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41.
OBJECTIVE: To determine the effect of various freezing protocols on postthaw development and pregnancy rates resulting from transfer of human zygotes. DESIGN: Prospective study. SETTING: Tertiary care center. PATIENT(S): Couples undergoing assisted reproductive technology (ART) procedures who wished to have their excess zygotes cryopreserved. INTERVENTION(S): We cryopreserved zygotes with one of three protocols. MAIN OUTCOME MEASURE(S): Post-thaw survival and development of the zygotes as well as pregnancy rate after transfer of these zygotes. RESULT(S): A 3-minute hold time after seeding, followed by a final preplunging temperature of -180 degrees C, resulted in a clinical pregnancy rate of 28.6%. In contrast, a 15-minute postseed hold time and a -30 degrees C final chamber temperature resulted in a 37.3% clinical pregnancy rate. When we combined the protocols to provide a 15-minute postseed holding time and a -180 degrees C before plunging into liquid nitrogen, we achieved a 69.6% clinical pregnancy rate. CONCLUSION(S): By increasing the postseeding hold time and decreasing the temperature of the freezing chamber before plunging the zygotes into liquid nitrogen, significant improvements can be made in postthaw development and pregnancy rates.  相似文献   
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In 224 patients, renal stones were removed from the urinary tract using either direct extraction with a basket or forceps (59 patients), ultrasonic lithotripsy (164 patients), or infusion chemotherapy (one patient). Residual stone fragments were present more frequently in patients treated with ultrasonic lithotripsy (27%) than with direct extraction (5%). Other complications included hemorrhage (eight patients), catheter dislodgement (four patients), large amounts of urine extravasation (three patients), glycine ascites (three patients), infection (two patients), pneumothorax (one patient), and a prolonged ileus (one patient). More complications occurred among the first 50 patients than the last 50 patients, even though more difficult cases, including patients with staghorn calculi, were accepted during the latter period. Although a learning curve exists, complications can be minimized by attempting to treat more favorable cases during the initial experience.  相似文献   
43.
Treatment of oncologic emergencies   总被引:1,自引:0,他引:1  
Most oncologic emergencies can be classified as metabolic, hematologic, structural, or side effects from chemotherapy agents. Tumor lysis syndrome is a metabolic emergency that presents as severe electrolyte abnormalities. The condition is treated with allopurinol or urate oxidase to lower uric acid levels. Hypercalcemia of malignancy is treated with aggressive rehydration, furosemide, and intravenous bisphosphonates. Syndrome of inappropriate antidiuretic hormone should be suspected if a patient with cancer presents with normovolemic hyponatremia. This metabolic condition usually is treated with fluid restriction and furosemide. Febrile neutropenia is a hematologic emergency that usually requires inpatient therapy with broad-spectrum antibiotics, although outpatient therapy may be appropriate for low-risk patients. Hyperviscosity syndrome usually is associated with Waldenstr?m's macroglobulinemia, which is treated with plasmapheresis and chemotherapy. Structural oncologic emergencies are caused by direct compression of nontumor structures or by metastatic disease. Superior vena cava syndrome presents as neck or facial swelling and development of collateral venous circulation. Treatment options include chemotherapy, radiation, and intravenous stenting. Epidural spinal cord compression can be treated with dexamethasone, radiation, or surgery. Malignant pericardial effusion, which often is undiagnosed in cancer patients, can be treated with pericardiocentesis or a pericardial window procedure.  相似文献   
44.
Pneumonia caused by Staphylococcus aureus is a growing concern in the health care community. We hypothesized that characterization of the early innate immune response to bacteria in the lungs would provide insight into the mechanisms used by the host to protect itself from infection. An adult mouse model of Staphylococcus aureus pneumonia was utilized to define the early events in the innate immune response and to assess the changes in the airway proteome during the first 6 h of pneumonia. S. aureus actively replicated in the lungs of mice inoculated intranasally under anesthesia to cause significant morbidity and mortality. By 6 h postinoculation, the release of proinflammatory cytokines caused effective recruitment of neutrophils to the airway. Neutrophil influx, loss of alveolar architecture, and consolidated pneumonia were observed histologically 6 h postinoculation. Bronchoalveolar lavage fluids from mice inoculated with phosphate-buffered saline (PBS) or S. aureus were depleted of overabundant proteins and subjected to strong cation exchange fractionation followed by liquid chromatography and tandem mass spectrometry to identify the proteins present in the airway. No significant changes in response to PBS inoculation or 30 min following S. aureus inoculation were observed. However, a dramatic increase in extracellular proteins was observed 6 h postinoculation with S. aureus, with the increase dominated by inflammatory and coagulation proteins. The data presented here provide a comprehensive evaluation of the rapid and vigorous innate immune response mounted in the host airway during the earliest stages of S. aureus pneumonia.  相似文献   
45.
To determine the optimal dose of gamma radiation necessary to inhibit T- lymphocyte function and prevent transfusion-acquired graft-versus-host disease (TA-GVHD), a donor plateletpheresis component was initially divided into ten 20-mL samples. One sample was not irradiated, while the other nine samples were treated with gamma radiation at doses ranging from 500 to 4500 cGy. T-lymphocyte function was subsequently measured by mixed lymphocyte cultures and mitogen stimulation assays. The results were assessed in each test by calculating the percentage of inhibition of each irradiated sample as compared to that of the unirradiated sample. The accuracy of the delivered dose of gamma radiation was measured with thermoluminescent dosimeters. It was concluded that a nominal dose of 3000 cGy (actual dose delivered, 2898 cGy) is the appropriate amount of gamma radiation needed to eliminate T- lymphocyte-mediated graft-versus-host disease.  相似文献   
46.
Irradiation of the prostate, delivered as external beam radiation therapy (EBRT), is currently one of the few treatment options for localized prostate cancer. While it is relatively effective, the failure rate still remains unacceptably high with a 5-year biochemical failure rate of 10-40%. Utilizing genetically engineered LNCaP prostate cancer sublines that either overexpress Bcl2 (LNCaP/S22-d) or have down-regulated Bcl2 (LNCaP/AS17-f) we investigated the influence of this antiapoptotic protein on clonogenic survival following radiation. The radiation dose response curves (2-8 Gy) for the sublines differed significantly from the parental LNCaP (LNCaP/S22d: p < 0.001 and LNCaP/AS17-f: p = 0.008). The relative survival of the sublines revealed increased survival in the Bcl2 overexpressing cells, and decreased survival in the Bcl2 down-regulated cells. These data suggest a potentially important therapeutic approach for enhancing radiosensitivity in prostate tumors via antisense oligonucleotide or other drug therapies that down-regulate Bcl2. Strategies such as these likely hold the promise of enhancing the efficacy of EBRT by decreasing tumor cell survival, reducing the incidence of tumor recurrence and improving patient outcome.  相似文献   
47.

Purpose

To evaluate bropirimine for in vivo activity in rodent prostate cancer.

Materials and Methods

Subcutaneously injected PAIII and Dunning MAT-LyLu rodent prostate cancer cells caused solid tumors and death in controls. Bropirimine was given on varying schedules at 250 mg./kg. by gavage, and tumor volume and survival were recorded.

Results

Bropirimine prevented growth when given on the day of tumor injection and caused 95 percent of advanced tumors to regress completely in the PAIII model. Bropirimine caused significant growth inhibition and prolongation of survival in the MAT-LyLu model.

Conclusions

Bropirimine has statistically significant in vivo activity against both of these rodent prostate cancer cell lines.  相似文献   
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