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1.
A cytomorphometric analysis of superficial vaginal cells inwomen in three groups of different types of hormonal concentrationwas made. There were 15 women in each group. Group I was studiedduring a natural cycle, group II under oral contraceptive therapyand group III during an in-vitro fertilization (IVF) stimulationprotocol. Morphometric parameters were measured on an imageanalyser. The area, perimeter and several form factors weremeasured separately for nuclei and cytoplasm. The nucleus:cytoplasmicratio was also determined. The cytoplasmic area was significantlyreduced in group II and was associated with a statisticallysignificant reduction of the nuclear area. The nucleus:cytoplasmicratio appeared significantly increased in group II and reducedin group III. Low oestradiol impregnation obtained with an oralminidosed contraceptive interfered with vaginal cell maturation.High oestradiol concentrations obtained during IVF protocolsinduced marked nuclear pycnosis but did not induce supra-physiologicalcell enlargement. Maximal cell size is genetically regulatedaccording to Driesch's law of volume invariance and hormonalover-stimulation has no effect on cell size. The nucleus:cytoplasmicratio appears to be a powerful parameter reflecting the oppositeeffects of hormones on cell compartments.  相似文献   
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Medifoxamine, an antidepressant agent which has an original chemical structure, has been shown through in vitro studies, utilising radioligand binding in tissue homogenates, to bind with moderately high affinity to 5-HT1c and 5-HT2 receptor subtypes and to 5-HT uptake sites (IC50 950, 980, and 1,500 nM, respectively). It has been shown to bind in vivo to rat brain 5-HT2 receptors after acute treatment with high dose (50 mg/kg, i.e., 133.9 μmol/kg). After 14 days continuous treatment with low dose (20 mg/kg, 53.6 μmol/kg), a decrease in the capacity of [3H]-5-HT uptake and a dose-dependent down-regulation of 5-HT2 receptors in rat cerebral cortex were observed. These results indicate that medifoxamine, which has been shown previously to act through dopaminergic systems, interacts also with central serotonergic neurotransmission and particularly with the 5-HT2 receptors, which could contribute to its antidepressant effect.  相似文献   
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The interaction between piperoxan and alpha 2-agonists on sympathetic tone was studied in rats. The sympatho-inhibitory effect of alpha 2-agonists (clonidine, guanfacine, B-HT 933) was assessed by recording heart rate in normotensive bilaterally-vagotomized rats. Clonidine (3 micrograms/kg, i.c.v.) and B-HT 933 (100 micrograms/kg, i.c.v.) induced a bradycardia which was fully reversed by piperoxan (30 micrograms/kg, i.c.v.). However, in rats treated with guanfacine, piperoxan induced a partial recovery of the bradycardic effect. The injection of a small dose of the specific alpha 1-adrenoceptor blocking drug, AR-C 239 (10 micrograms/kg, i.c.v.) which, by itself did not modify heart rate, completely inhibited the reversal effect of piperoxan in rats treated with clonidine, B-HT 933 or guanfacine. In rat brainstem membranes, B-HT 933 was found to bind to both alpha 1- and alpha 2-adrenoceptors and was as potent as clonidine in competing for alpha 1-sites bound by [3H]prazosin. On the other hand, in bilaterally vagotomized rats, piperoxan (30 micrograms/kg, i.c.v.) induced an increase in blood pressure and heart rate which was inhibited by previous administration of AR-C 239 (10 micrograms/kg, i.c.v.). These data suggest that, by inhibiting central alpha 2-adrenoceptors, piperoxan unmasks central alpha 1-adrenoceptor stimulation by endogenous catecholamines leading to an increase in the sympathetic tone, but a full recovery in heart rate could be observed only with the mixed alpha 1- and alpha 2-adrenoceptor agonists, clonidine and B-HT 933. In addition, these data further indicate that alpha 1-adrenoceptors are implicated in a tonic control of the sympathetic nerve activity in normotensive rats.  相似文献   
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For the past few years, a new method for the investigation and treatment of arrhythmias has been used: transoesophageal atrial pacing and recording (TAPR). In the light of 6 cases observed recently, we review the technical aspects and the indications for TAPR. A bipolar stimulation catheter is inserted in the oesophagus and positioned in the area where the atrial wave of greater amplitude is recorded. Atrial stimulation is done with impulses of long duration obtained with a special stimulator. Two cases validated this technique which was effective to correct atrial flutter in a neonate with heart failure resistant to medical treatment as well as in a 5 year-old child. The value of TAPR as a diagnostic tool in cases of tachycardia is discussed in the context of 2 cases: a 5 week-old with wide QRS and a 14 month-old with narrow QRS. Finally, the value of TAPR for monitoring the efficacy of anti-arrhythmia medications is illustrated by 4 cases of supraventricular tachycardia, in whom the optimal dosage of the anti-arrhythmic drug used was determined with the help of TAPR-induced tachycardia. The current literature concerning the technique, indications and results of TAPR are reviewed. This method is likely to take a great importance for the study and treatment of supraventricular arrhythmias in children.  相似文献   
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OBJECTIVE: To assess the extent of nosocomial transmission of tuberculosis among infants, family members, and healthcare workers (HCWs) who were exposed to a 29-week-old premature infant with congenital tuberculosis, diagnosed at 102 days of age. DESIGN: A prospective exposure investigation using tuberculin skin test (IST conversion was conducted. Contacts underwent two skin tests 10 to 12 weeks apart. Clinical examination and chest radiographs were performed to rule out disease. Isoniazid prophylaxis was administered to exposed infants at higher risk. SETTING: A neonatal intensive care unit in an urban hospital in Brussels, Belgium. PARTICIPANTS: Ninety-seven infants, 139 HCWs, and 180 visitors. RESULTS: Newly positive TST results occurred in HCWs who had been in close contact with the infant. Six (19%) of 32 primary care nurses and physicians had TST conversions and received treatment. Among the 97 exposed infants, 85 were screened and 34 were identified as at higher risk of infection. Of these, 27 received preventive isoniazid. None of the infants and none of the 93 other infants' family members evaluated were infected. CONCLUSIONS: Congenital tuberculosis in an infant poses a risk for nosocomial transmission to HCWs. Delayed diagnosis of this rare disease and close proximity are the most important factors related to transmission.  相似文献   
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A retrospective review of 56 patients operated upon for tumours of Oddi was performed in order to determine optimal diagnostic and therapeutic procedures. Common presenting symptoms were jaundice (86%) and anemia (21%). Mean size of the tumour was 2.3 cm. Five tumours were benign and 51 were malignant. According to the classification of Martin, five were grade I: 10 grade II; 18 grade III; and 18 grade IV. Forty-seven patients underwent resection of the tumour: three local excisions for small benign tumors, six ampullectomies (followed in three by a Whipples’ procedure for recurrence) and 41 Whipples’ procedures. The hospital mortality was 5.3%, minor complications appeared in 21%. The overall five years survival was 41%. It was 75% in grade I, 50% in grade II, 40% in grade III and 10% in grade IV. The patients who received ampullectomies were alive with a follow-up of one, two and three years. All patients operated upon for a benign tumour were alive except one who died of cardiac failure. Ultrasonography and duodenoscopy are the most useful tests for the diagnosis of tumours of Oddi. Prognosis depends on the degree of infiltration of the duodenal wall and the presence of positive lymph nodes. Whipples’ procedure is best but ampullectomy can be used in elderly or poor risk patients. Malignant tumours of the ampullary region are infrequent and reported to constitute betwee 0.02 and five percent of all cancers of the digestive tract. With wider application of endoscopic techniques, there has been an increasing interest in this group of tumours during recent years. In the literature tumours of Oddi are usually reported in the group of periampullary tumours, including tumours of the ampulla itself, duodenal wall surrounding the ampulla, the distal part of the common bile duct and head of the pancreas. We have wanted to distinguish specifically the tumours of the ampulla of Vater and have adopted the term tumour of Oddi introduced by Marchal and Hureau.The sphincter of Oddi exactly delineates the junction between the bile duct, pancreatic duct and duodenum. We wanted to avoid using the anatomic term ampulla of Vater, since this structure rarely appears as an ampulla. This then excludes tumours in the head of pancreas, common bile duct above ths phincter of Oddi and tumours of the duodenal wall adjacent to the papilla. These tumours seem to behave differently from other pancreatic tumours, as they carry a different prognosis and need special attention. We have therefore reviewed retrospectively 56 patients with tumours of Oddi with special reference to diagnosis, histopathologic examination and surgical therapy.  相似文献   
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Epidermal growth factor excretion in burned rats   总被引:3,自引:0,他引:3  
Evidence for epidermal growth factor (EGF) involvement in the physiological response to burns was sought from urinary levels of EGF, urea and creatinine in male rats using a standardized thermal skin injury model (25 per cent body surface) and treated with fluid resuscitation. Postmortem, the skin lesions were studied by microscopy to guarantee the absence of inflammatory complications. Statistically significant differences were observed in body weight, urea and creatinine excretion when compared to the basal values. When EGF excretion results were evaluated as raw data (expressed as ng/mg of creatinine or ng/day) compared to basal levels, no statistically significant differences were observed. However, when the results were expressed as percentage increases with respect to the basal values, a statistically significant increase was found over the first 7 days postinjury (P = 0.029).  相似文献   
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