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71.
Postembolic colonic infarction   总被引:12,自引:0,他引:12  
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OBJECTIVES: Surgical resection after preoperative chemotherapy in patients with non-small cell lung cancer might only be best for patients who are responders. We compared positron emission tomographic scanning with 2-fluoro-2-deoxy-d-glucose (FDP-PET scanning) with computed tomographic scanning to evaluate their ability to predict this response for the primary tumor, N1 and N2 lymph nodes. METHODS: All patients with non-small cell lung cancer who had an initial FDP-PET scan staging with tissue biopsy, neoadjuvant chemotherapy, repeat FDP-PET scanning, and repeat biopsies were prospectively studied. RESULTS: There were 34 patients (24 men; median age, 64 years). Eleven patients had N2 disease, and 7 had N1 disease. Twenty-seven patients received chemotherapy, and 7 patients received chemotherapy and radiation. All but 9 patients underwent resection. Statistical analysis showed FDP-PET scanning to be more specific (P <.0001), to have a higher positive predictive value (P =.0018), and to have a higher negative predictive value (P <.0001) than computed tomographic scanning for predicting residual tumor at the primary site. FDP-PET scanning was more sensitive (P <.0001) and more accurate (P <.0001), had a higher positive predictive value (P <.0001), and had a higher negative predictive value (P =.0002) than computed tomographic scanning for paratracheal nodes (number 2 and 4 lymph nodes). FDP-PET scanning had a higher positive predictive value (P <.0001) than computed tomographic scanning for the other N2 (numbers 5, 6, 7, 8, and 9) lymph nodes. CONCLUSIONS: Repeat FDP-PET scanning is more specific and has a higher positive predictive value and negative predictive value than computed tomographic scanning for detecting residual tumor in the lung in patients with non-small cell lung cancer who have received preoperative chemotherapy. It is more sensitive and accurate for paratracheal N2 nodes as well. However, there is no significant difference in its detection of N1 lymph nodes.  相似文献   
74.
1. Infusion experiments were performed on chronically catheterized conscious rats to assess kidney function before and after the induction of diabetes mellitus with streptozotocin. 2. Two infusion regimens were used, a conventional constant-infusion protocol and a novel computer-driven, servo-controlled fluid replacement technique. The latter enables body fluid status to be maintained throughout a study occasion by servo-controlled replacement of spontaneous urinary fluid losses. 3. The chronically catheterized conscious rat infused using a servo-controlled system appears to be the optimum model for a study of diabetic renal function. The conscious preparation circumvents problems associated with anaesthesia and acute surgery. The servo-controlled infusion protocol maintains the altered fluid status of the diabetic condition. Both hyperfiltration and polyuria, characteristics of human diabetes often absent in anaesthetized and/or constantly infused diabetic rats, were seen in all conscious servo-controlled diabetic animals. 4. The new regimen enables a more accurate assessment of renal function in experimental diabetes than with previous protocols. It should prove useful in future studies, particularly those assessing the role of anti-diabetic drugs on the kidney.  相似文献   
75.
A family is described in which 2 siblings born to healthy parents presented with abnormal facies, persistent diarrhoea, and early death. Exhaustive pathological and biochemical investigations failed to find a cause. The scalp hair of both babies had an abnormal amino-acid composition, and presented an appearance that was unique on scanning electron microscopical examination; this fact and the clinical picture probably represents a new syndrome.  相似文献   
76.
In order to test the hypothesis that integrin and uteroglobin (UG) expression in cultured endometrial cells are affected by hormone treatment, Ishikawa-CH endometrial cancer cells were cultured and exposed to oestradiol or oestradiol and progesterone regimens and assayed using immunohistochemistry. We evaluated the intensity of immunohistochemical staining for the integrin monomers alpha(v) and beta1, the dimers alpha(v)beta3 and alpha(v)beta6, and for the secretory protein uteroglobin under various experimental conditions. Cells grown in control media stained positively for the integrin monomers alpha(v) and beta1, the dimer alpha(v)beta3, and for UG. Oestradiol and sequential oestradiol/progesterone reversibly suppressed staining for the dimer alpha(v)beta3. Hormone treatment had no effect on the staining of the beta1 and alpha(v) monomers or UG. The alpha(v)beta6 dimer antibody did not stain under any experimental treatment conditions. These data indicate that expression of the integrin complex alpha(v)beta3 is reversibly suppressed by oestradiol in Ishikawa cells and that these cells may be a good model for studying hormone-driven molecular changes in endometrium.   相似文献   
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Dunn  EK; Macchia  RJ; Solomon  NA 《Radiology》1981,139(1):175-180
The testicular scintigraphic findings of nine patients with surgically and pathologically proved torsion of the testis of over 24 hours duration are reviewed. In the delayed blood-pool images each showed the classical avascular twisted testicle with a variable peripheral rim of hyperemia. In the dynamic blood-flow phase, eight revealed a perceptible increase of vascular perfusion in the scrotal region on the affected side, in addition to the testicular radionuclide angiogram peculiarities previously described for missed testicular torsion. This pattern of perfusion was seen only in torsion of over one day duration. A low salvage probability is expected in these cases.  相似文献   
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Objectives: To assess the influence of clinical status on the association between total plasma bilirubin and unbound bilirubin on death or adverse neurodevelopmental outcomes at 18–22 months corrected age in extremely low birth weight infants. Method: Total plasma bilirubin and unbound bilirubin were measured in 1101 extremely low birth weight infants at 5 ± 1 days of age. Clinical criteria were used to classify infants as clinically stable or unstable. Survivors were examined at 18–22 months corrected age by certified examiners. Outcome variables were death or neurodevelopmental impairment, death or cerebral palsy, death or hearing loss, and death prior to follow‐up. For all outcomes, the interaction between bilirubin variables and clinical status was assessed in logistic regression analyses adjusted for multiple risk factors. Results: Regardless of clinical status, an increasing level of unbound bilirubin was associated with higher rates of death or neurodevelopmental impairment, death or cerebral palsy, death or hearing loss and death before follow‐up. Total plasma bilirubin values were directly associated with death or neurodevelopmental impairment, death or cerebral palsy, death or hearing loss, and death before follow‐up in unstable infants, but not in stable infants. An inverse association between total plasma bilirubin and death or cerebral palsy was found in stable infants. Conclusions: In extremely low birth weight infants, clinical status at 5 days of age affects the association between total plasma bilirubin and death or adverse neurodevelopmental outcomes at 18–22 months of corrected age. An increasing level of UB is associated a higher risk of death or adverse neurodevelopmental outcomes regardless of clinical status. Increasing levels of total plasma bilirubin are directly associated with increasing risk of death or adverse neurodevelopmental outcomes in unstable, but not in stable infants.  相似文献   
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