor prognosis in osteosarcoma of the head and neck. 相似文献