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991.
PURPOSE: To describe the clinic-pathological analysis of the visually significant opacification of the Cirrus International Hydroflex foldable hydrophilic acrylic intraocular lens (IOL) (model SC600-2, Medical Developmental Research Inc., Clearwater, Florida) and to highlight that this IOL is the same model as the Acryflex SC600-2 IOL, by the same manufacturer. METHODS: Retrospective review of five eyes of four patients with opacification of their Cirrus International Hydroflex foldable hydrophilic acrylic IOLs (model SC600-2) after uncomplicated phacoemulsification and IOL implantation. Two IOLs were explanted from two patients 14 to 24 months after initial implantation. Each explanted lens was divided into equal halves, one half for scanning electron microscopy (SEM) study and the other half for transmission electron microscopy (TEM) examination. SEM and TEM samples were also subjected to energy dispersive X-ray analysis (EDX). RESULTS: The IOL opacification was detected 14 to 24 months after uncomplicated phacoemulsification and IOL implantation. EDX analysis showed that the crystals contained calcium and phosphorus, presumably calcium phosphate. CONCLUSIONS: The Cirrus International Hydroflex foldable hydrophilic acrylic IOL (model SC600-2) is associated with opacification, that appeared worse centrally than peripherally. This is the same model as the Acryflex SC600-2 IOL, made by the same manufacturer. The opacification consists of calcium and phosphate.  相似文献   
992.
993.
An orbital embryonal rhabdomyosarcoma, which was excised from the orbit of an 8-year-old girl, was studied by light microscopy and transmission electron microscopy. Cells within the tumour demonstrated by light microscopy diffuse areas of necrosis and isolated single-cell necrosis. There were many viable tumour cells with intracytoplasmic vacuolar structures which contained basophilic granules. Ultrastructural studies showed close apposition between well-preserved tumour rhabdomyoblasts and degenerate or necrotic tumour cells: degenerate cells and condensed cell fragments were observed within the cytoplasm of the well-preserved tumour cells. Some cells which showed degenerative changes had features which suggested that they had ingested more than one degenerate cell on separate occasions. This phenomenon may be regarded as a variant of selective individual cell death, currently referred to as apoptosis, which has not been previously reported in a case of embryonal rhabdomyosarcoma. The patient remains free of tumour recurrence four years following treatment with combined radiotherapy and chemotherapy.  相似文献   
994.
Fine-needle aspiration of the breast has become a well-accepted diagnostic tool for the management of breast lesions. When employed on an ambulatory basis it is both accurate and cost-effective. This study of a series of patients managed over a 2-year period demonstrates the use of this technique in an ambulatory gynecologic practice. Results demonstrate this to be a very rapidly accomplished, effective procedure that is very well accepted by the patients. Results are generally available within 24 hours and permit both the physician and the patient to accurately predict the course of management. In addition, it allows the primary physician to accurately determine which patients will require in-hospital management and which may safely undergo ambulatory, office-based biopsy of solid lesions. Experience shows this to be a valuable diagnostic tool that can be safely utilized by the practicing gynecologist.  相似文献   
995.
Seven oliguric women with preeclampsia were identified among patients admitted for obstetric care at Jefferson Davis or Hermann Hospitals in Houston, Texas. Urinary diagnostic indices (including urine-to-plasma ratios of creatinine, urea nitrogen, and osmolality) were generally consistent with a prerenal etiology for the observed oliguria. Conversely, invasive hemodynamic monitoring revealed a volume replete state in five of seven preeclamptic women studied. All patients were observed to have markedly elevated urinary sodium concentrations. The transient oliguria observed in these patients spontaneously resolved without diuretic or hyperosmolar agents. We conclude that oliguria is a poor index of volume status in preeclamptic women. Urinary diagnostic indices may also be misleading if used to guide fluid management in these patients. Finally, the clinical significance and therapeutic alternatives relating to preeclampsia-associated oliguria are discussed.  相似文献   
996.
Natural killer (NK) cells have the ability to kill a variety of target cell types and the possibility that such cells could mount an effective attack on the developing fetus has not been discounted. The present study extends previous work showing that maternal NK reactivity against K562 target cells (TC) is reduced during pregnancy. Here we demonstrate using cytotoxicity assays at both the population and single cell level that, although depressed in number, maternal NK cells exhibiting the capacity to kill K562 TC are as lytically active in their ability to recycle and destroy multiple TC as NK cells from non-pregnant females. Moreover, two colour immunofluorescence analysis of the NK cell-associated markers Leu-7 and Leu-11b indicates that, in addition to a reduction in the absolute number of TC conjugate-forming cells, pregnant females present in their peripheral blood a larger proportion of TC-binding Leu-7+11- cells. These cells may be lytically immature. Small changes in NK cell profile and activity in maternal peripheral blood may be indicative of much more significant changes at the feto-maternal interface. It is, however, clear that pregnant females retain a population of highly active NK cells, thus minimising the possibility of immunocompromise.  相似文献   
997.
Over a 1-year period, seven eclamptic patients with repetitive seizures while receiving therapeutic levels of intravenous magnesium sulfate were evaluated by computerized axial tomography. In five patients brain abnormalities were identified, which included diffuse cerebral edema (one), cerebral venous thrombosis (two), and low density white matter (two). Clinical management of eclamptic women on the basis of structural central nervous system abnormalities documented by computerized tomography appears to warrant further investigation.  相似文献   
998.
The antemortem diagnosis of amniotic fluid embolism has traditionally relied on the identification of amniotic fluid debris in the maternal circulation by central venous or pulmonary arterial catheterization. Pulmonary artery blood specimens from 14 term pregnant women with severe pregnancy-induced hypertension suggest that squamous or trophoblastic cells may be normally present in the maternal pulmonary circulation during the peripartum period and that their presence is not pathognomonic of clinically significant amniotic fluid embolism.  相似文献   
999.
Two hundred eighteen patients underwent urinary diversion: 156 with ileal and 62 with sigmoid conduits. There were no significant differences between the two groups regarding frequency of conduit morbidity or patient survival. The ileal conduit is preferred for urinary diversion with anterior exenteration, whereas the sigmoid conduit is preferable for urinary diversion with total exenteration.  相似文献   
1000.
The evaluation of comparative pregnancy data in clinical studies is subject to a variety of biases. One such bias, when treated patients are retrospectively compared with untreated control subjects, results from the fact that treated patients must remain infertile from time of diagnosis to time of treatment while no such requirements is maintained for untreated control subjects. This bias is also apparent when patients undergo sequential treatments and transfer from one comparison group to another. We have eliminated this problem by applying the Mantel-Byar approach for constructing and comparing modified life tables that reflect sequential changes of treatment status. To illustrate this we applied commonly used methods of analysis as well as the Mantel-Byar method to infertile endometriosis patients attempting pregnancy. One hundred thirty consecutive patients were evaluated retrospectively, with 42 undergoing expectant management only, seven experiencing a conservative surgical procedure only, and 81 having a conservative surgical procedure after a variable period of expectant management. Use of Mantel-Byar analysis revealed no significant overall increase in pregnancy rate with conservative surgical procedures versus expectant management (chi 2 = 0.225, df = 1). To further assess the potential value of conservative surgical procedures in fertility enhancement, the data were stratified by degree of endometriosis. The adjusted chi 2 was 1.621. No significant difference was noted between the two therapeutic approaches with mild disease (n = 35, chi 2 = 0.0175) or moderate endometriosis (n = 59, chi 2 = 0.424). Conservative surgical procedures appear to be therapeutic, however, in women with severe disease (n = 36, chi 2 = 5.12, p less than 0.05). These results differed substantially from those obtained with the more biased analytic methods routinely used in clinical fertility trials. This study illustrates the utility of the Mantel-Byar approach as a valuable tool in the evaluation of response time data involving transient therapeutic states and one particularly adaptable to retrospective infertility studies involving sequential treatment approaches.  相似文献   
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