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101.

Background

The differential diagnosis for pediatric prepubertal vaginal bleeding is wide. Rare etiologies include vascular malformations and tumors, such as infantile hemangiomas (IHs), which validate the usefulness of exam under anesthesia, vaginoscopy, and tissue diagnosis.

Case

We report a case of an IH in a 6-year-old girl causing vaginal bleeding requiring transfusion. Vaginoscopy revealed a cervical IH of less than 1 cm. Expectant management and oral propranolol were successful management options.

Summary and Conclusion

Rare, even small soft tissue tumors such as IH can lead to impressive blood loss via vaginal bleeding. Accurate tissue diagnosis and a multidisciplinary approach are essential to planning safe, effective treatment, and follow-up.  相似文献   
102.
103.
Multisection, dual-echo magnetic resonance (MR) transaxial images of blood vessels contain both anatomic and qualitative information about flow. Even so, the images are produced as a series of two-dimensional tomographic sections from which full visualization of connected structures is difficult. A computer algorithm was developed that automatically detects flowing blood based on pixel intensity and calculated T2 and provides reconstructed views of vessels while analyzing and displaying flow characteristics. Images of abdominal vessels, aortic aneurysms, and the heart were encoded by flow and color to demonstrate depth. In addition, these data were reconstructed to derive a more accurate assessment of patency. With this technique, transaxial images can be used to analyze flow patterns, determine patent areas, and visualize all levels of vessels in a single image.  相似文献   
104.
Between 1989 and 2002, 178 renal transplants were performed in 168 pediatric patients in Chile. The mean age was 10.9 +/- 3.7 years (range 1 to 17.9). End-state renal disease etiologies were: congenital renal hypoplasia/dysplasia, chronic glomerulonephritis, and reflux nephropathy. Seventy received a graft from a living donor (LD), and 108 from a cadaveric donor (CD). Only 9% received antibody induction. Acute rejection episodes were reported in 76 patients: 38% in LD recipients and 48% in CD recipients (P = NS). One-, 3-, and 5-year graft survivals were 88%, 84%, and 76%, respectively, for LD and 86%, 79%, and 68% for CD recipients. Actuarial graft survival was significantly better among those patients with serum creatinine < 1 mg/dL at 1 year posttransplant compared with those with creatinine > 1 mg/dL (P < .05). The graft survival rate has improved from the first period (1989 to 1996) to the second period (1997 to 2002); (P = .05). Patient survival rates at 1, 3, and 5 years were 98%, 98%, and 98%, respectively, for LD, and 95%, 94%, and 94% for CD. Global height/age Z-score decreased from -0.7 at birth to -1.5 when dialysis started, and to -2.4 at the time of transplantation. The Z-score height/age at 1, 3, and 5 years posttransplantation was -2.25, -2.24, and -2.5. No significant differences were observed in transplant outcomes comparing patients younger than 7 years with those older ones. In conclusion, pediatric renal transplant has been performed in Chile with acceptable morbidity. The patient and graft survivals are similar to the reported international experience. In the last period there was a significant improvement in graft survival.  相似文献   
105.
106.
Focal epithelial hyperplasia (FEH) is a benign proliferation of the oral mucosa with well defined clinical and histological characteristics. It has been associated with infection of the oral mucosa by types 13 and 32 of the human papillomavirus (HPV), and to a lesser extent, with other types. Its clinical course is variable, although it usually persists for months or years; cases with spontaneous resolution have been described, as have others with prolonged persistence. We present the case of an Ecuadorian boy whose visit was motivated by lesions in the oral mucosa consistent with a diagnosis of FEH, which were confirmed in the histological study, and in which HPV type 13 DNA was identified.  相似文献   
107.
We report a 12-7/12 year-old male with obesity, eunuchoid proportions, genetic stigmata of Turner's syndrome and mild developmental delay. We investigated whether cytogenetic alterations could be responsible for his phenotype. Conventional karyotype in 70 peripheral blood cells was 45,X(15%)/46,XYqh-(85%). Dual FISH on 1,000 nuclei revealed 8% of X0 cells (DXZ1 X-centromeric probe) and 92% of XY cells (DYZ3 Y-centromeric probe). We studied Y chromosome microdeletions by PCR. The patient showed a terminal Yq deletion from the 5I interval including the AZFb and AZFc regions. FSH, LH and testosterone (468 ng/dl) were within the normal range for his age. At Tanner IV pubertal development the spermiogram showed azoospermia and the testicular aspirate spermatic arrest. The present report suggests that Y chromosome deletions including AZFb and AZFc regions may cause spermatogenic arrest in early puberty.  相似文献   
108.
Mucormycosis, a rare opportunistic infection caused by fungi belonging to the Mucorales order, is a potentially fatal disease. We describe 4 patients with mucormycosis. Risk factors (chronic renal insufficiency and chronic lung disease treated with corticosteroids) were identified for 2 of the patients who did not respond favorably to appropriate surgical and medical treatment. Of the 2 remaining patients, only the one with milder disease responded to treatment. The prognosis for this opportunistic infection, whose low incidence has increased in postoperative intensive care units, is very poor if early treatment is not given.  相似文献   
109.
Efficient systems for in vitro translation are of importance for biochemical and gene expression studies as well as for biotechnological developments. We optimized a cell-free translation system using subcellular fractions from human placenta and high quality placental tRNAs isolated using a simple and fast procedure. The postmitochondrial fraction or a reconstituted system containing soluble proteins plus polysomes were able to efficiently translate endogenous and exogenous mRNAs. Optima for ions, enzymes, tRNA and energy mix components were determined for a poly(U)-directed poly(Phe) synthesis test. The use of homologous tRNAPhe, omission of commercial creatine kinase, and addition of 3.5 mM spermidine at near physiological magnesium concentration (2.5 mM), were the most significant improvements. Under optimal conditions, poly(Phe) synthesis proceeded at a maximal initial rate of 1.2 Phe/80S/min at 37 degrees C, while natural mRNA translation by S-30 started at a near in vivo estimated rate of 0.3-0.5 amino acid/80S/sec. Furthermore, natural mRNA directed the synthesis of a family of polypeptides closely resembling the pattern of cytoplasmic proteins in both, molecular weight and relative amounts. This efficient and faithful system is of interest for biochemical studies of the human translational machinery, as well as a basis for screening new drugs affecting protein synthesis in pathogenic microorganisms.  相似文献   
110.
BACKGROUND: Evidence that sodium caseinate (CasNa) is capable of inhibiting proliferation of hematopoietic precursor cell line 32D and inducing its differentiation into macrophage cells has recently been published. Taking into consideration that hematopoiesis is regulated by growth factors and that macrophage colony-stimulating factor (M-CSF) is a well-known growth factor that induces differentiation of macrophages, in this work we evaluated whether CasNa is capable of inducing expression and secretion of M-CSF in 32D cells. METHODS: We cultured 32D cells in presence and absence of CasNa and compared their proliferation and viability. RNA was extracted from cell lysates to evaluate expression of the gene for M-CSF and its receptor. Cultured conditioned media was used to evaluate presence of M-CSF. RESULTS: Our results showed that CasNa inhibited proliferation of 32D cells and that conditioned media (CM) of these cultures contained M-CSF-like activity. Presence of M-CSF in CM was detected by inhibiting M-CSF activity with anti-M-CSF and presence of this growth factor was confirmed by ELISA assay. We also provided evidence that CasNa induced expression of mRNA for M-CSF in 32D cells as well as increased expression of mRNA for its receptor. CONCLUSIONS: CasNa inhibits proliferation of 32D cells and induces expression of the gene for M-CSF and that of its receptor. It also induces secretion of the bioactive form of M-CSF.  相似文献   
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