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1.
Seishi Inoue Tadayasu Shono Mieko Shono Masayuki Azuma Toshiaki Hirabayashi Oshi Inagaki Hidetaro Mori Yoshikazu Fujita 《Journal of bone and mineral metabolism》1990,8(3):19-23
A case of polycythemia vera complicated by chronic renal failure under maintenance hemodialysis requiring parathyroidectory
(PTH) for secondary hyperparathyroidism (2° HPT) is reported.
A 62 year old female presented with 75000 white blood cells (WBC)/μl, 703×104 red blood cells (RBC)/μl, 23×104 platelets (PLT)/μl, hyperuricemia and hypertension in 1970 and the diagnosis of polycythemia vera was made. Hemodialysis
was started in October 1974 for chronic renal failure. Blood cells in peripheral blood rapidly decreased in number after the
beginning of dialysis, reaching the level of 10000∼20000 WBC/μl, and 150∼250×104RBC/μl. In August 1988, marked bone resorption in X-ray picture and high serum alkaline phosphatase and parathyroid hormone
(PTH) noted along with 17400 WBC/μl, 370×104RBC/μl and 35.9×104PLT/μl.
After subtotal PTX removing 3.21g parathyroid gland, serum PTH rapidly fell. At 3 months after PTX, WBC rose to 23600/μl,
RBC 372×104/μl and PLT 94.0×104/μl. At 6 months, WBC was to 31000/μl, RBC 429×104/μl and PLT 78.0×104/μl, suggesting an inhibitory action of PTH on not only RBC, but also WBC and PLT. 相似文献
2.
R. Gagnemo-Persson A. Samuelsson R. Håkanson P. Persson 《Calcified tissue international》1997,61(3):210-215
Treatment with omeprazole, a long-acting proton pump inhibitor of acid secretion, induces hypergastrinemia. In chickens,
omeprazole induces growth not only of the acid-producing mucosa (probably reflecting the trophic action of gastrin), but also
of the parathyroid glands (hypertrophy + hyperplasia), while suppressing bone density and body weight gain without affecting
blood calcium. The first part of the present study was concerned with the effect of omeprazole, ergocalciferol (vitamin D2), and restricted food intake on the gene expression of parathyroid hormone (PTH) in the parathyroid glands of the chicken.
Chickens were treated with omeprazole (400 μmol/kg/day, I.M.), food restriction, omeprazole + food restriction, ergocalciferol
(250 000 IU/kg/day, S.C.), or ergocalciferol + omeprazole for 5 weeks. The weight gain of the chickens was monitored, and
the weights of the parathyroid glands and femurs were determined at sacrifice. PTH mRNA in the parathyroid glands was analyzed
by Northern blot. The second part of the study examined the effect of 3 weeks of continuous gastrin infusion (chicken gastrin
20–36, 5 nmol/kg/hour, S.C.) on the expression of PTH mRNA in the parathyroid glands. Omeprazole reduced the body weight and
femur density (ash weight per volume) while greatly increasing the weight of the parathyroid glands and the PTH gene expression.
Food restriction alone and ergocalciferol alone (at a dose that raised blood Ca2+) were without effect, but food restriction greatly enhanced the omeprazole-evoked increase in parathyroid gland weight and
PTH gene expression. Gastrin increased the weight of the parathyroid glands and reproduced the effect of omeprazole on PTH
gene expression. Hence, it seems likely that the effect of omeprazole reflects the ensuing hypergastrinemia.
Received: 6 August 1996 / Accepted: 23 April 1997 相似文献
3.
Kiyoshi Hashizume Kazuo Ichikawa Satoru Suzuki Teiji Takeda Keishi Yamauchi Mutsuhiro Kobayashi Xiao-Yun MA 《Journal of bone and mineral metabolism》1992,10(2):39-49
Calorie restriction is important in managing patients with maturity onset diabetes mellitus (NIDDM). The effect of such restriction
on calcium metabolism is not known. The objective of this study was to determine whether patients on calorie restricted diets
would show any modification of parathyroid hormone (PTH) and calcitonin (CTN).
The serum levels of PTH and CTN were measured by radioimmunoassays in 269 patients with NIDDM. The patients were divided into
two groups depending on the intake of calorie, and PTH and CTN were monitored for 2 years. Plasma levels of vitamin D were
measured by competitive protein binding assays before and after each program.
The level of PTH (520.8±266.0 pg/ml) (mean±S.D.) was significantly (P<0.01) higher in 109 diabetic patients whose calorie intake was restricted for 2 years (diet (D) group) as compared with that
(256.6±103.8 pg/ml) of 160 diabetic patients whose calorie intake was not restricted (non-diet (ND) group). The daily oral
calcium intake of the two groups did not differ significantly. We found no significant difference in the serum PTH level in
the ND groupVS. normal control subjects (248.8±98.4, N=78). The serum calcium concentration and the amount of calcium excreted in urine
were slightly but significantly (P<0.01) lower in the D than in the ND group. The rate of tubular reabsorption of phosphate (% TRP) was significantly lower
in the D group than that in the ND group (P<0.01). The serum CTN level was significantly (P<0.01) lower in the D group (33.9±11.3 pg/ml) than in the ND group (64.9±21.2 pg/ml) 2 years after each treatment. The plasma
1,25-(OH)2-vitamin D level was significantly (P<0.01) lower in the D group (22.2±6.6 pg/ml) than in the ND group (50.6±4.2 pg/ml). When
the restriction of calorie intake in the D group was canceled, their PTH levels decreased, which was accompanied by increase
in the 1,25-(OH)2-vitamin D levels, whereas their CTN levels were unchanged.
These observations suggested that a restricted calorie intake is a risk factor for secondary hyperparathyroidism as well as
for a low serum level of CTN in patients with NIDDM. 相似文献
4.
SESHA NATARAJAN STEPHEN M. FESTIN ANDERS HEDBERG EDDIE C.-K. LIU DAVID M. FLOYD JOHN T. HUNT 《Chemical biology & drug design》1992,40(6):567-574
We have developed an expeditious method for the incorporation of the biotinylaminocaproyl moiety on the ε-amino group of a lysine residue within a peptide chain in a site-specific manner. Using t-Boc chemistry for the solid phase synthesis approach and a base labile, acid stable protecting group (Fmoc-) for the ε-amino group of the target lysine, we prepared fully protected resin bound peptides which are site-specifically biotinylated. Following HF cleavage, the uniquely biotinylated peptides were obtained in a high degree of purity. Using this approach, a number of biotinylaminocaproyllysyl derivatives of a monocyclic Endothelin-1 analog were prepared. Synthesis of selected bicyclic analogs of high affinity monocycles led to the preparation of the bicyclic [Nle7]ET-1 analog containing ε-biotinylaminocaproyllysine at position-9. This peptide, with Kd= 0.08 nM, has 1000-fold higher affinity for the ETA receptor than the commercially available Nα-biotinylated Endothelin-1. The general utility of this biotinylation methodology was demonstrated by the synthesis of a site-specifically biotinylated PTH analog which contained several side chain functionalized amino acid residues in its sequence. The synthetic method reported here is convergent in that it allows the facile variation of the length of the spacer and also offers the potential to introduce in a site specific manner other groups such as affinity labels and fluorescent tags. 相似文献
5.
D. MacDonald E. Lau E. L. P. Chan T. Mak J. Woo P. C. Leung R. Swaminathan 《Calcified tissue international》1992,51(6):412-414
Summary Serum intact parathyroid hormone (PTH), 25 hydroxyvitamin D(25OHD), 1,25 dihydroxyvitamin D (1,25(OH)2D), albumin, and ionized calcium were measured in 61 Chinese female patients with hip fracture and 61 control subjects. Hip fracture patients had low albumin, ionized calcium, and 250HD levels. Serum PTH and 1,25 (OH)2D values were not different between the two groups. We conclude that although 250HD level in hip fracture patients is low, there is no evidence of secondary hyperparathyroidism, suggesting that the low 250HD levels may be a secondary phenomenon in response to the fracture. 相似文献
6.
P. SCHWARZ H. A. SØRENSEN I. TRANSBØL Mineral Metabolic Research Group 《European journal of clinical investigation》1994,24(8):553-558
Abstract. The objective of the present study was to compare the calcium set-points of E. M. Brown and A. M. Parfitt obtained by sequential citrate and calcium clamp in patients with primary hyperparathyroidism and healthy controls. Twenty-six patients with primary hyperparathyroidism were investigated and compared to 22 healthy volunteers. All participants were investigated by sequential calcium lowering and raising comprising the following four phases: Phase (1) blood ionized calcium lowering of about 0·20 mmol l-1; phase (2) steady-state (relative) hypocalcaemia of blood ionized calcium 0·20 mmol l-1 below baseline; phase (3) blood ionized calcium is raised to about 0·20 mmol l-1 above baseline; and phase (4) (relative) hypercalcaemia of blood ionized calcium 0·20 mmol l-1 above baseline. Serum parathyroid hormone (1–84) was measured by an immunoradiometric assay. Blood ionized calcium was measured by a calcium selective electrode. We found the calcium set-points of Parfitt to be 1·42 mmol l-1 (SD 0·12, n= 52) vs. 1·25 mmol l-1 (SD 0·04, n= 44) in patients and controls, respectively (P < 0·001). The calcium set-points of Brown were 1·32 mmol l-1 (SD 0·10, n= 26) vs. 1·13 mmol l-1 (SD 0·04, n= 22), respectively (P < 0·001). By comparing the calcium set-points of Parfitt and Brown, a strikingly good correlation was observed, in patients (r= 0·91, P < 0·001) and in controls (r= 0·85, P < 0·001). We demonstrate in this paper in vivo that Brown's and Parfitt's calcium set-points are raised in primary hyperparathyroidism and return to normal following parathyroidectomy. The values for Brown's and Parfitt's calcium set-points are significantly different, but strikingly well correlated, supporting the view that Brown and Parfitt describe two different points on the same sigmoidal curve, corresponding to 50% and about 85% inhibition of PTH maximum, respectively. The mathematical form of the sigmoidal curve between blood ionized calcium and parathyroid hormone is very similar in primary hyperparathyroidism and normal humans. 相似文献
7.
Kazushige Hanaoka Osamu Sakai Masashi Imai Koji Yoshitomi 《Pflügers Archiv : European journal of physiology》1993,422(4):339-346
Although net Ca2+ absorption takes place in the thick ascending limb of Henle's loop, detailed mechanisms are unknown. Because it has been reported that the Ca2+ entry step across the luminal membrane is mediated by Ca2+ channels inserted by stimulation with parathyroid hormone, we studied the mechanism of Ca2+ transport across the basolateral membrane of rabbit cortical thick ascending limb (CTAL) perfused in vitro by using microscopic fluorometry of cytosolic Ca2+ ([Ca2+]i) with fura-2. The resting [Ca2+]i in this segment was 49.8±4.5 nmol/l. Neither Na+ removal from the bathing solution nor addition of ouabain (0.1 mmol/l) to the bath increased [Ca2+]i, indicating that a Na+/Ca2+ exchanger in the basolateral membrane may not contribute in any major way to [Ca2+]i of CTAL. To confirm our technical accuracy, similar protocols were conducted in the connecting tubule, where the existence of a Na+/Ca2+ exchanger has been reported. In this segment, Na+ removal from the bath increased cell Ca2+ from 148.6 ±6.4 nmol/l to 647.6±132.0 nmol/l, confirming the documented fact. [Ca2+]i in the CTAL was markedly increased when 1 mmol/l NaCN was added to the bath in the absence of glucose. Calmodulin inhibitors (trifluoperazine or W-7) increased [Ca2+]i. When the bath pH was made alkaline, [Ca2+]i was also increased. This response was abolished when Ca2+ was eliminated from the bath, indicating that the Ca2+ entry across the basolateral membrane is dependent on bath pH. Increase in [Ca2+]i induced by an alkaline bath was inhibited by increased the bath K+ from 5 nmol/l to 50 mmol/l, suggesting that the Ca2+ entry system is voltage-dependent. However, the pH-dependent [Ca2+]i increase was unaffected by 0.1–10 mol/l nicardipine in the bath. We conclude that Ca2+ transport across the basolateral membrane of CTAL is mediated by a pump-and-leak system of Ca2+ rather than a Na+/Ca2+ exchanger secondarily linked to a Na+, K+ pump. 相似文献
8.
Background: It is not well known how the immediate precursors of osteoclast develop into osteoclasts in the fetus. This ultrastructural-cytochemical study was designed to clarify the formation process of the osteoclasts and their increased activities in the fetal mouse limb buds after administration of high dose parathyroid hormone (PTH). Methods: Twenty-four or forty-eight hours after the high doses of PTH were injected into amniotic fluid of the pregnant C3H mice, the femoral limb buds of embryos were dissected out. Tartrate-resistant acid phosphatase (TRAP) reactions were performed while preparing specimens for electron microscopy. Results: Both control and PTH-given preosteoclasts and osteoclasts exhibited TRAP-positivities in dense bodies and vesicles. As effects of PTH, a binucleated preosteoclast of tandem fashion was observed. More osteoclastic hyperactivities were observed in the diaphyseal bone marrow. An osteoclast with a large cytoplasm exhibited two sets of clear zones and ruffled borders. Some osteoclasts demonstrated prominent amoeboid figures, while other osteoclasts developed large cytoplasmic vacuoles, which contained pieces of calcified chondroid bars. Conclusions: Our results revealed the progression of maturation from young preosteoclasts to osteoclasts. An existence of a peculiar binucleated preosteoclasts suggested one of the processes for multinucleation of the osteoclast. Quite remarkable osteoclastic hyperactivities were obviously the effects of high dose PTH. Our results also indicated the endophagocytic ability of the osteoclast. How PTH affected the osteoclasts and their precursors in the diaphyseal bone marrow can be speculated. © 1995 Wiley-Liss, Inc. 相似文献
9.
H. Wald Michal Dranitzki-Elhalel R. Backenroth Mordecai M. Popovtzer 《Pflügers Archiv : European journal of physiology》1998,436(2):289-294
Vitamin D counters the phosphaturic action of parathyroid hormone (PTH) in rats in vivo. The present study was undertaken
to examine this interaction using monolayers of Opossum kidney (OK) cells. 32P uptake, cAMP generation, PTH/PTHrP receptor mRNA expression and intracellular Ca2+ [Ca2+]i were measured in (1) control cells, (2) cells exposed to PTH, (3) cells pretreated with 1,25-dihydroxyvitamin D3 [1,25(OH)2D3], and (4) 1,25(OH)2D3-pretreated cells exposed to PTH. 32P uptakes were in (1) 5.00±0.20 (mean ±SE), in (2) 2.30±0.14 (P<0.001 versus group 1), in (3) 4.80±0.24 (P NS versus group 1) and in (4) 3.70±0.20 (P<0.001 versus group 2) nmol Pi/(mg·prot 10 mm). cAMP levels were in (1) 10±3, in (2) 210±8, in (3) 12±4, and in (4) 122±12 pmol cAMP/mg protein (P<0.001 versus group 2). PTH/PTHrP receptor mRNA expression was in relative units: (1) 100±0, (2) 99.5±6.2, (3) 68.7±2.6 (P<0.001 versus group 1), and (4) 34.8±3.3 (P<0.001 versus group 1). In groups 2 and 4 PTH induced equal transient increments in [Ca2+]i. These experiments demonstrate that the effect of vitamin D on phosphate transport is associated with a commensurate diminution
in PTH/PTHrP receptor gene expression and PTH-induced cAMP formation but not with Ca2+ transients. Vitamin D per se does not affect 32P uptake or cAMP generation while it slightly decreased PTH/PTHrP receptor gene expression. These observations demonstrate
that: (1) 1.25(OH)2D3 directly antagonizes the effects of PTH on 32P uptake in OK cells, (2) this effect is mediated via inhibition of PTH-induced activation of AC/cAMP system, (3) the diminution
in PTH-induced cAMP formation may stem at least in part from a decrease in the expression of PTH/PTHrP receptor mRNA.
Received: 2 December 1997 / Received after revision: 19 January 1998 / Accepted: 28 January 1998 相似文献
10.
Intracellular recordings were made from neurones in the locus coeruleus contained within a slice cut from rat pons and maintained in vitro. Most neurones fired action potentials spontaneously at frequencies of between 1 and 5 Hz; this did not arise from spontaneous synaptic input but appeared to result from endogenous properties of the membrane conductances. Under voltage clamp at potentials near threshold for action potential generation (? 55 mV) there was a persistent inward calcium current. This current became less with membrane hyperpolarization and was abolished at about ?70 mV. Two potassium currents were observed. The first had properties similar to that generally described as the “fast” potassium current (IK,A); it flowed transiently (for about 200 ms) when the membrane potential passed from about ?65 to ?45 mV, and was blocked by 4-aminopyridine. The second was a calcium-activated potassium current (IK,Ca); it flowed for several seconds following a burst of calcium action potentials. Spontaneous and evoked action potentials had both tetrodotoxin-sensitive and tetrodotoxin-resistant components. The latter was apparently due to calcium entry. The potential changes occurring during the spontaneous firing of locus coeruleus neurones could be reconstructed qualitatively from the ionic conductances observed. The membrane properties of the locus coeruleus neurones were remarkably uniform; however, about 5% of cells impaled within the region of the locus coeruleus were electrophysiologically distinct. These atypical cells had short duration action potentials, did not fire spontaneously and had large spontaneous depolarizing synaptic potentials. 相似文献