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41.
Sodium balance was studied in 7 and 16 week old male spontaneously hypertensive rats (SHR), in matched normotensive Wistar rats (NCR) and in Wistar Kyoto rats (WKR). The animals were placed in metabolic cages and given diets with either normal sodium content (5.35 mmol sodium/100 g food) or with a sodium content 3 or 10 times the normal. Whether on normal or increased sodium diet we did not observe any increased sodium retention in either SHR age group. However, in both SHR groups urinary sodium excretion was significantly decreased, while faecal sodium excretion was correspondingly increased compared with the controls. This shift of sodium excretion from kidneys to gastrointestinal tract in SHR did not reflect any ‘primary’ inability of the SHR kidneys to excrete sufficient sodium amounts since on high sodium diet they excreted the increased sodium load as readily as the normotensive controls. The present results do not support the concept that a primary renal retention of sodium and water should be of pathogenetic importance for the SHR variant of primary hypertension.  相似文献   
42.
ABSTRACT. This study was conducted in order to test the usefulness of measuring the concentrations of selected serum proteins and acute phase reactants in assessing the nutritional status of children with undue susceptibility to acute infections. The concentrations of serum proteins were determined by an immunodiffusion technique in 28 children with undue susceptibility to infections and were compared with those in healthy children. The patients were grouped according to the clinical pattern, i.e. into children with mainly upper respiratory tract infections, with frequent middle ear infections and with lower respiratory tract infections. The total group and all three subgroups of patients had not only significantly lower ( p < 0.001 or p < 0.01) mean serum levels of albumin and retinol-binding protein, but also of the acute phase reactants α2-macroglobulin and ceruloplasmin ( p < 0.01) than the controls. No differences were observed between the patients and the controls in respect of the acute phase reactant orosomucoid. This study indicates that the concentrations of albumin and RBP along with selected acute phase reactants are rapidly influenced by altered nutritional status in children with undue susceptibility to acute infections.  相似文献   
43.
ABSTRACT. The outcome of all deliveries in Sweden in 1981 has been studied. The occupation of each mother was obtained by record linkage using census data from November 1980. Rates of perinatal deaths or congenital malformations did not vary according to maternal occupation, more than might be expected to happen by chance, which indicated that maternal occupation is not a major factor in the outcome of these deliveries. There was variation in the rates of low birth weight infants, according to maternal occupation, which may have been an effect of socioeconomic factors associated with the occupation. Within occupational groups, working situations may exist which entail an increased teratogenic risk, but in order to reveal such risks, studies with a different design must be carried out.  相似文献   
44.
Abstract – Twelve patients with subjective symptoms, ascribed by the patients themselves to mercury released from dental restorations, were investigated. In addition to a general dental examination the following parameters were registered: the total number of amalgam surfaces in the mouth; potential and polarization of existing and accessible dental metallic restorations for calculation of intraoral currents. As regards the highest calculated intraoral current for each individual there was a statistically significant difference between the patient group and a control group consisting of 12 persons. An analysis of the amount of selenium, glutathione-peroxidase and mercury in the blood showed no differences between the patient and the control group. However, a statistically significant positive correlation could be seen between the total number of amalgam surfaces and the plasma-mercury level for patients and controls pooled together. The numerous other blood parameters analyzed did not reveal any differences between the groups.  相似文献   
45.
ABSTRACT It is generally believed that prostacyclin (PGI2) generation is greatly stimulated when blood vessels are injured, even by minor trauma, such as venepuncture. The Simplate technique for measuring skin bleeding time was adapted to quantify by radioimmunoassay PGI2 and thromboxane A2 (TXA2) in the emerging blood, as the stable degradation products 6-keto-prostaglandin F (6-keto-PGF) and thromboxane B2 (TXB2), both of which were measured in venous plasma as well as in serum (clotted at 37°C for 1 h). During bleeding, when platelets aggregate to occlude the injured vessels, the median TXB2 level in the emerging bleeding time blood was 1.7 ng/ml. The median TXB2 level in plasma was < 1 ng/ml and in serum 275 ng/ml. The levels of immunoreactive 6-keto-PGF were always below determination limit in bleeding time blood (0.2 ng/ml) and in plasma (0.1 ng/ml), whereas in serum the levels ranged between 0.26 and 0.47 ng/ml. The fact that enhanced PGI2 production in primary haemostasis in skin incisions could not be demonstrated calls for further investigations of possible PGI2 production with more sensitive assays or in injured large vessels.  相似文献   
46.
abstract – Biopsy specimens from the temporalis or masseter muscles of 12 subjects were studied by histochemical means. The fiber sizes in the masticatory muscles were compared with those of the biceps brachii muscle in 4 females. On the basis of staining reactions for ATPase, two fiber types, Type I (low ATPase activity) and Type II (high ATPase activity), were demonstrated. In the masticatory muscles the Type II fibers generally dominated in number and were smaller in diameter than Type I fibers. Both fiber types had smaller diameters than corresponding fiber types of biceps brachii.  相似文献   
47.
ABSTRACT – Biopsy specimens from temporal muscle of denture wearers and subjects with natural dentition were studied by biochemical staining methods. Size and distribution of fiber types were estimated in sections stained for myofibrillar ATPase at pH 9.4. The mean sizes of Type 1, * Type 2 and intermediate fibers in denture wearers did not differ from those of the corresponding types of fibers in subjects with natural dentition. In the denture series. Type 2 fibers were smaller in subjects who rated their dentures as deficient than they were in those whose dentures were good. The frequency of intermediate fibers was low in both series. The mean percentage distribution of Type 2 fibers in specimens from the internal surface of the temporal muscle was significantly lower in the denture series than in the specimens from subjects with natural dentition. It is suggested that the low content of Type 2 fibers in the specimens from the internal surface of the temporal muscle of denture wearers and the small size of Type 2 fibers in subjects who rated their dentures as deficient may be attributed to altered functional demands.  相似文献   
48.
49.
Abstract. In search of new practical diagnostic methods for the early diagnosis of hereditary medullary carcinoma of the thyroid (MCT) calcitonin release has been studied following induction by pentagastrin, cholecystokinin-pancreozymin (the C-terminal octapeptide, C8-CCK, and the native swine extract), and ethanol in eighteen cases of MCT (all but one clinically occult), three ‘borderline cases’, seven first degree relatives of patients with hereditary MCT and thirty-five healthy controls. Pentagastrin, subcutaneous (s.c.) or intravenous (i.v.), induced a pronounced and rapid increase of serum calcitonin within 2–5 min. The elevation was roughly proportional to the tumour mass as estimated at operation. Seventeen out of eighteen MCT patients responded to s.c. pentagastrin with a significant increase in serum calcitonin and the response correlated well with that induced by calcium infusion test. Only two blood samples, at times 0 and 5 min, were necessary for diagnosis. In the MCT patients, i.v. pentagastrin produced more pronounced elevations of serum calcitonin than did s.c. pentagastrin, whereas no increase was seen in the control group. The subjective discomfort caused by i.v. pentagastrin was somewhat more intense but lasted shorter than that induced by s.c. administration. No serious complications were seen. All of nine MCT patients responded to C8-CCK with increments in serum calcitonin exceeding those of the control group and both of two responded similarly to the native cholecystokinin-pancreozymin extract. Generally the serum calcitonin response was lower and more variable after C8-CCK than after s.c. or i.v. pentagastrin, and the subjective discomfort was also more pronounced with abdominal cramps during the injection. Ethanol in the dose used was the least effective stimulator for serum calcitonin release. Clinically suspected MCT carriers with palpable tumours can be diagnosed by determination of the basal, i.e. non-stimulated serum calcitonin levels. Other possible Sipple genome carriers, who are at the time clinically healthy with normal basal serum calcitonin, should be subjected to a s.c. or i.v. pentagastrin stimulation test at each examination. These tests are much simpler to perform than a calcium infusion test, but seem to have about the same sensitivity.  相似文献   
50.
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