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51.
52.
OBJECTIVE: Sentinel lymph node (SLN) biopsy is an integral part of the surgical management of patients with breast cancer. Rapid immunohistochemistry (RIHC) has the potential to increase detection of metastatic carcinoma at the time of frozen section consultation. The authors assessed the accuracy and turnaround time of a newly developed RIHC method for pancytokeratin (RIHC-CK). METHODS: Sixty-six SLNs from 32 patients with breast carcinoma were examined for metastasis using the Zymed Sentinel Lymph Node Rapid IHC Kit. Intraoperative frozen sections (6 mum) of the SLNs were incubated with Zymed anti-pan-cytokeratin/HRP conjugate, diaminobenzidine (DAB), and stained with hematoxylin. Slides were ready within 8 minutes and were interpreted as positive or negative for metastatic carcinoma. Results were compared with previous intraoperative touch preparations, frozen sections, hematoxylin and eosin (Perm H&E), and AEl/3-immunostained permanent sections (Perm CK). RESULTS: Fourteen lymph nodes (19%) in 13 patients tested positive for metastatic carcinoma in Perm H&E, the gold standard. RIHC-CK had the highest sensitivity (92%) of the intraoperative tests, compared with touch preparations (64%) and frozen sections (80%). RIHC-CK showed 94% accuracy, compared with 96% (frozen section) and 93% (touch preparation). The RIHC technique took 8 minutes and was easy to perform and interpret. CONCLUSIONS: Zymed RIHC is a sensitive method for detecting breast cancer metastases in SLNs. The speed, accuracy, and ease of interpretation of the test allow for recognition of micrometastases (<2 mm) that might otherwise be undetectable by current methods of intraoperative evaluation. The prognostic significance and effect on surgical management of micrometastases in SLNs have yet to be determined.  相似文献   
53.
The pathologies of many infectious, autoimmune and malignant diseases are influenced by the profiles of cytokine production in pro-inflammatory (TH1) and anti-inflammatory (TH2) T cells. Interindividual differences in cytokine profiles appear to be due, at least in part, to allelic polymorphism within regulatory regions of cytokine gene. Many studies have examined the relationship between cytokine gene polymorphism, cytokine gene expression in vitro, and the susceptibility to and clinical severity of diseases. A review of the findings of these studies is presented. An on-line version featuring appropriate updates is accessible from the World Wide Web site, http://www.pam.bris.ac.uk/services/GAI/cytokine4.htm.  相似文献   
54.
Periprosthetic osteolysis involves osteoclast activation by wear particulates and their exposure to mechanical perturbation through exposure to shear forces generated by periprosthetic fluid as well as interface micromotion. This study aimed to determine the interactions between wear particulates, mechanical stimulation, and osteoclasts. In static cultures, wear particulates increased osteoclast differentiation. Addition of neutralizing antibodies to RANKL (receptor activator of nuclear factor kappa ligand) inhibited the particle-induced increase in osteoclast numbers. Cyclic 5000 microstrains were applied with the use of a custom-built device to marrow-derived cultures to assess the effect on osteoclast differentiation. Mechanical strain application alone decreased osteoclast differentiation, which was further decreased by the addition of particles despite increases in the soluble RANKL to osteoprotegerin (OPG) ratio. Mechanical strain alone induced mature osteoclast apoptosis in a dose-dependent manner. In contrast, in the mature osteoclast model, the addition of nonmetal particulates protected the osteoclasts from becoming apoptopic. Titanium (Ti) and cobalt chromium (CoCr) particles, however, induced osteoclast apoptosis, whereas polyethylene (PE) and polymethylmethacrylate (PMMA) did not. Wear particulates and mechanical stimulation interact via an eicosanoid-dependent pathway to alter osteoclast function and survival. The addition of mechanical perturbation to a particle-laden system thus appears to enhance the potential for osteolytic activity by enhancing osteoclast survival.  相似文献   
55.
Voluntary and forced exercise decrease morbidity and mortality in laboratory animals. Caloric restriction has similar effects on health and unique benefits on life span. Nonetheless, in most experiments, animals do not have access to physical activity and are fed ad libitum (AL). We hypothesized that with regular access to either unlimited running wheel exercise (EX) or limited physical activity (PA), key biomarkers of health would be enhanced enough to counter some consequences of a sedentary AL lifestyle. This 16-month study compared body weight, tumor number and size, tissue lesions, oxidative stress, and reactive stress in (1) sedentary animals with no access to physical activity (SED); (2) animals with access to hour-long, twice weekly activity in a large box (PA); and (3) animals with access every other day to a running wheel (EX). At the end of the study, EX body weight was 8-9% lower than PA and SED. In addition, EX had no kidney lesions versus 50% in PA and SED, and had smaller tumor size (10+/-2 vs. 14+/-4 and 30+/-4 mm). Exhaustive exercise lowered glutathione/oxidized glutathione ratio in EX and PA, but in SED, the ratio was depressed even in resting animals. In all treatments, prolactin (PRL) levels were lower in resting animals than in acutely exercised animals. In conclusion, EX had the most favorable health biomarkers while SED had the least. PA did not confer gross health benefits different than the SED group, but was biochemically more similar to EX animals.  相似文献   
56.
The Psychopathy Checklist-Revised (PCL-R; R. D. Hare, 1991) is an often-used device for assessment of adult antisociality. This research examined generalizability by replicating the 2-factor model for a sample of 326 male prisoners and assessing its congruence and relative reliability and specificity among 620 substance-dependent patients. Generality was assessed also across addiction subtypes (opioid, cocaine, and alcohol), age, gender, and ethnicity. The 2-factor model was found inappropriate for the substance-dependent samples, whereas a unidimensional model represented by the PCL-R total score was found generalizable across prison and substance-dependent samples.  相似文献   
57.
Molecular analyses of thyroid tumors have documented mutations in the tumor suppressor p53 gene almost exclusively in anaplastic carcinomas. In contrast, immunohistochemistry has localized p53 in differentiated papillary and follicular thyroid cancers. To establish the significance of p53 immunolocalization in these lesions, 78 thyroid tumors of follicular derivation were examined. All tumors were classified by strict criteria and the extent of tumor was determined morphologically. Immunohistochemical staining for p53 was performed on paraffin sections of formalin-fixed tumor tissue. The results of staining were correlated with diagnosis, tumor extent and clinical outcome. Immunopositivity for p53 was diffuse and strong in all five anaplastic carcinomas examined. There was no staining in five of six follicular adenomas. Four of nine follicular carcinomas had some degree of nuclear staining, but this was focal; all nine tumors were confined to the thyroid at the time of examination. Of 49 papillary carcinomas, 26 were intrathyroidal, and 7 of these were occult; there was no p53 positivity in any occult lesion and only 5 of the 19 palpable lesions stained. In contrast, among 23 papillary carcinomas with extrathyroidal extension or metastases, only 9 were negative for p53 immunoreactivity. Five of seven tall cell papillary carcinomas and one of two insular carcinomas had p53 immunopositivity and this correlated with aggressive behavior. These results support the tumorigenic role of p53 mutations postulated for anaplastic thyroid carcinomas and indicate that localization of p53 by immunohistochemistry is a useful prognostic index of clinical behavior in differentiated thyroid carcinomas of follicular cell derivation.  相似文献   
58.
Fifty isolates of Escherichia coli serogroup O111 recovered from humans and various animal species over a 24-year period (1976-1999) were examined for typical virulence-associated factors and susceptibilities to antimicrobials of human and veterinary significance. Nine H (flagellar) types were identified including nonmotile (n = 24), 32 (n = 12), negative (n = 5), and 56 (n = 3). Thirty-five (70%) isolates possessed at least one Shiga-toxin-producing E. coli (STEC)-associated virulence determinants (eae, stxl, stx2, hlyA) via PCR analysis. Of these 35 isolates, 20 possessed eae, stxl, and hlyA genes, whereas three isolates possessed eae, stxl, stx2, and hylA genes. Multiple antibiotic resistance was observed in 70% of the 50 E. coli O111 isolates. The majority of isolates displayed resistance to streptomycin, sulfamethoxazole, tetracycline, and kanamycin. Bacterial resistance to ampicillin, gentamicin, chloramphenicol, trimethoprim and apramycin was also observed. Integrons were identified in 23 (46%) of the E. coli isolates assayed, with a 1-kb amplicon being most frequently observed. DNA sequencing of these integrons revealed the presence of the aadA gene, encoding resistance to streptomycin. Two integrons of 1.5 and 2 kb contained the aadA2 and either dfrI or dfrXII genes, encoding resistance to streptomycin and trimethoprim, respectively. Integrons were also identified from isolates dating back to 1982. Isolates were further genetically characterized via ribotyping, which identified 15 distinct ribogroups, with 62% of isolates clustering into four major ribogroups. Certain riboprint patterns from different animal species, including humans, were observed in isolates spanning the 24-year collection period, suggesting the dissemination of specialized pathogenic O111 clones.  相似文献   
59.
AIMS: Cancer cells frequently express antigens capable of being recognized by the host immune system; however, any resultant immune response is often ineffective. This may be related in part to tumor-induced defects in antigen presentation. We screened for dendritic cell infiltration, tumor MHC II expression and associated lymphocytic reaction in the context of three established breast tumor antigens. METHODS: Forty primary breast tumors were evaluated by immunohistochemical techniques for expression of her2/neu, p53, and MUC1 and MHC class II molecules. Twenty-five samples were further analyzed for p53 mutations by PCR-SSCP analysis and DNA sequencing. The phenotype of tumor-infiltrating inflammatory cells was evaluated using the following markers: CD1a, MHC Class II, CD3, CD45, and CD45RO. RESULTS: Tumors with p53 mutations and overexpression, but not her2/neu or MUC1 overexpressing tumors, more frequently harbored marked CD1a+ dendritic cell infiltrates. An overall correlation between CD1a+ cell infiltrates and HLA class II expression on tumor cells (p = 0.0008) was also observed and these tumors had greater CD45RO+ lymphocytic infiltrates. CONCLUSIONS: In breast cancer, p53 mutations may present a more visible signal to the immune system and hence provide a better target for immunotherapy. Infiltrating CD1a positive cells are associated with a more dense tumor lymphocytic infiltrate and tumor cell expression of MHC II molecules.  相似文献   
60.
Thirty-two patients with seat belt-induced injuries to the jejunum and ileum are reviewed. These patients are classified into 3 groups according to the nature and mechanism of injury. Group I consists of 4 patients with complete transection of the proximal jejunum caused by deceleration forces. Injuries commonly associated include spleen rupture and perforation of the transverse colon and splenic flexure. Group II consists of 6 patients with infarcted ileum caused by crushing forces. Associated injuries include tears to the cecum, aorta, and inferior vena cava. Group III consists of 22 patients with blowout perforations of the jejunum and ileum. These injuries are caused by transmitted forces. There are no associated specific injuries related to this group.
Resumen Se revisaron treinta y dos casos de lesiones del yeyuno y del íleon por cinturones de seguridad (automotrices). Los pacientes fueron clasificados en tres grupos de acuerdo a la naturaleza y mecanismo de la lesión. El grupo I consistió de 4 pacientes con transección completa del yeyuno proximal causada por fuerzas de desaceleración. Como lesiones frecuentemente asociadas aparecieron la ruptura del bazo y la perforación del colon transverso y del ángulo esplénico. El grupo II consistió de 6 pacientes con infarto del íleon causado por fuerzas de machacamiento. Como lesiones asociadas se encontraron desgarros del ciego, de la aorta y de la vena cava inferior. El grupo III consistió de 22 pacientes con perforación por estallido del yeyuno y del íleon. Estas lesiones son causadas por fuerzas transmitidas a partir de la pared anterior del abdomen, los cuales causan una elevación repentina en la presión intraluminal del intestino delgado. No se encontraron lesiones específicas asociadas en este grupo de pacientes. La mortalidad por lesiones del intestino delgado causadas por trauma abdominal cerrado ha sido principalmente atribuida a diagnóstico tardío. Los síntomas iniciales pueden ser mínimos. El neumoperitoneo puede aparecer radiográficamente sólo en el 50% de los casos; la determinación de la amilasa sérica generalmente ha demostrado ser poco confiable. En nuestra serie la mortalidad reflejómás bien la presencia de lesiones asociadas que diagnóstico tardío. Creemos que el examen e historia clínicos cuidadosos y un buen conocimiento de los mecanismos de lesión del intestino delgado pueden alertar al cirujano para lograr un diagnóstico correcto en la mayoría de los casos.

Résumé Trente-deux observations d'accidentés présentant des lésions intestinales dues au port de la ceinture de sécurité sont rapportées. Elles se classent en trois groupes en fonction de la nature et du mécanisme des lésions. Le groupe I concerne 4 accidentés qui présentaient une section complète du jéjunum proximal provoquée par la décélération. Des lésions associées comprenaient la rupture de la rate, la perforation du colon transverse et de l'angle splénique. Le groupe II répond à 6 blessés qui présentaient un infarcissement iléal provoqué par l'écrasement. Les lésions associées répondaient à des déchirures du coecum, de l'aorte et de la veine cave inférieure. Le groupe III intéresse 22 accidentés qui présentaient des perforations du jéjunum et de l'iléon par brusque distension due elle-même à la force de la contusion, ce type de lésions par rupture ne s'accompagnant pas de lésion spécifique associée.
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